JP4922209B2 - Washing and drying machine - Google Patents

Description

  The present invention relates to a laundry dryer for drying laundry with a heat pump.

  2. Description of the Related Art Conventionally, in a washing / drying machine, a machine provided with a heat pump for drying laundry has been attracting attention as having good drying performance and being effective in saving energy. In the washing and drying machine equipped with this heat pump, the air in the washing tub containing the laundry is circulated through the ventilation path of the heat pump in which the compressor and the cycle-connected evaporator and condenser are arranged. By repeatedly cooling and dehumidifying the air with an evaporator, heating the air with a condenser, sequentially feeding it into the washing tub, and passing the air deprived of moisture from the laundry through the air path, The laundry is gradually dried.

  Therefore, the moisture generated when the laundry is dried is collected by the evaporator, the latent heat collected in the folding is converted into a high-temperature refrigerant state by the compressor, and reused as energy for heating the air by the condenser. In this way, the energy can be reused without losing almost any energy except for a slight heat loss outside. Therefore, efficient drying can be realized.

  Thus, in such a washing dryer that dries laundry using a heat pump, it is considered that a hydrocarbon-based refrigerant is used as a refrigerant sealed in the heat pump (for example, Patent Documents 1, 2, and 3). reference). Since this hydrocarbon-based refrigerant can reduce the amount of carbon dioxide emission, it is a promising option for environmental measures.

However, hydrocarbon-based refrigerants are flammable and can ignite if leaked. Although there is no washing / drying device corresponding to the leakage of the flammable refrigerant, there is a refrigerator in which a hydrocarbon-based refrigerant is sealed in a refrigeration cycle as a cooling device (see, for example, Patent Document 4).
Japanese Patent Application Laid-Open No. 2004-293966 JP 2007-82864 A JP 2007-135728 A JP-A-8-178481

A system using a heat pump for a washing and drying machine is a system different from a refrigerator using a refrigeration cycle as a cooling device, and the operating condition of the refrigerant is higher than that of the refrigeration cycle of the refrigerator. Therefore, in the washing and drying machine, the time to reach the ignition concentration is quicker than that of the refrigerator, and faster response is required.
In addition, in the laundry dryer, static electricity may be generated due to the friction of stirring of the laundry in the washing tub in the latter half of the laundry drying, and if the flammable refrigerant leaks, There is a situation that may cause a fire

  The present invention has been made in view of the above circumstances. Therefore, the purpose of the present invention is to control the leakage of the flammable refrigerant, which is specific to the washing and drying machine, in the case where the flammable refrigerant is enclosed in the heat pump. It is in providing the washing-drying machine which can be effectively performed according to the situation.

In order to achieve the above object, in the washing and drying machine of the present invention,
A washing tub, an air circulation device that circulates air in the washing tub through a ventilation passage outside the washing tub to the inside of the washing tub by a circulation fan, and an evaporator and a condenser in the ventilation passage of the air circulation device And a compressor and a constrictor connected to each other by a connecting pipe, thereby constituting a refrigeration cycle in which a combustible refrigerant is circulated through the compressor, condenser, constrictor, and evaporator. And the washing tub, the air circulation device, and the outer box containing the heat pump, in addition to washing and dehydrating the laundry, in addition to drying the laundry by the operation of the air circulation device and the heat pump,
A first refrigerant detector disposed on the downstream side of the circulating air flow with respect to the circulation fan in the ventilation path, and an exhaust gas provided on the downstream side of the circulating air flow with respect to the first refrigerant detector in the ventilation path. Opening, opening and closing the exhaust port, and a damper provided so as to shut off the ventilation path when opened, a compressor and a throttle of the heat pump in the outer box, and the evaporator, the condenser and the condenser A cover that covers the connection pipe that connects the exhaust device, a second refrigerant detector disposed inside the cover, and an exhaust fan provided to the cover,
When drying laundry,
When the first refrigerant detector detects leakage of the flammable refrigerant, the compressor is stopped, the exhaust port is opened by the damper, the ventilation path is shut off, and the circulation fan When the second refrigerant detector detects leakage of the flammable refrigerant, the compressor is stopped and the exhaust fan is activated. The leaked refrigerant is discharged outside the outer box (invention of claim 1).

  According to the above means, when the laundry is dried, if the flammable refrigerant leaks through the ventilation path in which the evaporator and the condenser of the heat pump are disposed, the first refrigerant detector detects the leakage. . In this case, the compressor is stopped, the exhaust port is opened by the damper, the ventilation path is shut off, the circulation fan is operated, and the leakage refrigerant is discharged outside the outer box. The leaked refrigerant is quickly prevented from flowing into the washing tub through the circulating air passage. As a result, it is possible to quickly avoid the leakage refrigerant from becoming an ignition concentration in the washing tub, and the possibility of ignition due to static electricity during drying of the laundry is eliminated. In this case, since the leaked refrigerant is discharged outside the outer box, it is also possible to avoid the ignition concentration in the outer box, and even if there are electrical parts that are ignition sources in the outer box, it will be ignited. It will not reach.

On the other hand, when the laundry is also dried, the combustible refrigerant in the cover other than the evaporator and condenser of the heat pump, that is, the cover covering the compressor and the throttle and the connecting pipe connecting the evaporator and the condenser to the compressor and the condenser. Is leaked, the second refrigerant detector detects it. In this case, since the compressor is stopped and the exhaust fan is operated to discharge the leaked refrigerant outside the outer box, as described above, even if there are electrical parts that are ignition sources in the outer box, It will not lead to.
Thus, in a washing / drying machine that uses a flammable refrigerant enclosed in a heat pump, the control of leakage of the flammable refrigerant can be effectively performed in accordance with the circumstances specific to the washing / drying machine.

Hereinafter, an example (one embodiment) of the present invention will be described with reference to the drawings.
First, as shown in FIG. 2, the front part (the left part in FIG. 2) of the outer box 1 that forms the outer shell of the entire washing and drying machine has a laundry entrance 2, which is opened and closed by a door 3. Like to do.

  Inside the outer box 1, the water tank 4 is arranged in a horizontal axis shape as shown in FIG. 2 with a plurality of elastic support devices 5 shown in FIG. A drum 6 serving as a washing tub is arranged in parallel with and concentrically with the water tub 4. The drum 6 has a porous shape having a large number of holes 6a in the almost entire region of the peripheral wall (only a part of the holes 6a are shown), and a motor 7 that is a driving device for rotating the drum 6 with a rotating shaft 7a is provided. It is attached to the back of the water tank 4.

  A ventilation case 8 is disposed below the water tank 4, and the front part of the ventilation case 8 is formed in the upper part of the front part of the water tank 4 via a suction duct 9 having a flexible part 9 a. Tens. On the other hand, the rear part of the ventilation case 8 is connected to the inlet 12 formed in the upper part of the inner part of the water tank 4 through the discharge duct 11 having the flexible part 11a. The suction duct 9, the ventilation case 8, And the discharge duct 11 connects the air outlet 10 and the air inlet 12 of the water tank 4 to form a ventilation path 13. Therefore, the ventilation path 13 is located outside the water tank 4.

  Thus, the evaporator 14 is disposed on the suction duct 9 side and the condenser 15 is disposed on the discharge duct 11 side in the ventilation path 13, particularly inside the ventilation case 8. Although not shown in detail, the evaporator 14 and the condenser 15 are both of a finned tube type in which a large number of heat transfer fins made of, for example, an aluminum plate are attached to a meandering, eg, copper refrigerant circulation pipe. Therefore, air passing through the ventilation case 8 as described below flows between the heat transfer fins.

Further, a circulation fan 16 is disposed on the discharge duct 11 side further than the condenser 15 in the ventilation case 8. The circulation blower 16 circulates the air in the drum 6 through the ventilation path 13 and then returns to the drum 6 by the air blowing action as shown by arrows in FIG. Thus, the air circulation device 17 that circulates the air in the drum 6 is constituted by the ventilation path 13 and the circulation fan 16.
In addition, an outside air inlet 18 is formed in the ventilation case 8 on the discharge duct 11 side (between the condenser 15) from the evaporator 14, and exhaust heat is formed on the suction duct 9 side from the evaporator 14. Mouth 19 is formed.

  Further, a cover 20 is disposed around the ventilation case 8 such as behind (see FIG. 2) or side (see FIG. 3). In this case, an electronic throttle valve) 22, an accumulator 23 shown in FIG. 4, and connecting pipes 24, 25, 26, 27 for connecting them to the condenser 15 and the evaporator 14 as shown in FIG. Are arranged so as to cover them. In addition, a part of the U-shaped bent portions 15 a and 14 a of the refrigerant circulation pipe exposed from the heat transfer fins of the condenser 15 and the evaporator 14 are also located inside the cover 20.

The connection form of the compressor 21, the throttle 22, the accumulator 23, the condenser 15, and the evaporator 14 by the connection pipes 24 to 27 is as follows: compressor 21-condenser 15-throttle 22-evaporator 14-accumulator 23- They are connected in the order of the compressor 21, thus forming a heat pump 28 composed of a refrigeration cycle. In this case, the heat pump 28 (refrigeration cycle) encloses a combustible natural refrigerant such as a hydrocarbon-based refrigerant (hydrocarbon).
FIG. 4 schematically shows the water tank 4 and the ventilation path 13 (the suction duct 9, the ventilation case 8, and the discharge duct 11) and the outer box 1 that accommodates them together with the heat pump 28. .

  Here, a first refrigerant detector 29 is arranged in the lower part of the discharge duct 11 (on the ventilation case 8 side) in the ventilation path 13, which is downstream of the circulating air flow from the circulation fan 16. is doing. The first refrigerant detector 29 is a gas sensor that detects the flammable refrigerant. When the upper limit of the safe concentration, for example, the flammable refrigerant is isobutane, the lower limit value of the flammable concentration of the isobutane is about 2% by weight. If it is, it will detect that the combustible refrigerant | coolant has leaked when it reaches about 0.4% of about 1/5 of it.

  Further, an exhaust port 30 is provided in an intermediate portion of the discharge duct 11 in the ventilation path 13, which is further downstream of the circulating air flow than the first refrigerant detector 29. A damper 31 is provided. The damper 31 is rotated by a motor (not shown) to open and close the exhaust port 30 as shown by a solid line and a broken line in FIG.

  On the other hand, a second refrigerant detector 32 is arranged inside the cover 20, particularly in this case, inside the portion covering the compressor 21. The second refrigerant detector 32 is the same as the first refrigerant detector 29, and therefore detects the leakage of the flammable refrigerant in the same manner as the first refrigerant detector 29.

Further, an exhaust blower 33 is provided for the cover 20. Specifically, the exhaust blower 33 is provided outside the portion of the cover 20 that covers the compressor 21.
In addition, an inlet temperature detector 34 is provided outside the refrigerant inlet portion of the evaporator 14, and an outlet temperature detector 35 is provided outside the refrigerant outlet portion of the evaporator 14.

  FIG. 5 shows the control device 36. The control device 36 is composed of, for example, a microcomputer, and is located in the outer box 1 and functions as control means for controlling the overall operation of the washing / drying machine.

  Various control signals are input to the control device 36 from an operation input unit 37 including various control switches provided on an operation panel (not shown), and a water level detection signal is received from a water level sensor 38 that detects the water level in the water tank 4. The refrigerant detection signals are input from the first refrigerant detector 29 and the second refrigerant detector 32, respectively, and the temperature detection signals are input from the inlet temperature detector 34 and the outlet temperature detector 35, respectively. It has become so.

  And the control apparatus 36 is based on the input of the said various signals, and the control program memorize | stored previously, The water supply valve 39 provided so that the water tank 4 may be supplied with water, the said motor 7, the circulation fan 16, and the compressor 21 , A throttle 22, a damper driving motor 40, an exhaust blower 33, a drain valve 41 provided to open and close the drain port of the water tank 4, and a buzzer 42 as an alarm are controlled via a drive circuit 43. It is like that.

Next, the operation of the above configuration will be described.
First, a schematic operation of the washing / drying machine will be described. When an operation panel (not shown) is operated by the user to set a course of driving and an instruction to start driving is given, the washing / drying machine performs a washing operation, a drying operation, or both according to the set driving course. A washing / drying operation is performed in which the operation is continued. As one of them, when the execution of the washing and drying operation is started, the washing process, the dehydrating process, and the drying process are executed in order.

  In the washing process, after supplying the water tank 4 by opening the water supply valve 39, the drum 6 is rotated at a low speed. In the dehydration process, after the drain valve 41 is opened and the water in the water tank 4 is discharged, an operation of rotating the drum 6 at high speed is performed. In the drying process, an operation for supplying warm air into the drum 6 is performed while rotating the drum 6 at a low speed.

  The operation of supplying warm air into the drum 6 is performed in detail as follows. In other words, the circulation fan 16 is normally operated, whereby the air in the drum 6 flows from the air outlet 10 of the water tank 4 into the ventilation case 8 through the suction duct 9 of the ventilation path 13 and then the ventilation case 8. It passes through the inside and the discharge duct 11 in order, and is returned from the inlet 12 of the water tank 4 into the drum 6. At this time, the damper 31 is set in a state in which the exhaust port 30 is closed (position indicated by a broken line in FIG. 4).

  At this time, the heat pump 28 drives the compressor 21. Thereby, the refrigerant (gas) is compressed by the compressor 21 to become high temperature and high pressure, and the high temperature and high pressure refrigerant flows into the first condenser 15 to exchange heat with the air passing through the ventilation case 8. As a result, the air passing through the ventilation case 8 is heated, and conversely, the temperature of the refrigerant is lowered and liquefied. The liquefied refrigerant is then depressurized through the first restrictor 22 and then flows into the first evaporator 14 to be vaporized. At this time, the behavior of the refrigerant is detected from the detected temperatures of the inlet temperature detector 34 and the outlet temperature detector 35 attached to the first evaporator 14, and the throttle 22 is controlled to be throttled according to the detection result.

  The refrigerant vaporized by the first evaporator 14 cools the air passing through the ventilation case 8. The refrigerant that has passed through the first evaporator 14 returns to the compressor 21 via the accumulator 23. As a result, the air flowing from the drum 6 into the ventilation case 8 is cooled by the first evaporator 14 and dehumidified, and then heated by the first condenser 15 to be warmed. Then, the warm air passes through the discharge duct 11 and is supplied into the drum 6 from the inlet 12 of the water tank 4.

  Thus, the hot air supplied into the drum 6 deprives the laundry of moisture, and then flows into the ventilation case 8 from the air outlet 10 of the water tank 4 through the suction duct 9. Thus, the air in the ventilation case 8 having the evaporator 14 and the condenser 15 circulates between the drum 6 and the laundry in the drum 6 is dried.

Further, during this drying operation, the exhaust blower 33 is operated normally, the moisture in the outer box 1 is discharged from an appropriate gap in the outer box 1, and the same amount of outside air outside the outer box 1 is also output from the outer box 1. In order to prevent dew condensation in the outer box 1, it is introduced through the appropriate gap.
These operations are as shown in the column “During normal operation” in FIG.

  Now, when the laundry is being dried in this way, if the first refrigerant detector 29 detects leakage of the refrigerant, it means that the condenser 15 located in the ventilation path 13 (in the ventilation case 8). Alternatively, the refrigerant leaks from the respective refrigerant circulation pipes of the evaporator 14, and this is represented as “A: refrigerant leakage in the ventilation path” in FIG. 1, and the detected concentration in the first refrigerant detector 29 is safe. The upper limit is exceeded (otherwise, it is the same as the “normal operation”).

  In this case, as a “refrigerant leak control” corresponding to that, an alarm is generated by operating the buzzer 42 (not shown), the compressor 21 is stopped, and at the same time, the throttle 22 is fully closed, The circulation blower 16 is operated in the strongest air blowing state where the air volume is larger than that of “normal”, for example, and the damper 31 is opened (the exhaust port 30 is opened and the ventilation path 13 is shut off).

  As a result, the leakage of new refrigerant from the refrigerant distribution pipes of the condenser 15 and the evaporator 14 was stopped, and the refrigerant leaked into the ventilation path 13 was stopped from flowing into the drum 6 by the damper 31. In this state, the air is discharged from the exhaust port 30 to the outside of the ventilation path 13, and is further discharged to the outside of the outer box 1 through an appropriate gap of the outer box 1. Thus, the refrigerant leaked in the ventilation passage 13 is quickly prevented from flowing into the drum 6, and the ignition concentration in the drum 6 is also quickly avoided, and the possibility of ignition due to static electricity during the drying of the laundry. Disappears. Further, in this case, since the leaked refrigerant is discharged out of the outer box 1, it is possible to avoid an ignition concentration in the outer box 1, and even if there are electrical parts or the like serving as an ignition source in the outer box 1. Does not lead to fire.

  And the detection density | concentration in the 1st refrigerant | coolant detector 29 reduces gradually, and becomes below a safe upper limit density | concentration eventually. Therefore, the operation of the circulation fan 16 is stopped as “control after leakage”, but the operation of the circulation fan 16 is continued depending on the detected concentration in the first refrigerant detector 29 (see FIG. 1). "ON / OFF control"). In this case, the compressor 21 is stopped, the restrictor 22 is fully closed, and the damper 31 is left open.

  On the other hand, when the laundry is similarly dried, if the second refrigerant detector 32 detects the leakage of the refrigerant, it means that other than the evaporator 14 and the condenser 15 of the heat pump 28, that is, the compressor 21. The refrigerant leaks in the cover 20 that covers the restrictor 22, the accumulator 23, and the connection pipes 24-27. This is expressed as “B: refrigerant leakage outside the ventilation path” in FIG. The detected concentration in the refrigerant detector 32 of No. 2 exceeds the safe upper limit value (otherwise, this is also the same as the “normal operation”).

  In this case, as a “refrigerant leak control” corresponding to that, an alarm is generated by operating the buzzer 42 (not shown), the compressor 21 is stopped, the throttle 22 is fully closed, and the exhaust The blower 33 is operated in a state where the air flow is larger than that of “normal”, for example, in the strongest air blowing state (the circulation fan 16 remains normally operated, the damper 31 is closed, that is, the exhaust port 30 is closed, and the ventilation path 13 is opened. Remain).

  As a result, leakage of new refrigerant from the compressor 21, the throttle 22, the accumulator 23, and any of the connection pipes 24-27 is stopped, and the refrigerant leaking into the cover 20 It is discharged out of the cover 20 from the gap, and further discharged out of the outer box 1 through an appropriate gap in the outer box 1. Thus, it is avoided that the refrigerant leaked in the cover 20 (outside the ventilation path 13) has an ignition concentration in the outer box 1, and even if there are electrical parts or the like serving as an ignition source in the outer box 1, It will not reach.

  And the detection density | concentration in the 2nd refrigerant | coolant detector 32 reduces gradually, and becomes below a safe upper limit density | concentration eventually. Therefore, as “control after leakage”, the operation of the exhaust fan 33 is stopped, but the operation of the exhaust fan 33 is continued depending on the detected concentration in the second refrigerant detector 32 (FIG. 1). "ON / OFF control"). In this case, the compressor 21 is stopped, the restrictor 22 is fully closed, and the damper 31 is closed.

  As described above, in this configuration, when the combustible refrigerant leaks through the ventilation path 13 in which the evaporator 14 and the condenser 15 of the heat pump 28 are disposed, the first refrigerant detector 29 detects it. Based on this, the compressor 21 is stopped, the exhaust port 30 of the ventilation path 13 is opened by the damper 31 and the ventilation path 13 is shut off, and the circulating fan 16 is operated to remove the leaked refrigerant outside the outer box 1. Discharge. When the combustible refrigerant leaks in the cover 20 that covers the compressor 21, the throttle 22, the accumulator 23, and the connection pipes 24 to 27 except for the evaporator 14 and the condenser 15 of the heat pump 28. The second refrigerant detector 32 detects this, and based on that, the compressor 21 is stopped, the exhaust blower 33 is operated, and the leaked refrigerant is discharged out of the outer box 1. As a result, in the washing / drying machine in which the combustible refrigerant is enclosed in the heat pump 28, the control of the leakage of the combustible refrigerant can be effectively performed in accordance with the circumstances specific to the washing / drying machine. The possibility can be eliminated.

  In addition, in this configuration, although not shown, even when the laundry is not dried, the exhaust fan 33 is periodically operated to exhaust the air from the outer box 1 to the outside of the outer box 1. Like to do. Therefore, when the laundry is not dried, even if the flammable refrigerant leaks in the cover 20 for some reason, the leaked refrigerant can be periodically discharged out of the outer box 1 and may ignite. Can be eliminated.

  Even when the laundry is not dried, if the refrigerant leakage is detected by the second refrigerant detector 32, the circulation blower 16 and the exhaust blower 33 are both operated in the strongest blowing state, and the damper 31 is opened (the exhaust port 30 is opened and the ventilation path 13 is shut off). As a result, in a state where the flow of air through the evaporator 14 and the condenser 15 into the drum 6 is stopped, the air is discharged out of the outer box 1 and at the same time, the air in the cover 20 is discharged outside the outer box 1. To be discharged. In this case as well, if the detected concentration of the second refrigerant detector 32 is equal to or lower than the safe upper limit concentration, the operation of the circulation fan 16 and the exhaust fan 33 is stopped, but the second refrigerant detector 32 Depending on the detected concentration, the operation of the circulation fan 16 and the exhaust fan 33 is continued.

  The present invention is not limited to the embodiment described above and shown in the drawings. In particular, the exhaust blower 33 may be provided inside the cover 20, and as a whole of the washing and drying machine, It is not limited to the above-mentioned horizontal axis shape, it may be a vertical axis shape having a washing tub in a vertical axis shape, and the washing tub may not rotate. Can be implemented.

The figure showing the situation when there was a refrigerant leak from the control contents at the time of normal drying operation, and each control contents at that time, showing one embodiment of the present invention Longitudinal side view of washer / dryer Longitudinal front view of the washer / dryer Schematic configuration diagram of a washing dryer Electrical configuration block diagram

Explanation of symbols

  In the drawings, 1 is an outer box, 6 is a drum (washing tub), 13 is an air passage, 14 is an evaporator, 15 is a condenser, 16 is a circulation fan, 17 is an air circulation device, 20 is a cover, and 21 is compression. , 22 is a throttle, 24 to 27 are connection pipes, 28 is a heat pump, 29 is a first refrigerant detector, 30 is an exhaust port, 31 is a damper, 32 is a second refrigerant detector, and 33 is an exhaust fan. , 36 indicates a control device.

Claims (2)

A washing tub,
An air circulation device that performs circulation to return the air in the washing tub to the inside of the washing tub through a ventilation path outside the washing tub with a circulation fan;
By arranging an evaporator and a condenser in the ventilation path of the air circulation device and connecting them with a compressor and a throttle by a connection pipe, the combustible refrigerant is removed from the compressor, the condenser and the throttle. And a heat pump that constitutes a refrigeration cycle that circulates through the evaporator,
They have a washing tub, an air circulation device, an outer box containing a heat pump,
In addition to performing washing and dehydration of the laundry, the laundry is dried by the operation of the air circulation device and the heat pump.
A first refrigerant detector disposed on the downstream side of the circulating air flow from the circulating fan of the ventilation path;
An exhaust port provided further downstream of the circulating air flow than the first refrigerant detector of the ventilation path;
A damper provided to open and close the exhaust port and to block the ventilation path when the exhaust port is opened;
A cover in the outer box covering a compressor and a throttle of the heat pump, and a connection pipe connecting them to the evaporator and condenser;
A second refrigerant detector disposed inside the cover;
An exhaust blower provided for the cover;
When drying laundry,
When the first refrigerant detector detects leakage of the flammable refrigerant, the compressor is stopped, the exhaust port is opened by the damper, the ventilation path is shut off, and the circulation fan To discharge the leaked refrigerant out of the outer box,
When the second refrigerant detector detects leakage of the combustible refrigerant, the compressor is stopped and the exhaust fan is operated to discharge the leaked refrigerant out of the outer box. A washing dryer characterized by that.   2. The laundry dryer according to claim 1, wherein when the laundry is not dried, the exhaust fan is periodically operated to exhaust air from the outer box to the outside of the outer box.

Images