阅读说明：本技术 用于作业车辆中的hvac系统的新鲜空气过滤器再生 (Fresh air filter regeneration for HVAC systems in work vehicles ) 是由 D·费里 J·奎特尔科罗米纳斯 于 2018-05-10 设计创作，主要内容包括：一种用于与作业车辆(12)的驾驶室(10)一起使用的HVAC系统(14)的特征在于与第一风扇(28)的出口和第二风扇(30)的出口连通的空气管道装置(18)。至少一个空气流转向器(66)被定位于所述空气管道装置(18)内,用于选择性地使流动通过所述空气管道装置(18)的空气转向。在“新鲜空气过滤器再生”模式期间,所述至少一个空气流转向器(66)关闭所述空气管道装置(18),所述第一风扇(28)被启动,并且所述第二风扇(30)被停用,由此来自所述第一风扇(28)的排出空气沿反向方向流动通过所述第二风扇(30)并且流动通过所述新鲜空气过滤器(50)。(An HVAC system (14) for use with a cab (10) of a work vehicle (12) is characterized by an air duct arrangement (18) in communication with an outlet of a first fan (28) and an outlet of a second fan (30). At least one air flow diverter (66) is positioned within the air duct arrangement (18) for selectively diverting air flowing through the air duct arrangement (18). During a "fresh air filter regeneration" mode, the at least one airflow diverter (66) closes the air duct arrangement (18), the first fan (28) is activated, and the second fan (30) is deactivated, whereby exhaust air from the first fan (28) flows in a reverse direction through the second fan (30) and through the fresh air filter (50).)

1. A heating, ventilation, and air conditioning (HVAC) system (14) for a cab (10) of a work vehicle (12), the HVAC system (14) comprising:

a first fan (28) having an inlet (34) and an outlet, the inlet (34) of the first fan communicating with an interior (36) of the cab (10);

a second fan (30) having an inlet (38) and an outlet, the inlet (38) of the second fan being in communication with an external ambient environment (40);

a fresh air filter (50) positioned in communication with the inlet (38) of the second fan (30);

the method is characterized in that:

the HVAC system (14) further comprises:

air duct means (18) communicating with the outlet of the first fan and the outlet of the second fan; and

at least one air flow diverter (66) positioned within the air duct arrangement (18) for selectively diverting air flowing through the air duct arrangement (18); and

wherein in a "fresh air filter regeneration" mode, the at least one airflow diverter (66) closes the air duct arrangement (18), the first fan (28) is activated, and the second fan (30) is deactivated, whereby exhaust air from the first fan (28) flows in a reverse direction through the second fan (30) and through the fresh air filter (50).

2. The HVAC system (14) of claim 1, wherein the HVAC system (14) includes an HVAC module (16) having a recirculation tank (54) coupled with the inlet (38) of the second fan (30), the recirculation tank (54) controlling an amount of recirculation air and fresh air drawn into the second fan (30), the recirculation tank (54) having a controllable first door (56) in communication with the interior (36) of the cab (10), and a controllable second door (58) in communication with an external ambient environment (40), the first door (56) being closed and the second door (58) being open during the fresh air filter regeneration mode.

3. The HVAC system (14) of claim 1, wherein:

the air duct arrangement (18) including at least one distribution plenum (62), each distribution plenum (62) having at least one outlet (64) and an inlet in communication with the outlet of the first fan and the outlet of the second fan, each distribution plenum (62) including at least one of the airflow diverters (66); and

electrical processing circuitry (74) is configured in the fresh air filter regeneration mode to position the at least one airflow diverter (66) to close each outlet of each of the distribution plenums (62).

4. The HVAC system (14) of claim 1, wherein:

the fresh air filter regeneration mode requires that an output signal received from a door sensor (76B) of the cab (10) indicates that an access door (52B) is open.

5. The HVAC system (14) of claim 1, wherein an electrical processing circuit (74) coupled with the first fan (28) and the second fan (30) initiates the fresh air filter regeneration mode on a time basis.

6. The HVAC system (14) of claim 4, wherein the electrical processing circuit (74) coupled with the first fan (28) and the second fan (30) initiates the fresh air filter regeneration mode when the output signal received from a second door sensor of the cab (10) indicates that the second door is closed.

7. The HVAC system (14) of claim 5, wherein the time base corresponds to a predetermined number of hours of operation of the work vehicle (12).

8. The HVAC system (14) of claim 3, wherein the air duct arrangement (18) includes a forward ducting arrangement (24) having at least one of the air flow diverters (66A, 66B) and a parallel ducting arrangement (26) having at least one of the air flow diverters (72), the electrical processing circuit (74) controlling each of the air flow diverters (66A, 66B, 72) to turn off each of the forward and aft ducting arrangements (24, 26) during the fresh air filter regeneration mode.

9. The HVAC system (14) of claim 8, wherein:

the HVAC system (14) includes an HVAC module (16) including each of the first fan (28) and the second fan (30); and

the forward delivery arrangement (24) includes a distribution plenum (62) having a plurality of outlets (64) and inlets in communication with the outlets of the first and second fans, the distribution plenum (62) including at least one of the airflow redirectors (66A, 66B) for selectively opening and closing the plurality of outlets (64).

10. The HVAC system (14) of claim 1, wherein the fresh air filter regeneration mode is initiated in accordance with at least one sensed or calculated operating parameter associated with the fresh air filter (50).

11. The HVAC system (14) of claim 10, wherein the at least one sensed or calculated operating parameter comprises a pressure drop across the fresh air filter (50).

12. The HVAC system (14) of claim 1, wherein the first fan (28) is a recirculation blower and the second fan (30) is a booster blower.

13. A work vehicle comprising an HVAC system (14) as set forth in any one of the preceding claims.

Technical Field

The present invention relates generally to a climate control system for the interior of a cab of a self-propelled work vehicle such as a tractor, agricultural harvester, or the like, and more particularly to a climate control system configured for regeneration of a fresh air filter.

Background

Work vehicles are used in the agricultural, industrial, mining, construction, and forestry arts to perform various work functions, such as farming, planting, harvesting, combine harvesting, and the like. In order to improve operator comfort, such work vehicles are often provided with a cab in which the operator is located. The cab typically comprises a metal frame with uprights, a roof and transparent glass or plastic panels extending between the uprights. The operator may operate various levers, switches, etc. from within the cab to perform various desired functions, such as engaging or disengaging a power take-off, activating a remote hydraulic cylinder, selecting a throttle speed, etc.

Climate control systems, also commonly referred to as Heating Ventilation and Air Conditioning (HVAC) systems, are commonly used to control or regulate environmental conditions such as temperature, humidity, and/or air pressure within an enclosed cabin. The HVAC system of a work vehicle typically includes a plurality of operator-operable controls located within the cab, including, but not limited to, a mode selector, a temperature selector, and a fan speed selector. The mode selector will typically allow selection of a heating mode, an air conditioning mode, a window defrost demist mode, an air recirculation mode, and a fresh air mode. Additionally, some systems may operate in an Automatic Temperature Control (ATC) mode, where the system controls the cabin air temperature to an operator selectable value or range of operator selectable values. Still further, some systems may operate in a mode that automatically controls fan speed and other elements of the system to maintain cabin air pressure at a level above the pressure of the outside air to limit infiltration of outside air, dust, and other contaminants from the outside environment into the cabin.

U.S. patent No. 8,633,424, assigned to the assignee of the present invention, discloses an HVAC system with two centrifugal blowers. One blower is used to pressurize the operating room with outside air, and the other blower is used to recirculate air within the operating room. The two blowers are fluidly connected in series with each other such that the outlet of the booster blower is in communication with the inlet of the recirculation blower.

It is also known to automatically clean filters in the duct between the external ambient environment and the HVAC blower. EP2552719B1 (corresponding to U.S. patent publication No. US 2013/0059521) discloses an HVAC system with a single blower. A mixing flap is positioned on an upstream side of the blower to allow selective intake of recirculation air from the cabin interior and/or exterior air through a filter. A plurality of air distribution vents are located on a downstream side of the blower to direct pressurized air to selected areas within the cab. In the "filter regeneration" mode, the downstream side air distribution vent is closed and the mixing flap is positioned to draw in only recirculated air and close the inlet to the filter. A return duct leading from an outlet side of the blower back to the filter returns the pressurized air to the filter to blow air through the filter in a reverse direction and thereby regenerate the filter.

Disclosure of Invention

The present invention provides an HVAC system for a work vehicle including a pair of blowers, wherein a downstream ducting arrangement may be turned off and air from a recirculation blower is used to blow air through a booster blower and a fresh air filter to clean and regenerate the fresh air filter.

The invention in one form relates to an HVAC system for a cab of a work vehicle. The HVAC system includes a first fan having an inlet and an outlet, wherein the first fan inlet communicates with an interior of the cab. A second fan has an inlet and an outlet, wherein the second fan inlet is in communication with the external ambient environment. A fresh air filter is positioned in communication with the inlet of the second fan. The HVAC system is characterized by an air duct arrangement in communication with the first fan outlet and the second fan outlet. At least one air flow diverter is positioned within the air duct arrangement to selectively divert air flowing through the air duct arrangement. During a "fresh air filter regeneration" mode, the at least one air flow diverter shuts off the air ducting, the first fan is activated, and the second fan is deactivated, whereby exhaust air from the first fan flows in a reverse direction through the second fan and through the fresh air filter.

In another embodiment, the HVAC module includes a recirculation tank coupled with an inlet of the second fan. The recirculation tank controls the amount of recirculation air and fresh air drawn into the second fan. The recirculation tank has a controllable first door in communication with the interior of the cab and a controllable second door in communication with the external ambient environment. During the fresh air filter regeneration mode, the first door is closed and the second door is opened.

In another embodiment, the air duct arrangement includes at least one distribution plenum, wherein each distribution plenum has at least one outlet and an inlet in communication with the first fan outlet and the second fan outlet. Each of the distributed plenums contains at least one airflow redirector. The electrical processing circuitry is configured to position the at least one airflow diverter to close the outlet(s) of each of the distributed plenums in a fresh air filter regeneration mode.

In another embodiment, the cab includes a first access door and a second access door, and the HVAC system further includes a first door sensor associated with the first access door, and a second door sensor associated with the second access door. The first and second door sensors are each coupled with the electrical processing circuit and provide an output signal to the electrical processing circuit. The fresh air filter is positioned at a top of the cab proximate the second access door. The electrical processing circuit initiates the fresh air filter regeneration mode when the output signal from the first door sensor indicates that the first door is opened and when the output signal from the second door sensor indicates that the second door is closed.

In another embodiment, the electrical processing circuit initiates the fresh air filter regeneration mode on a time basis. The time base may correspond to a predetermined number of hours of operation of the work vehicle.

In yet another embodiment, the air duct arrangement includes a forward delivery arrangement having at least one air flow diverter and an aft delivery arrangement having at least one air flow diverter. The electrical processing circuit controls each airflow diverter to close the forward and aft delivery arrangements during a fresh air filter regeneration mode.

In yet another embodiment, the HVAC system includes an HVAC module containing the first fan and the second fan. The forward transport arrangement includes a distribution plenum having a plurality of outlets and an inlet in communication with the first fan outlet and the second fan outlet. The distribution plenum includes at least one airflow diverter for selectively opening and closing the plurality of outlets.

In another embodiment, the HVAC module includes a recirculation tank coupled with an inlet of the second fan. The recirculation tank controls the amount of recirculation air and fresh air drawn into the second fan. The recirculation tank has a controllable first door coupled with the electrical processing circuit and in communication with the interior of the cab, and a controllable second door coupled with the electrical processing circuit and in communication with the external ambient environment. During the fresh air filter regeneration mode, the first door is closed and the second door is opened.

In yet another embodiment, the first fan is a recirculation blower and the second fan is a booster blower.

In another embodiment, the work vehicle is an agricultural tractor.

Drawings

The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a perspective view of a portion of a cab that may be used on a work vehicle, including an embodiment of the HVAC system of the present invention;

FIG. 2 is a perspective view of an HVAC system for use in the cab shown in FIG. 1;

FIG. 3 is a perspective view of an HVAC module for use in the HVAC system shown in FIG. 2;

FIG. 4 is a perspective view of a portion of a fresh air arrangement for use with the HVAC system shown in FIG. 2;

FIG. 5 is a perspective view of a recirculation tank used with the HVAC system shown in FIG. 2 and the fresh air arrangement shown in FIG. 4;

FIG. 6 is a side cut-away view showing the interior of an air distribution plenum used in the front feed arrangement of the HVAC system shown in FIG. 2 with two different types of airflow redirectors within the air distribution plenum;

FIG. 7 is a perspective view of the air distribution plenum shown in FIG. 6 with the airflow redirector in a different position; and

FIG. 8 is a schematic view of another embodiment of the HVAC system of the present invention.

Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.

Detailed Description

Referring now to the drawings, and more particularly to fig. 1 and 2, there is shown a portion of a cab 10 that may be used on a work vehicle 12. In the illustrated embodiment, it is assumed that work vehicle 12 is an agricultural tractor, but work vehicle 12 may be a different type of work vehicle, such as a combine, a cutter-rower, a backhoe, a dozer, an excavator, a feller-stacker, and so forth. The cab 10 is intended to improve operator comfort.

The HVAC system 14 shown in perspective view in fig. 2 is primarily intended to provide heated, cooled, and filtered air to the interior of the cab 10. The HVAC system 14 generally includes an HVAC module 16 and an air duct arrangement 18. The air duct arrangement 18 may further be considered to be subdivided on the intake side into a recirculation arrangement 20 and a fresh air arrangement 22, and on the discharge side into a front conveying arrangement 24 and another parallel conveying arrangement 26, for example a rear conveying arrangement 26 or a side conveying arrangement.

The HVAC module 16 (fig. 2 and 3) may be positioned below the floor in the cab 10 and contain a first fan 28 and a second fan 30 within a common housing 32. The first fan 28 has an inlet 34 and an outlet (within the housing 32, not numbered), wherein the first fan inlet 34 communicates with an interior 36 (fig. 1) of the cab 10. The second fan 30 has an inlet 38 and an outlet (within the housing 32, not numbered), wherein the second fan inlet 38 is in communication with an external ambient environment 40 (fig. 1). In the illustrated embodiment, the first fan 28 and the second fan 30 are each configured as centrifugal blowers. However, it should be understood that the fans 28 and 30 may be configured as different types of fans, such as axial flow fans.

The recirculation arrangement 20 on the intake side of the first fan 28 comprises an inlet with a recirculation air filter 42, through which recirculation air from the interior 36 is drawn into a recirculation air duct 44. Discharge end of recirculation air duct 44 and

the inlet of the first fan 28 is connected as shown in fig. 2.

The fresh air arrangement 22 (fig. 2 and 4) on the intake side of the second fan 30 receives both recirculated air from the interior 36 of the cab 10 and fresh air from the external ambient environment 40. To this end, the fresh air arrangement 22 comprises an inlet with a second recirculation air filter 46, through which second recirculation air filter 46 recirculation air from the interior 36 is drawn into the inlet 38 of the second fan 30. The fresh air arrangement 22 also comprises a fresh air duct 48 which is interconnected between the inlet 38 of the second fan 30 and the external ambient environment 40. In the illustrated embodiment, the substantially horizontal portion 48A of the fresh air duct 48 is a portion of the hollow frame of the cab 10 below the rear window, and the substantially vertical portion 48B of the fresh air duct 48 is a portion of the hollow frame right rear pillar of the cab 10. A fresh air filter 50 is positioned at the inlet of fresh air duct 48 extending to inlet 38 of second fan 30 above right access door 52A of cab 10.

To control the mixture of recirculated air and fresh air to the second fan 30, the HVAC module 16 includes a recirculation tank 54 (fig. 2, 4, and 5) coupled with the inlet 38 of the second fan 30. The recirculation tank 54 has a controllable first door 56 which communicates with the interior of the cab 10 via the second recirculation air filter 46, and a controllable second door 58 which communicates with the external surroundings 40 via the fresh air duct 48 and the fresh air filter 50. The positions of the first door 56 and the second door 58 may be independently and variably adjusted to control the mixture of recirculated air and/or fresh air entering the inlet 38 of the second fan 30, as will be described in greater detail below.

The housing 32 of the HVAC module 16 internally combines the outlet flows of the first and second fans 28, 30 together. As can be seen in fig. 2, the front conveying arrangement 24 is connected to outlets (not explicitly visible) located at the front, bottom of the HVAC module 16. The forward delivery arrangement 24 has a pair of parallel connected forward delivery ducts 60A and 60B, each connected in parallel with an air distribution plenum 62 (FIGS. 2, 6 and 7; which may also be referred to as a distributor box). The air distribution plenum 62 has a plurality of outlets 64 and at least one airflow diverter 66 for selectively opening and closing the plurality of outlets 64. Outlet 64 may act as a vent within cab 10 to direct air in a particular direction (e.g., defrost, upper vent, lower vent, foot, etc.). In the illustrated embodiment, the cross-section of the air flow diverter 66A has a generally quarter-circular shape, and the air flow diverter 66B is configured as a flap. The particular shape of the airflow redirector(s) 66 may vary depending on the application.

Referring again to fig. 2 and 3, the rear transport arrangement 26 is connected to an outlet 68 located at the front, top of the HVAC module 16. The rear delivery arrangement 26 has a pair of parallel connected rear delivery ducts 70A and 70B positioned to act as defrost vents on the rear window of the cab 10. A controllable air flow diverter 72 in the form of a rotatable flap is positioned at the outlet 68 and selectively controls the amount of air flowing through the rear delivery ducts 70A and 70B.

The electrical processing circuit 74 controls the various controllable components of the HVAC system 14. For example, the electrical processing circuitry 74 may be coupled with the first fan 28, the second fan 30, the first door 56, the second door 58, the airflow redirectors 66A and 66B, and the airflow redirector 72 via suitable connections (e.g., wired, wireless, BUS, etc.). The electrical processing circuitry 74 may also receive input from other suitable devices, such as a right door sensor 76A and a left door sensor 76B that indicate the open/closed status of the right access door 52A and the left access door 52B, respectively. The electrical processing circuit 74 may also be coupled to and/or contain other suitable electrical components, such as a video display 78, short-term and/or long-term memory (not shown), and so forth.

The electrical processing circuit 74 may be configured as a digital and/or analog circuit and may be part of another controller or a separate controller. For example, in the embodiment shown in fig. 1 and 2, the electrical processing circuit 74 is shown as part of a Vehicle Control Unit (VCU) that may be located in the armrest control panel 80. Alternatively, the electrical processing circuitry 74 may be a stand-alone controller that is an integral part of the HVAC module 16 that is coupled to the VCU via a suitable connection (such as a wired or wireless connection).

During operation, the electrical processing circuit 74 initiates and controls a "fresh air filter regeneration" mode in which the fresh air filter 50 is cleaned by blowing air in a reverse direction through the fresh air filter 50 to the ambient environment 40. This air expels the dust collected in the fresh air filter 50 to the ambient environment 40.

More specifically, the electrical processing circuit 74 initiates and controls the "fresh air filter regeneration" mode based on at least three boolean inputs (logical and operation). To this end, the electrical processing circuit initiates a fresh air filter regeneration mode on a time basis. In the illustrated embodiment, the time base may correspond to a predetermined number of hours of operation of work vehicle 12, and may be determined using an internal clock or timer (not specifically shown). For example, the fresh air filter regeneration mode may be initiated every 50 hours of operation of work vehicle 12.

Instead of being time dependent, the fresh air filter regeneration mode may also be initiated based on one or more sensed or calculated operating parameters associated with the fresh air filter 50. For example, when the second fan 30 is operating at a selected operating speed, the pressure drop across and across the fresh air filter 50 should fall within a known pressure range (Δ Ρ). A pressure sensor 84 on the inlet side of the fresh air filter 50 and a pressure sensor 86 on the exhaust side of the fresh air filter may be used, each of which is coupled to the electrical processing circuit 74. The output signals from pressure sensors 84 and 86 may be used to determine the pressure drop across fresh air filter 50. When the pressure drop exceeds a predetermined value, the operator may be provided with some type of indication to manually initiate the fresh air filter regeneration mode, such as text on a video display, indicator lights, alarms, and the like. If the fresh air filter 50 is not being regenerated and the performance is further degraded, another indication may be provided to the operator to manually initiate the fresh air filter regeneration mode, or the electrical processing circuitry 74 may automatically initiate the fresh air filter regeneration mode.

The electrical processing circuit 74 also initiates the fresh air filter regeneration mode based on the output signal from the right door sensor 76A indicating that the right door 52A is closed and the output signal from the left door sensor 76B indicating that the left door 52B is open. Since the fresh air filter is positioned above the right door 52A, this allows intake air used in filter regeneration to be drawn through the left door 52B that is open, and prevents dust exiting the fresh air filter 50 from entering the cab 10.

However, the fresh air filter 50 need not be positioned above one of the doors, but may instead be positioned at another suitable location, such as in a fender of the cab 10, below the floor of the cab 10, etc. In such a case, the electrical processing circuit 74 need not sense whether the right door is closed, but instead may sense only whether one of the access doors 52A or 52B is open to provide a source of fresh air during the fresh air filter regeneration mode. For example, one or both sensors 76A and/or 76B may be used to sense whether one or both of access doors 52A or 52B is open, independent of whether a particular door (such as access door 52A) is closed. Alternatively, another component may be sensed, such as an open window providing a source of air during a fresh air filter regeneration mode.

The electrical processing circuit 74 controls the airflow redirectors 66A, 66B and 72 to turn off the forward and aft delivery arrangements 24 and 26 during the fresh air filter regeneration mode. Fig. 6 shows air flow diverters 66A and 66B positioned to provide filtered and conditioned air to the upper vent, lower vent, and the foot. Fig. 7 shows the airflow redirectors 66A and 66B with the outlet 64 closed during the fresh air filter regeneration mode.

The electrical processing circuit 74 also controls the first door 56 and the second door 58 (as shown in fig. 5) such that the flow path for the recirculation air is closed and the flow path for the fresh air is opened. The electrical processing circuit then activates the first fan 28 and deactivates the second fan 30, whereby the exhaust air from the first fan 28 flows in a reverse direction through the second fan 30 and through the fresh air filter 50, thereby cleaning the fresh air filter 50 and regenerating the fresh air filter 50. The air flow path during the fresh air filter regeneration mode is schematically illustrated by flow path 82 shown in fig. 1.

Referring now to FIG. 8, a schematic diagram of another embodiment of an HVAC system 90 of the present invention is shown. In this embodiment, similar to the HVAC system 14 shown in fig. 1 and 2, the HVAC module 92 contains a recirculation fan 94 and a booster fan 96. However, the HVAC system 90 has a flow separation wall 98 positioned on a downstream side of the HVAC module 92 and an airflow diverter 100 positioned in alignment with the wall 98. The air flow diverter 100, which in the illustrated embodiment is configured as a butterfly valve, may be controllably positioned between an open position (shown in solid lines) and a closed position (shown in phantom lines) using the electrical processing circuitry 74. When in the fresh air filter regeneration mode, and with the airflow diverter 100 in the closed position, air discharged from the recirculation fan 94 flows in a reverse direction through the booster fan 96 to clean the fresh air filter 50.

While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.