JP6862290B2 - Centrifugal blower for vehicle air conditioners - Google Patents

Description

The present invention relates to a centrifugal blower applied to a two-layer flow type vehicle air conditioner.

In the field of vehicle air conditioners, two-layer flow type vehicle air conditioners are known. This type of air conditioner includes two air passages separated from each other, that is, a first air passage and a second air passage, and a single centrifugal blower that blows air through these two air passages. The centrifugal blower has a suction port of the scroll housing and a separation cylinder inserted in the radial inner space of the impeller blade row. The space on the outer periphery of the scroll housing is divided into upper and lower parts by a separation wall, whereby a first air flow path communicating with the first air passage and a second air flow path communicating with the second air passage are formed. In the separation cylinder, the air flowing outside the separation cylinder is introduced into the upper half of the blade row and then flows into the first air flow path, and the air flowing inside the separation cylinder is introduced into the lower half of the blade row. After that, it is provided so as to flow into the second air flow path.

Patent Document 1 describes a centrifugal blower in which the axial position of the tip of the separation cylinder is shifted to the suction port side from the axial position of the tip of the partition wall. According to Patent Document 1, the above configuration prevents air flowing outside the separation cylinder from flowing into the second air flow path, and sets the flow rate ratio of the air flowing through the first air flow path and the second air flow path to 1: 1. It is stated that it can be 1.

However, in the configuration of Patent Document 1, when the rotation speed of the impeller is slow and the flow velocity of the air flow outside the separation cylinder is slow, the air flow inside the separation cylinder may flow into the first air flow path. .. That is, in this case, the air flow rate ratio flowing into the first air flow path and the second air flow path deviates from the target 1: 1.

The main purpose of adopting the two-layer flow system is to blow out low-humidity air flowing through the first air flow path, that is, outside air to the front window to ensure window clearness, and at the same time, air with high temperature and humidity in the second air flow path. In other words, it is to circulate the inside air and secure the heating performance with less energy. It is contrary to the above purpose that the high humidity air flowing inside the separation cylinder flows into the first air flow path.

Japanese Unexamined Patent Publication No. 2004-132342

The present invention can prevent the air flowing inside the separation cylinder from flowing into the first air flow path as much as possible, and can prevent the air flowing outside the separation cylinder from flowing into the second air flow path. It is an object of the present invention to provide a centrifugal blower that can prevent as much as possible.

According to one embodiment of the present invention, it is a single-suction type centrifugal blower for a vehicle, which has a motor and a plurality of blades forming a blade row arranged in the circumferential direction, and is rotated around a rotation axis by the motor. An impeller that is rotationally driven and blows out air sucked into the space inside the radial direction of the blade row from one end side in the axial direction toward the outside in the radial direction, an internal space that accommodates the impeller, and the axial direction. A scroll housing having a suction port that opens on one end side and a discharge port that opens in the circumferential direction, and an inner peripheral surface of the scroll housing and an outer peripheral surface of the impeller in the internal space of the scroll housing. The area between them and the internal space of the discharge port are divided in the axial direction to form a first air flow path and a second air flow path, and the blade row passes through the inside in the radial direction of the suction port. It is a separation cylinder extending in the axial direction to the inside in the radial direction of the above, and the flow of air sucked into the scroll housing from the suction port is the first air flow passing through the outside of the separation cylinder and the separation cylinder. The separation cylinder includes a separation cylinder that is divided into a second air flow passing through the inside, and the separation cylinder has a first guide portion and a second guide portion located radially inside the blade row, and the first guide portion is provided. The 1 guide portion and the second guide portion are composed of different portions of the separation cylinder, and the first guide portion has a first turning surface for turning the first air flow outward in the radial direction. The second guide portion is provided with a centrifugal blower having a second turning surface that turns the second air flow outward in the radial direction.

According to the embodiment of the present invention, since the first guide portion and the second guide portion are composed of different parts of the separation cylinder, the shape and arrangement of the first turning surface and the shape of the second turning surface And the arrangement can be set independently. Therefore, the air flowing inside the separation cylinder is prevented from flowing into the first air flow path as much as possible, and the air flowing outside the separation cylinder is prevented from flowing into the second air flow path as much as possible. Designs that can be prevented are facilitated.

It is a vertical cross-sectional view which shows the structure in the vicinity of the air intake part of an air conditioner and a centrifugal blower, and includes the meridional cross section of a centrifugal blower. FIG. 3 is a vertical cross-sectional view showing a structure in the vicinity of an air intake portion of an air conditioner and a centrifugal blower cut at a cut surface orthogonal to the cut surface in FIG. It is a meridional cross-sectional view which shows the main part of the centrifugal blower which concerns on 1st Embodiment. It is a meridional cross-sectional view which shows the main part of the centrifugal blower which concerns on 2nd Embodiment. It is a meridional cross-sectional view which shows the main part of the centrifugal blower which concerns on 3rd Embodiment. It is a meridional cross-sectional view which shows the main part of the centrifugal blower which concerns on 4th Embodiment. It is a meridional cross-sectional view which shows the main part of the centrifugal blower which concerns on the modification of 4th Embodiment. It is a meridional cross-sectional view which shows the main part of the centrifugal blower which concerns on 5th Embodiment. It is sectional drawing of the main part of the centrifugal blower cut along the line IX-IX in FIG. It is sectional drawing of the separation cylinder which shows the area X in FIG. 9 enlarged. It is a meridional cross-sectional view of the centrifugal blower cut along the line XI-XI in FIG.

An embodiment of the present invention will be described below with reference to the accompanying drawings.

1 and 2 are cross-sectional views showing a structure in the vicinity of an air intake portion of an air conditioner for a vehicle and a centrifugal blower.

The centrifugal blower 1 is a single-suction type centrifugal blower. The centrifugal blower 1 has an impeller 2. The impeller 2 has a plurality of blades 3 forming a blade row 3A arranged in the circumferential direction on the outer peripheral portion thereof. The impeller 2 is rotationally driven around the rotation axis Ax by the motor 13, and the air sucked from the upper side in the axial direction (one end side in the axial direction) into the space inside the radial direction of the blade row of the impeller 2 is directed outward in the radial direction. And blow out.

In the present specification, for convenience of explanation, the direction of the rotation axis Ax is referred to as an axial direction or a vertical direction, and the upper and lower sides of FIGS. 1 and 2 are referred to as "axial upper side" and "axial lower side", respectively. Call. However, this does not mean that the direction of the rotation axis Ax coincides with the vertical direction when the air conditioner is actually incorporated in the vehicle. Further, in the present specification, unless otherwise specified, the direction of the radius of a circle drawn on a plane orthogonal to the rotation axis Ax with an arbitrary point on the rotation axis Ax as the center is referred to as a radial direction. The circumferential direction of the circle is called the circumferential direction or the circumferential direction.

The impeller 2 includes an inner deflection member 9 integrally molded with the impeller 2. The inner deflection member 9 is sometimes called a cone portion. The inner deflection member 9 is a rotating body in a geometrical sense, and has a side peripheral portion 10 and a disk-shaped central portion 11. At the central portion 11, the rotating shaft 12 of the motor 13 is connected to the impeller 2. In this example, the side peripheral portion 10 is curved so that the contour line in the meridional cross section of the outer peripheral surface of the side peripheral portion 10 becomes steeper as it approaches the central portion 11. In another example (not shown), in the case where the contour line in the meridional cross section of the outer peripheral surface of the side peripheral portion 10 is not curved from the central portion 11 toward the blade row 3A (the cross section is linear). There is also.

The impeller 2 is housed in a substantially cylindrical internal space of the scroll housing 17. The scroll housing 17 has a suction port 22 that opens upward in the axial direction and a discharge port 170. When the scroll housing 17 is viewed from the axial direction, the discharge port 170 extends substantially in the tangential direction of the outer peripheral surface of the scroll housing 17. The discharge port 170 is not visible in FIG.

The scroll housing 17 has a partition wall 20 extending inward in the radial direction from the outer peripheral wall 17A of the scroll housing 17. The partition wall 20 divides the area between the inner peripheral surface of the scroll housing 17 and the outer peripheral surface of the impeller 2 in the internal space of the scroll housing 17 in the axial direction (up and down), and divides the area of the scroll housing 17 vertically. The upper first air flow path 18 and the lower second air flow path 19 extending in the circumferential direction along the outer peripheral wall 17A are formed.

A separation cylinder 14 is inserted into the scroll housing 17 via a suction port 22. The separation cylinder 14 is a rotating body in a geometrical sense except for the upper part in the axial direction. As can be understood by comparing and contrasting FIGS. 1 and 2, the cross section of the upper portion of the separation cylinder 14 is generally rectangular. The cross section of the central portion 15 of the separation cylinder 14 is circular. The cross-sectional shape of the separation cylinder 14 smoothly changes from a rectangle to a circle as it approaches the central portion 15 from the upper part. The lower portion 16 of the separation cylinder 14 has a flare shape that increases in diameter as it approaches the lower end.

The separation cylinder 14 passes through the space inside the suction port 22 in the radial direction and extends axially to the space 4 inside the blade row 3A of the impeller 2 in the radial direction. The upper end opening of the separation cylinder 14 is located on the outside of the scroll housing 17 (axially above the suction port 22). The lower end of the separation cylinder 14 is located in the space 4 inside the blade row 3A of the impeller 2 in the radial direction.

The entire separation cylinder 14 may be integrally molded by resin injection molding. Instead of this, the upper portion of the separation cylinder 14 and the central portion and the lower portion of the separation cylinder 14 may be separately molded and then connected to each other.

The separation cylinder 14 allows the air flow sucked into the scroll housing 17 to pass through the first air flow 14A outside the separation cylinder 14 and the second passage 14B inside the separation cylinder 14. Divide into airflow. The first air flow passes through a ring-shaped region outside the outer peripheral surface of the separation cylinder 14 of the suction ports 22 of the scroll housing 17, and the upper half portion 5 of the blade row of the impeller 2 (the portion close to the suction port 22). Inflow to. The second air flow enters the inside of the separation cylinder 14 from the upper end of the separation cylinder 14 and flows into the lower half portion 6 (the portion far from the suction port 22) of the blade row of the impeller 2. Therefore, the ring-shaped region outside the outer peripheral surface of the separation cylinder 14 of the suction ports 22 of the scroll housing 17 is the first suction port of the scroll housing 17, and the upper end opening of the separation cylinder 14 is the second suction port of the scroll housing 17. Can also be regarded as.

The air intake portion of the air conditioner has a housing 21. The housing 21 will be referred to as an "air intake housing" to distinguish it from the scroll housing 17. The scroll housing 17 and the air intake housing 21 may be integrally molded, or may be manufactured separately and then connected by a method such as screwing, bonding, or fitting. The scroll housing 17 and the air intake housing 21 form a part of the air conditioner casing. In one preferred embodiment, the separation cylinder 14 is a separate component from the scroll housing 17 and the air intake housing 21, and is supported at a predetermined position by the air intake housing 21.

The air intake housing 21 has a first opening 25, a second opening 26, a third opening 27, and a fourth opening 28. Inside air (in-vehicle air) from the exit 29 (details not shown) of the inside air introduction path provided in the vehicle into the internal space 23 of the air intake housing 21 through the first opening 25 and the third opening 27. Can be introduced. Further, through the second opening 26 and the fourth opening 28, the outside air (outside the vehicle) is introduced into the internal space 23 of the air intake housing 21 from the outlet 30 (details are not shown) of the outside air introduction path provided in the vehicle. Air taken in from) can be introduced.

By rotating the shutoff valve 31 around the rotation shaft 31A, the inflow of air (inside air) from the first opening 25 into the air intake housing 21 can be allowed or shut off. By rotating the shutoff valve 32 around the rotation shaft 32A, the inflow of air (outside air) from the second opening 26 into the air intake housing 21 can be allowed or shut off. By rotating the switching valve 33 around the rotation shaft 33A to switch the position, air (inside air or outside air) is introduced into the air intake housing 21 via either the third opening 27 or the fourth opening 28. It can be inflowed.

Almost all of the air introduced into the air intake housing 21 from the first opening 25 and / or the second opening 26 passes through the second passage 14B, and from the third opening 27 and / or the fourth opening 28. The air intake housing 21 and the separation cylinder 14 are formed so that almost all of the air introduced into the air intake housing 21 passes through the first passage 14A.

Between the area where the first opening 25, the second opening 26, the third opening 27 and the fourth opening 28 are arranged and the upper end of the separation cylinder 14, the air intake housing 21 contains dust and particles in the air. A filter 35 for removing pollutants such as the above is provided. The filter 35 preferably consists of a single filter element.

Next, the operation of the vehicle air conditioner shown in FIGS. 1 and 2 will be described.

In the first operation mode of the vehicle air conditioner, the second opening 26 and the fourth opening 28 are opened, and the first opening 25 and the third opening 27 are closed. This state is not shown. In this case, the outside air introduced from the second opening 26 passes through the first passage 14A outside the separation cylinder 14 and forms a first air flow that flows into the upper half 5 of the blade row 3A of the impeller 2. Further, the outside air introduced from the fourth opening 28 passes through the second passage 14B inside the separation cylinder 14 and forms a second air flow that flows into the lower half 6 of the blade row of the impeller 2. The first operation mode is sometimes called the outside air mode.

In the second operation mode, the second opening 26 and the third opening 27 are opened, and the first opening 25 and the fourth opening 28 are closed. This state is shown in FIGS. 1 and 2. In this case, the outside air FE introduced from the second opening 26 passes through the first passage 14A outside the separation cylinder 14 and forms a first air flow flowing into the upper half 5 of the blade row 3A of the impeller 2. .. Further, the inside air FR introduced from the third opening 27 passes through the second passage 14B inside the separation cylinder 14 and forms a second air flow flowing into the lower half portion 6 of the blade row 3A of the impeller 2. The second operation mode is sometimes called the inside / outside air two-layer flow mode.

In the third operation mode, the first opening 25 and the third opening 27 are opened, and the second opening 26 and the fourth opening 28 are closed. This state is not shown. In this case, the inside air introduced from the first opening 25 passes through the first passage 14A outside the separation cylinder 14 and forms a first air flow that flows into the upper half 5 of the blade row 3A of the impeller 2. Further, the inside air introduced from the third opening 27 passes through the second passage 14B inside the separation cylinder 14 and forms a second air flow flowing into the lower half 6 of the blade row 3A of the impeller 2. The third operation mode is sometimes called the inside air mode.

The second operation mode (inside / outside air two-layer flow mode) is a heating operation that quickly warms the vehicle interior while preventing fogging of the front window from a cold state in the vehicle interior, especially in winter or when the temperature is relatively low. It is used when doing. When this heating operation is performed by automatic control, the outside air FE is blown from the defroster outlet (not shown) in the passenger compartment to the front window (not shown) for a while after the start of heating, and the inside air FR is blown into the passenger compartment. It is blown out from the foot outlet (not shown) toward the passenger's feet.

When the second operation mode (inside / outside air two-layer flow mode) is executed, the outside air FE flowing into the upper half 5 of the blade row 3A of the impeller 2 enters the defroster outlet via the first air flow path 18. The inside air FR that is supplied and flows into the lower half 6 of the blade row 3A of the impeller 2 is supplied to the foot outlet via the second air flow path 19. At this time, if the high-humidity inside air FR is mixed with the outside air FE supplied to the defroster outlet, an event that poses a safety problem such as fogging of the front window may occur. Further, if the low-temperature outside air FE is mixed with the inside air FR supplied to the foot outlet, it may cause discomfort to the passengers. Therefore, when the second operation mode is executed, it is desirable that all of the outside air FE flows into the first air flow path 18 and all of the inside air FR flows into the second air flow path 19.

Since only the inside air or only the outside air is used when the first and third operation modes are executed, there is no strict requirement for avoiding mixing of the inside air and the outside air as in the execution of the second operation mode.

Hereinafter, with respect to the first to fourth embodiments of the centrifugal blower 1 provided with the separation cylinder 14 capable of efficiently preventing the mixing of the inside air and the outside air, refer to FIGS. 3 to 6 which are the meridional cross sections of the centrifugal blower 1. I will explain. 3 to 6 show an enlarged configuration of the region surrounded by the alternate long and short dash line surrounded by the reference numerals "III to VI" in FIG.

As shown in FIGS. 3 to 6, the separation cylinder 14 of the centrifugal blower 1 according to the first to fourth embodiments has the following common features. The separation cylinder 14 has a first guide portion 110 and a second guide portion 120 located in the space 4 inside the blade row 3A of the impeller 2 in the radial direction. The first guide portion 110 has a first turning surface 112 that diverts the first air flow passing through the first passage 14A outward in the radial direction, and the second guide portion 120 passes the second air flow passing through the second passage 14B. It has a second turning surface 122 that turns outward in the radial direction. The outer peripheral surface of the side peripheral portion 10 of the inner deflection member 9 (cone portion) greatly contributes to the conversion of the second air flow passing through the second passage 14B, but the second conversion surface 122 is also the second air. It contributes to the conversion of the flow.

The first guide portion 110 and the second guide portion 120 are composed of different parts of the separation cylinder 14. When the front surface and the back surface of the same wall portion of the separation cylinder 14 form the first turning surface 112 and the second turning surface 122, the first guide portion 110 and the second guide portion 120 are "different from each other" of the separation cylinder 14. It is considered that it does not correspond to the feature of "consisting of parts". That is, the first guide portion 110 is the first wall portion of the separation cylinder 14 having the front surface and the back surface (one of which, in the illustrated example, the front surface is the first turning surface 112), and the second guide portion 120. Is the second wall portion of the separation cylinder 14 different from the first wall portion having the front surface and the back surface (one of which, the back surface is the second turning surface 122 in the illustrated example), which corresponds to the above feature.

As described above, since the first guide portion 110 and the second guide portion 120 are composed of different parts of the separation cylinder 14, the shapes and arrangements of the first turning surface 112 and the second turning surface 122 are optimized. Can be easily realized. On the other hand, if the first turning surface 112 and the second turning surface 122 are formed by the front surface and the back surface of the same wall portion of the separation cylinder 14, the shapes of the first turning surface 112 and the second turning surface 122 And optimization of placement is difficult.

First, a first embodiment of the separation cylinder 14 will be described with reference to FIG. As shown in FIG. 3, when viewed in the meridional cross section of the centrifugal blower 1, the tip portion of the separation cylinder 14 is bifurcated to form the first wall portion 141 and the second wall portion 142. The base end of the first wall portion 141 and the base end of the second wall portion 142 are connected, and the tip of the first wall portion 141 and the tip of the second wall portion 142 are separated.

The axial position of the tip of the first wall portion 141 is above the axial position of the tip of the second wall portion 142 (position close to the suction port 22). The first wall portion 141 constitutes the above-mentioned first guide portion 110, and the surface of the first wall portion 141 facing the first passage 14A is the first turning surface 112. Further, the second wall portion 142 constitutes the above-mentioned second guide portion 120, and the surface of the second wall portion 142 facing the second passage 14B becomes the second turning surface 122.

The axial position of the tip 114 of the first turning surface 112 of the first guide portion 110 (first wall portion 141) is the axial position of the tip 201 of the surface of the partition wall 20 facing the first air flow path 18. It is located closer to the suction port 22 (at a position higher in the axial direction). As a result, it is possible to prevent or minimize the air flowing in the first passage 14A from entering the second air passage 19 after being converted to the first turning surface 112 and separated from the first turning surface 112. Can be done. If the axial position of the tip 114 of the first turning surface 112 is the same as the axial position of the tip 201 of the surface of the partition wall 20 facing the first air flow path 18, the inside of the first passage 14A Even if the flowing air is converted to the first turning surface 112, a part of the air may not be completely converted and may enter the second air flow path 19.

The axial position of the tip 124 of the second turning surface 122 of the second guide portion 120 (second wall portion 142) is the axial position of the tip 202 of the surface of the partition wall 20 facing the second air flow path 19. It is at the same position as or farther from the suction port 22 (in the same axial position in FIG. 3). As a result, it is possible to prevent or minimize the air flowing in the second passage 14B from entering the first air passage 18 after being converted to the second turning surface 122 and separated from the second turning surface 122. Can be done. Temporarily, the axial position of the tip 124 of the second turning surface 122 is closer to the suction port 22 than the axial position of the tip 202 of the surface facing the second air passage 19 of the partition wall 20 (more shaft). (Position on the upper side in the direction), a part of the air flowing in the second passage 14B converted by the second turning surface 122 may enter the first air passage 18.

The axial position of the tip 114 may be closer to the suction port 22 than the axial position of the tip 201, while the axial position of the tip 124 may be the same as the axial position of the tip 202. The reason for not having this is that the first airflow that is turned outward in the radial direction by the first turning surface 112 and the second airflow that is turned outward in the radial direction by the second turning surface 122 are axially downward (suctioned). This is because the inertia (in the direction away from the mouth 22) acts. That is, due to this inertia, even if the positions of the tip 124 and the tip 202 in the axial direction are the same, there is almost no possibility that the second air flow enters the first air flow path 18, but the tip 114 and the tip 201 If the positions in the axial direction of the above are the same, the first air flow may enter the second air flow path 19.

FIG. 4 shows a second embodiment. In this second embodiment, the axial position of the tip 124 is farther from the suction port 22 than the axial position of the tip 202. In this case, it is possible to more reliably prevent the air flowing in the second passage 14B from entering the first air passage 18 after being converted to the second turning surface 122 and separated from the second turning surface 122. .. However, in this case, since the opening area of the outlet of the second air flow path 19 becomes small, the amount of air supplied becomes slightly small.

In the first and second embodiments, the separation cylinder 14 is integrally molded, preferably by resin injection molding. Since the gap between the first guide portion 110 (first wall portion 141) and the second guide portion 120 (second wall portion 142) is formed by using the drawing core, the drawing core is pulled out. The angle between the surface on the back side of the first turning surface 112 of the first guide portion 110 and the surface on the back side of the second turning surface 122 of the second guide portion 120 is determined so that the angle can be determined. Since the shape of these back surfaces has almost no effect on the air flow guidance performance, the drawn core can be designed only in consideration of the ease of core removal.

In the embodiments shown in FIGS. 3 and 4, it is described so that nothing exists in the space between the first guide unit 110 and the second guide unit 120. However, a plurality of ribs extending in the axial direction in the space between the first guide portion 110 and the second guide portion 120 are provided, and the first guide portion 110 and the second guide portion 120 are connected by these plurality of ribs. You may. The plurality of ribs can be provided, for example, at equal intervals in the circumferential direction of the separation cylinder 14. There is almost no effect on the air flow guidance performance by providing the ribs. Further, the production quality can be improved by providing the ribs.

It is also conceivable that the axial gap between the first guide portion 110 and the second guide portion 120 is completely filled. This has almost no effect on the air flow guidance performance. However, in this case, since the wall portion is thick, shrinkage is likely to occur during resin injection molding, which makes it difficult to manufacture the separation cylinder 14, which is not preferable. For example, shrinkage may occur and unintended deformation may occur after resin injection molding. In addition, it becomes difficult to reduce the weight of the product. In this case, the first turning surface 112 and the second turning surface 122 are formed by the front surface and the back surface of the same wall portion of the separation cylinder 14, and the above-mentioned "first guide portion 110 and second guide portion 120" are formed. Does not correspond to the feature that "is composed of different parts of the separation cylinder 14".

In the third embodiment shown in FIG. 5, unlike the first and second embodiments described above, the first guide portion 110 and the second guide portion 120 are separately manufactured and then joined. Joining can be performed by welding, adhesion, or the like. That is, in this case, a joint 145 composed of an adhesive portion or a welded portion is formed between the base end of the first guide portion 110 (first wall portion 141) and the base end of the second guide portion 120 (second wall portion 142). It will exist. In the first and second embodiments, since the first guide portion 110 and the second guide portion 120 are integrally molded, there is no joint formed of an adhesive portion or a welded portion between the base ends of both.

Next, the fourth embodiment will be described with reference to FIG. The separation cylinder 14 according to the fourth embodiment has a first curved wall portion 141A and a second curved wall portion 142A located inside the blade row 3A of the impeller 2 in the radial direction. The base end of the second curved wall portion 142A is connected to the tip of the first curved wall portion 141A. Looking at the meridional cross section of the centrifugal blower 1, the first curved wall portion 141A and the second curved wall portion 142A meander in a W shape as a whole. The first curved wall portion 141A constitutes the first guide portion 110, and the second curved wall portion 142A constitutes the second guide portion 120.

Looking at the meridional cross section of the centrifugal blower 1, the tangent TL at the tip of the first turning surface 112 of the first guide portion 110 composed of the first curved wall portion 141A faces the first air flow path 18 of the partition wall 20. It intersects with the surface 203 (the surface of the partition wall 20). The tangent TL may extend in the first air flow path 18 without intersecting the surface 203.

The definition of "tangent TL at the tip of the first turning surface 112" will be described. Looking at the meridional cross section of the centrifugal blower 1, the inclination angle θ with respect to the axial direction (direction of the rotation axis Ax) of the tangent line of the first turning surface 112 is the lower side in the rotation axis Ax direction in the drawing (the side far from the suction port 22). It gradually increases as it goes to, reaches the maximum value, and then gradually decreases. The "tangent line TL at the tip of the first turning surface 112" is defined as the tangent line of the first turning surface 112 when the inclination angle θ takes the maximum value.

Further, when viewed in the meridional cross section of the centrifugal blower 1, the axial position of the tip 124 of the second turning surface 122 of the second guide portion 120 is the tip 202 of the surface of the partition wall 20 facing the second air flow path 19. It is at the same position as the axial position or at a position farther from the suction port 22. This point is the same as that of the second guide unit 120 in the first to third embodiments.

Also in this fourth embodiment, it is possible to prevent or minimize the invasion of the air flowing in the first passage 14A into the second air passage 19, and the air flowing in the second passage 14B. Can be prevented or minimized from entering the first air passage 18.

As shown in FIG. 6, when viewed in the meridional cross section of the centrifugal blower 1, the tip of the contour line of the first turning surface 112 of the first guide portion 110 is the second turning surface of the second guide portion 120. If it is smoothly connected to the base end of the contour line of 122 (that is, when the inclination angle θ gradually increases as it approaches the tip before and after the tip of the first turning surface 112), the first guide portion 110 The air flowing near the surface of the first turning surface 112 may flow along the back surface of the second turning surface 122 of the second guide portion 120 without being separated from the first turning surface 112. In order to prevent such an event, a rectifying projection 113 as shown in FIG. 7 may be provided at the tip of the first guide portion 110. By providing such a rectifying projection 113, the air flowing near the surface of the first guide portion 110 first turning surface 112 tends to flow in the direction of the tangent line TL.

In the embodiment shown in FIGS. 3 to 6, when viewed in the meridional cross section of the centrifugal blower 1, the contour lines of the front and back surfaces of the tip portions of the first guide portion 110 and the second guide portion 120 are mutually aligned. The present invention is not limited to this, although it extends in parallel and the peripheral surfaces of the tips of the first guide portion 110 and the second guide portion 120 are parallel to the axial direction. For example, chamfering may be performed around the tips 114 and 124 of the first guide portion 110 and / or the second guide portion 120. Further, for example, the vicinity of the tips 114 and 124 of the first guide portion 110 and / or the second guide portion 120 may be shaped like a trailing edge portion of an airfoil (tapered shape). Further, the contour of the tips 114 and 124 of the first guide portion 110 and / or the second guide portion 120 as viewed from the axial direction may have a shape other than a perfect circle. Further, the inclination angle of the tip portion of the second turning surface may be larger than the inclination angle of the tip portion of the first turning surface 112 (meaning the inclination angle with respect to the horizontal plane, that is, the plane orthogonal to the axial direction). As a result, a part of the air flowing through the second passage 14B enters the first air passage 18 more reliably, and a part of the air flowing through the first passage 14A enters the second air passage 19. Can be prevented or minimized.

Next, the fifth embodiment will be described with reference to FIGS. 8 to 11. In the separation cylinder 14 according to the fifth embodiment, the first guide portion 110 has a plurality of (three in this case) first wall portions 1411, 1412, 1413 provided at intervals in the axial direction. .. The second guide portion 120 has one second wall portion 142 as in other embodiments. By configuring the first guide portion 110 with a plurality (three) first wall portions 1411, 1412, 1413, the first wall portion 1411 (suction) which serves as the first turning surface 112 of the first guide portion 110. The axial distance between the tip 114 of the surface of the first wall portion closest to the mouth 22) and the tip 201 of the partition wall 20 can be increased. As a result, it is possible to more reliably prevent or suppress the air flowing in the first passage 14A from entering the second air passage 19.

Even when the first guide portion 110 is composed of a single thick wall portion, the axial distance between the first guide portion 110 and the tip 201 of the partition wall 20 can be increased, and the same flow guidance function as in the fifth embodiment can be provided. Can be fulfilled. However, since the separation cylinder 14 is manufactured by the resin injection molding technique, there is a problem that shrinkage (molding failure) is likely to occur in the thick wall portion and deformation due to shrinkage is likely to occur. Further, if the first guide portion 110 is composed of a single thick wall portion, the weight of the first guide portion 110 near the free end (lower end in the drawing) of the separation cylinder 14 increases, which is contrary to the weight reduction of the product. ..

In the fifth embodiment, the thickness of the first guide portion 110, that is, the length in the axial direction is increased, so that the air passage between the first passage 14A and the first air passage 18 of the scroll housing 20 is narrow. Become. Therefore, the flow rate of the air flowing into the first air flow path 18 may be reduced. In order to alleviate this problem, in the fifth embodiment, the first wall portions 1411, 1412 are removed in the region near the tongue portion 17t of the scroll housing 20.

As shown in FIG. 9, the rotation direction of the impeller 2 (FIGS. 9 and 10) is defined as the position of the straight line 17s connecting the center 17p of the tongue portion 17t of the scroll housing 20 and the rotation axis Ax as the reference angle position (0 degree). Then, the angle measured in the clockwise direction) is called the winding angle.

In the fifth embodiment, as shown in FIGS. 10 and 11, the first guide portion 110 is in an angle range (a range of φ in FIG. 10) from a winding angle of zero degrees to a predetermined angle (for example, 45 degrees). Does not have the first wall portions 1411, 1412, but has only the first wall portion 1413. Since the flow rate of air flowing into the scroll housing 20 is small in the vicinity of the tongue portion 17t and in the range where the winding angle is positive, if the first wall portions 1411, 1412 are provided, the first air flow path of the scroll housing 20 is provided. The air flow rate flowing into 18 becomes very small. However, by removing the first wall portions 1411, 1412 as shown in FIGS. 10 and 11, the air flow rate flowing into the first air flow path 18 can be increased even in the range (φ).

In the range of φ, the air flow rate (that is, the flow velocity) flowing into the first air flow path 18 from the first passage 14A is originally small, so that the air flowing out from the first passage 14A flows into the second air flow path 19 due to inertia. I rarely go to. Therefore, even if the first wall portions 1411, 1412 are removed in the range of φ, there is almost no demerit.

In the fifth embodiment, in a range other than the above-mentioned range of φ, the surface that serves as the first turning surface 112 (that is, the surface that is closest to the suction port 22 among the three first wall portions that constitute the first guide portion 110). The positional relationship between the tip 114 of the first wall portion 1411 (the surface closer to the suction port 22) and the tip 201 of the partition wall 20 in the axial direction is the tip 114 and the tip 201 in the embodiments shown in FIGS. 3 to 5. It can be the same as the positional relationship with. Further, the positional relationship between the tip 124 of the second turning surface 122 and the tip 202 of the partition wall 20 in the axial direction is the same as the positional relationship between the tip 124 and the tip 202 in the embodiments shown in FIGS. 3 to 5. be able to.

In the fifth embodiment, within the range of φ, the tip of the surface 112'on the side close to the suction port 22 of the first wall portion 1413, which is a surface that serves as the first turning surface 112 in the other embodiments. The positional relationship between 114'(see FIG. 11) and the tip 201 of the partition wall 20 in the axial direction may be the same as the positional relationship between the tip 114 and the tip 201 in the embodiments shown in FIGS. 3 to 5. it can.

In the fifth embodiment, the axial position of the gap between the first wall portion 1412, which is the wall portion farthest from the suction port 22 of the first guide portion 110, and the second wall portion of the second guide portion 120, is determined. It can be matched with the axial position of the thickness of the partition wall 20.

In the fifth embodiment, a plurality of ribs for bridging the three first wall portions 1411, 1412, 1413 constituting the first guide portion 110 in the rotation axis (Ax) direction are equidistantly spaced in the circumferential direction of, for example, the separation cylinder 14. It may be provided by. Each rib may be extended to the second wall portion 142 constituting the second guide portion 120. By providing such ribs, the molding quality and rigidity of the corresponding portion of the separation cylinder 14 can be improved.

The number of the first wall portions (1411, 1412, 1413) constituting the first guide portion 110 is preferably three as shown, but is not limited to this, and may be two or four or more. But it may be.

1 Centrifugal blower 2 Impeller 3 Impeller blade 3A Impeller blade row 13 Motor 14 Separation cylinder 17 Scroll housing 170 Scroll housing discharge port 18 1st air flow path 19 2nd air flow path 20 Partition wall 201,202 Partition Wall tip 203 Partition wall surface 22 Scroll housing suction port 110 1st guide part 112 1st turning surface 114 1st turning surface tip 120 2nd guide part 122 2nd turning surface 124 2nd turning surface tip 141 1411-1413 1st wall 141A 1st curved wall 142 2nd wall 142A 2nd curved wall 145 Joint TL tangent

Claims (7)

It is a one-suction type centrifugal blower for vehicles.
With the motor
Air that has a plurality of blades forming a blade row arranged in the circumferential direction, is rotationally driven around the rotation axis by the motor, and is sucked into the space inside the radial direction of the blade row from one end side in the axial direction. An impeller that blows out in the radial direction,
A scroll housing having an internal space for accommodating the impeller, a suction port opening on one end side in the axial direction, and a discharge port opening in the circumferential direction.
The region between the inner peripheral surface of the scroll housing and the outer peripheral surface of the impeller in the internal space of the scroll housing, and the internal space of the discharge port are divided in the axial direction to form a first air flow. The partition wall forming the path and the second air flow path,
A separation cylinder extending in the axial direction from the inside of the suction port in the radial direction to the inside of the blade row in the radial direction, and the flow of air sucked into the scroll housing from the suction port is outside the separation cylinder. A separation cylinder that divides a first air flow that passes through the above separation cylinder and a second air flow that passes through the inside of the separation cylinder is provided.
The separation cylinder has a first guide portion and a second guide portion located inside the blade row in the radial direction, and the first guide portion and the second guide portion are different portions of the separation cylinder. The first guide portion has a first turning surface for turning the first air flow outward in the radial direction, and the second guide portion turns the second air flow outward in the radial direction. Centrifugal blower with a second turning surface. When viewed in the meridional cross section of the centrifugal blower, the tip portion of the separation cylinder is branched to form the first wall portion and the second wall portion, and the base end of the first wall portion and the second wall portion are formed. Is connected, the tip of the first wall and the tip of the second wall are separated, and the axial position of the tip of the second wall is the axis of the tip of the first wall. The centrifugal blower according to claim 1, which is located farther from the suction port than the directional position, the first wall portion constitutes the first guide portion, and the second wall portion constitutes the second guide portion. .. When viewed in the meridional cross section of the centrifugal blower, the axial position of the tip of the first turning surface of the first guide portion is the axial position of the tip of the surface of the partition wall facing the first air flow path. The axial position of the tip of the second turning surface of the second guide portion is the axial position of the tip of the surface of the partition wall facing the second air flow path. The centrifugal blower according to claim 2, which is located at the same position as or at a position farther from the suction port. The centrifugal blower for a vehicle according to claim 2 or 3, wherein a joint formed of an adhesive portion or a welded portion is present between the base end of the first wall portion and the base end of the second wall portion. The centrifugal blower for a vehicle according to claim 2 or 3, wherein there is no joint formed of an adhesive portion or a welded portion between the base end of the first wall portion and the base end of the second wall portion. When viewed in the meridional cross section of the centrifugal blower, the separation cylinder has a first curved wall portion and a second curved wall portion having a base end connected to the tip of the first curved wall portion, and the first curved wall portion. The centrifugal blower according to claim 1, wherein the wall portion constitutes the first guide portion, and the second curved wall portion constitutes the second guide portion. When viewed in the meridional cross section of the centrifugal blower, the tangent line at the tip of the first turning surface of the first guide portion intersects with or faces the surface of the partition wall facing the first air flow path. The axial position of the tip of the second turning surface of the second guide portion extends in the first air flow path without intersecting with the tip of the surface of the partition wall facing the second air flow path. The centrifugal blower according to claim 6, which is located at the same position as the axial position of the above or at a position farther from the suction port.

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