Patent Description:
In order to suppress global warming, a coolant of an air conditioner is required to be switched to a coolant with a low global warming potential (GWP). Under such a circumstance, PTL <NUM> discloses an air conditioner using a flammable coolant such as hydrocarbon as the coolant with a low GWP. This air conditioner stops a flow of the coolant by a shutoff valve, and avoids danger of fire. This air conditioner includes sensors, each of which detects a leak of the coolant, in a heat exchange chamber and a machine chamber in an indoor unit. The air conditioner further includes, in the indoor unit, such a shutoff valve that shuts off a flow of the coolant between the indoor unit and an outdoor unit. When the leak of the coolant in the indoor unit is detected by the above-described sensors, the air conditioner stops the flow of the coolant by the above-described shutoff valve, and avoids the danger of fire. Japanese Patent document <CIT> describes another exemplary air conditioner comprising flammable refrigerant and an air outlet with a flap controlled to adjust an orientation of the air blown out into a room.

The present invention provides an air conditioner that does not form a flammable region immediately below the indoor unit even if the coolant leaks in the indoor unit during thermo OFF of the indoor unit.

An air conditioner in the present invention is provided in claim <NUM> and it has a refrigeration cycle in which an indoor heat exchanger of an indoor unit and an outdoor heat exchanger of an outdoor unit, a compressor, and a throttle device are connected via pipes to one another in a closed circuit, the refrigeration cycle using a flammable coolant, the air conditioner including: a blower fan that receives air that has passed through the indoor heat exchanger and blows the air to an air outlet of the indoor unit; a flap that adjusts an orientation of the air blown out from the air outlet into a room; and a control device that controls the blower fan and the flap, wherein the control device closes the flap in an event of stopping the blower fan while the air conditioner keeps running, and, when the control device determines that the flammable coolant has leaked based on an output of the leak detection sensor, the control device is configured to operate the blower fan, and to control the flap to turn an orientation of the air upward with respect to a horizontal plane.

The air conditioner in the present invention closes the flap when the blower fan stops. When the flammable coolant has leaked in the indoor unit, the flap can suppress a phenomenon that the flammable coolant leaks into the room from the air outlet and forms a flammable region containing the flammable coolant in a high concentration. The air conditioner can further enhance the safety when the flammable coolant leaks.

An air conditioner according to a first embodiment of the invention is an air conditioner having a refrigeration cycle in which an indoor heat exchanger of an indoor unit and an outdoor heat exchanger of an outdoor unit, a compressor, and a throttle device are connected via pipes to one another in a closed circuit, the refrigeration cycle using a flammable coolant, the air conditioner including: a blower fan that receives air that has passed through the indoor heat exchanger and blows the air to an air outlet of the indoor unit; a flap that adjusts an orientation of the air blown out from the air outlet into a room; and a control device that controls the blower fan and the flap, wherein the control device closes the flap in an event of stopping the blower fan while the air conditioner keeps running. The air conditioner closes the flap when the blower fan of the indoor unit stops. When the flammable coolant has leaked in the indoor unit, the air conditioner closes the flap, and can thereby suppress a phenomenon that the flammable coolant leaks into the room from the air outlet and forms a flammable region containing the flammable coolant in a high concentration. The air conditioner can further enhance safety when the flammable coolant leaks.

In addition to the feature above, includes a leak detection sensor, and when the control device determines that the flammable coolant has leaked based on an output of the leak detection sensor, the control device may operate the blower fan, and may control the flap to turn an orientation of the air upward with respect to a horizontal plane. The control device turns the flap upward with respect to the horizontal plane in an event where the leak detection sensor has detected the flammable coolant. Thus, the air conditioner will suppress the flammable region from being formed immediately below the indoor unit, will diffuse the flammable coolant, and can further enhance the safety at the time when the flammable coolant leaks.

In particular, in an unclaimed exemplary embodiment of the present disclosure, the flap may open and close downward, and the flap may be provided with a structure of completely closing the air outlet of the indoor unit in an event of closing. In the indoor unit including the flap that opens and closes downward, a tip end of the flap is in contact with a bottom surface of the indoor unit. Therefore, if the air outlet cannot be completely closed, the flammable coolant with a high concentration leaks into the room from the bottom surface of the indoor unit. The air conditioner includes the flap having a length to make it possible to completely close the air outlet, will be thereby able to suppress the flammable region from being formed immediately below the indoor unit, and can further enhance the safety at the time when the flammable coolant leaks.

In particular, in addition to the feature of the air conditioner of the first embodiment of the invention, in an air conditioner according to a second preferred embodiment of the invention, the indoor unit may have a display unit, the display unit indicating that the air conditioner is under operation when the blower fan stops while the air conditioner keeps running. For example, a front panel of the indoor unit may include a display indicating that the air conditioner is under operation. The display can notify a user of a state in which the air conditioner is under operation even when the fan stops and the flap is closed while the air conditioner keeps running. The air conditioner can prevent a decrease of comfortability of the user due to safety measures at the time when the flammable coolant leaks.

In particular, in addition to the feature of the air conditioner of any one of the first and second embodiments of the invention, in an air conditioner according to a third preferred embodiment of the invention, the control device may cause a remote controller for operating the air conditioner to indicate that the air conditioner is under operation, when the blower fan stops while the air conditioner keeps running. Even when the fan stops and the flap is closed while the air conditioner keeps running, the control device causes the remote controller to indicate that the air conditioner is under operation, and can thereby notify the user of an operation state. The air conditioner can prevent the decrease of comfortability of the user due to the safety measures at the time when the flammable coolant leaks.

In particular, in addition to the feature of the air conditioner of any one of the first to third embodiments of the invention, in an air conditioner according to a fourth preferred embodiment of the invention, the control device may cause a communication terminal other than the remote controller to display that the air conditioner is under operation when the blower fan stops while the air conditioner keeps running. Even when the fan stops and the flap is closed while the air conditioner keeps running, the control device causes, for example, a personal communication terminal to display that the air conditioner is under operation, and can thereby notify the user of an operation state. The air conditioner can prevent the decrease of comfortability of the user due to the safety measures at the time when the flammable coolant leaks.

Exemplary embodiments of the present invention will be described below with reference to the drawings. However, detailed descriptions more than necessary may be omitted. For example, a detailed description of a matter which is already well-known, or a repetitive description for a substantially identical configuration may be omitted.

Note that the attached drawings and the following description are provided for those skilled in the art to fully understand the present invention, and are not intended to limit the subject matter as described in the appended claims.

<FIG> illustrates a cross section of an indoor unit of an air conditioner in a first exemplary embodiment of the present invention.

The air conditioner uses a coolant gas having flammability, for example, uses a flammable coolant composed of propane (R290), isobutane (R600a), ethane (R170), or the like. Indoor unit <NUM> includes: indoor heat exchanger <NUM>; and cross flow fan <NUM>. Air is introduced from suction port <NUM>, passes through indoor heat exchanger <NUM> and cross flow fan <NUM>, and is blown out from air outlet <NUM>. In order to adjust a direction of blowing out air, indoor unit <NUM> includes flap <NUM> in the vicinity of air outlet <NUM>. The air conditioner has a refrigeration cycle including: indoor heat exchanger <NUM> of the indoor unit; and an outdoor heat exchanger of an outdoor unit, a compressor, and a throttle device; and pipes which connect these to one another.

Indoor unit <NUM> includes a control device that stops cross flow fan <NUM> in a case of a thermo OFF state even while the air conditioner keeps running. In that event, the control device closes flap <NUM> at the same time. Even when the flammable coolant has leaked in indoor unit <NUM> in the event where cross flow fan <NUM> of indoor unit <NUM> stops, the air conditioner can suppress a phenomenon that the flammable coolant leaks into a room from indoor unit <NUM> and forms a flammable region immediately below indoor unit <NUM>, the flammable region containing the flammable coolant in a high concentration.

Moreover, the control device always closes flap <NUM> in a state where cross flow fan <NUM> stops. The flammable coolant that has leaked in indoor unit <NUM> is prone to be retained in indoor unit <NUM>. Thus, leak detection sensor <NUM> can detect the flammable coolant in a short time.

In the event where the flammable coolant is detected by leak detection sensor <NUM>, the control device may operate cross flow fan <NUM> and may turn an orientation of flap <NUM> upward with respect to a horizontal plane. Thus, the flammable coolant will be diffused, and the flammable region is suppressed from being formed immediately below indoor unit <NUM>.

Hence, the air conditioner can further enhance safety when the flammable coolant leaks.

Note that indoor unit <NUM> may include a display on a panel surface in order to indicate that the air conditioner is under operation even when the fan stops. Indoor unit <NUM> may indicate, on a remote controller, that the air conditioner is under operation. Indoor unit <NUM> may transmit a notice that the air conditioner is under operation to a personal communication terminal (for example, a smartphone or a tablet). Thus, the air conditioner can notify a user of an operation state thereof even when the fan stops and the flap is closed while the air conditioner keeps running. The air conditioner can prevent the decrease of comfortability of the user due to the safety measures at the time when the flammable coolant leaks.

<FIG> illustrates a cross section of an indoor unit of an air conditioner in an unclaimed exemplary embodiment of the present disclosure.

Unlike the indoor unit in the first exemplary embodiment of the invention, indoor unit <NUM> includes downward flap <NUM> that opens and closes downward. Downward flap <NUM> is provided with a length to completely close air outlet <NUM> in the event of closing. In indoor unit <NUM>, a tip end of flap <NUM> comes into contact with a bottom surface of indoor unit <NUM>. If flap <NUM> cannot completely close air outlet <NUM>, the flammable coolant with a high concentration leaks from the bottom surface of indoor unit <NUM>. Indoor unit <NUM> includes flap <NUM> with a length to make it possible to close air outlet <NUM>. Thus, the air conditioner will be able to suppress the flammable region from being formed immediately below the indoor unit, and the safety at the time when the flammable coolant leaks can be further enhanced.

Claim 1:
An air conditioner including a refrigeration cycle in which an indoor heat exchanger (<NUM>) of an indoor unit (<NUM>) and an outdoor heat exchanger of an outdoor unit, a compressor, and a throttle device are connected via pipes to one another in a closed circuit, the refrigeration cycle comprising a flammable coolant, the air conditioner comprising:
a blower fan (<NUM>) for receiving air that has passed through the indoor heat exchanger (<NUM>) and blowing the air to an air outlet (<NUM>) of the indoor unit (<NUM>);
a flap (<NUM>) for adjusting an orientation of the air blown out from the air outlet (<NUM>) into a room; and
a control device configured to control the blower fan (<NUM>) and the flap (<NUM>),
wherein the control device is further configured to close the flap (<NUM>) in an event of stopping the blower fan (<NUM>),
wherein the indoor unit (<NUM>) includes a leak detection sensor (<NUM>),
characterized in that the control device is configured to close the flap (<NUM>) in the event of stopping the blower fan (<NUM>) while the air conditioner keeps running, and,
when the control device determines that the flammable coolant has leaked based on an output of the leak detection sensor (<NUM>), the control device is configured to operate the blower fan (<NUM>), and to control the flap (<NUM>) to turn an orientation of the air upward with respect to a horizontal plane.