Abstract: In the air conditioner of the present invention, both the normal cooling mode operation, in which refrigerant discharged from the compressor 1 is made to flow in the condenser 2, and the heating mode operation conducted by the hot gas bypass, in which refrigerant is made to bypass the condenser and directly flow in the evaporator 4 via the throttle 17, can be conducted. Before this heating mode operation, after the compressor is turned on for a predetermined period of time in the cooling mode, the compressor is turned off for a predetermined period of time, so that refrigerant residing in the condenser can be recovered into the hot gas cycle, and then a hot gas operation, which is the heating mode, is conducted.

Abstract: In a vehicle air conditioner, a refrigerant cycle system is constructed to switch a cooling refrigerant cycle where an interior heat exchanger is used as an evaporator, and a hot gas heater cycle where the interior heat exchanger is used as a radiator. Further, it is determined whether the interior heat exchanger has a quantity of retained water in a heating mode due to the hot gas heater cycle. When it is determined that the quantity of retained water is in the interior heat exchanger in the heating mode, operation of a compressor of the refrigerant cycle system is intermittently controlled so that temperature of air blown from the interior heat exchanger becomes lower than temperature of a vehicle windshield.

Abstract: A front end structure according to the present invention is constituted such that a front end panel (400) is configured of a duct structure for preventing the air introduced from a grille opening (452) from bypassing a condenser (200) and a radiator (100), and a fan unit (300) is arranged on the most upstream side portion of the structure. As a result, without the need to provide parts making up a duct structure, fresh air low in temperature can be blown, while at the same time, the air that has passed through the condenser (200) can be prevented from bypassing the radiator (100). Thus, the heat releasing capacity of the condenser (200) and the radiator (100) can be improved while at the same time improving the hermetic sealing between the condenser (200) and the radiator (100) with simple means.

Abstract: An engine cooling apparatus suitable for use in a vehicle shortens engine warm-up time without decreasing the heat-radiation capacity of a radiator. A shroud is disposed between a radiator and a water-cooled engine. A first air passage for blowing air toward the engine and its auxiliaries is formed in the upper side of the shroud, and a second air passage for discharging air having passed through the radiator to outside the engine compartment is formed in the lower side of the shroud. Accordingly, air is prevented from directly striking the engine and from passing around to the upstream side of the radiator through gaps between the walls of the engine compartment and the radiator. Thus the engine warm-up time is shortened without reducing the heat-radiation capacity of the radiator.