Patent Description:
PTL <NUM> discloses an air conditioner including a sensor that detects a refrigerant leak, a heat exchange chamber, a machine chamber, and a drain pan extending from a lower part of the heat exchange chamber to a lower part of the machine chamber. The sensor is disposed near the drain pan. The refrigerant leaking from a heat exchanger flows along the drain pan and is detected by the sensor. The refrigerant leaking from a refrigerant pipe disposed in the machine chamber flows toward the lower part of the machine chamber, and is similarly detected by the sensor.

PTL <NUM> describes an air conditioner using a combustible HFC refrigerant.

An indoor unit of a wall-hung type includes a pipe connector that connects a refrigerant pipe attached to an indoor heat exchanger to a refrigerant pipe attached to an outdoor heat exchanger. When the indoor unit is installed by a left-hand pipe connection method, the pipe connector is located between the back of the indoor unit and the wall surface. The left-hand pipe connection method is a pipe connection method by which the refrigerant pipe is led into the indoor unit through a pipe attachment hole formed on the left side of the indoor unit. When the refrigerant leaks from the pipe connector, a leak detection sensor disposed in the indoor unit is unable to detect the refrigerant leak, which is a problem.

The present invention has been made in view of the above circumstances, and provides an air conditioner that can detect a refrigerant leak even when the refrigerant leak occurs between the back of an indoor unit and the wall surface.

An air conditioner according to the present invention is defined by the appended claims. It includes: an indoor heat exchanger in an indoor unit; an outdoor heat exchanger in an outdoor unit; a pipe connector connecting a refrigerant pipe attached to the indoor heat exchanger to a refrigerant pipe attached to the outdoor heat exchanger; and a flammable refrigerant filling each of the refrigerant pipes. In the air conditioner, the indoor unit includes: an air blow circuit housing the indoor heat exchanger; an underframe; a pipe connection housing section located on a back surface of the underframe of the indoor unit, the pipe connection housing section housing the pipe connector; and a leak detection sensor that detects a leak of the flammable refrigerant, the leak detection sensor being disposed in the air blow circuit, and the indoor unit further includes a communication path communicatively connecting the air blow circuit to the pipe connection housing section.

According to the air conditioner of the present invention, when the indoor unit of a wall-hung type is installed by a left-hand pipe connection method and the flammable refrigerant leaks from the pipe connector in such an installation condition, the flammable refrigerant flows through the communication path to reach the leak detection sensor in the air blow circuit. The air conditioner is, therefore, able to detect a refrigerant leak from the pipe connector, thus offering high safety at the occurrence of a refrigerant leak.

Exemplary embodiments will now be described in detail with reference to the drawings. It should be noted that excessively detailed description may be skipped. For example, detailed description of known matters or duplicated description of substantially identical configurations may be avoided.

The accompanying drawings and the following description are provided to allow those skilled in the art to sufficiently understand the present disclosure, and are not intended to limit the subject matter described in the claims.

<FIG> is a schematic side view of an internal configuration of indoor unit <NUM> of an air conditioner according to a first exemplary embodiment of the present invention. The first exemplary embodiment will hereinafter be described with reference to <FIG>.

The air conditioner according to the present exemplary embodiment is an air conditioner using a flammable refrigerant gas, e.g., a flammable refrigerant made of propane (R <NUM>), isobutane (R 600a), ethane (R <NUM>), or the like.

Indoor unit <NUM> of the air conditioner according to the present exemplary embodiment includes indoor heat exchanger <NUM>, a blower fan, machine chamber <NUM>, underframe <NUM>, and outer panel <NUM>.

Indoor heat exchanger <NUM> is connected to an outdoor heat exchanger, a compressor, and a throttle device that are included in an outdoor unit, via refrigerant pipes. A refrigerant pipe attached to indoor heat exchanger <NUM> and a refrigerant pipe attached to the outdoor heat exchanger are connected to each other by pipe connector <NUM>. The refrigerant pipe attached to the outdoor heat exchanger is connected to the outdoor unit via outdoor unit connection <NUM>.

Machine chamber <NUM> houses a fan motor, a control board that controls indoor unit <NUM>, and the like.

Indoor heat exchanger <NUM>, the blower fan, and machine chamber <NUM> are placed in underframe <NUM>. Underframe <NUM> includes air blow circuit <NUM> housing the blower fan and indoor heat exchanger <NUM>, and pipe connection housing section <NUM> housing pipe connector <NUM>.

Indoor unit <NUM> includes leak detection sensor <NUM> that detects a leak of the flammable refrigerant, leak detection sensor <NUM> being disposed in air blow circuit <NUM>. According to the present exemplary embodiment, leak detection sensor <NUM> is provided near brazed portion <NUM> of indoor heat exchanger <NUM>, specifically, provided below brazed portion <NUM> of indoor heat exchanger <NUM>. Brazed portion <NUM> of indoor heat exchanger <NUM> is apt to be corroded or damaged. Disposing leak detection sensor <NUM> near brazed portion <NUM> of indoor heat exchanger <NUM> improves safety at the occurrence of a refrigerant leak.

Pipe connection housing section <NUM> is at the back of underframe <NUM>. Underframe <NUM> includes partition <NUM> that partitions air blow circuit <NUM> off from pipe connection housing section <NUM>. Pipe connector <NUM> connects the refrigerant pipe attached to indoor heat exchanger <NUM> to the refrigerant pipe attached to the outdoor heat exchanger. When indoor unit <NUM> is installed by a left-hand pipe connection method, pipe connection housing section <NUM> houses pipe connector <NUM> therein.

Indoor unit <NUM> includes communication path <NUM> provided between air blow circuit <NUM> and pipe connection housing section <NUM> to connect them to each other. When the refrigerant leaks in pipe connection housing section <NUM>, the refrigerant is allowed to flow through communication path <NUM> to reach air blow circuit <NUM>. Communication path <NUM> may be provided in partition <NUM> between air blow circuit <NUM> and pipe connection housing section <NUM>. Communication path <NUM> may be formed in such a way as to penetrate machine chamber <NUM>. It is preferable that an opening of communication path <NUM> that is closer to air blow circuit <NUM> be located near leak detection sensor <NUM>.

Indoor unit <NUM> has pipe outlet hole <NUM> through which the refrigerant pipe emerges from indoor unit <NUM>. It is preferable that the flow path area of communication path <NUM> be larger than the area of pipe outlet hole <NUM>. In this configuration, the refrigerant leaking in pipe connection housing section <NUM> flows into air blow circuit <NUM> rather than flowing out of indoor unit <NUM>, thus allowing leak detection sensor <NUM> provided in air blow circuit <NUM> to quickly detect the leaking refrigerant. This further improves safety at the occurrence of a refrigerant leak.

Outer panel <NUM> is formed into a shape slightly larger than underframe <NUM>, and is installed in such a way as to cover underframe <NUM>. In the present exemplary embodiment, underframe <NUM> and outer panel <NUM> are installed with almost no gap formed therebetween.

Operations and effects of the air conditioner configured in the above manner will hereinafter be described.

In the air conditioner of the present exemplary embodiment, the flammable refrigerant may leak from brazed portion <NUM> of indoor heat exchanger <NUM>. Brazed portion <NUM> of indoor heat exchanger <NUM>, when corroded or damaged, tends to cause a refrigerant leak. Because the flammable refrigerant has a specific gravity larger than that of air, the refrigerant, once it leaks out, flows downward from brazed portion <NUM> of indoor heat exchanger <NUM>. The refrigerant flowing downward reaches leak detection sensor <NUM> provided near the brazed portion <NUM> of indoor heat exchanger <NUM>, specifically, provided below brazing portion <NUM> of indoor heat exchanger <NUM>, and consequently leak detection sensor <NUM> detects the leaking refrigerant.

As described above, pipe connector <NUM> of the present exemplary embodiment connects the refrigerant pipe attached to indoor heat exchanger <NUM> to the refrigerant pipe attached to the outdoor heat exchanger in the air conditioner. When the flammable refrigerant leaks from pipe connector <NUM>, the leaking flammable refrigerant fills pipe connection housing section <NUM>, thus flowing through communication path <NUM> to reach air blow circuit <NUM>. The opening of communication path <NUM> that is closer to air blow circuit <NUM> is located near leak detection sensor <NUM>. The flammable refrigerant having passed through communication path <NUM> reaches leak detection sensor <NUM>. Hence, leak detection sensor <NUM> detects the leaking refrigerant.

In this manner, the air conditioner according to the present exemplary embodiment allows detection of the flammable refrigerant leaking from brazed portion <NUM> of indoor heat exchanger <NUM> and detection of the flammable refrigerant leaking from pipe connector <NUM> as well, and therefore can further improve safety at the time of occurrence of a refrigerant leakage. In addition, because one leak detection sensor <NUM> is able to detect refrigerant leaks of both cases, the manufacturing cost of the air conditioner can be reduced.

The air conditioner according to the present exemplary embodiment includes indoor heat exchanger <NUM> in indoor unit <NUM>, the outdoor heat exchanger in the outdoor unit, pipe connector <NUM> connecting the refrigerant pipe attached to indoor heat exchanger <NUM> to the refrigerant pipe attached to outdoor heat exchanger, and the flammable refrigerant filling each of the refrigerant pipes. In the air conditioner, indoor unit <NUM> includes air blow circuit <NUM> housing indoor heat exchanger <NUM>, pipe connection housing section <NUM> located on the back of the underframe <NUM> of indoor unit <NUM>, pipe connection housing section <NUM> housing pipe connector <NUM>, and leak detection sensor <NUM> that detects a leak of the flammable refrigerant, leak detection sensor <NUM> being disposed in air blow circuit <NUM>, and indoor unit <NUM> further includes communication path <NUM> that communicatively connects fair blow circuit <NUM> to pipe connection housing section <NUM>.

When indoor unit <NUM> is installed by a left-hand pipe connection method, pipe connector <NUM> is housed in pipe connection housing section <NUM>. When the flammable refrigerant leaks from pipe connector <NUM>, the flammable refrigerant flows through communication path <NUM> to reach leak detection sensor <NUM> in indoor unit <NUM>. The air conditioner is thus able to detect the refrigerant leak and further improve safety at the occurrence of the refrigerant leak.

As stated in the description of the present exemplary embodiment, leak detection sensor <NUM> may be provided near brazed portion <NUM> of indoor heat exchanger <NUM>.

Brazed portion <NUM> of indoor heat exchanger <NUM> is apt to be corroded or damaged. Disposing leak detection sensor <NUM> near brazed portion <NUM> of indoor heat exchanger <NUM> allows quick detection of a refrigerant leak, thus improving safety at the occurrence of a refrigerant leak.

In the present exemplary embodiment, indoor unit <NUM> includes pipe outlet hole <NUM> through which the refrigerant pipe connected to pipe connector <NUM> passes. The flow path area of communication path <NUM> may be larger than the area of pipe outlet hole <NUM>.

This gives the flammable refrigerant leaking in pipe connection housing section <NUM> a tendency that the flammable refrigerant flows into air blow circuit <NUM> rather than flowing out of indoor unit <NUM>. Leak detection sensor <NUM> provided in air blow circuit <NUM> is capable of quickly detecting a leak of the flammable refrigerant. This further improves safety at the occurrence of a refrigerant leakage.

An air conditioner according to a second exemplary embodiment of the present invention will be described. The second exemplary embodiment will be described, with focus placed on what is different from the first exemplary embodiment. In the second exemplary embodiment, constituent elements identical or equal with those of the first exemplary embodiment will be denoted by the same reference numerals. From the description of the second embodiment, a description overlapping the description of the first exemplary embodiment is omitted.

<FIG> is a schematic front view of an internal configuration of indoor unit <NUM> of the air conditioner according to a second exemplary embodiment. The second exemplary embodiment will hereinafter be described with reference to <FIG>.

Indoor unit <NUM> includes partition <NUM> that partitions air blow circuit <NUM> off from pipe connection housing section <NUM>, air blow circuit <NUM> and pipe connection housing section <NUM> being included in underframe <NUM> of indoor unit <NUM>. An end surface of partition <NUM> that is closer to leak detection sensor <NUM> is at least partially opened. In the second exemplary embodiment, indoor unit <NUM> has gap <NUM> of <NUM> or more on at least a part of a space between partition <NUM> and outer surface panel <NUM>, the gap serving as communication path <NUM>. It is preferable that gap <NUM> be provided on the side closer to leak detection sensor <NUM> in indoor unit <NUM>. In the present second exemplary embodiment, gap <NUM> is provided on the right side of indoor unit <NUM> in a front view thereof.

It is preferable that the flow path area of communication path <NUM>, i.e., gap <NUM> be larger than the area of pipe outlet hole <NUM>. This gives the flammable refrigerant leaking in pipe connection housing section <NUM> a tendency that the flammable refrigerant flows into air blow circuit <NUM> rather than flowing out of indoor unit <NUM>. Leak detection sensor <NUM> provided in air blow circuit <NUM> is capable of quickly detecting a leak of the flammable refrigerant. This further improves safety at the occurrence of a refrigerant leakage.

Pipe connector <NUM> connects the refrigerant pipe attached to indoor heat exchanger <NUM> to the refrigerant pipe attached to the outdoor heat exchanger in the air conditioner. When the flammable refrigerant leaks from pipe connector <NUM> of the present exemplary embodiment, the leaking flammable refrigerant fills pipe connection housing section <NUM>, flows through gap <NUM> between underframe <NUM> and outer panel <NUM> and through the end surface of partition <NUM> that is closer to leak detection sensor <NUM>, and finally reaches leak detection sensor <NUM> in air blow circuit <NUM>.

Claim 1:
An air conditioner comprising:
an indoor heat exchanger (<NUM>) in an indoor unit (<NUM>);
an outdoor heat exchanger in an outdoor unit;
a pipe connector (<NUM>) connecting a refrigerant pipe attached to the indoor heat exchanger (<NUM>) to a refrigerant pipe (<NUM>) attached to the outdoor heat exchanger; and
a flammable refrigerant filling each of the refrigerant pipes,
wherein the indoor unit (<NUM>) includes:
an air blow circuit (<NUM>) housing the indoor heat exchanger (<NUM>);
an underframe (<NUM>);
a pipe connection housing section (<NUM>) located on a back surface of the underframe (<NUM>) of the indoor unit, the pipe connection housing section (<NUM>) housing the pipe connector (<NUM>); and
a leak detection sensor (<NUM>) that detects a leak of the flammable refrigerant, the leak detection sensor (<NUM>) being disposed in the air blow circuit (<NUM>), and
wherein the indoor unit (<NUM>) further includes a communication path (<NUM>) having a flow path area and communicatively connecting the air blow circuit (<NUM>) to the pipe connection housing section (<NUM>).