A FAN ARRANGEMENT IN A VEHICLE

Abstract

A fan arrangement for a cooling module in a vehicle. The vehicle (6) has a radiator fan (10) providing an air flow through a flow passage (5) and the cooling module in an intended flow direction. The cooling module includes a radiator (3) and at least one further cooler (1, 2) arranged in an upstream position of the radiator (3) with respect to the intended flow direction through the flow passage (5). The fan arrangement includes at least one additional electrically driven fan (4). The additional electrically driven fan (4) is arranged in the flow passage (5) in a position downstream of the radiator (3) and upstream of the radiator fan (10) with respect to the intended flow direction through the flow passage (5). The electrically driven fan (4) is configured to provide an air flow through a restricted portion (18) of the flow passage (5) and the cooling module during certain occasions when the operating conditions include the radiator fan not being in operation.

Claims

1. A fan arrangement for a cooling module arranged in an air flow passage in a vehicle, wherein the vehicle comprises a radiator fan configured and operable to be driven by a combustion engine and the radiator fan being configured and operable to provide an air flow in an intended direction through the air flow passage and the cooling module; the cooling module comprises a radiator of a cooling system configured and operable for cooling the combustion engine, and at least one further cooler arranged in an position upstream of the radiator with respect to the intended flow direction through the flow passage; an additional electrically driven fan arranged in the flow passage in a position downstream of the radiator and upstream of the radiator fan with respect to the intended flow direction through the flow passage; the flow passage having a restricted portion; and the electrically driven fan is configured to provide an air flow through the restricted portion of the flow passage and through the cooling module during occasions when the radiator fan is not in operation; the electrically driven fan is configured and operable to also provide an air flow through the restricted portion of the flow passage in an opposite direction to the intended flow direction through the flow passage; the further cooler is a charge air cooler configured and operable for cooling charge air delivered to the combustion engine; and the electrically driven fan is configured and operable to provide an air flow through the restricted portion of the flow passage and through the charge air cooler in the direction opposite to the intended flow direction through the flow passage.

2. A fan arrangement according to claim 1, wherein the additional electrically driven fan is arranged in the flow passage in a position closer to the radiator than to the radiator fan.

3. A fan arrangement according to claim 1, further comprising: a fan cover of the radiator fan defining a part of the flow passage; and the electrically driven fan is arranged in the part of the flow passage defined by the fan cover of the radiator fan.

4. A fan arrangement according to claim 1, further comprising: at least one component configured to provide an air channel defining the restricted portion of the flow passage.

5. A fan arrangement according to claim 1, further comprising an annular element arranged in a space between the further cooler and the radiator; and the air channel within the flow passage is defined by the annular element.

6. A fan arrangement according to claim 1, wherein the cooling module comprises at least two further coolers.

7. A fan arrangement according to claim 4, wherein the air channel within the flow passage is defined by an annular element arranged in a space between the two coolers.

8. A fan arrangement according to claim 4, further comprising the fan cover of the electrically driven fan is configured to define the air channel within the flow passage.

9. A fan arrangement according to claim 1, further comprising the further cooler comprises a condenser of an AC system, and the electrically driven fan is configured to provide an air flow through the restricted portion of the flow passage and the condenser of the AC system.

10. A fan arrangement according to claim 1, wherein the electrically driven fan is reversible in its direction of rotation.

11. A fan arrangement according to claim 1, wherein the electrically driven fan is operable to provide an air flow through the restricted portion of the intended flow through the flow passage in the direction opposite to the intended flow direction during occasion when there is risk for ice formation in the charge air cooler.

12. A fan arrangement according to claim 9, wherein the driven fan is configured to provide an air flow through the restricted portion of the flow passage and the condenser of the AC system during occasions when the AC system is in operation and the combustion engine is not running.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0015] In the following a preferred embodiment of the invention is described, as an example, with reference to the attached drawings, in which:

[0016] FIG. 1 shows a front view of a cooling module in a vehicle comprising a fan arrangement according the invention and

[0017] FIG. 2 shows a schematic cross-sectional view of the cooling module in the plane A-A in FIG. 1.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

[0018] FIG. 1 shows a front view of a cooling module. The cooling module comprises a condenser 1 of an AC system in a front position. The condenser 1 receives a gaseous refrigerant via an inlet line 1a. The refrigerant is cooled in the condenser 1 by a cooling air flow to a temperature at which it condenses. The liquefied refrigerant leaves the condenser 1 via an outlet line 1b. A charge air cooler 2 is arranged in a position behind, that is normally located downstream of, the condenser 1. The charge air cooler 2 comprises an inlet tank 2a, a cooling portion 2b and an outlet tank 2c. Charged air is delivered to the inlet tank 2a via an inlet conduit 2a.sub.1. The charged air is cooled in the cooling portion 2b by a cooling air flow. The cooled charged air is received in the outlet tank 2c before it leaves the charge air cooler 2 via an outlet conduit 2c.sub.1. A radiator 3 is arranged in a position behind the charge air cooler 2. The radiator 3 comprises an inlet tank 3a, a cooling portion 3b and an outlet tank 3c. Coolant is received in the inlet tank 3a. The coolant is delivered to the cooling portion 3b where it is cooled by a cooling air flow. The cooled coolant is received in the outlet tube 1c before it leaves the radiator 3. Two additional fans 4 are indicated with dotted lines. The additional fans 4 are arranged behind the radiator 3. The additional fans 4 are operated by means of a respective electric engine 4a. The fans 4 and the electric engine 4a are mounted as a unit in a position close to the radiator 3. The fans 4 and the electrical engines 4a may be mounted by means of suitable mounting profiles attached to the inlet tank 3a and the outlet tank 3c of the radiator 3.

[0019] FIG. 2 shows a cross-sectional view in the plane A-A in FIG. 1. The condenser 1, the charge air cooler 2 and the radiator 3 is arranged in a flow passage 5 in a vehicle 6 which may be a heavy vehicle. The flow passage 5 comprises an opening 5a arranged in a front portion of the vehicle 5. A front wall 7 of the vehicle and a bumper 8 defines the opening 5a of the flow passage 5. A grille 9 is arranged in the opening 5a. The grille 9 is, in this case, defined by a number of vertical bars having a parallel extension across the opening 5a of the air passage 5. A radiator fan 10 is configured to provide a cooling air flow through the cooling module in the flow passage 5. The radiator fan 10 is driven by a combustion engine 11 via a clutch 12. A control unit 13 controls the engagement and the disengagement of the clutch 12.

[0020] The combustion engine 11 is arranged in an engine room or compartment 14 of the vehicle 6. The control unit 13 receives substantially continuously information from a temperature sensor 15 about the temperature of coolant which is cooled in the radiator 3 and which cools the combustion engine 11. The control unit 13 starts the radiator fan 10 when the coolant has a temperature above a predetermined temperature. During operation, the radiator fan 10 provides an air flow in an intended flow direction through the flow passage 5. The air flow is comprised of ambient air which it directed into the flow passage 5, via the inlet opening 5a. In the flow passage 5, the air flows through the condenser 1, the charge air cooler 2 and the radiator 3. The air flow cools the refrigerant in the condenser 1, the charge air in the charge air cooler 2 and the coolant in the radiator 3.

[0021] The condenser 1 is arranged in the flow passage 5 in a position relatively close to the inlet opening 5a and the grille 9. The charge air cooler 2 is arranged at a distance behind the condenser 1. A first annular element 16 is arranged in the space between the condenser 1 and the charge air cooler 2. The first annular element 16 is attached on the condenser 1 and/or the charge air cooler 2. The radiator 3 is arranged at a distance behind the charge air cooler 2. A second annular element 17 is arranged in the space between the charge air cooler 2 and the radiator 3. The second annular element 17 is attached on the charge air cooler 2 and/or the radiator. The first annular element 16 and the second annular element 17 forms together with air flow passages through the condenser 1, air flow passages through the charge air cooler 2, air flow passages through the radiator 3 and a fan cover 4b of the additional fan 4 an air channel 18 in a restricted portion of the flow passage 5. Each additional fan 4 is configured to provide an air flow through such an air channel 18. The control unit 13 controls the activation of the electric engine 4a and the speed of the additional fan 4. The speed of the additional electrically driven fans may be regulated in a stepless manner. The additional fans 4 are reversible in their respective direction of rotation. Thus, it is possible to provide an air flow through the air channel 18 in the intended flow direction through the flow passage 5 and in an opposite direction to the intended flow direction through the flow passage 5.

[0022] The use of the additional fans 4 has several applications. When a driver wishes to take a break on a warm day, it is possible to start the AC system when the combustion engine is not in operation. In this case, the driver can indicate start of the AC system by means of a button 19 or the like. When this is indicated, the control unit 13 initiates supply of electrical energy from a battery or the like in the vehicle 6 to a compressor of the AC system and to the electrical engines 4a powering the additional electrically driven fans 4. The additional fans 4 start and they provide an air flow through the respective air channel 18 in the intended flow direction through the air passage 5. Ambient air is sucked into the flow passages 5, via the opening 5a, and through the air channels 18. The air flow through the air channels 18 provides a required cooling of the refrigerant in the condenser 1. The annular elements 16, 17 and the fan cover 4b of the additional fans 4, define a substantially tight air channel 18. By means of such air channels 18, it is possible to provide concentrated air flows through relevant parts of the condenser 1. Substantially the whole air flow provided by the respective additional fans 4 is directed through the condenser 1. As a consequence, it is possible to use additional electrically driven fans 4 with a relatively small capacity. It is usually an empty space in the flow passage 5 in a position between the radiator 3 and the radiator fan 10 which is defined by the radiator fan cover 10a. The additional fans 4 and the electrical engines 4a are arranged in this space. Consequently, the additional fans 4 are arranged in a downstream position of the radiator 3 and in an upstream position of the radiator fan 10 with respect to the intended flow direction through the flow passage 5.

[0023] Another application of the additional fans 4, is when the combustion engine is operated and ambient air has a very low temperature. During such occasions, the radiator fan is usually not driven. Since the combustion engine is operated, charge air is directed to the charge air cooler 2. During such occasions, the water vapor in the charge air may be liquefied and frozen in the charge air cooler 2. If that occurs, the supply of charge air to the combustion engine 11 will be reduced and possibly ceased. In order to avoid this risk, the control unit 13 may receive information from a temperature sensor 20 about ambient temperature or the temperature of the charge air leaving the charge air cooler 2. In case the received temperature indicates such a risk, the control unit 13 activates the additional fans 4 such that they provide an air flow in the flow channels 18 in an opposite direction to the above described intended flow direction through the flow passage 5. As a consequence, the additional fan 4 provides an air flow from the engine room 14 and through the air channels 18. The air flows in the air channels 18 are directed through the radiator 3, the charged air cooler 2 and the condenser 1. The air inside the engine room 14 usually has a considerably higher temperature than ambient air since it is in contact with the combustion engine 11. Consequently, relatively hot air flows from the engine room 14 and through the charge air cooler 2 where it melts possible ice formations.

[0024] Finally, it is possible to use the additional fans 4 instead of the radiator fan 10 for cooling of the refrigerant in the condenser 1 during certain operating conditions, such as city driving. In city traffic, the ram air flow through the condenser 1 is many times too low for cooling the refrigerant. In this case, it is possible to start the additional fans 4 instead of the radiator fan 10 for cooling the refrigerant in the condenser 1. In case the additional fans 4 are dimensioned for this purpose, it is usually more energy efficient to start them than to start the considerably larger radiator fan 10.

[0025] The invention is not restricted to the described embodiment but may be varied freely within the scope of the claims. The cooling module may, for example, comprise a variable number of coolers.