Air passage opening/closing device

A guide groove is provided on both sides in a door width direction of a plate-like portion of a door. A radius of curvature of the plate-like portion in a single non-mounted state is set more than that of the guide groove, to thereby support both end portions in the door width direction of the plate-like portion respectively at three abutment points P1 to P3. A rib is provided in the plate-like portion to extend from one end portion in the door width direction of the plate-like portion to the other end portion thereof, so that force generated from both end portions in the door width direction of the plate-like portion is transferred to a center portion in the door width direction of the plate-like portion via the rib. Therefore, it can prevent the center portion and vicinity of the plate-like portion from being deformed in the direction away from a seal surface of the air conditioning case.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Phase Application under 35 U.S.C. 371 of International Application No. PCT/JP2013/002235 filed on Apr. 1, 2013 and published in Japanese as WO 2013/150767 Al on Oct. 10, 2013. This application is based on and claims the benefit of priority from Japanese Patent Application 2012-087656 filed on Apr. 6, 2012. The entire disclosures of all of the above applications are incorporated herein by reference.

FIELD OF THE INVENTION

The present disclosure relates to an air passage opening/closing device for opening or closing an air passage by using a slide door. The air passage opening/closing device is suitable for use in an air conditioner for a vehicle.

BACKGROUND ART

A conventional air passage opening/closing device is provided with a guide groove in a case that forms an air passage. The guide groove serves to guide both end portions in the door width direction of a slide door. With this arrangement, the slide door is designed to reciprocate along the guide groove. Such a movement of the slide door opens and closes the air passage of the case.

The radius of curvature of the slide door in a single non-mounted state is set equal to or more than that of the guide groove, so that both end portions of the slide door in the door movement direction are easily brought into contact with a seal surface on a case side when assembling the slide door in the case. Thus, even under a small volume of air, the slide door is pressure-contacted with the seal surface on the case side by pressure of blown air, so as to exhibit good sealability with the slide door.

However, while the air pressure is not applied to the slide door, the slide door is not pressure-contacted with the seal surface on the case side. When the entire case vibrates in this state, both end portions in the door movement direction of the slide door might vibrate, causing abnormal sound (noise) from the slide door.

An air passage opening/closing device disclosed in Patent Document 1 is provided with a guide groove composed of a windward sidewall portion and a leeward sidewall portion. The sidewall portions are respectively provided on both sides of the slide door in the door width direction. The radius of curvature of the slide door in a single non-mounted state is set equal to or more than that of each of the windward sidewall portion and the leeward sidewall portion. As a result, the center portion of the slide door in the door movement direction is pushed against the windward sidewall portion by an elastic deformation force of the door, while both end portions of the slide door in the door movement direction are pushed against the leeward sidewall by the elastic deformation force of the door. In this way, the slide door is supported at three points, including the center portion and both the end portions of the door in the door movement direction, thereby suppressing the vibration of both end portions of the slide door in the door movement direction.

RELATED ART DOCUMENT

Patent Document

SUMMARY OF INVENTION

However, the inventors of the present application have found through their studies that when an aspect ratio of the slide door (=dimension in the door movement direction of the slide door/dimension in the door width direction of the slide door) is approximately ½ (one half) or less, the slide door generates abnormal sounds (noise).

That is, as shown inFIG. 8, when assembling a slide door100in a guide groove110, the slide door100has both end portions thereof in the width direction supported in the following manner. A center portion of the slide door100in the door movement direction is abutted against a windward sidewall portion110aof the guide groove110at an abutment point P1, while both end portions of the slide door100in the door movement direction are abutted against a leeward sidewall portion110bof the guide groove110at abutment points P2and P3. In this way, the slide door100is elastically bent and deformed to be supported at three points, namely, the abutment points P1to P3.

On the other hand, as the aspect ratio of the slide door100is decreased, the elastic deformation force generated at both end portions in the door movement direction is less likely to be transferred toward the center portion in the door width direction of the slide door100. In this case, as shown inFIG. 9, the center portion in the door width direction of the slide door100gets closer to the shape (that is, a substantially flat plate) in the single non-mounted state. The center portion in the door width direction of the slide door100located near the center portion in the door movement direction of the door (that is, the center and vicinity of the slide door100) is positioned on the windward side with respect to even both end portions thereof in the door width direction, and thereby it causes the center and vicinity of the slide door100to float from the seal surface on the case side. As a result, both end portions in the door width direction of the slide door100supported at three points serve as a node, while the center and vicinity of the slide door100floating from the seal surface on the case side serve as a main central part, causing the slide door100to vibrate to generate abnormal sound (noise).

As measures against this problem, a packing is added to press the slide door100against the seal surface on the case side, so that the slide door100is pressure-contacted with the seal surface on the case side even while the air pressure is not applied to the slide door100. Such measures, however, use the packing as a different part, leading to an increase in cost.

The present disclosure has been made in view of the foregoing matters, and it is an object of the present disclosure to provide an air passage opening/closing device that can suppress vibration of a center portion in the door width direction of the slide door without increasing the number of parts of the device.

According to one exemplary embodiment of the present disclosure, an air passage opening/closing device includes a case forming an air passage, a slide door including a plate-like portion slidably disposed in the case and being adapted to open and close the air passage by the plate-like portion, and a guide groove. The guide groove includes a windward sidewall portion formed in the case to extend in a door movement direction on a windward side with respect to the plate-like portion, and a leeward sidewall portion formed in the case to be opposed to the windward sidewall portion on a leeward side with respect to the plate-like portion, and the guide groove guides a movement of the plate-like portion by the windward sidewall portion and the leeward sidewall portion. The guide groove is disposed at both sides of the plate-like portion in a door width direction, and a radius of curvature of the plate-like portion in a single non-mounted state is set more than a radius of curvature of each of the windward sidewall portion and the leeward sidewall portion, In addition, a center portion in the door movement direction of the plate-like portion is abutted against one of the windward sidewall portion and the leeward sidewall portion, and an end portion in the door movement direction of the plate-like portion is abutted against the other one of the windward sidewall portion and the leeward sidewall portion, such that the plate-like portion is elastically deformed, when the plate-like portion is disposed in the case. In addition, the plate-like portion is provided with a rib that extends from one end portion of the plate-like portion to the other end portion of the plate-like portion in the door width direction.

With this arrangement, force generated from both end portions in the door width direction of the plate-like portion is transferred to the center portion in the door width direction of the plate-like portion via the rib, so that it can prevent deformation at the center portion and vicinity of the plate-like portion in the direction away from a seal surface on the case side. In this way, the center portion in the door width direction of the plate-like portion is elastically bent and deformed in the same manner as both end portions in the door width direction of the plate-like portion supported at three points, so that the center portion and vicinity of the plate-like portion can be pressed against the seal surface on the case side to suppress vibration of the center portion in the door width direction of the plate-like portion.

DESCRIPTION OF EMBODIMENTS

In the following, preferred embodiments of the present disclosure will be described with reference to the accompanying drawings. The same or equivalent parts in the embodiments below are indicated by the same reference characters throughout the figures.

A first embodiment of the present disclosure will be described below. In this embodiment, an air passage opening/closing device of the present disclosure is applied to a vehicle air conditioner. Referring toFIGS. 1 and 2, the upper, lower, front, back, left, and right arrows indicate respective directions of the air passage opening/closing device in a vehicle-mounted state.

An interior air conditioning unit10is disposed in a substantially center area of the vehicle in left and right directions (in a door width direction of the vehicle) inside a dashboard (instrument panel) located at the forefront part of the vehicle interior. The interior air conditioning unit10forms an outer shell therefor, and includes an air conditioning case11for forming an air passage of air for an interior to be blown into the vehicle interior. The air conditioning case11is formed of resin (for example, polypropylene) having some degree of elasticity, and excellent strength.

The air conditioning case11has a division surface formed at the substantially center portion in the left-right direction of the vehicle, and extending in the up-down direction of the vehicle. The division surface can divide the interior of the air conditioning case11into two left and right portions. The two left and right division portions are integrally coupled together by a connection means, such as a metal spring, a clip, or a screw, while accommodating therein respective components including an air filter14, an evaporator13, a heater core15as will be described later.

As shown inFIG. 1, an inside/outside air switch12for switching between inside air (air in the vehicle interior) and outside air (air outside a vehicle compartment) to introduce the switched air into the air conditioning case is provided in the most upstream portion of the air passage formed in the air conditioning case11and on the vehicle front side and the upper side of the air conditioning case11. The inside/outside air switch12has an inside air introduction port11afor introducing inside air into the air conditioning case11, and an outside air introduction port11bfor introducing outside air into the air conditioning case11.

An inside/outside air switching door12bis rotatably positioned inside the inside/outside air switch12to open and close the inside air introduction port11aand the outside air introduction port11b. Specifically, the inside/outside air switching door12bis a so-called cantilever door which includes a plate-like door main portion12c, and a rotary shaft12aintegrally coupled to one end portion of the main portion12cand extending in the left-right direction of the vehicle.

The inside/outside air switching door12is adapted to rotate the rotary shaft12aby a servo motor (not shown) to displace the door main portion12cby the rotation to thereby continuously enable adjustment of the opening areas of the inside air introduction port11aand the outside air introduction port11b. The evaporator13is disposed on the downstream side of an air flow of the inside/outside air switch12.

The evaporator13is one of the components included in the well-known evaporation compression refrigeration cycle (not shown). The evaporator13is a heat exchanger for cooling that cools the air to be blown into the interior by evaporating the low-pressure refrigerant in the refrigeration cycle to exhibit a heat absorption effect.

The evaporator13includes a core13acomposed of a plurality of tubes and a heat exchanging fin, and tanks13bdisposed on both ends of the core13ato constitute a flat shape as a whole. The evaporator13has flattened surfaces (flat surfaces) thereof disposed in parallel with the vertical or up-down direction of the vehicle.

The tubes are arranged in parallel with the up-down direction and adapted to allow the refrigerant to flow therethrough. The heat exchanging fin promotes heat exchange between air and refrigerant in the tubes. The tanks13bare respectively disposed on the upper and lower sides of the tubes, and adapted to distribute the refrigerant to the tubes and to collect the refrigerants from the tubes. Both the upper and lower tanks13band13bare supported by the air conditioning case11.

The thin, plate-like air filter14is disposed on the air upstream side of the evaporator13inside the air conditioning case11. The air filter14is adapted to remove dust and the like from the air flowing into the evaporator13.

A heater core15is disposed on the rear and upper sides of the vehicle positioned on the downstream side of the air flow of the evaporator13. The heater core15is a heat exchanger for heating that exchanges heat between the air cooled by the evaporator13and a high-temperature engine coolant having circulating through an engine coolant circuit (not shown) and flowing into the core to thereby re-heating the cooled air.

Like the evaporator13, the heater core15includes a core15acomposed of a plurality of tubes and a heat exchanging fin, and tanks15bdisposed on both ends of the core15ato constitute a flat shape as a whole. The heater core15is disposed in substantially parallel with the evaporator13. In this embodiment, the heater core15is disposed such that the upper end portion of the heater core15is positioned slightly close to the front side with respect to the lower end portion thereof with a flat surface of the heater core15inclined respective to a flat surface of the evaporator13by a predetermined angle (of less than about 30 degrees).

The tubes are disposed substantially in the up-down direction along the inclination angle of the heater core15. The upper tank15bdistributes the refrigerant to the tubes13a. The lower tank15bcollects the refrigerants from the tubes13a. Both the upper and lower tanks15band15bare respectively supported by the air conditioning case11.

Then, a bypass passage16is formed behind the evaporator13and under the heater core15. The bypass passage16is a passage for allowing the flow of the cooled air having passed through the evaporator13to bypass the heater core15.

Directly after the evaporator13, an air mix door60is disposed for adjusting the ratio of the volume of the cooled air flowing into the heater core15to that of the cooled air flowing into the bypass passage16. The air mix door60is constructed of a slide door which includes a plate-like portion61extending curved in an arc shape in the up-down direction of the vehicle, a gear mechanism62for driving and displacing the plate-like portion61in the curved direction, and a rib63extending from one end in the door width direction of the plate-like portion61to the other end thereof, and having a rigidity higher than the plate-like portion61(seeFIG. 3to be described in detail later).

The plate-like portion61of the air mix door60is moved (slided) in the upward direction of the vehicle, thereby increasing an opening degree of the passage on the bypass passage16side, while decreasing an opening degree of the passage on the heater core15side. In contrast, the plate-like portion61of the air mix door60is moved (slided) in the downward direction of the vehicle, thereby decreasing an opening degree of the passage on the bypass passage16side, while increasing an opening degree of the passage on the heater core15side.

Such adjustment of the opening degree of the air mix door60adjusts the ratio of the volume of the cooled air sucked into a blower20to that of the warmed air sucked thereinto, and thereby it can control the temperature of the air for the interior to be blown into the vehicle interior. That is, the air mix door60constitutes temperature adjustment means for the interior air.

The gear mechanism62includes racks62aprovided in the plate-like portion61to extend in the door movement direction, and pinions62bengaged with the racks62a. The pinion62bis driven by a servo motor (not shown). In this embodiment, the rack62aand the pinion62bare disposed on the windward side of the plate-like portion61.

The racks62aand pinions62bare disposed near both end portions in the door width direction of the plate-like portion61. Specifically, the racks62aand pinions62bare disposed on the slightly inner side with respect to both end portions in the door width direction of the plate-like portion61.

The air conditioning case11is provided with guide grooves53for guiding the movement of the plate-like portion61. The guide grooves53are disposed on both sides of the plate-like portion61in the door width direction. Each guide groove53includes a windward sidewall portion53aextending in the door movement direction on the windward side with respect to the plate-like portion61, and a leeward sidewall portion53bpositioned on the leeward side with respect to the plate-like portion61and opposed to the windward sidewall portion53a.

Both end portions in the door width direction of the plate-like portion61, that is, parts of the plate-like portion61outside the respective rack62ain the door width direction can be slidably inserted into between the windward sidewall portion53aand the leeward sidewall portion53b. In this way, the movement of the plate-like portion61is guided by the guide grooves53each having the windward sidewall portion53aand the leeward sidewall portion53b.

The blower20is disposed below the heater core15inside the air conditioning case11. As shown inFIGS. 1 and 2, the blower20includes an electric motor21, impellers22and23, and scroll cases24aand24b. The electric motor21is disposed at the center portion in the left-right direction of the vehicle within the air conditioning case11. The rotary shaft of the electric motor21respectively extends toward both sides in the left-right direction of the vehicle.

The impellers22and23are a centrifugal multiblade fan. The impeller22is fixed to the left tip end of the rotary shaft of the electric motor21. The impeller22includes a fan portion22awith a number of blades arranged around the rotary shaft and which is adapted to suck air thereinto from the left side in the axial direction and to blow the air out toward the outside in the radial direction as indicated by the arrow Ka ofFIG. 2. The impeller22also includes a fan portion22bwith a number of blades arranged around the rotary shaft, and which is adapted to suck air thereinto from the right side in the axial direction and to blow the air out toward the outside in the radial direction as indicated by the arrow Kb ofFIG. 2. The impeller22further includes a partition wall22cfor partitioning the inside of the impeller into the fan portions22aand22b. With this arrangement, the impeller22can suck the air from both sides in the rotary shaft direction to blow the air out toward the outside in the radial direction.

The impeller23is fixed to the right tip end portion of the rotary shaft of the electric motor21. Like the impeller22, the impeller23includes a fan portion23awith a number of blades arranged around the rotary shaft and which is adapted to suck air thereinto from the left side in the axial direction and to blow the air out toward the outside in the radial direction. The impeller23also includes a fan portion23bwith a number of blades arranged around the rotary shaft and which is adapted to suck air thereinto from the right side in the axial direction and to blow the air out toward the outside in the radial direction. The impeller23further includes a partition wall23cfor partitioning the inside of the impeller into the fan portions23aand23b. With this arrangement, the impeller23can suck the air from both sides in the rotary shaft direction to blow the air out toward the outside in the radial direction.

The scroll case24aindividually accommodates therein the fan portions22aand22bof the impeller22, and forms an outflow air passage for allowing the air having flowed from the fan portions22aand22bto flow therethrough. The scroll case24ais formed in a spiral pattern that gradually enlarges a sectional area of the outflow air passage in the rotational direction of the impeller22. The scroll case24aincludes two suction ports respectively provided on both sides thereof in the rotary shaft direction, and an air outlet for blowing upward the air fed from the impeller22.

The scroll case24bindividually accommodates therein the fan portions23aand23bof the impeller22, and forms an outflow air passage for allowing the air having flowed from the fan portions23aand23bto flow therethrough. The scroll case24bis formed in a spiral pattern that gradually enlarges a sectional area of the outflow air passage in the rotational direction of the impeller23. The scroll case24bincludes two suction ports respectively provided on both sides thereof in the rotary shaft direction, and an air outlet for blowing upward the air fed from the impeller23.

As shown inFIG. 1, a partition wall18is formed in a curved shape on the vehicle rear side of the heater core15inside the air conditioning case11. The partition wall18serves as a guide wall that guides the warm air blown from the heater core15toward the blower20side.

Inside the air conditioning case11, an air passage40is provided between the partition wall18and the rear wall (outer wall)30to guide the air blown from the scroll cases24aand24bto air outlets35and36. The air outlet36is provided in a vehicle rear part of the upper surface of the air conditioning case11. The air outlet36is a face opening for blowing the air flow having passed through an air passage40toward the upper body of the passenger.

The air outlet35is provided on a vehicle front side of the upper surface of the air conditioning case11with respect to the air outlet36. The air outlet35is a defroster opening for blowing the air flow having passed through the air passage40toward an inner surface of a front glass of the vehicle. An air-outlet mode door54is disposed on the inner side of the air outlets35and36of the air conditioning case11. The air outlets35and36are disposed on the upper side in the vertical direction with respect to the blower20.

The air-outlet mode door54is the same type of slide door as the air mix door60. The air-outlet mode door54includes a plate-like portion55extending curved in an arc shape toward the rear side of the vehicle, and a gear mechanism56for driving and displacing the plate-like portion55in the curved direction.

The plate-like portion55of the air outlet mode door54is moved (slided) toward the front side of the vehicle, thereby increasing an opening degree of the passage on the air outlet36side, while decreasing an opening degree of the passage on the air outlet35side. Conversely, the plate-like portion55is moved (slided) toward the rear side of the vehicle, thereby increasing an opening degree of the passage on the air outlet35side, while decreasing an opening degree of the passage on the air outlet36side.

The gear mechanism56of the air-outlet mode door54includes racks and pinions, like the gear mechanism62of the air mix door60. A guide groove57for guiding the movement of the plate-like portion55of the air-outlet mode door54includes a windward sidewall portion57apositioned on the windward side of the plate-like portion55and a leeward sidewall portion57bpositioned on the leeward side of the plate-like portion55, like the guide groove53of the air mix door60.

As shown inFIG. 1, the rear wall30of the air conditioning case11is provided with a rear-seat side foot opening39. The rear-seat side foot opening39allows the air flow having passed through the air passage40to blow toward a passenger's foot on the rear seat. As shown inFIG. 2, the air conditioning case11is provided with a front seat side foot opening41. The front seat side foot opening41allows the air flow having passed through the air passage40to blow toward a passenger's foot on the front seat. The foot openings39and41are disposed on the upper side in the vertical direction with respect to the blower20.

A foot door42is disposed inside the foot openings39and41in the air conditioning case11. The foot door42is a so-called butterfly door which includes a plate-like door main portion42b, and a rotary shaft42aintegrally coupled to the substantially center portion of the door main portion42band extending in the front-back direction of the vehicle. The rotary shaft42ais rotated by a servo motor (not shown) to rotate and displace the door main portion42b, thereby opening and closing the foot openings39and41.

Next, the operation of the interior unit10of this embodiment will be described. First, the electric motor21of the blower20rotatably drives the respective impellers22and23. Then, the impeller22sucks the air from both suction ports of the scroll case24ato blow out the air from the air outlet of the scroll case24a.

Then, the impeller23sucks the air from both suction ports of the scroll case24bto blow out the air from the air outlet of the scroll case24b. Such an operation of the blower20introduces air into the air conditioning case11via at least one of the inside air introduction port11aand the outside air introduction port11b.

The air introduced from one introduction port flows into the evaporator13through the air filter14. When passing through the evaporator13, the air exchanges heat with the refrigerant to be cooled so as to become a cooled air.

While the air mix door60respectively opens the air inlet of the bypass passage16and the air inlet of the heater core15, a part of cooled air blown from the evaporator13flows into the heater core15side to be heated by the heater core15. In this way, the warm air is blown out of the heater core15.

The warm air is guided by the partition wall18toward the blower20side to flow as indicated by the arrow ra ofFIG. 1. The remaining part of the cooled air blown from the evaporator13passes through the bypass passage16to flow as indicated by the arrow rb ofFIG. 1.

Together with this, the cooled air passing through the bypass passage16and the warm air blown from the heater core15flow toward both suction ports of the scroll case24a. The cooled air and the warm air collide with each other at an angle of about 90 degrees before being sucked into the suction ports. The cooled air passing through the bypass passage16and the warm air blown from the heater core15also flow toward both suction ports of the scroll case24b. The cooled air and the warm air collide with each other at an angle of about 90 degrees before being sucked into the suction ports.

In this way, the cooled air and warm air colliding with each other before being sucked into the scroll cases24aand24bin this way are sucked thereinto by the operations of the impellers22and23to be blown out in the radial direction. Thus, the mixture of the colliding cooled air and warm air is blown out as a conditioned air in the radial direction.

Thereafter, the conditioned air is blown out to the air passage40through the scroll cases24aand24b. The blown conditioned air passes through the air passage40and then are blown to the vehicle interior via any one of the air outlets36and37and the foot openings39and41.

Now, the characteristic structure, operations, and effects of this embodiment will be described with reference toFIGS. 3 to 5.FIG. 3is a front view of an air mix door60ofFIG. 1as seen from the windward side.FIG. 4is a cross-sectional view taken along the line IV-IV ofFIG. 3, while showing the shape of the air mix door60assembled to the guide grooves53(stuck in the guide grooves53).FIG. 5is a cross-sectional view taken along the line V-V ofFIG. 3, while showing the shape of the air mix door60assembled to the guide grooves53(stuck in the guide grooves53).

In the air mix door60of this embodiment, the radius of curvature of the plate-like portion61in a state before being assembled to the guide groove53(that is, in a single non-mounted state) is set more than the radius of curvature of each of the windward sidewall portion53aand the leeward sidewall portion53bof the guide groove53.

As shown inFIGS. 3 to 5, the one rib63extends from one end to the other end of the plate-like portion61in the door width direction (in the left-right direction of the page ofFIG. 3), and is disposed at the center portion of the plate-like portion61in the door movement direction (in the up-down direction of the page ofFIG. 3). The rib63is integrally formed with the plate-like portion61, and protrudes from the plate-like portion61toward the windward side, so that the rib63has a trapezoidal sectional shape. A part of the rack62alocated in the center portion of the plate-like portion in the door movement direction is formed at a part of the rib63, and also serves as the rib63.

As shown inFIG. 4, when assembling the air mix door60in the guide grooves53, the plate-like portion61has both end portions thereof in the door width direction supported in the following manner. The rib63is abutted against the windward sidewall portion53aat the abutment point P1, while both end portions of the plate-like portion61in the door movement direction are abutted against the leeward sidewall portions53bat abutment points P2and P3, so that the air mix door60is elastically and deformed.

An elastic restoring force that intends to return the plate-like portion61to a free state is generated at the respective abutment points P1to P3. Thus, the elastic restoring force allows both end portions in the door width direction of the plate-like portion61to be pressed against the windward sidewall portion53aand the leeward sidewall portion53b.

In this way, the plate-like portion61has both end portions thereof in the door width direction, each being supported at three points. This arrangement can suppress abnormal sounds (beat noise) from occurring due to vibration of both end portions and vicinity of the plate-like portion61in the door width direction when the entire interior air conditioning unit10vibrates while the air pressure is not applied to the plate-like portion61.

The force generated from both end portions in the door width direction of the plate-like portion61is transferred to the center portion of the plate-like portion61in the door width direction via the ribs63, so that it prevents the center portion and vicinity of the plate-like portion61from being deformed in the direction away from the seal surface of the air conditioning case11. As a result, as shown inFIG. 5, a center portion of the plate-like portion61in the door width direction is elastically bent and deformed, like both end portions in the door width direction of the plate-like portion61supported at three points, so that the center and vicinity of the plate-like portion61is pressed against the seal surface of the air conditioning case11.

In this way, because the center and vicinity of the plate-like portion61is pressed against the seal surface of the air conditioning case11, it can suppress the abnormal sounds (beat noise) from occurring due to vibration of the center and vicinity of the plate-like portion61when the entire interior air conditioning unit10vibrates when the air pressure is not applied to the plate-like portion61.

A second embodiment of the present disclosure will be described below.

This embodiment differs from the first embodiment in structure of the air mix door60. In other points, this embodiment is the same as the first embodiment, and thus only different parts of this embodiment will be described below.

As shown inFIG. 6, the air mix door60of this embodiment includes a plurality of ribs63spaced apart from each other in the door movement direction. Specifically, the ribs63are disposed at the center portion of the plate-like portion in the door movement direction and in the vicinity of both end portions thereof in the door movement direction.

With this arrangement, the force generated from both end portions of the plate-like portion61in the door movement direction is also transferred via the ribs63to the vicinity of both end portions of the plate-like portion61in the door movement direction and the center portion of the plate-like portion61in the door width direction. As a result, the center and vicinity of the plate-like portion61can be ensured to be pressed against the seal surface of the air conditioning case11, surely suppressing the abnormal sound (beat noise) from occurring due to vibration of the center and vicinity of the plate-like portion61.

A third embodiment of the present disclosure will be described below.

This embodiment differs from the first embodiment in structure of the air mix door60. In other points, this embodiment is the same as the first embodiment, and thus only different parts of this embodiment will be described below.

As shown inFIG. 7, the air mix door60of this embodiment includes a rib63whose size changes depending on the position in the door width direction. Specifically, both end parts of the rib63in the door width direction are larger than the center portion of the rib63in the door width direction.

This embodiment can be combined with the respective embodiments described above.

Although the rib63has a trapezoidal sectional shape in the respective above-mentioned embodiments, the rib63may have any other sectional shape (for example, rectangular).

In the first embodiment, the center (P1) of the plate-like portion61in the door movement direction is abutted against the windward sidewall portion53a, and the end portions (P2, P3) in the door movement direction of the plate-like portion61are abutted against the leeward sidewall portion53b, thereby causing the plate-like portion61to be elastically deformed.

However, the center (P1) of the plate-like portion61in the door movement direction may be abutted against the leeward sidewall portion53b, and the end portions (P2, P3) in the door movement direction of the plate-like portion61may be abutted against the leeward sidewall portion53a, thereby causing the plate-like portion61to be elastically deformed.