JP5627657B2 - Air dehumidifying device and air dehumidifying process - Google Patents

Description

  The present invention relates to an air dehumidifier of an automotive HVAC system for combined operation of a cooling system and a heat pump. Furthermore, this invention relates to the process of dehumidifying the air by which a passenger compartment is adjusted in the motor vehicle HVAC system which operate | moves as a heat pump using such an air dehumidification apparatus.

  To date, HVAC systems are typically used at ambient temperatures above 0 degrees. For vehicles that are hybrid and / or fully electrically driven, effective heating is required. Therefore, heat pump systems have been researched and developed. For efficiency, the refrigerant circuit of such systems is low in air recirculation or partial air recirculation, requiring air dehumidification before reheating the air, especially during the transition between seasons. It is also activated at ambient temperature.

  From Patent Document 1, it is known that an automotive HVAC system is provided with an integrated heat pump for cooling and heating, and the refrigerant is circulated in the circuit, thereby supplying heat for the interior of the vehicle. Can be transferred to. Heat enters directly into the airflow to the passenger compartment using an integrated heat pump.

  From Patent Document 2, a heat pump system that frequently delivers the output to air is known to have a problem related to the heat pump system in that the air supplied to the passenger compartment cannot be dehumidified and heated at the same time. This creates a situation in which the vehicle HVAC system cannot operate using recirculating air or air recirculating from the passenger compartment, respectively. Due to the lack of a dehumidifying function, undesired window glass fogging occurs. Patent Document 2 describes an HVAC system for operation that combines a cooling system and a heat pump for a vehicle having a primary circuit and a secondary passage. The primary circuit cools the components known from the old compression refrigerator, ie the compressor, the first gas cooler for transferring heat from the refrigerant to the environment, the throttle member and the air supplied to the passenger compartment Including the evaporator. The secondary passage has two parts, the first part originates from a branch point located between the compressor and the first gas cooler, and is connected between the first gas cooler and the compressor. It extends to the entry point located between. The first part is provided with a second gas cooler for transferring heat from the cooler to the heated air in the passenger compartment, and a second throttle member that follows. The second part of the secondary passage originates from another branch point located between the second gas cooler and the compressor, and is located between the second gas cooler and the compressor. Extends to another entry point. In heat pump operation, the refrigerant passes through the second part of the secondary passage as well as the primary circuit of the HVAC system. First, in order to warm the air supplied to the passenger compartment, the refrigerant is compressed in the compressor, and then with the aid of an active switch valve, passes through the first part of the secondary passage that passes to the second gas cooler. . In the second gas cooler opposite the first gas cooler, heat is not dissipated to the environment and is used to heat the passenger compartment air. In the second throttle member, following the second gas cooler, the refrigerant is expanded from the compression pressure level to the average pressure level, typically to develop two-phase mixing. The refrigerant side temperature level in the evaporator is controlled by the average pressure level. On the one hand, the temperature level in the evaporator must not be reduced below 0 degrees in order to prevent the evaporator from freezing when the temperature in front of the evaporator exceeds 0 degrees. On the other hand, the temperature level in the evaporator should not exceed 0 degrees to avoid sudden fogging of the glazing when the air temperature is below 0 degrees in front of the evaporator. A part of the refrigerant is evaporated in the evaporator, whereby the air supplied to the passenger compartment is cooled and dehumidified. At the time of dehumidification, water contained as air humidity in the supplied air is condensed in the evaporator. Air dehumidified condensate must be removed from the HVAC system at all temperature conditions, particularly below 0 degrees. However, this may freeze the water in the condensate drain channel provided to remove the condensate and prevent the condensate outflow.

  The possibility of deicing the condensate drain hose is known from US Pat. In general, the HVAC system is provided with a drain hose attached to the vehicle body and having a terminal portion connected to the cooling device, whereas the other terminal portion has the water condensed from the cooling device flowing out. It is described that it is open as possible. Specifically, it is described that the drainage hose structure of the cooling device is provided with a drainage hose and a heating element disposed on the inner wall of the hose. The drainage hose can be heated by this additional heating element from the inside when the condensed water reaches the freezing temperature. The disadvantage of this drainage hose structure is that the hose diameter is narrowed and the internal volume of the hose is reduced due to the heating device. Furthermore, the heating device includes only a portion of the inner wall of the hose so that the inner wall of the hose is not heated uniformly.

German Patent Application Publication No. 10163607 German Patent Application No. 102006026359 JP-A-8-40052

  An air dehumidifier for the air supplied to the passenger compartment that ensures sufficient dehumidification of the supplied air at all temperature conditions and in all ventilation modes, combined with a cooling system and heat pump It is an object of the present invention to provide an automotive HVAC system established against. Specifically, the air dehumidifier is suitable for an automotive HVAC system that can heat the air for the passenger compartment even in a highly recirculated air portion without frosting the window glass at temperatures below -10 degrees in heat pump operation. .

  The object of the present invention is solved by an air dehumidifier of an automotive HVAC system for the combined operation of a cooling system and a heat pump, the automotive HVAC system comprising: a heat pump system having a heat exchanger that heats based on refrigerant; An evaporator for supplying heat from the air adjusted for the refrigerant that has passed through the circuit, the air dehumidifier to the air flow channel through which the air conditioned through the evaporator passes; In order to remove the water condensed in the evaporator from the conditioned air, the vertically directed condensed water drainage channel that branches off at the bottom of the airflow channel and the internal volume of the condensed water drainage channel from the outside Built into the condensate drain channel wall or placed outside the condensate drain channel so that it can be heated. Having a heating device that is.

  In one embodiment of the present invention, the heating device is installed as a heating wire built into the wall of the condensate drain channel and with a positive temperature coefficient (PTC).

  In particular, the heating device is in the form of an electrical resistance that is heated by a heating resistor incorporated in the channel wall of the condensate drainage channel. Preferably, a heating resistor having a positive temperature coefficient (PTC) is used.

  Advantageously, the heating device is in the form of an electrical fiber element with a positive temperature coefficient (PTC) incorporated in the wall of the condensate drain channel. Here, the condensate drainage channel is preferably a hose made of a plastic material with an electrical fiber element woven into the hose or incorporated into the hose by casting.

  According to a preferred embodiment of the present invention, the heating device is coupled to a control device or regulation device that allows the operation of the heating device depending on the ambient temperature via a constant heating mode or a mode controlled by an external signal. .

  A variation of the embodiment of the present invention is that the high pressure heat pump line of the heat pump system is placed in close proximity to the condensate drainage channel of the automotive HVAC system so that the high pressure heat pump line serves as a heating device.

  Another embodiment of the present invention is a process for dehumidifying conditioned air inside a vehicle in an automobile HVAC system that operates as a heat pump using an air dehumidifier according to the above-described embodiment. Passes through the evaporator along the air flow channel, the air regulated thereby is cooled, the water contained as air humidity is condensed in the evaporator, drained into the condensate drain channel, and the ambient temperature is Below 0 degrees, the electrical heating device is preferably operated in a constant heating mode or a mode controlled by an external signal.

  The heating device can be interrupted and activated. In one example of a process embodiment according to the present invention, the condensate drainage channel is heated directly by a heating device. With the heating device, the already frozen condensation melts. An essential advantage of the air dehumidifier according to the invention is that it is heated directly through the condensate drainage channel using a heating device around the condensate drainage channel. The frozen condensation is melted at the drainage channel walls and therefore from the outside.

  As a variant, the heating device is used indirectly. Indirect use of the heating device fulfills the task of maintaining a condensation temperature above 0 degrees. When using the heating device indirectly, the power consumption is kept low. Freezing does not occur in the condensate drain pipe.

  Preferably, the heating device is operated by ambient temperature via a constant heating mode or via a mode controlled by an external signal.

  The external signal advantageously depends on the value at which the ambient temperature is measured and / or the position of the recirculated air damper door and / or the humidity measurement.

  Further details, features and advantages of the invention will become apparent from the following details of exemplary embodiments in connection with the accompanying drawings.

It is sectional drawing of the motor vehicle HVAC system of the vicinity of an evaporator.

  FIG. 1 shows a cross-sectional view of an automobile HVAC system having an air dehumidifier 1 in the vicinity of an evaporator 2. The evaporator 2 serves to supply heat from the regulated air 3.1 inside the vehicle to the refrigerant of the heat pump system. The evaporator 2 is arranged in the air flow channel 4 so that incoming outside air 3.1 or recirculating air 3.1 must pass through the evaporator 2. The conditioned air 3.1 passes through the evaporator 2 at a temperature of, for example, 15 degrees and a relative air humidity of 80%, and after passing through the evaporator 2, the dehumidified air has a relative air humidity of, for example, 97% and a temperature of 3 degrees. Have In the vicinity of the air flow channel 4 downstream of the evaporator 2, the condensate drain channel 5 directed in the vertical direction is placed at a position where the liquid condensate 6.1 can flow downward. A condensate drain channel 5 (drainage) is provided for drainage of the HVAC system. As shown in FIG. 1, the condensate drainage channel 5 (switched downward in the direction of the air 3 flow) is located behind the evaporator 2 and is directed perpendicular to the airflow channel 4 and thus , Directed in the direction of the flow of the supplied air 3. The guide element 7 extends from the front edge on the bottom side of the evaporator 2 to the inlet of the condensed water drainage channel 5, forms a slope, and the water 6.1 condensed in the evaporator 2 is supplied to the condensed water drainage channel 5. Ensure that it can incline and flow out.

  At ambient temperatures above 0 degrees, a portion 6.2 of the condensed water transferred from the drying process can be frozen.

  The air dehumidifier 1 is incorporated into the channel wall 9 of the condensate drain channel 5 or arranged outside the condensate drain channel 5 close to the condensate drain channel 5 as shown in FIG. The heating device 8 is provided. Therefore, the heating device 8 can heat the internal volume 10 of the condensed water drainage channel 5 from the outside.

  The heating device 8 shown in FIG. 1 can be in the form of a heating wire 8 incorporated in the channel wall 9 of the condensate drain channel 5 and having a positive temperature coefficient (PTC). Alternatively, the heating device 8 may be in the form of electrical resistance heating 8 incorporated in the channel wall 9 with one or several heating resistors. The heating device 8 may also be in the form of an electrical fiber element 8 incorporated in the channel wall 9 of the condensate drain channel 5 and having a positive temperature coefficient (PTC). Preferably, the condensate drain channel 5 is a hose 5 made of a plastic material with an electrical fiber element 8 woven into the hose or incorporated into the hose by casting.

DESCRIPTION OF SYMBOLS 1 Dehumidifier 2 Evaporator 3 Air 3.1 Conditioned air, inflowing external air / recirculating air 3.2 Dehumidified air 4 Air flow channel 5 Condensate drain channel, hose 6.1 Condensed water 6.2 Already Part of frozen condensed water 7 Guide element 8 Heating device, electric fiber element, heating wire, resistance heating 9 Channel wall 10 Internal volume of condensate drainage channel

Claims (2)

An air dehumidifying device (1) of an automobile HVAC system for an operation combining a cooling system and a heat pump, wherein the automobile HVAC system includes a heat pump system including a heat exchanger that heats based on a refrigerant, and the interior of the automobile And an evaporator (2) for supplying heat to the refrigerant that has passed through the circuit from the air (3.1) adjusted for the air dehumidification device (1),
An air flow channel (4) in which the evaporator (2) is arranged to guide the air (3.1) conditioned through the evaporator (2);
In order to remove the water (6.1) condensed in the evaporator (2) from the conditioned air (3.1), it branches off at the bottom side of the air flow channel (4) and is directed vertically. Condensate drainage channel (5) formed,
It is incorporated into the channel wall (9) of the condensate drain channel (5) or the condensate drain channel (5) so that the internal volume (10) of the condensate drain channel (5) can be heated from the outside. and proximity to the condensed water drain channel (externally arranged heating devices 5) (8)), have a,
The heating device (8) is in the form of the high pressure heat pump line of the heat pump system such that a high pressure heat pump line is attached along the condensed water drainage channel (5) in the vicinity of the condensed water drainage channel (5). An air dehumidifier (1) characterized in that it exists . The heating device (8) is coupled to a control or regulation device capable of operating the heating device (8) depending on the ambient temperature via a constant heating mode or a mode controlled by an external signal. air dehumidifier according to claim 1, wherein that (1).