In general, air-conditioning devices comprise an internal unit and an external unit, and the heat drawn from the internal unit during cooling process is discharged to the outer environment by the external unit. In portable (transportable) air-conditioning devices, cooling process is usually performed by discharging the heat drawn from the ambiance to the outer environment by means of a vent extending outdoors through an aperture opened on a window or a wall. However, the vent structure that enables heat to be discharged to the outer environment, restricts transportability of the air-conditioning device. In addition, portable air- conditioning devices are not preferred by many users since an aperture to be opened on a window or a wall for the vent needs to be formed suitably, in order to obtain an efficient cooling performance by providing insulation between the ambiance that requires cooling and the outer environment. This problem can be eliminated with applications in which a part of such residual heat is stored in a thermal storage member without discharging. In portable air- conditioning devices, storage of residual heat which has to be discharged to the outer environment by a condenser using PCM packages made of phase change material (PCM) with high heat storage capacity, is known. Phase change process is completed after storing a specific amount of residual heat and the PCM packages become incapable of heat storage. In this case, PCM packages require being subjected to a regeneration process by means of cooling. The PCM packages should be removed and placed in a cooler- freezer device for the regeneration process. The duration in which the PCM packages store a certain amount of heat, varies according to ambient conditions. Since the environmental parameters such as temperature and humidity would present varying durations, it is difficult for a user to know when the PCM packages should be cooled. Due to the difficulty, many users do not replace the PCM packages in due time, consequently decreasing the cooling performance of the portable air-conditioning device.

The patent application no. DE3938875 (Al), discloses a portable air-conditioning device in which discharging of heat is eliminated by means of storing thermal energy on the phase change material. The patent application no. WO2017137327 (Al) relates to a transportable air-conditioning device. The aim of the present invention is to realize a portable air-conditioning device in which the PCM packages are enabled to be replaced in due time by performing precise temperature measurements.

The portable air-conditioning device provided to achieve the aim of the present invention is disclosed in the claims.

In the portable air-conditioning device PCM packages (phase change material packages) are used, storing residual heat discharged by the condenser. The PCM packages become unable to store heat after being used for a certain duration, so they should be removed for the regeneration (cooling) process from the heat storage chamber in which they are disposed. The portable air-conditioning device of the invention comprises a temperature sensing thermistor placed in a heat storage chamber or on a PCM package. The control unit evaluates the temperature information received from the thermistor, determines completion of the usage time of a PCM package when the temperature of the heat storage chamber or a PCM package exceeds a given value, and enables the user to be alerted by a lighting display and/or an alarm for cooling the PCM package or for replacing it with an already cooled one.

The portable air-conditioning device provided to achieve the aim of the present invention is illustrated in the accompanying drawings, wherein:

Figure 1 is a perspective view of in the portable air-conditioning device.

Figure 2 is a perspective view of a PCM package and a thermistor placed thereon. Figure 3 is a perspective view of a PCM package provided with a metal sheet on one of its surfaces, and the thermistor placed thereon.

Figure 4 is a perspective view of a PCM package provided with a metal probe on one of its surfaces, and the thermistor placed thereon.

Figure 5 is a perspective view of a metal probe. Figure 6 is a schematic view of a holder and a spring enabling the thermistor to be attached on a PCM package.

The elements in the figures are numbered individually and the correspondence of these numbers are given hereinafter.

1. Portable air-conditioning device 2. Compressor 3. Condenser

4. Evaporator

5. PCM package

6. Thermistor

7. Metal sheet

8. Metal probe

9. Holder

10. Spring

11. Heat storage chamber The portable air-conditioning device (1), comprises a compressor (2) enabling the cooling cycle, a condenser (3) enabling heat to be discharged to the outer environment by condensing a refrigerant, an evaporator (4) drawing heat from the ambiance by evaporating the coolant and enabling cooling of the ambient air, at least one phase change material (PCM) package (5) (PCM package (5) for short) obtained by packing phase change material (PCM) with high heat storage capacity in a plastic container (not shown in the figures), transferring and storing the heat of the condenser (3), and a heat storage chamber (11) in which the PCM packages (5) are placed.

The portable air-conditioning device (1) of the invention comprises,

- a thermistor (6) placed inside the heat storage chamber (11), for example on the internal surface of a side wall of the heat storage chamber (11) or on a PCM package (5), whose electrical resistance value changes according to the temperature value it senses, and

- a control unit (not shown in the figures) determining by evaluating the temperature information from the thermistor (6), the completion of the usage time of a PCM package (5), upon the temperature of the heat storage chamber (11) or the PCM package (5) exceeding a limit value presaved to its memory, and enabling the user to be alerted by means of visual and/or audible alert, for example by a lighting display and/or an alarm for cooling the PCM package (5) or for replacing it with an already cooled PCM package (5).

In an embodiment of the invention, the thermistor (6) is of the NTC (Negative Temperature Coefficient) type, and its resistance decreases as the temperature of the PCM package (5) increases. In an embodiment of the invention, the thermistor (6) is of the PTC (Positive Temperature Coefficient) type, and its resistance increases as the temperature of the PCM package (5) increases.

In an embodiment of the invention, the portable air-conditioning device (1) comprises a PCM package (5) shaped as a rectangular prism, and at least one metal plate (7) constituting at least one surface of the PCM package (5), on which the thermistor (6) is placed. The inner surface of the metal plate (7) contacts the phase change material, and its outer surface contacts the thermistor (6). Since thermal conductivity of the metal plate (7) is higher than the plastic container of a PCM package (5), the thermistor (6) is enabled to sense the temperature of the PCM package (5) correctly and rapidly (Figure 3).

In another embodiment of the invention, the portable air-conditioning device (1) comprises a metal probe (8) placed to the PCM package (5) by being inserted in vertical direction to one of its surfaces, whose end extending into the PCM package (5) contacts the phase change material, and on whose cap resting on a surface of the PCM package (5), is placed the thermistor (6). Thus, temperature information can be received from the phase change material disposed in the interior of the PCM package (5), increasing measurement precision (Figure 4, Figure 5).

In another embodiment of the invention, the portable air-conditioning device (1) comprises a holder (9) and a spring (10) provided in the heat storage chamber (11) or on a PCM package (5), enabling the thermistor (6) to be placed so as to continuously contact the outer surface of the PCM package (5), or the metal plate (7), or the cap of the metal probe (8), or the inner surface of the heat storage chamber (11) (Figure 6).

In another embodiment of the invention, the control unit evaluates the temperature information from the thermistor (6) and calculates the remaining usage time of a PCM package (5) until its replacement is required, and enables informing the user by means of an indicator.

In another embodiment of the invention, the control unit evaluates the temperature information from the thermistor (6) and calculates the useful lifetime of a PCM package (5) and enables informing the user by means of an indicator. The temperature of the PCM package (5) is measured by the thermistor (6), the temperature information received from the thermistor (6) is evaluated by the control unit, and an alert is signaled to the user by a lighting display and/or an alarm regarding cooling of the PCM package (5) or its replacement with an already cooled one. Thus, the portable air-conditioning device (1) is prevented from being operated with a PCM package (5) whose usage time is completed, and cooling performance is enhanced by enabling the PCM package (5) to be replaced in correct times.