JP7187285B2 - vehicle air conditioner - Google Patents

Description

The present invention relates to a vehicle air conditioner that is mounted on a vehicle and blows air temperature-controlled by a heat exchanger into the vehicle interior to adjust the temperature of the vehicle interior.

2. Description of the Related Art Conventionally, a vehicle air conditioner mounted on a vehicle includes a blower unit for taking in outside air or inside air and blowing the air with a blower, as disclosed in Patent Document 1. In this blower unit, a blower is arranged in the center of a spiral scroll case, and the blower comprises a motor and an impeller connected to the motor to rotate. It is arranged to face the

In addition, the scroll case has a suction port that is on the axis of the blower and takes in air. A bell mouth that constitutes the suction port is formed as a continuous wall surface with the side wall.

Further, the bell mouth has a wall surface with an arcuate cross-section extending radially outward from the inlet, and the radius of curvature of the wall is adjusted to correspond to the increase in the axial height of the side wall at the inlet. By increasing the size proportionally, noise is reduced by suppressing interference of air flow in the vicinity of the bell mouth.

On the other hand, in the vehicle air conditioner disclosed in Patent Document 2, a cover member is provided on the upper part of the blower case in which the blower is housed, and the cover member is formed with a plurality of struts projecting upward to form a filter. It is configured to hold the lower surface.

JP 2007-127089 A JP 2012-158218 A

For example, when the structure of the blower unit in Patent Document 1 described above is applied to the vehicle air conditioner of Patent Document 2 in which a filter is arranged above the blower, the air outlet of the scroll case that discharges the air to the outside gradually approaches toward the side of the filter placed above. Therefore, the close proximity of the air outlet and the filter disturbs the flow of air and causes noise.

In addition, since the axial distance between the bell mouth and the axial tip of the impeller is increased, the air in the passage tends to flow back toward the fan through the gap between the two, resulting in a decrease in air blowing efficiency. Noise will increase.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and is an air conditioner for a vehicle that is capable of stabilizing the flow of sucked air, reducing noise during operation, and improving blowing efficiency. intended to provide

In order to achieve the above object, an aspect of the present invention includes a casing, a blower provided in the casing for taking in air, and a filter facing the upstream side of the blower and through which the air passes, wherein the blower is energized. A vehicle air conditioner comprising a fan that rotates under operation and a scroll case having a passage that is provided radially outside the fan and whose cross-sectional area gradually increases from the nose portion toward the rotation direction of the fan,
The scroll case has an intake port with a circular cross section that opens on one side in the axial direction of the fan, a discharge port that is connected to the downstream side of the passage and opens on the side of the scroll case, and is provided at the outer edge of the intake port. a bell mouth formed with a tip protruding toward the filter side from the wall surface of the scroll case where the mouth is formed,
The bellmouth has a point A at the intersection of a first imaginary line connecting the nose of the scroll case and the axial center of the fan, and a second imaginary line connecting the winding end of the scroll case and the axial center of the fan. When the intersection point is point B, and an arbitrary intermediate point between points A and B in the direction of rotation of the fan is point C, the distance from the bell mouth to the filter along the axial direction of the fan is point A and It is formed so as to protrude so that the point C is smaller than the point B ,
The scroll case expands in the axial direction of the fan so that the passage is provided radially outward of the fan, and the wall surface on the side where the suction port is formed gradually approaches the filter side from the nose portion toward the rotational direction of the fan. death,
The bell mouth at point B is formed away from the filter with respect to the wall surface of the scroll case near point B on which the suction port is formed .

According to the present invention, a blower constituting a vehicle air conditioner includes a scroll case having a passage whose cross-sectional area gradually increases from the nose portion toward the rotation direction of the fan. A bell mouth is formed on the outer edge of the suction port that opens on one side in the axial direction, and protrudes from the wall surface of the scroll case toward the filter.

The bellmouth has point A at the intersection of the first imaginary line connecting the nose of the scroll case and the center of the shaft of the fan, and the second imaginary line connecting the winding end of the scroll case and the center of the fan shaft. and point B is an arbitrary intermediate point between point A and point B in the direction of rotation of the fan. The C point is set to be smaller than the point and the B point.

Therefore, in the passage of the scroll case, in the vicinity of the point A adjacent to the nose portion where the air pressure is high, by narrowing the axial distance between the upper end of the fan and the bell mouth, the air flows backward. By forming the bell mouth so that the distance to the filter side becomes smaller in the vicinity of point C as the winding angle of the passage increases, the air that has passed through the filter is preferably directed to the intake port. Since it can be guided, the air flow can be made uniform.

In addition, in the vicinity of point B, which is the vicinity of the discharge port, the height of the passage in the axial direction of the fan increases and the filter is approached. can be done.

As a result, the backflow of air near the nose of the blower is prevented, and the flow of air from the filter to the suction port is guided and made uniform, thereby stabilizing the air flow and increasing the blowing efficiency. , it is possible to reduce noise during rotation of the fan.

According to the present invention, the following effects are obtained.

That is, in the scroll case of the blower that constitutes the vehicle air conditioner, the distance of the bellmouth to the filter is the intersection of the first imaginary line connecting the nose of the scroll case and the shaft center of the fan; Let C be an arbitrary intermediate point between points A and B in the rotation direction of the fan with respect to point B, which is the intersection of the second imaginary line connecting the winding end of the scroll case and the shaft center of the fan. It is better to set so that the point is smaller.

As a result, in the vicinity of point A, which is adjacent to the nose section where the air pressure is high, the fan and the bellmouth are placed close to each other, so that the backflow of air can be prevented and the winding angle of the passage from point A increases. By arranging the bell mouth close to the filter side in the vicinity of the point C, the air from the filter can be preferably guided to the suction port and the air flow can be made uniform. Also, in the vicinity of the point B, which is in the vicinity of the ejection port, it is possible to secure a sufficient distance between the bell mouth and the filter.

As a result, the backflow of air near the nose of the blower can be prevented, and the flow of air can be made uniform by guiding it from the filter to the suction port. It is possible to reduce noise when the fan rotates.

1 is a partially omitted cross-sectional view of an inside/outside air switching unit that constitutes a vehicle air conditioner according to an embodiment of the present invention; FIG. FIG. 2 is a top plan view of the scroll case and the fan of the blower unit shown in FIG. 1 ; FIG. 3 is a cross-sectional view taken along line III-III of FIG. 2; FIG. 4A is a schematic diagram of height change along the circumferential direction of the bell mouth, and FIG. 4B is a schematic diagram of height change of the bell mouth of the blower unit according to the modification.

Preferred embodiments of a vehicle air conditioner according to the present invention will be described in detail below with reference to the accompanying drawings. In FIG. 1, reference numeral 10 indicates a vehicle air conditioner according to an embodiment of the present invention.

This vehicle air conditioner 10, as shown in FIG. 1, has an inside/outside air switching unit 12 connected to the side of an air conditioning case (not shown) constituting each air passage and taking in outside air and inside air. The air taken in from the inside/outside air switching unit 12 is supplied to the air conditioning case.

1 and 2, the inside/outside air switching unit 12 includes a blower unit 14, a casing 16 connected to the upper part of the blower unit 14 and having a switching damper (not shown), and a and a filter 18 provided to face the blower unit 14 . The casing 16 has an inlet 20 (see FIG. 1) for introducing outside air and inside air.

The filter 18 is provided under the casing 16 to which the blower unit 14 is connected, and is arranged horizontally (in the direction of arrow A) so as to be substantially orthogonal to the height direction of the casing 16 .

The blower unit 14 includes, for example, a drive motor 22, a fan 24 that rotates under the driving action of the drive motor 22, and a scroll case 28 that houses the drive motor 22 and the fan 24 and has a passage portion 26 through which air flows. including.

The drive motor 22 is provided, for example, at a substantially central lower portion of the scroll case 28, and is fixed so that its rotating shaft 30 protrudes upward (in the direction of arrow B1) within the scroll case 28. As shown in FIG. The rotating shaft 30 is connected to the center of the fan 24 and rotates integrally with the driving motor 22 when the driving motor 22 is energized.

The fan 24 is housed substantially in the center of the scroll case 28, and includes a plurality of blades 32 spaced equally apart in the circumferential direction, an annular shroud 34 provided at the upper end of the blades 32, and the lower ends of the blades 32. and a boss portion 36 extending from the portion toward the center toward the upper end side. A boss portion 36 of the fan 24 is inclined from its center toward the outer periphery and downward (in the direction of arrow B2), and the center is connected to the rotation shaft 30 of the drive motor 22 .

The scroll case 28 includes, for example, a case body 38 that is formed substantially in the center and houses the fan 24 , and a holder 40 that is provided substantially in the lower part of the center of the case body 38 and houses the drive motor 22 .

A passage portion 26 is formed in the case body 38 so as to surround the outer peripheral side of the fan 24 that is housed therein. It is formed so as to be vertically divisible (in the directions of arrows B1 and B2) from the lower case 44 connected in the direction of B2).

The passage portion 26 is formed so as to straddle the upper case 42 and the lower case 44, and as shown in FIG. A spiral passage 46 formed in a spiral while expanding radially outward and in the axial direction of the fan 24 (directions of arrows B1 and B2), and a straight line from the winding end C2 of the spiral passage 46 in the tangential direction. and a discharge passageway 48 extending through. A discharge port 50 opens at the downstream end of the discharge passage 48, and the discharge port 50 is connected to an air conditioning case via a connecting duct (not shown).

Further, the passage portion 26 is formed with a nose portion 52 that joins the winding start C<b>1 of the spiral passage 46 and the inner peripheral wall of the discharge passage 48 . That is, the passage portion 26 is formed so that the cross-sectional area gradually increases from the nose portion 52 at the winding start C1 toward the winding end C2.

As shown in FIGS. 1 and 3, the upper case 42 has an upper wall (wall surface) 54 with an inlet 56 opening at the center thereof. 16 and the filter 18, and the inside of the scroll case 28 and the inside of the casing 16 are communicated with each other.

Further, the upper case 42 is formed with a bell mouth 58 that is bent inwardly in an arcuate cross-section on the outer peripheral edge of the suction port 56 . The bell mouth 58 is formed in an annular shape along the suction port 56 and connected to the upper wall 54 of the upper case 42 so that the height in the upward direction along the axial direction (in the direction of arrow B1) differs in the circumferential direction. is formed in

Specifically, when viewed from the axial direction of the scroll case 28 (the directions of arrows B1 and B2 in FIG. 1), the nose portion 52 and the axial center P of the fan 24 (the center of the rotating shaft 30) shown in FIG. ) and the bell mouth 58 is a point Pa (point A), and a second virtual line D2 connecting the winding end C2 of the spiral passage 46 and the shaft center P and the bell mouth 58 point Pb (point B), and an arbitrary intermediate point between the point Pa and the point Pb in the rotation direction of the fan 24 is a point Pc (point C). A predetermined range of the bell mouth 58 becomes a protruding ring portion 64 which is formed higher than the first ring portion 60 which is the point Pa and the second ring portion 62 which is centered at the point Pb.

Also, the first and second ring portions 60 and 62 are formed to have substantially the same height in the axial direction of the blower unit 14 (directions of arrows B1 and B2).

Furthermore, the above-mentioned point Pc is set, for example, within an angle θ of 30° to 210° toward the winding end C2 side with respect to the first virtual line D1 passing through the point Pa.

As shown in FIGS. 1 to 4A, the protruding ring portion 64 is formed with a predetermined length along the circumferential direction of the bell mouth 58 so as to fall within the range of the angle θ, and is formed with a substantially constant height. a first gradually changing portion 68 whose height gradually changes so as to protrude upward (arrow B1 direction) from the first ring portion 60 toward the top portion 66; and a second gradually changing portion 70 whose height gradually changes downward (arrow B2 direction) toward the second ring portion 62 side. That is, the protruding ring portion 64 is formed in a substantially trapezoidal cross section from the top portion 66 and the first and second gradually changing portions 68 and 70 (see FIG. 4A).

As shown in FIG. 4A, the distance L from the bell mouth 58 to the filter 18 along the axial direction of the fan 24 (directions of arrows B1 and B2) is the first ring portion 60 including the point Pa and the second ring portion including the point Pb. The bell mouth 58 is formed to protrude upward (in the direction of arrow B1) so that the protruding ring portion 64 including the point Pc is shorter than the second ring portion 62 .

In other words, the bell mouth 58 is provided with the protruding ring portion 64 closer to the filter 18 side than the first and second ring portions 60 , 62 .

The vehicle air conditioner 10 according to the embodiment of the present invention is basically configured as described above, and the operation and effects thereof will now be described.

First, the drive motor 22 of the inside/outside air switching unit 12 is driven based on a control signal from a controller (not shown). Air is sucked into the casing 16 from the inlet 20 of the air.

After passing through the filter 18, the air taken into the casing 16 is sucked inside the fan 24 through the shroud 34 from the suction port 56 of the scroll case 28 in the blower unit 14, and along the boss portion 36 downward ( arrow B2 direction) and to the outer peripheral side, and then delivered to the outer peripheral side through between the blades 32 .

The air sent to the passage portion 26 flows counterclockwise along the spiral passage 46 from the winding start C1 to reach the winding end C2 side, and then flows from the discharge passage 48 to the discharge port 50 to provide air conditioning (not shown). sent to the case side.

In addition, the air flowing through the passage portion 26 described above gradually increases in pressure as it swirls from the winding start C1 of the spiral passage 46 to the discharge passage 48, and part of the air flows into the nose portion 52. From the discharge passage 48 having a high pressure in the vicinity, it may flow into the winding start C1 side of the adjacent spiral passage 46 having a low pressure.

Therefore, in the scroll case 28, the distance between the first ring portion 60 of the bell mouth 58 and the upper end 24a along the axial direction of the fan 24 should be narrowed near the point Pa near the nose portion 52 where the pressure is high. This prevents the radially inward reverse flow of air through between the bell mouth 58 and the fan 24 .

Furthermore, in the vicinity of the point Pc where the winding angle of the spiral passage 46 becomes large in the scroll case 28, the protruding ring portion 64 is provided so that the bell mouth 58 protrudes upward (in the direction of arrow B1) and approaches the filter 18. As a result, the air that has passed through the filter 18 is led to the suction port 56 side.

Air sent from the blower unit 14 of the inside/outside air switching unit 12 to an air-conditioning case (not shown) is adjusted to a desired temperature in the air-conditioning case, and then flows into the passenger compartment through the blower port. and is blown.

As described above, in the present embodiment, in the blower unit 14 of the inside/outside air switching unit 12 constituting the vehicle air conditioner 10, the bell mouth 58 of the scroll case 28 is axially (arrow B1 direction), and the height of the protrusion is a point Pa, which is the intersection of a first imaginary line D1 connecting the nose portion 52 of the scroll case 28 and the center of the shaft of the fan 24, and the winding end of the scroll case 28. A point Pb, which is an intersection of a second virtual line D2 connecting C2 and the shaft center of the fan 24, and an arbitrary intermediate point between the points Pa and Pb in the rotation direction of the fan 24, is a point Pc. , the distance L from the bell mouth 58 to the filter 18 along the axial direction of the fan 24 (directions of arrows B1 and B2) is shorter at the point Pc than at the points Pa and Pb. is set to be

Therefore, in the passage portion 26 of the scroll case 28, in the vicinity of the nose portion 52 where the air pressure is high, which is the vicinity of the point Pa, the upper end 24a along the axial direction of the fan 24 and the first ring portion 60 of the bell mouth 58 By reducing the distance along the axial direction between them, it is possible to prevent the backflow of the air through between them.

In addition, by providing the bell mouth 58 with a protruding ring portion 64 that protrudes upward as the winding angle increases from the winding start C1 of the passage portion 26, the air passing through the filter 18 and taken into the suction port 56 is reduced. The flow can be homogenized by suitable guidance.

Furthermore, since the height of the passage portion 26 increases as the bell mouth 58 approaches the discharge port 50 in the vicinity of the point Pb, the height of the bell mouth 58 is lower than the projecting ring portion 64 so as to secure the axial distance L from the filter 18 . 2 ring portion 62 is provided. Therefore, even in the vicinity of the discharge port 50, by ensuring a sufficient distance L between the bell mouth 58 and the filter 18, noise generation can be suppressed.

As a result, the backflow of air toward the fan 24 side near the nose portion 52 of the blower unit 14 is prevented, and the air flow is guided from the filter 18 to the suction port 56 to make it uniform. It is possible to reduce noise when the fan 24 rotates, while stabilizing the flow and increasing the air blowing efficiency.

Further, the second ring portion 62 of the bell mouth 58 is formed near the second ring portion 62 so as to face the fan 24 side (arrow B2 direction) with respect to the upper wall 54 of the scroll case 28 having the intake port 56 open. By doing so, the second ring portion 62 can be arranged sufficiently away from the filter 18 .

As a result, in the scroll case 28, the bell mouth 58 is spaced apart from the filter 18 in the vicinity of the discharge port 50, which expands axially upward (in the direction of the arrow B1) and the distance from the filter 18 becomes small, thereby reducing noise. Occurrence can be reduced more effectively.

Furthermore, in the bell mouth 58, by setting the point Pc within an angle θ of 30° to 210° with respect to the first virtual line D1 passing through the point Pa (30° ≤ θ ≤ 210°), the vicinity of the nose portion 52 It is possible to achieve both the prevention of the backflow of air and the noise reduction at the intermediate portion between the winding start C1 and the winding end C2 and the discharge port 50 in a well-balanced manner.

On the other hand, the projecting ring portion 64 of the bell mouth 58 has a first gradually changing portion 68 whose height smoothly increases from the first ring portion 60 side toward the top portion 66 and a height which smoothly decreases from the top portion 66 . It is not limited to the configuration including the second gradually changing section 70 .

For example, like the bell mouth 80 shown in FIG. 4B, a first top portion 84 formed stepwise with respect to the first ring portion 82 and a second top portion 86 connected to the first top portion 84 and slightly lower. , and a second ring portion 88 which is stepped lower than the second top portion 86 may be formed to form a stepped shape.

In this case, the first and second apexes 84, 86 may be set, for example, within a range of 30° to 210° toward the winding end C2 with respect to the first imaginary line D1 passing through the point Pa. . Also, the number of stepped apexes may be appropriately set.

It should be noted that the vehicle air conditioner according to the present invention is not limited to the above-described embodiment, and it goes without saying that various configurations can be adopted without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10... Vehicle air conditioner 12... Inside/outside air switching unit 14... Blower unit 18... Filter 24... Fan 26... Passage part 28... Scroll case 30... Rotating shaft 42... Upper case 52... Nose part 56... Suction port 58, 80... Bell mouth 64... Protruding ring part 66... Top part 84... First top part 86... Second top part

Claims (4)

a fan provided in the casing for taking in air; and a filter facing the upstream side of the fan through which the air passes, wherein the fan rotates under energization; A vehicular air conditioner comprising a scroll case provided radially outwardly and having a passage whose cross-sectional area gradually increases from the nose portion toward the rotation direction of the fan,
The scroll case includes an intake port with a circular cross section that opens to one axial side of the fan, a discharge port that is connected to the downstream side of the passage and opens to the side of the scroll case, and an outer edge portion of the intake port. a bell mouth provided with a tip protruding toward the filter from a wall surface of the scroll case where the suction port is formed;
The bellmouth has a point A at the intersection of a first imaginary line connecting the nose portion of the scroll case and the axial center of the fan, and a point A connecting the winding end portion of the scroll case and the axial center of the fan. The bell mouth along the axial direction of the fan, where point B is the point of intersection with two virtual lines, and point C is an arbitrary intermediate point between point A and point B in the rotation direction of the fan. The distance from to the filter is projected so that the point C is smaller than the point A and the point B ,
The scroll case is arranged such that the passage is provided outside the fan in the radial direction, and the wall surface on the side where the suction port is formed gradually approaches the filter side from the nose portion toward the rotation direction of the fan. expands in the axial direction of the fan,
The vehicle air conditioner, wherein the bell mouth at the point B is formed away from the filter with respect to the wall surface of the scroll case near the point B on which the suction port is formed. In the vehicle air conditioner according to claim 1 ,
The vehicle air conditioner, wherein the height of the bell mouth smoothly changes from the point C to the points A and B. In the vehicle air conditioner according to claim 1 ,
The vehicle air conditioner, wherein the height of the bell mouth changes stepwise from the point C toward the points A and B. In the vehicle air conditioner according to any one of claims 1 to 3 ,
The vehicle air conditioner, wherein the point C is set within a range of 30° to 210° from the point A toward the winding end of the scroll case.

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