JP5448656B2 - Air conditioner - Google Patents

Description

  The present invention relates to an air conditioner that performs preheating for heating.

  In an air conditioner equipped with a heat pump refrigeration cycle capable of cooling and heating, there is a problem that the start-up of heating is slow because the use period of heating, the refrigerant, and the indoor heat exchanger are cold.

  Therefore, an air conditioner is known in which a compressor is started before a heating start time set in advance by a timer, thereby performing a preheating operation for warming the indoor heat exchanger, thereby speeding up the start of heating ( For example, Patent Document 1).

JP 2001-208393 A

  When the pre-heating operation is performed at a low outside air temperature, the refrigerant solubility (dilution) in the lubricating oil inside the compressor is increased. Especially when starting at a low speed, the oil film on the sliding part of the compressor However, in the worst case, metal contact occurs in the compressor, and the compressor is locked or damaged.

  This invention considers the said situation, The objective is to provide the air conditioner excellent in the reliability which can eliminate the lock | rock and damage of the compressor at the time of a preheating operation.

An air conditioner according to a first aspect of the present invention has two cylinders and allows discharge refrigerant of a compressor capable of switching between two-cylinder operation and one-cylinder operation to pass through an indoor heat exchanger, a decompressor, and an outdoor heat exchanger. A heat pump refrigeration cycle capable of forming a heating flow path returning to the compressor, an indoor fan for circulating indoor air through the indoor heat exchanger, and a preheating condition for heating based on the indoor temperature and the outdoor temperature The indoor fan is operated at a very low speed, and the compressor is first operated with a capacity of 2 cylinders and higher than the low capacity, and then is operated with a capacity of 1 cylinder and with a low capacity to form the heating flow path. Control means for executing a preheating operation for heating the indoor heat exchanger.

  According to the air conditioner of this invention, the lock and damage of the compressor during the preheating operation can be eliminated, and the reliability is improved.

The external appearance perspective view of the indoor unit in one Embodiment of this invention. The figure which shows the internal structure of the indoor unit in one Embodiment in cross section. The figure which shows the structure of the heat pump type | mold refrigerating cycle in one Embodiment, and 2 cylinder operation | movement of a compressor. The figure which shows 1 cylinder operation | movement of the compressor in one Embodiment. The block diagram which shows the control circuit of the indoor unit in one Embodiment. The figure which shows the remote control in one Embodiment. The block diagram which shows the control circuit of the outdoor unit in one Embodiment. The flowchart for demonstrating operation | movement of one Embodiment. The figure which shows the preheating operation area | region in one Embodiment. The figure which shows the driving | operation ON / OFF of the compressor at the time of the preheating driving | operation in one Embodiment, and the opening degree change of an electronic expansion valve.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows the appearance of the indoor unit, and FIG. 2 shows a cross section of the interior of the indoor unit.
Reference numeral 1 denotes an indoor unit, which includes a front panel 1A that forms a contour with a front surface curved in a side view, and a rear main body 1B that has components housed therein. A top suction port 2 is provided on the upper surface of the front panel 1A, a front suction port 3 is provided on the front surface of the front panel 1A, leaving a lower portion, and a blower outlet 4 is opened at the lower front surface of the front panel 1A. A grill 5 is fitted into the upper surface suction port 2, and the upper surface suction port 2 is always open. The front portion of the front panel 1A is rotatably opened and closed supported on the upper front end of the rear main body via a hinge portion (not shown) at the upper end here. Therefore, the lower end portion of the front panel 1A can be opened and closed with respect to the rear body.

  The front suction port 3 provided on the front surface of the front panel 1A is opened and closed by a movable panel 6 attached via a panel opening / closing mechanism K. That is, the movable panel 6 is opened by a forward protrusion based on the operation of the panel opening / closing mechanism K to form an indoor air suction passage, and the suction passage is closed by returning from the protrusion position. In addition, the movable panel 6 includes a transmissive display portion 6a at a portion corresponding to a display unit 20 described later. The transmissive display unit 6 a constitutes display means together with the display unit 20, and is formed of a light transmitting member. The transmissive display unit 6 a displays the display of the display unit 20 on the front side of the indoor unit 1.

  Inside the indoor unit 1, an indoor heat exchanger 9 formed by bending the front heat exchanger portion 9 </ b> A and the rear heat exchanger portion 9 </ b> B into a substantially inverted V shape is disposed. The front heat exchanger section 9A is formed in a curved shape at a position corresponding to the front panel 1A and the movable panel 6. The rear heat exchanger portion 9B is provided at an inclination at a position corresponding to the upper surface suction port 2.

  An electric dust collector 10 is attached to the front side of the front heat exchanger section 9A. The electric dust collector 10 operates as an ozone generator in addition to the original dust collecting operation. A filter 11 is interposed between the indoor heat exchanger 9 and the front suction port 3 and the upper suction port 2. If the front panel 1 </ b> A is opened together with the movable panel 6, the filter 11 can be easily inserted into and removed from the indoor unit 1. Although not shown, a cleaning unit that automatically cleans dust adhering to the filter 11 is provided.

  An indoor fan 12 is provided between the front and rear indoor heat exchangers 9A and 9B of the indoor heat exchanger 9 and at a position facing the air outlet 7. The indoor fan 12 is a so-called cross-flow fan, has an axial dimension substantially the same as the width dimension of the indoor heat exchanger 9, and circulates indoor air through the indoor heat exchanger 9. The lower end portion of the front heat exchanger 9A is placed on the front drain pan 13a, and the lower end portion of the rear heat exchanger portion 9B is placed on the rear drain pan 13b, receiving drain water dripping from each heat exchanger, Can be drained. The outer surfaces of the side walls of the front and rear drain pans 13a and 13b are provided at positions close to the indoor fan 12, and constitute a nose n for the indoor fan 12. A partition wall member 14 connects the side wall portions of the front and rear drain pans 13a and 13b constituting the nose n and each side portion of the outlet 4. A space surrounded by the partition wall member 14 becomes a blowout air passage 15 that communicates the nose n and the blowout port 4. Up and down louvers 7 </ b> A and left and right louvers 7 </ b> B are provided at the outlet 4 that opens at the end portion of the blowout air passage 15. Here, a plurality of left and right louvers 7B connected to each other via an operating mechanism are supported on one upper and lower louvers 7A. The upper and lower louvers 7A and the left and right louvers 7B are also mechanically connected to each other via a drive mechanism and a drive source (not shown).

  The heat pump refrigeration cycle shown in FIG. 3 is mounted on the indoor unit 1 and the outdoor unit (not shown) having such a configuration. Reference numeral 40 denotes a two cylinder type compressor having two cylinders 41 and 42. During heating, the refrigerant discharged from the compressor 40 flows through the four-way valve 43 to the indoor heat exchanger 9, and the refrigerant passing through the indoor heat exchanger 9 passes through an electronic expansion valve (pulse motor valve; PMV) 44. To the outdoor heat exchanger 45. The refrigerant that has passed through the outdoor heat exchanger 45 is sucked into the cylinder 41 via the four-way valve 43 and the accumulator 47, and part of the refrigerant that has passed through the accumulator 47 is sucked into the cylinder 42 via the switching valve 48 and the buffer tank 49. Be turned. That is, a heating channel is formed. An outdoor fan 46 is provided in the vicinity of the outdoor heat exchanger 45.

  At the time of cooling, the four-way valve 43 reversely operates, so that the refrigerant discharged from the compressor 40 flows to the outdoor heat exchanger 45 through the four-way valve 43 as indicated by the broken line arrow, and the outdoor heat exchanger 45 The refrigerant that has passed through flows through the electronic expansion valve 44 to the indoor heat exchanger 9. The refrigerant that has passed through the indoor heat exchanger 9 is sucked into the cylinder 41 via the four-way valve 43 and the accumulator 47, and part of the refrigerant that has passed through the accumulator 47 is sucked into the cylinder 42 via the switching valve 48 and the buffer tank 49. Be turned. That is, a cooling channel is formed.

  The switching valve 48 forms a refrigerant flow path connecting the accumulator 47 and the buffer tank 49 as shown in the figure when the compressor 40 is operated in two cylinders, and when the cylinder 42 of the compressor 40 is in the idling state, As shown in FIG. 4, a refrigerant flow path in which a part of the refrigerant discharged from the compressor 40 returns to the cylinder 42 is formed while blocking the refrigerant flow path connecting the accumulator 47 and the buffer tank 49.

  On the other hand, one side portion of the indoor heat exchanger 9 is arranged with a gap from the side plate of the indoor unit 1, and the electric component box 16 is arranged in this gap. The electrical component box 16 accommodates the indoor substrate 50, the light transmitting / receiving substrate 70, and the display substrate 80 shown in FIG.

  The indoor board 50 is connected to the commercial AC power supply AC, takes in the AC voltage of the commercial AC power supply AC into the power supply circuit 52 through the power switch 51, and supplies the AC voltage of the commercial AC power supply AC through the power relay 53. It sends out to the outdoor substrate 200 of the outdoor unit. The power supply circuit 52 steps down and rectifies the AC voltage taken in, and outputs it as operating voltages for the indoor substrate 50, the light transmitting / receiving substrate 70 and the display substrate 80.

  An indoor control unit (MCU) 60, drive circuits 61, 62, 63, 64, 65, and a serial circuit 66 are mounted on the indoor substrate 50. The indoor control unit 60 controls the entire air conditioner together with an outdoor control unit 203 (described later) on the outdoor substrate 200 by transmitting and receiving data to and from the outdoor substrate 200 via the serial circuit 66. The drive circuit 61 drives the upper and lower louvers 7A, the left and right louvers 7B, and the movable panel 6. The drive circuit 62 drives the electric dust collector 10 and the filter 11. The drive circuit 63 drives the light transmission / reception unit 71 on the light transmission / reception substrate 70. The drive circuit 64 drives the display unit 20 on the display substrate 80. The drive circuit 65 drives the fan motor 12M of the indoor fan 12 at a variable speed.

  In addition, a sensor group 67, a panel detector 68, and a filter detector 69 are connected to the indoor control unit 60. The sensor group 67 includes an indoor temperature sensor that detects the indoor temperature TA, a heat exchanger temperature sensor that detects the temperature TC of the indoor heat exchanger 9, and a refrigerant temperature sensor that detects the temperature TCJ of the refrigerant flowing out of the indoor heat exchanger 9. And an indoor humidity sensor for detecting indoor humidity. The panel detector 68 detects opening / closing of the movable panel 6. The filter detector 69 detects insertion / removal of the filter 11.

  The light transmission / reception unit 71 receives infrared light for operation emitted from a remote control type operating device (referred to as a remote controller) 100 and emits infrared light for data transmission to the remote control 100.

  As shown in FIG. 6, the remote controller 100 includes a liquid crystal display unit 101, a temperature adjustment button 102, an automatic button 103, a cooling button 104, a stop button 105, a dehumidifying button 106, a heating button 107, an airflow button 108, and an open / close cover (illustrated). (Not) inside operation surface 110. On this operation surface 110, a timer button 111 for setting a time until the operation is stopped, an “information” button 112 for information guidance, a wind direction button 113 for switching the up / down wind direction and the left / right wind direction, and the operation of the electric dust collector 10. An air clean button 114 for setting the air volume, an air volume button 115 for setting the blown air volume, a swing button 116 for setting the swing of the upper and lower louvers 7A, for example, only in the morning, only at night, in the morning and at night Preheating button 117 for setting a preheating operation mode for heating, etc., timer cut button 118 for setting a reserved time (time) for stopping operation, and a timer for setting a reserved time (time) for starting operation A button 119, a reservation button 120 for confirming these reservation times (time), a menu button 121, and a cancel button 122 are provided.

  About the reservation time (time) of the operation start by the button with a timer 119, it can set about each operation | movement of cooling, dehumidification, ventilation, and heating. The preheating operation time can be set with the preheating button 117 by setting operation modes such as morning only, night only, morning and night with the preheating button 117, and setting the time with the menu button 121.

  On the other hand, as shown in FIG. 7, a power supply circuit 201, an outdoor control unit (MCU) 203, drive circuits 204 and 205, an inverter 206, and drive circuits 207 and 208 are mounted on an outdoor substrate 200 of the outdoor unit. The power supply circuit 201 converts the AC voltage supplied from the indoor board 50 into an operating voltage for the outdoor board 200 and outputs the converted voltage. The drive circuit 204 drives the electronic expansion valve 44. The drive circuit 205 drives the switching valve 48. The inverter 206 drives the compressor 40 at a variable speed by controlling an output frequency (also referred to as an operation frequency) F of a drive voltage for the compressor motor 40M of the compressor 40 according to a command from the outdoor control unit 203 ( (Capacity variable operation). The drive circuit 207 drives the four-way valve 43. The drive circuit 208 drives the fan motor 46M of the outdoor fan 46 at a variable speed.

  A sensor group 209 is connected to the outdoor control unit 203. The sensor group 209 detects the temperature of the refrigerant discharged from the compressor 40, the temperature of the refrigerant discharged from the compressor 40, the temperature of the refrigerant sucked into the compressor 40, and the temperature of the outdoor heat exchanger 45. A heat exchanger temperature sensor that detects the outdoor temperature, and an outdoor air temperature sensor that detects the outdoor temperature TO.

  And the indoor control part 60 and the outdoor control part 203 have the following means (1)-(5) as main functions regarding the preheating operation for heating.

  (1) When the preheating condition for heating based on the indoor temperature TA detected by the indoor temperature sensor of the sensor group 67 and the outdoor temperature TO detected by the outdoor temperature sensor of the sensor group 209 is satisfied, the compressor 40 is operated at a low capacity ( Control means for performing a preheating operation for heating the indoor heat exchanger 9 while reducing the number of operating cylinders) and forming a heating flow path of the heat pump refrigeration cycle.

  (2) Control means for operating the compressor 40 at a capacity higher than the low capacity at the beginning and then operating at a low capacity during the preheating operation.

  (3) During the preheating operation, the indoor fan 12 is operated at an extremely low speed to form a short circuit in which the blown air circulates in the shortest path from the blower outlet 4 to the upper surface suction port 2 as shown by a thick arrow in FIG. Control means.

  (4) Control means for notifying that effect by displaying on the display unit 20 during the preheating operation.

  (5) The capacity of the compressor 40 is increased and a heat exchanger temperature sensor is received when a heating start instruction is received by operating the remote controller 100 during preheating operation or when the heating start time is set by the remote controller 100 setting. Control means for operating or stopping the indoor fan 12 at a low speed until the detected temperature TC reaches the set value TCx, and when the detected temperature TC exceeds the set value TCx, the speed of the indoor fan 12 is rapidly increased to shift to the heating operation. .

Next, the operation will be described with reference to the flowchart of FIG.
When the indoor temperature TA detected by the indoor temperature sensor is, for example, 15 ° C. or lower and the outdoor temperature TO detected by the outdoor air temperature sensor is, for example, 10 ° C. or lower, and enters the preheating operation region shown in FIG. Under the judgment that it has been established (YES in step 301), the operation of the compressor 40 and the operation of the outdoor fan 46 are started, and the four-way valve 43 is inverted to form the heating flow path of the heat pump refrigeration cycle. Then, the preheating operation for heating for heating the indoor heat exchanger 9 is started (step 302).

  During this preheating operation, the indoor fan 12 is operated at an extremely low speed, and as shown in FIG. 1, a short circuit is formed for circulating the blown air along the shortest path from the outlet 4 to the upper surface inlet 2.

  Further, during the preheating operation, the characters “in preheating” are displayed on the display unit 20, and the display is transmitted through the transmission display portion 6a of the movable panel 6 (step 303). The user in the room can know that the preheating operation is being performed by viewing the transmission display of the transmission display unit 6a. And time count t1 is started with the start of thermal operation (step 304).

  When there is no instruction to start heating by operating the remote controller 100 and the heating start time by the setting operation of the remote controller 100 has not been reached (NO in step 305), the time count t1 and the set time t1x are compared (in step 315). YES). If the time count t1 is less than the set time t1x (NO in step 315), the operating frequency F of the compressor 40 is set to an operating frequency F2 (> F1) higher than the operating frequency F1 for low capacity (step 307). . Thereafter, when the time count t1 reaches the set time t1x (YES in Step 315), the operating frequency F of the compressor 40 is reduced to the operating frequency F1 for low capacity (Step 308).

  When the pre-heating operation is performed at a low outside air temperature, the refrigerant solubility (dilution degree) in the lubricating oil in the compressor 40 is in an increased state, and particularly when the engine is started at a low rotational speed, the sliding portion of the compressor 40 In the worst case, metal contact occurs in the compressor 40, and the compressor 40 may be locked or damaged.

  In order to prevent such problems, in the state where the refrigerant solubility (dilution degree) immediately after the start of the compressor 40 is high, the operation frequency F2 is set as described above and the compressor 40 is operated with a higher capacity than the low capacity. As a result, an oil film on the sliding portion of the compressor 40 can be secured, thereby preventing the compressor 40 from being locked or damaged. Then, when the time count t1 reaches the set time t1x and enters a stable state where the refrigerant solubility (dilution degree) increases, the operation frequency F1 (<F2) is set and the compressor 40 is operated at a low capacity. Electric power can be reduced, and an energy saving effect can be obtained.

  During the preheating operation, as shown in FIG. 10, the operation of the compressor 40 is turned on and off (intermittent), and the opening degree of the electronic expansion valve 44 is controlled along with the on and off, The temperature of the indoor heat exchanger 9 (detected temperature of the heat exchanger temperature sensor) TC is maintained within a predetermined range. When controlling the opening of the electronic expansion valve 44, an initial opening (number of drive pulses; 60 pls) is first set at the start of preheating, and then the temperature TCJ of the refrigerant flowing out of the indoor heat exchanger 9 (detection of the refrigerant temperature sensor). The degree of opening is increased or decreased so that the degree of superheat (superheat amount) SH, which is the difference between the temperature) and the heat exchanger temperature TC, becomes a constant value.

  When the preheating operation is performed in this manner, when an instruction to start heating is issued by operating the remote controller 100 or when the heating start time by the setting operation of the remote controller 100 is reached (YES in step 305), the operating frequency of the compressor 40 F (driving capability) is increased (step 309), and the indoor fan 12 is operated or stopped at a low speed (step 310). At the same time, the “preheating” display on the display unit 20 is canceled (step 311), and the time count t1 is cleared (step 312).

  At this time, if the temperature TC of the indoor heat exchanger 9 is equal to or lower than the set value TCx (YES in step 313), the low speed operation of the indoor fan 12 is continued (step 314).

  Thereafter, when the temperature TC of the indoor heat exchanger 9 rises and exceeds the set value TCx (NO in step 313), the speed of the indoor fan 12 is rapidly increased, and the operation shifts to the heating operation (step 315).

  Thus, when the temperature TC of the indoor heat exchanger 9 is sufficiently increased, the speed of the indoor fan 12 is rapidly increased, so that a large amount of hot air having a sufficiently high temperature is blown into the room for heating. Quick and comfortable heating is implemented. Thereafter, the operating frequency F (operating capacity) of the compressor 40 is controlled according to the air conditioning load (difference between the indoor temperature TA and the target value), and the speed of the indoor fan 12 is adjusted according to the remote control operation.

  During the heating operation, when an instruction to stop heating is issued by remote control operation (YES in step 316), the operation of the compressor 40, the outdoor fan 46, and the indoor fan 12 is stopped, and the four-way valve 43 is returned, The heating operation is stopped (step 317).

  If the heating preheating condition is not satisfied during the preheating operation (NO in step 301), the preheating operation is prohibited at that time (step 318). Also in this case, the “preheating” display on the display unit 20 is canceled (step 319).

  As described above, when the preheating condition for heating is established, the preheating operation for maintaining the temperature TC of the indoor heat exchanger 9 within a certain range by forming the heating flow path of the heat pump refrigeration cycle while operating the compressor 40 at a low capacity. After that, when an instruction to start heating is received, the capacity of the compressor 40 is increased, and the indoor fan 12 is operated at a low speed until the detected temperature TC of the heat exchanger temperature sensor reaches the set value TCx. When the detected temperature TC exceeds the set value TCx, the speed of the indoor fan 12 is rapidly increased to shift to the heating operation, thereby enabling rapid and high air volume heating.

  In addition, during the preheating operation, a short circuit is formed in which the blown air circulates through the shortest path from the outlet 4 of the indoor unit 1 to the upper surface inlet 2, so that the heat is gradually radiated around the indoor unit 1. This radiation can improve the heating efficiency.

  In particular, in a state where the refrigerant solubility (dilution degree) immediately after the start of the compressor 40 is high, it is possible to secure an oil film on the sliding portion of the compressor 40 by operating the compressor 40 with a higher capacity than a low capacity. This can prevent the compressor 40 from being locked or damaged. When the set time t1x elapses from the start and enters a stable state where the refrigerant solubility (dilution degree) is increased, the compressor 40 is operated with a low capacity, so that power consumption can be reduced and an energy saving effect can be obtained.

  In the embodiment described above, it is determined that the preheating condition for heating is satisfied when the indoor temperature TA is 10 ° C. or lower and the outdoor temperature TO is 15 ° C. or lower. When it is determined, control for determining that the preheating condition for heating is satisfied may be added even when the remaining time until the heating start time falls within a predetermined time.

  When the remaining time until the heating start time falls within the predetermined time, it is judged that the preheating condition for heating is satisfied and the preheating operation is started, so that the preheating necessary for heating is completed in the shortest possible time. be able to. Wasteful preheating is eliminated and power consumption can be reduced in this respect.

  Further, in the above embodiment, during the preheating operation, the operation frequency F2 is initially set to operate the compressor 40 with a higher capacity than the low capacity, and then the operation frequency F1 (<F2) is set to set the compressor 40. In addition to the low-capacity operation, the compressor 40 may be initially operated by two cylinders and then operated by one cylinder. By the first two-cylinder operation, the temperature of the compressor 40 in a low temperature state quickly rises and the refrigerant solubility (dilution degree) decreases, and an oil film on the sliding portion of the compressor 40 can be ensured reliably.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.

  DESCRIPTION OF SYMBOLS 1 ... Indoor unit, 2 ... Upper surface inlet, 3 ... Front inlet, 4 ... Air outlet, 6 ... Movable panel, 6a ... Transmission display part, 9 ... Indoor heat exchanger, 12 ... Indoor fan, 20 ... Display unit, DESCRIPTION OF SYMBOLS 40 ... Compressor, 41, 42 ... Cylinder, 45 ... Outdoor heat exchanger, 46 ... Outdoor fan, 48 ... Switching valve, 60 ... Indoor control part, 65 ... Drive circuit, 100 ... Remote control, 203 ... Outdoor control part, 206 ... Inverter

Claims (4)

It is possible to form a heating channel that has two cylinders and allows the refrigerant discharged from the compressor, which can be switched between 2-cylinder operation and 1-cylinder operation, to return to the compressor through the indoor heat exchanger, decompressor, and outdoor heat exchanger. Heat pump refrigeration cycle,
An indoor fan for circulating indoor air through the indoor heat exchanger;
When the preheating condition for heating based on the indoor temperature and the outdoor temperature is established, the indoor fan is operated at an extremely low speed, the compressor is first operated at a capacity higher than the low capacity, and the one cylinder is operated thereafter. Control means for operating at a low capacity and performing a preheating operation for heating the indoor heat exchanger while forming the heating flow path ;
An air conditioner comprising: The Following preheating operation, to increase the ability of the compressor, and the detected temperature of the heat exchanger temperature sensor for the indoor fan low speed operation or stop until it reaches the set value greater than the detected temperature set value Control means for rapidly increasing the speed of the indoor fan and shifting to heating operation,
The air conditioner according to claim 1, further comprising: When the indoor temperature and the outdoor temperature are each equal to or lower than a predetermined value, or when the remaining time until the predetermined heating start time is within a predetermined time, the control means for performing the preheating operation is that the preheating condition for heating is satisfied. The indoor fan is operated at a very low speed, the compressor is first operated at a capacity higher than the low capacity, and then the one cylinder is operated at a low capacity, and then the heating is performed. The air conditioner according to claim 1 or 2, wherein a preheating operation is performed to maintain a detected temperature of the indoor heat exchanger in a certain range while forming a flow path.   The air conditioner according to claim 3, further comprising a remote control type operating device having a function of setting the heating start time at least twice a day.

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