Vehicular air conditioning system and control method thereof

Abstract

A vehicular air conditioning system and a control method thereof are provided. The vehicular air conditioning system includes: a plurality of mode doors configured to switch an air discharge mode in a passenger compartment, the mode doors including a defogging door, a vent door and a floor door; and a mode door air pressure reduction part configured to temporarily reduce an air pressure acting on at least one of the mode doors when the air discharge mode is switched.

Claims

1. A vehicular air conditioning system, comprising: a plurality of mode doors configured to switch an air discharge mode in a passenger compartment, the mode doors including a defogging door, a vent door and a floor door; and a mode door air pressure reduction part configured to temporarily reduce an air pressure acting on at least one of the mode doors when the air discharge mode is switched.

2. The system of claim 1, wherein the mode door air pressure reduction part is configured to temporarily reduce an air pressure acting on the defogging door for controlling an air discharged toward a window pane, when the air discharge mode is switched from a mode in which the air is discharged toward portions other than the window pane to a mode in which the air is discharged toward the window pane.

3. The system of claim 2, wherein the mode door air pressure reduction part is configured to temporarily reduce the air pressure acting on the defogging door, when the air discharge mode is switched from a floor mode in which the air is discharged toward a floor surface in the passenger compartment to a mixed mode in which the air is discharged toward the window pane and the floor surface in the passenger compartment.

4. The system of claim 3, further comprising: a mode cam configured to adjust positions of the mode doors depending on rotational positions thereof to realize a specific air discharge mode, wherein the mode cam has a plurality of slots for adjusting the positions of the mode doors as the mode cam rotates, and the mode door air pressure reduction part includes the slots of the mode cam formed such that when the mode cam is rotated to a specific position to switch the air discharge mode from the floor mode to the mixed mode, the vent door is temporarily opened to discharge a part of the air acting on the defogging door toward a face vent.

5. The system of claim 4, wherein the mode door air pressure reduction part includes a vent door slot formed in the mode cam to adjust a position of the vent door, and the vent door slot has a trajectory for temporarily opening the vent door when the mode cam is rotated to a specific position to switch the air discharge mode from the floor mode to the mixed mode.

6. The system of claim 5, wherein the trajectory of the vent door slot in a specific slot section for controlling the position of the vent door from a floor mode position to a mixed mode position is bent away from a rotation center axis of the mode cam such that in the specific slot section, the vent door is moved in such a direction as to temporarily open the face vent.

7. The system of claim 6, wherein the trajectory of the vent door slot of the mode cam is set such that when the switching of the air discharge mode from the floor mode to the mixed mode is completed, the vent door returns to an original position at which the face vent is closed.

8. The system of claim 3, further comprising: a plurality of actuators configured to adjust positions of the mode doors in response to a control signal to realize a specific air discharge mode, wherein the mode door air pressure reduction part includes a controller configured to control the actuators such that when the air discharge mode is switched from the floor mode to the mixed mode, the vent door is controlled to temporarily open a face vent to discharge a part of the air acting on the defogging door toward the face vent.

9. The system of claim 8, wherein the controller is configured to control the actuators such that when the switching of the air discharge mode from the floor mode to the mixed mode is completed, the vent door returns to an original position at which the face vent is closed.

10. The system of claim 1, wherein the mode door air pressure reduction part is configured to temporarily reduce an air pressure acting on the floor door for controlling an air discharged toward a floor surface in the passenger compartment, when the air discharge mode is switched from a mixed mode in which the air is discharged toward a window pane and the floor surface in the passenger compartment to a defogging mode in which the air is discharged toward the window pane.

11. The system of claim 10, further comprising: a mode cam configured to adjust positions of the mode doors depending on rotational positions thereof to realize a specific air discharge mode, wherein the mode cam has a plurality of slots for adjusting the positions of the mode doors as the mode cam rotates, and the mode door air pressure reduction part includes the slots of the mode cam formed such that when the mode cam is rotated to a specific position to switch the air discharge mode from the mixed mode to the defogging mode, the vent door is temporarily opened to discharge a part of the air acting on the floor door toward a face vent.

12. The system of claim 11, wherein the mode door air pressure reduction part includes a vent door slot formed in the mode cam to adjust a position of the vent door, and the vent door slot has a trajectory for temporarily opening the vent door when the mode cam is rotated to a specific position to switch the air discharge mode from the mixed mode to the defogging mode.

13. The system of claim 12, wherein the trajectory of the vent door slot in a specific slot section for controlling the position of the vent door from the mixed mode to the defogging mode is bent away from a rotation center axis of the mode cam such that in the specific slot section, the vent door is moved in such a direction as to temporarily open the face vent.

14. The system of claim 13, wherein the trajectory of the vent door slot of the mode cam is set such that when the switching of the air discharge mode from the mixed mode to the defogging mode is completed, the vent door returns to an original position at which the face vent is closed.

15. The system of claim 10, further comprising: a plurality of actuators configured to adjust positions of the mode doors in response to a control signal to realize a specific air discharge mode, wherein the mode door air pressure reduction part includes a controller configured to control the actuators such that when the air discharge mode is switched from the mixed mode to the defogging mode, the vent door is controlled to temporarily open a face vent to discharge a part of the air acting on the floor door toward the face vent.

16. The system of claim 15, wherein the controller is configured to control the actuators such that when the switching of the air discharge mode from the mixed mode to the defogging mode is completed, the vent door returns to an original position at which the face vent is closed.

17. A control method of a vehicular air conditioning system including a plurality of mode doors configured to switch an air discharge mode in a passenger compartment, the mode doors including a defogging door, a vent door and a floor door, the method comprising: a) determining whether an air discharge mode is switched from a mode in which an air is discharged toward portions other than a window pane to a mode in which the air is discharged toward the window pane; and b) temporarily opening the vent door in response to the air discharge mode being switched from the mode in which the air is discharged toward the portions other than the window pane to the mode in which the air is discharged toward the window pane so as to temporarily reduce an air pressure acting on the defogging door for controlling an air discharged toward a window pane.

18. The control method of claim 17, wherein in a), it is determined whether the air discharge mode is switched from a floor only mode in which the air is discharged toward a floor surface in the passenger compartment to a mixed mode in which the air is discharged toward the window pane and the floor surface in the passenger compartment.

19. The control method of claim 18, wherein in response to determining in a) that the air discharge mode is switched from the floor mode to the mixed mode, the vent door is moved b) to temporarily open a face vent at a timing at which the air discharge mode is switched from the floor mode to the mixed mode.

20. The control method of claim 17, wherein in response to the air discharge mode from the floor mode to the mixed mode being completed during b), the vent door is returned to an original position at which the face vent is closed.

21. A control method of a vehicular air conditioning system including a plurality of mode doors configured to switch an air discharge mode in a passenger compartment, the mode doors including a defogging door, a vent door and a floor door, the method comprising: a) determining whether an air discharge mode is switched from a mixed mode in which an air is discharged toward a window pane and a floor surface in the passenger compartment to a defogging mode in which the air is discharged toward the window pane; and b) temporarily opening the vent door in response to the air discharge mode being switched from the mixed mode to the defogging mode so as to temporarily reduce an air pressure acting on the defogging door for controlling an air discharged toward a window pane.

22. The control method of claim 21, wherein in response to the air discharge mode from the mixed mode to the defogging mode being completed during b), the vent door is returned to an original position at which the face vent is closed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a view showing a conventional vehicular air conditioning system.

(2) FIG. 2 is a view showing different air discharge modes controlled by the conventional vehicular air conditioning system.

(3) FIG. 3 is a view showing the configuration of a vehicular air conditioning system according to the present invention.

(4) FIGS. 4A and 4B are views showing a conventional mode cam and a mode cam as a mode door air pressure reduction part constituting the vehicular air conditioning system according to the present invention.

(5) FIGS. 5A, 5B and 5C are views showing an operation example of the vehicular air conditioning system according to the present invention, in which a vent door is temporarily opened when a floor mode is switched to a mixed mode.

(6) FIGS. 6A, 6B and 6C are views showing an operation example of the vehicular air conditioning system according to the present invention, in which a vent door is temporarily opened when a mixed mode is switched to a defogging mode.

(7) FIG. 7 is a view showing another example of the mode door air pressure reduction part constituting the vehicular air conditioning system according to the present invention.

(8) FIG. 8 is a flowchart illustrating a vehicular air conditioning system control method according to the present invention, in which a floor mode is switched to a mixed mode.

(9) FIG. 9 is a flowchart illustrating a vehicular air conditioning system control method according to the present invention, in which a mixed mode is switched to a defogging mode.

DETAILED DESCRIPTION

(10) Preferred embodiments of a vehicular air conditioning system and a control method according to the present invention will now be described in detail with reference to the accompanying drawings.

(11) Prior to describing features of a vehicular air conditioning system and a control method according to the present invention, a vehicular air conditioning system will be briefly described with reference to FIGS. 2 and 3.

(12) The vehicular air conditioning system includes mode doors 10, 12 and 14. The mode doors 10, 12 and 14 include a defogging door 10, a vent door 12 and a floor door 14.

(13) These mode doors 10, 12 and 14 are operated to cooperate with each other to adjust the discharge direction of the air supplied into a passenger compartment.

(14) In particular, as shown in FIG. 2, the mode doors 10, 12 and 14 are controlled in a vent mode M1, a bi-level mode M2, a floor mode M3, a mixed mode M4, a defogging mode M5 and the like, thereby controlling the discharge mode of the air supplied into the passenger compartment.

(15) Even if the mode doors 10, 12 and 14 are controlled in the floor mode M3, the defogging door 10 is opened by a predetermined amount. Therefore, even in the floor mode M3, a predetermined amount of air is discharged toward the window pane in the passenger compartment.

(16) Usually, in the floor mode M3, the air volume distribution ratio of a floor vent 14a to a defogging vent 10a is 80:20. Therefore, in the floor mode M3, about 20% of the air is discharged to the upper portion of the passenger compartment through the defogging vent 10a.

(17) Next, the features of the vehicular air conditioning system according to the present invention will be described in detail with reference to FIGS. 3 to 6.

(18) Referring first to FIG. 3, the vehicular air conditioning system according to the present invention further includes a mode door air pressure reduction part 20 capable of reducing the air pressure acting on at least one of the mode doors 10, 12 and 14 when a specific air discharge mode (hereinafter referred to as an “existing air discharge mode” is switched to a new air discharge mode).

(19) The mode door air pressure reduction part 20 is configured to reduce the air pressure acting on the defogging door 10, for example, when the floor mode M3 in which the air is discharged toward the floor surface in the passenger compartment is switched to the mixed mode M4 in which the air is discharged toward the window pane and the floor surface in the passenger compartment (see FIG. 2).

(20) The mode door air pressure reduction part 20 includes a mode cam 22 for controlling the respective positions of the mode doors 10, 12 and 14.

(21) As shown in FIG. 4, the mode cam 22 has a plurality of slots 22a, 22b and 22c capable of controlling the positions of the mode doors 10, 12 and 14. By improving the trajectory shapes of the slots 22a, 22b and 22c, when the air discharge mode is switched from the floor mode M3 to the mixed mode M4, the vent door 12 is controlled so as to be temporarily opened by a predetermined amount as shown in FIG. 5.

(22) In particular, as shown in FIG. 4, by improving the trajectory of the vent door slot 22a for controlling the position of the vent door 12 among the slots 22a, 22b and 22c of the mode cam 22, when the air discharge mode is switched from the floor mode M3 to the mixed mode M4, the position of the vent door 12 is controlled in a such direction as to temporarily open the face vent 12a.

(23) More specifically, when the air discharge mode is switched from the floor mode M3 to the mixed mode M4, the vent door 12 is controlled in such a direction as to be temporarily opened.

(24) Therefore, as shown in FIG. 5, the air in an air conditioning case 19 is discharged toward the face vent 12a when the air discharge mode is switched from the floor mode M3 to the mixed mode M4. Thus, the internal air pressure of the air conditioning case 19 is temporarily reduced.

(25) As a result, the air pressure acting on the defogging door 10 is temporarily reduced at the time of switching the air discharge mode from the floor mode M3 to the mixed mode M4. Accordingly, the excessive air pressure acting on the defogging door 10 is eliminated when the air discharge mode is switched from the floor mode M3 to the mixed mode M4.

(26) Accordingly, when switching the air discharge mode from the floor mode M3 to the mixed mode M4, all the mode doors 10, 12 and 14 including the defogging door 10 can be controlled to move from floor mode positions to mixed mode positions without the need for a large startup torque.

(27) Thus, when the mode cam 22 is rotated through cable traction and the mode doors 10, 12 and 14 are controlled through the mode cam 22, the mode cam 22 can be easily rotated from a floor mode position to a mixed mode position. As a result, the operation feeling of a rotary knob (not shown) for rotating the mode cam 22 can be remarkably improved.

(28) Preferably, as shown in FIG. 4B, the shape of the trajectory of the vent door slot 22a of the mode cam 22 in a specific slot section A for controlling the position of the vent door 12 from a floor mode position to a mixed mode position is improved so that the trajectory of the vent door slot 22a in the specific slot section A is bent away from the rotation center axis 22d of the mode cam 22.

(29) Therefore, when the air discharge mode is switched from the floor mode M3 to the mixed mode M4, the connecting pin 12b of the vent door 12 sliding along the vent door slot 22a is moved radially outward while passing through the specific slot section A of the vent door slot 22a.

(30) Thus, as shown in FIG. 5, when the air discharge mode is switched from the floor mode M3 to the mixed mode M4, the vent door 12 rotates at a predetermined angle in such a direction as to open the face vent 12a.

(31) Preferably, the trajectory of the vent door slot 22a in the specific slot section A has such a shape that the vent door 12 is opened at an angle of about 5° from a position at which the face vent 12a is completely closed.

(32) In addition, the trajectory of the vent door slot 22a in the specific slot section A has such a shape that when the switching of the air discharge mode from the floor mode M3 to the mixed mode M4 is completed, the vent door 12 returns to its original position where the face vent 12a is completely closed.

(33) Referring back to FIG. 3, the mode door air pressure reduction part 20 is also configured to reduce the air pressure acting on the floor door 14 when the air discharge mode is switched from the mixed mode M4 for discharging the air toward the window pane and the floor surface in the passenger compartment to the defogging mode M5 for discharging the air toward the window pane (see FIG. 2).

(34) To this end, in the mode cam 22 of the mode door air pressure reduction part 20, as shown in FIG. 4B, the trajectory shapes of the slots 22a, 22b and 22c are improved such that when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, the vent door 12 is temporarily opened by a predetermined amount as shown in FIG. 6.

(35) In particular, as shown in FIG. 4B, by improving the trajectory of the vent door slot 22a for controlling the position of the vent door 12 among the slots 22a, 22b and 22c of the mode cam 22, when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, the position of the vent door 12 is controlled in such a direction as to temporarily open the face vent 12a by a predetermined amount.

(36) More specifically, by improving the shape of the trajectory of the vent door slot 22a in a specific slot section B for controlling the position of the vent door 12 from the mixed mode position to the defogging mode position, when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, the vent door 12 is controlled to be temporarily opened.

(37) Therefore, as shown in FIG. 6, when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, the air in the air conditioning case 19 is partially discharged toward the face vent 12a. Thus, the internal air pressure of the air conditioning case 19 is temporarily reduced.

(38) As a result, the air pressure acting on the floor door 14 is temporarily reduced when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5. This makes it possible to eliminate the excessive air pressure acting on the floor door 14 when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5.

(39) Thus, the floor door 14 can be completely closed when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5.

(40) In addition, when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, the excessive air pressure acting on the floor door 14 is eliminated. Thus, when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, all the mode doors 10, 12 and 14 including the floor door 14 can be controlled to move from the mixed mode positions to the defogging mode positions without the need for a large startup torque.

(41) Thus, when the mode cam 22 is rotated through cable traction and the mode doors 10, 12 and 14 are controlled through the mode cam 22, it is very easy to rotate the mode cam 22 from the mixed mode M4 to the defogging mode M5. As a result, the operation feeling of the rotary knob (not shown) for rotating the mode cam 22 can be remarkably improved.

(42) Preferably, as shown in FIG. 4B, the shape of the trajectory of the vent door slot 22a of the mode cam 22 in a specific slot section B for controlling the position of the vent door 12 from a mixed mode position to a defogging mode position is improved so that the trajectory of the vent door slot 22a in the specific slot section B is bent away from the rotation center axis 22d of the mode cam 22.

(43) Therefore, when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, the connecting pin 12b of the vent door 12 sliding along the vent door slot 22a is moved radially outward while passing through the specific slot section B of the vent door slot 22a.

(44) Thus, as shown in FIG. 6, when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, the vent door 12 rotates at a predetermined angle in such a direction as to open the face vent 12a.

(45) Preferably, the trajectory of the vent door slot 22a in the specific slot section B has such a shape that the vent door 12 is opened at an angle of about 5° from a position at which the face vent 12a is completely closed.

(46) In addition, the trajectory of the vent door slot 22a in the specific slot section B has such a shape that when the switching of the air discharge mode from the mixed mode M4 to the defogging mode M5 is completed, the vent door 12 returns to its original position where the face vent 12a is completely closed.

(47) Next, another example of the mode door air pressure reduction part 20 constituting the vehicular air conditioning system according to the present invention will be described with reference to FIG. 7.

(48) In the mode door air pressure reduction part 20 according to another example, the driving device for driving the respective mode doors 10, 12 and 14 is an actuator type. The driving device includes a vent door actuator 30 for controlling the position of the vent door 12 and a controller 32 for controlling the vent door actuator 30.

(49) The vent door actuator 30 is operated in response to a control signal applied thereto. The vent door actuator 30 controls the vent door 12 to move to a vent mode position, a bi-level mode position, a floor mode position, a mixed mode position and a defogging mode position (see FIG. 2).

(50) Particularly, upon receiving a signal indicating the switching of the air discharge mode from the floor mode M3 to the mixed mode M4, the vent door actuator 30 moves the vent door 12 from the floor mode position to the mixed mode position.

(51) In addition, upon receiving a signal indicating the switching of the air discharge mode from the mixed mode M4 to the defogging mode M5, the vent door actuator 30 moves the vent door 12 from the mixed mode position to the defogging mode position.

(52) The controller 32 is equipped with a microprocessor. The controller 32 controls the vent door actuator 30 so as to temporarily open the vent door 12 when the air discharge mode is switched from the floor mode M3 to the mixed mode M4.

(53) In particular, as shown in FIG. 5, when the air discharge mode is switched from the floor mode M3 to the mixed mode M4, the controller 32 controls the vent door actuator 30 so as to move the vent door 12 in such a direction as to temporarily open the face vent 12a.

(54) Accordingly, when the air discharge mode is switched from the floor mode M3 to the mixed mode M4, the air in the air conditioning case 19 is discharged toward the face vent 12a, whereby the air pressure in the air conditioning case 19 is temporarily reduced.

(55) As a result, when the air discharge mode is switched from the floor mode M3 to the mixed mode M4, the air pressure acting on the defogging door 10 is temporarily reduced to eliminate the excessive air pressure acting on the defogging door 10.

(56) Therefore, when switching the air discharge mode from the floor mode M3 to the mixed mode M4, the defogging door 10 can be controlled to move from the floor mode position to the mixed mode position without the need for a large startup torque.

(57) This reduces the driving load of a defogging door actuator (not shown) for driving the defogging door 10.

(58) On the other hand, when the switching of the air discharge mode from the floor mode M3 to the mixed mode M4 is completed, the controller 32 controls the vent door actuator 30 so that the vent door 12 returns to the original position where the face vent 12a is completely closed.

(59) When the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, the controller 32 controls the vent door actuator 30 so as to temporality open the vent door 12.

(60) In particular, as shown in FIG. 6, when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, the controller 32 controls the vent door actuator 30 so as to move the vent door 12 in such a direction as to temporarily open the face vent 12a in a predetermined amount.

(61) Therefore, when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, the air in the air conditioning case 19 is discharged toward the face vent 12a, whereby the air pressure in the air conditioning case 19 is temporarily reduced.

(62) As a result, when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, the air pressure acting on the floor door 14 is temporarily reduced to eliminate the excessive air pressure acting on the floor door 14.

(63) Accordingly, the floor door 14 can be completely closed when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5.

(64) In addition, when the air discharge mode is switched from the mixed mode M4 to the defogging mode M5, the excessive air pressure acting on the floor door 14 is eliminated. Thus, when switching the air discharge mode from the mixed mode M4 to the defogging mode M5, the floor door 14 can be controlled to move from the mixed mode position to the defogging mode position without the need for a large startup torque.

(65) This reduces the driving load of a floor door actuator (not shown) for driving the floor door 14.

(66) On the other hand, when the switching of the air discharge mode from the mixed mode M4 to the defogging mode M5 is completed, the controller 32 controls the vent door actuator 30 so that the vent door 12 returns to the original position where the face vent 12a is completely closed.

(67) Next, a vehicular air conditioning system control method according to the present invention will be described with reference to FIGS. 8 and 5.

(68) Referring first to FIG. 8, a vehicular air conditioning system control method when the floor mode M3 is switched to the mixed mode M4 will be described.

(69) The air conditioner is turned on (S101). In this state, it is determined whether the air discharge mode is the floor mode M3 (S103).

(70) If it is determined that the air conditioning mode is the floor mode M3, it is determined whether the air discharge mode is switched from the floor mode M3 to the mixed mode M4 (S105).

(71) If it is determined that the floor mode M3 is switched to the mixed mode M4, the vent door 12 is temporarily opened at the time of switching the floor mode M3 to the mixed mode M4 (S107).

(72) Then, as shown in FIG. 5, the air in the air conditioning case 19 is partially discharged toward the face vent 12a, thereby temporarily reducing the air pressure in the air conditioning case 19.

(73) As a result, the air pressure acting on the defogging door 10 is temporarily eliminated, whereby the defogging door 10 is easily controlled to move from the floor mode position to the mixed mode position without the need for a large startup torque.

(74) On the other hand, when the floor mode M3 is switched to the mixed mode M4 during step S107, the vent door 12 is temporarily opened. If the switching of the air discharge mode from the floor mode M3 to the mixed mode M4 is completed, the vent door 12 is controlled to move to its original position to close the face vent 12a.

(75) Referring next to FIG. 9, a vehicular air conditioning system control method when the mixed mode M4 is switched to the defogging mode M5 will be described.

(76) The air conditioner is first turned on (S201). In this state, it is determined whether the air discharge mode is the mixed mode M4 (S203).

(77) If it is determined that the air conditioning mode is the mixed mode M4, it is determined whether the air discharge mode is switched from the mixed mode M4 to the defogging mode M5 (S205).

(78) If it is determined that the mixed mode M4 is switched to the defogging mode M5, the vent door 12 is temporarily opened at the time of switching the mixed mode M4 to the defogging mode M5 (S207).

(79) Then, as shown in FIG. 6, the air in the air conditioning case 19 is partially discharged toward the face vent 12a, thereby temporarily reducing the air pressure in the air conditioning case 19.

(80) As a result, the air pressure acting on the floor door 14 is temporarily eliminated and the floor door 14 is completely closed, whereby the floor door 14 is easily controlled to move from the mixed mode position to the defogging mode position without the need for a large startup torque.

(81) On the other hand, when the mixed mode M4 is switched to the defogging mode M5 during step S207, the vent door 12 is temporarily opened. If the switching of the air discharge mode from the mixed mode M4 to the defogging mode M5 is completed, the vent door 12 is controlled to move to its original position to close the face vent 12a.

(82) While the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. Various modifications and changes may be made without departing from the scope and spirit of the present invention defined in the claims.