JP2016038190A - Refrigeration cycle device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigeration cycle device which minimizes failure due to leak and ignition of a flammable refrigerant even when such leak and ignition occur.SOLUTION: A refrigeration cycle device includes: a refrigeration cycle filled with a flammable refrigerant; detection means detecting ignition of the flammable refrigerant leaked from the refrigeration cycle; and notification means notifying a user of the detection of the ignition when the detection means detects the ignition. The detection means detects abrupt change in a contact resistance value as ignition of the flammable refrigerant when the flammable refrigerant leaks from the refrigeration cycle and ignites.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a refrigeration cycle apparatus that uses a combustible refrigerant.

  In a refrigeration cycle mounted on an air conditioner or the like, a refrigerant that has been filled is compressed by a compressor, and the refrigerant discharged from the compressor is returned to the compressor through a condenser, a decompressor, and an evaporator.

  R32 refrigerant is known as a refrigerant used in the refrigeration cycle. R32 refrigerant has a lower global warming potential than conventional R410A refrigerant, but has combustibility (slight flammability).

JP 2002-98393 A

  An air conditioner equipped with a refrigeration cycle includes an electrical component box containing electrical components such as switch contacts in an outdoor unit, for example.

  When a combustible refrigerant such as R32 refrigerant leaks from a connection part or a joint of a pipe of a refrigeration cycle, the leaked combustible refrigerant (gas) flows into the electrical component box. The combustible refrigerant that has flowed into the electrical component box has a high concentration due to the small volume of the electrical component box, and reaches a flammable concentration (or ignition concentration).

  When the switch contact in the electrical component box is opened and closed in this state, the spark generated by the opening and closing ignites the flammable refrigerant, and the switch contact is welded or deteriorated. As it is, there is a problem in the operation control of the air conditioner.

  An object of an embodiment of the present invention is to provide a refrigeration cycle apparatus capable of minimizing problems caused by a flammable refrigerant leaking and igniting.

  The refrigeration cycle apparatus of claim 1 is a refrigeration cycle filled with a flammable refrigerant, detection means for detecting ignition of the flammable refrigerant leaked from the refrigeration cycle, and when the detection means detects ignition, that effect Informing means for informing.

The perspective view which shows the external appearance of one Embodiment. The figure which shows the refrigerating cycle of the same embodiment, an electrical component box, and a control part. The flowchart which shows the control which the control part of the embodiment performs.

  Hereinafter, an embodiment of the present invention will be described. First, the external appearance of, for example, an air conditioner that is a refrigeration cycle apparatus is shown in FIG.

  The ceiling unit mounting type (also referred to as a ceiling cassette type) indoor unit 1 includes a rectangular frame-shaped decorative panel 2 facing the indoor space, a rectangular suction panel 3 disposed inside the decorative panel 2, and the suction panel 3 Provided with a plurality of outlets 4 formed between each side of the outer peripheral edge and each side of the inner peripheral edge of the decorative panel 2.

  The main body of the indoor unit 1 is embedded in the ceiling surface of the air-conditioned room. With this embedding, the decorative panel 2, the suction panel 3, and the air outlets 4 face the indoor space of the air-conditioned room. A remote control cable 31 is led out from the main body of the indoor unit 1, and a remote control type operating device (referred to as a remote control) 30 is connected to the tip of the remote control cable 31. One end of each of the liquid side refrigerant pipe 41 and the gas side refrigerant pipe 42 is connected to a pipe connection portion of the main body of the indoor unit 1, and the other end of each of the liquid side refrigerant pipe 41 and the gas side refrigerant pipe 42 is a pipe of the outdoor unit 40. Connected to the connection.

  One end of the crossover wiring 43 is connected to the main body of the indoor unit 1, and the other end of the crossover wiring 43 is connected to the outdoor unit 40. The crossover wiring 43 includes a power supply line and a control signal line. The outdoor unit 40 incorporates an electrical component box (also referred to as a control box) 100 and is connected to a three-phase AC power supply 46 via a power line 44 and a breaker 45.

  A heat pump refrigeration cycle mounted on the indoor unit 1 and the outdoor unit 40 is shown in FIG.

  An outdoor heat exchanger 53 is connected to the discharge port of the compressor 51 via a four-way valve 52, and a packed valve 55 is connected to the outdoor heat exchanger 53 via an electric expansion valve 54. The indoor heat exchanger 8 of the indoor unit 1 is connected to the packed valve 55 via the liquid side refrigerant pipe 41, and the packed valve 56 of the outdoor unit 40 is connected to the indoor heat exchanger 8 via the gas side refrigerant pipe 42. Is connected to the pipe. The intake port of the compressor 51 is connected to the packed valve 56 through the four-way valve 52 and the accumulator 57 by piping.

  As the refrigerant charged in the heat pump refrigeration cycle, for example, R32 refrigerant having a global warming potential smaller than that of R410A is used. R32 refrigerant is flammable (slightly flammable) and easily ignites when the concentration is increased. Hereinafter, the R32 refrigerant is referred to as a combustible refrigerant.

  The compressor 51 sucks refrigerant (combustible refrigerant) from the suction port, compresses the suction refrigerant, and discharges it from the discharge port. The compressor 51 is driven at a variable speed by power supplied from an inverter. The electric expansion valve 54 is a pulse motor valve (PMV) whose opening degree changes continuously according to the number of input drive pulses. An outdoor fan 58 is disposed in the vicinity of the outdoor heat exchanger 53. An indoor fan 5 is disposed in the vicinity of the indoor heat exchanger 8.

  During cooling, the refrigerant discharged from the compressor 51 flows through the four-way valve 52 to the outdoor heat exchanger 53 as indicated by the arrows. The refrigerant flowing out of the outdoor heat exchanger 53 flows to the indoor heat exchanger 8 through the electric expansion valve 54, the packed valve 55, and the liquid side refrigerant pipe 41. The refrigerant flowing out from the indoor heat exchanger 8 is sucked into the compressor 51 through the gas side refrigerant pipe 42, the packed valve 56, the four-way valve 52, and the accumulator 57. With this refrigerant flow, the outdoor heat exchanger 53 functions as a condenser and the indoor heat exchanger 8 functions as an evaporator.

  During heating, the flow path of the four-way valve 52 is switched, so that the refrigerant discharged from the compressor 51 flows to the indoor heat exchanger 8 through the four-way valve 52, the packed valve 56, and the gas side refrigerant pipe 42. The refrigerant flowing out of the indoor heat exchanger 8 flows to the outdoor heat exchanger 53 through the liquid side refrigerant pipe 41, the packed valve 55, and the electric expansion valve 54. The refrigerant flowing out of the outdoor heat exchanger 53 is sucked into the compressor 51 through the four-way valve 52 and the accumulator 57. With this refrigerant flow, the indoor heat exchanger 8 functions as a condenser, and the outdoor heat exchanger 53 functions as an evaporator.

  A temperature sensor 61 is attached to the outdoor heat exchanger 53. A temperature sensor 62 is attached to a position of the indoor heat exchanger 8 on the cooling medium inflow side. A temperature sensor 63 is attached to the pipe between the four-way valve 52 and the accumulator 57.

  The electrical component box 100 controls the rotation speed of the compressor 51 and the outdoor fan 58, the switching of the four-way valve 52, the opening of the electric expansion valve 54, and the like, and a control board 103 (printed board) to which various temperature sensors are connected. Contained. Further, the electrical component box 100 accommodates various electrical components including the switch contacts 101r, 101s, and 101t, and also accommodates a detector (detection means) 102 that detects ignition (also referred to as ignition) of the combustible refrigerant. . The switch contacts 101r, 101s, and 101t are contacts of the switch 101 such as an electromagnetic switch, an electromagnetic contactor, and a relay, and are inserted and connected to the power line 44 from the three-phase AC power supply 46. The air conditioner It is closed during driving and is opened during non-driving. The detector 102 detects the ignition of the combustible refrigerant in the electrical component box 100.

  Specifically, the detector 102 indirectly detects the ignition of the combustible refrigerant in the electrical component box 100 from changes in the contact resistance values of the switch contacts 101r, 101s, and 101t. That is, when the combustible refrigerant in the electrical component box 100 is ignited and the switch contacts 101r, 101s, 101t are welded or deteriorated, the contact resistance values of the switch contacts 101r, 101s, 101t change abruptly. The detector 102 detects this sudden change in the contact resistance value as ignition of the combustible refrigerant.

  The detection method of the detector 102 is not limited to a method of detecting a change in the contact resistance value, a method of detecting an increase in the atmospheric temperature due to ignition with a temperature sensor, a method of detecting a pressure change due to ignition with a pressure sensor, Any of them may be used, such as a method of detecting combustion gas or smoke generated by ignition with a gas sensor or smoke sensor. Any one of these methods may be used in combination.

  As a means of detecting the rise in atmospheric temperature and pressure change due to ignition, not only the use of temperature sensors and pressure sensors, but also the use of plate-like members and coatings that melt or break under the heat and wind pressure from ignition is also possible. is there.

  The control unit 70 controls the indoor unit 1 and the outdoor unit 40. A remote controller 30 and a reset switch 71 are connected to the control unit 70. The remote controller 30 is for setting operating conditions of the air conditioner. The reset switch 71 is an automatic return type push button switch and is disposed on a control circuit board on which the control unit 70 is mounted.

The control unit 70 includes the following means (1) to (3) as main functions.
(1) First control means that closes the switch contacts 101r, 101s, and 101t when the air conditioner is in operation and opens the switch contacts 101r, 101s, and 101t when the air conditioner is not in operation.

  (2) When the detector 102 detects ignition, the operation of the air conditioner (operation of the compressor 51, the outdoor fan 58, and the indoor fan 5) is stopped, and the operation of the reset switch 71 is turned on. Second control means to be released in response to.

  (3) Notification means for notifying that when the detector 102 detects ignition, and canceling the notification in response to an ON operation of the reset switch 71.

Next, the control executed by the control unit 70 will be described with reference to the flowchart of FIG.
When the combustible refrigerant filled in the heat pump refrigeration cycle leaks from the connection part or joint of the outdoor unit 40 or its vicinity, the leaked combustible refrigerant (gas) flows into the electrical component box 100. The combustible refrigerant that has flowed into the electrical component box 100 increases in concentration because the volume of the electrical component box 100 is small, and reaches the ignition concentration (or ignition concentration).

  When the switch contacts 101r, 101s, and 101t in the electrical component box 100 are opened and closed in this state, a spark generated by the opening and closing may ignite the combustible refrigerant in the electrical component box 100. In this case, the switch contacts 101r, 101s, and 101t are welded or deteriorated, resulting in problems in subsequent operation control.

  Therefore, the control unit 70 monitors the detection result of the detector 102 (step S1). When the detector 102 detects ignition (YES in step S1), the control unit 70 forcibly stops the operation of the compressor 51, the outdoor fan 58, and the indoor fan 5 (step S2). This prevents a problem that the operation is continued with the flammable refrigerant leaking, and prevents a problem that the operation is continued in a state where the switch contacts 101r, 101s, and 101t are welded or deteriorated.

  And the control part 70 alert | reports that the combustible refrigerant | coolant leaked and ignited with this forced operation stop, for example by the character display and icon image display of the remote control 30 (step S3). By this notification, the user recognizes that the combustible refrigerant has leaked and ignited, and grasps that the cause of the operation stop is due to the leak and ignition of the combustible refrigerant. The user can request maintenance / inspection.

  Therefore, even if there is a problem that the combustible refrigerant leaks and ignites in the electrical component box 100, the problem can be minimized.

  On the other hand, the control unit 70 monitors the operation of the reset switch 71 (step S4). When the reset switch 71 is not turned on (NO in step S4), the control unit 70 continues the operation stop and notification (step S2 and step S3).

  An operator who has received a request for maintenance / inspection turns on the reset switch 71 after repairing the refrigerant leakage and replacing the electrical component in the electrical component box 100 that has been damaged by ignition with a new one.

  When the reset switch 71 is turned on (YES in step S4), the control unit 70 cancels the notification (step S5) and cancels the operation stop (step S6).

  In the above-described embodiment, the air conditioner is described as an example of the refrigeration cycle apparatus. However, as long as the apparatus is equipped with a refrigeration cycle, the present invention can be implemented not only in the air conditioner but also in other apparatuses.

  In the above embodiment, the case where the electrical component box 100 is disposed in the outdoor unit 40 has been described as an example. However, even in the case where the electrical component box 100 is disposed in the indoor unit 1, the same can be implemented.

  In the above embodiment, an example in which the switch contacts 101r, 101s, and 101t are housed in the electrical component box 100 has been described. However, the switch contacts 101r, 101s, and 101t may be disposed outside the electrical component box 100 as long as they are within the outdoor unit 40. . Of course, the detector 102 can detect the ignition of the combustible refrigerant in the switch 101 in which the switch contacts 101r, 101s, and 101t are accommodated.

  In the above embodiment, the switch contacts 101r, 101s, and 101t that are inserted and connected to the power line 44 from the three-phase AC power supply 46 have been described as examples. However, the switch contacts are not limited to this, and the printed circuit board 103 is not limited thereto. It may be a contact housed in a power relay mounted on the top.

  In the said embodiment, although R32 refrigerant | coolant was demonstrated to the example as a combustible refrigerant | coolant, when it has not only R32 refrigerant | coolant but combustibility, it can implement similarly.

  In the above embodiment, the character display or icon image display of the remote controller 30 is used as the notification means. However, in the case of an air conditioner of the type that centrally manages a plurality of indoor units 1, it is for centralized management arranged in the centralized management room. The character display and icon image display of the controller may be used as notification means. Not only character display and icon image display but also notification by voice synthesis, light emission, and light emission color change can be performed. In addition, an alarm device that issues an alarm in cooperation with other electric devices, a portable terminal such as a mobile phone device or a smartphone possessed by the user, or the like can be used as the notification means.

  In the above embodiment, the reset switch 71 is arranged on the control circuit board on which the control unit 70 is mounted. However, the reset switch 71 may be provided on the remote controller 30.

  In addition, the said embodiment and modification are shown as an example and are not intending limiting the range of invention. The novel embodiments and modifications can be implemented in various other forms, and various omissions, rewrites, and changes can be made without departing from the spirit of the invention. In these embodiments and modifications, the scope of the invention is included in the gist, and is included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 ... Indoor unit, 8 ... Indoor heat exchanger, 40 ... Outdoor unit, 41 ... Liquid side refrigerant | coolant piping, 42 ... Gas side refrigerant | coolant piping, 51 ... Compressor, 52 ... Four-way valve, 53 ... Outdoor heat exchanger, 30 ... DESCRIPTION OF SYMBOLS ... Remote control, 70 ... Control part, 71 ... Reset switch, 100 ... Electrical component box, 101 ... Switch, 101r, 101s, 101t ... Switch contact, 102 ... Detector

Claims (5)

A refrigeration cycle filled with a combustible refrigerant;
Detecting means for detecting ignition of a combustible refrigerant leaked from the refrigeration cycle;
Informing means for notifying that when the detecting means detects firing,
A refrigeration cycle apparatus comprising: Electrical component box containing switch contacts,
Further comprising
The detecting means detects ignition of the combustible refrigerant leaked from the refrigeration cycle in the electrical component box;
The refrigeration cycle apparatus according to claim 1. A switch that houses a switch contact,
Further comprising
The detection means detects ignition of the combustible refrigerant leaked from the refrigeration cycle in the switch;
The refrigeration cycle apparatus according to claim 1. Control means for stopping operation of the refrigeration cycle apparatus when the detection means detects ignition;
The refrigeration cycle apparatus according to any one of claims 1 to 3, further comprising: Reset switch,
Further comprising
The notification means releases the notification according to an operation of the reset switch;
The control means cancels the stop of the operation according to the operation of the reset switch;
The refrigeration cycle apparatus according to claim 4.

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