Vehicular air conditioner

Abstract

To suppress increase in ventilation resistance of a filter arranged at an inlet side of an air blowing unit.SOLUTION: A vehicular air conditioner (100) comprises: a duct (20) in which an air-blowing passage (21) is formed; an air-blowing unit (30) provided on the air-blowing passage (21); and a filter (50) arranged at an inlet side of the air-blowing unit (30) in the air-blowing passage (21). The air-blowing unit (30) is constituted of an axial-flow fan (31) in which a shaft line (CL) of a rotary shaft (33) extends along the air-blowing passage (21). The filter (50) has a filtering medium (60) having a pleat (61) in a mountain / valley shape formed thereon. The filtering medium (60) has a radial part (63) in which the pleat (61) extends radially from an aggregation part (62) where the pleat (61) aggregates, and a spiral part (64) in which the pleat (61) extends spirally at an outer diameter of the radial part (63).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an improved technology for a vehicle air conditioner. [Background technology]

[0002] The vehicle air conditioning system includes a blower unit and a cooling heat exchanger disposed within a casing. The blower unit uses, for example, a centrifugal fan. The centrifugal fan draws in air (airflow) from one axial side and blows it outward in the radial direction. The cooling heat exchanger is disposed on the other axial side of the centrifugal fan and cools the air blown out from the centrifugal fan using a refrigerant. The wind speed distribution of the air blown out from the centrifugal fan varies depending on the radial position. More specifically, almost no wind flows along the axis, while much air flows at positions radially away from the axis. Patent Document 1, for example, is known as a technology for suppressing this bias in the wind speed distribution of the air.

[0003] The vehicle air conditioning system known from Patent Document 1 has a filter interposed between a centrifugal fan disposed within a casing and a cooling heat exchanger. The filter includes a filter material for filtering air blown from a centrifugal blower toward the cooling heat exchanger. The filter material is formed into a wave shape (corresponding to pleats) by folding along a plurality of folds extending radially from the axis of the centrifugal fan. The folds extend in a vertical direction. Therefore, the filter material can suppress bias in the pressure loss in the vertical direction on a surface perpendicular to the axial direction, thereby suppressing bias in the air velocity distribution. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2021-187286 Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, the air drawn in from outside the vehicle by the blower unit (centrifugal fan) contains dust and moisture. To maintain the performance and durability of the centrifugal fan, it is preferable to remove the dust and moisture. To achieve this, it is possible to place a filter on the intake side of the centrifugal fan. However, the air drawn in by the centrifugal fan becomes a swirling flow. Simply placing the filter on the intake side of the centrifugal fan raises concerns that the filter's airflow resistance will increase against the swirling intake air.

[0006] Therefore, an object of the present invention is to provide a technology that can suppress an increase in the airflow resistance of a filter disposed on the suction side of an air blower unit in a vehicle air conditioner. [Means for solving the problem]

[0007] In the following description, reference numerals in the accompanying drawings are placed in parentheses to facilitate understanding of the present invention, but the present invention is not limited to the illustrated forms.

[0008] According to the present disclosure, there is provided a vehicle air conditioner (10; 100; 200) including a duct (20) having an air flow path (21) formed therein, an air blowing unit (30) provided in the air flow path (21), and a filter (50; 150; 250) arranged on the suction side of the air blowing unit (30) in the air flow path (21), The air blowing unit (30) is configured by an axial flow fan (31) having an axis (CL) of a rotation shaft (33) extending along the air blowing path (21), The filter (50; 150; 250) has a filter material (60; 160; 260) on which peak-valley pleats (61) are formed, The filter material (60; 160; 260) has a radial portion (63) where the pleats (61) extend radially from a gathering portion (62) where the pleats (61) gather, and a spiral portion (64) where the pleats (61) extend spirally outside the diameter of the radial portion (63). [Effects of the Invention]

[0009] According to the present invention, an increase in the airflow resistance of the filter disposed on the suction side of the blower unit can be suppressed. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view illustrating a vehicle air conditioner according to a first embodiment. [Figure 2] 2A is a view of the filter shown in FIG. 1 from the axial fan side, FIG. 2B is a view of the filter material as seen from the arrow 2B side of FIG. 2A, FIG. 2C is a cross-sectional view along line 2C-2C of FIG. 2A, FIG. 2D is a cross-sectional view along line 2D-2D of FIG. 2A, and FIG. 2E is a cross-sectional view along line 2E-2E of FIG. 2A. [Figure 3] FIG. 3A is an explanatory diagram of the operation of the filter medium shown in FIG. 2A, and FIG. 3B is an enlarged view of a portion of the filter medium shown in FIG. 3A. [Figure 4] Figure 4A is a process diagram for forming a pleated body in the filter manufacturing method of Example 1, Figure 4B is a diagram of the pleated body unfolded, Figure 4C is a process diagram for folding the pleated body and joining one end, Figure 4D is a process diagram for unfolding the pleated body, Figure 4E is a process diagram for joining the unfolded pleated body, and Figure 4F is a process diagram for fitting a filter material made of a pleated body into a frame. [Figure 5] FIG. 6 is a cross-sectional view illustrating a vehicle air conditioner according to a second embodiment. [Figure 6] 6A is a view of the filter shown in FIG. 5 as seen from the axial fan side, FIG. 6B is a view of the filter material as seen from the arrow 6B side of FIG. 6A, and FIG. 6C is a cross-sectional view taken along line 6C-6C of FIG. 6A. [Figure 7] FIG. 10 is a cross-sectional view illustrating a vehicle air conditioner according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings. Note that the embodiments shown in the accompanying drawings are merely examples of the present invention, and the present invention is not limited to these embodiments.

[0012] Example 1 1 to 4, a vehicle air conditioner 10 according to a first embodiment will be described. As shown in FIG. 1, the vehicle air conditioner 10 includes a duct 20, a blower unit 30, a cooling heat exchanger 40, and a filter 50.

[0013] The duct 20 (housing 20) is formed to have, for example, a circular or rectangular cross section. An air flow path 21 is formed inside the duct 20, through which air Fa (air flow Fa) taken in from inside or outside the vehicle compartment can circulate. A blower unit 30, a cooling heat exchanger 40, and a filter 50 are provided in the air flow path 21.

[0014] The blower unit 30 blows air Fa (air flow Fa) taken in from inside or outside the vehicle cabin into the vehicle cabin. The blower unit 30 is configured with an axial fan 31 having an axis CL of a rotary shaft 33 extending along an air flow path 21. Here, within the air flow path 21, a passage 22 on the suction side of the axial fan 31 is sometimes referred to as the "suction-side passage 22," and a passage 23 on the discharge side of the axial fan 31 is sometimes referred to as the "discharge-side passage 23."

[0015] The axial fan 31 draws in an airflow Fa from one side in the axial direction Rs (the suction-side passage 22) and blows it to the other side in the axial direction Rs (the discharge-side passage 23). More specifically, the axial fan 31 includes a fan housing 32, a rotating shaft 33 rotatably housed within the fan housing 32, rotor blades 34 (rotor blades 34) housed within the fan housing 32 and mounted on the rotating shaft 33, stator blades 35 housed within the fan housing 32 and positioned behind the rotor blades 34, and an electric motor 36 that drives the rotor shaft 33. The stator blades 35 regulate the swirling flow generated behind the rotor blades 34 and redirect it into an axial flow.

[0016] The fan housing 32 includes a cylindrical housing body 32a and a cover portion 32b provided on the suction side (upstream side) of the housing body 32a. The housing body 32a is fitted, for example, onto the inner circumferential surface 20a of the duct 20. The cover portion 32b is formed, for example, in a conical shape that protrudes from the housing body 32a toward the upstream side, and has a suction port 32c at its tip. The suction port 32c is a circular hole located on the axis CL of the rotation shaft 33. The discharge port 32d of the housing body 32a is a hole that opens the entire housing body 32a.

[0017] The electric motor 36 is fixed to the fan housing 32. The motor shaft of the electric motor 36 may also serve as the rotary shaft 33.

[0018] The cooling heat exchanger 40 (evaporator 40) is disposed downstream (discharge side passage 23) of the axial fan 31 in the air blowing path 21. The cooling heat exchanger 40 cools the air blown from the axial fan 31 by exchanging heat between the air and a refrigerant in a refrigeration cycle (not shown).

[0019] The filter 50 can promote uniformity of the wind speed distribution of the airflow Fa flowing through the airflow path 21. Furthermore, the filter 50 can remove foreign matter such as dust and mist mixed in the airflow Fa. The filter 50 is disposed on the suction side (suction-side passage 22) of the axial flow fan 31 in the airflow path 21, and is arranged on the axis CL of the rotary shaft 33, for example.

[0020] The filter 50 includes a sheet-like (including film-like) filter medium 60 that allows airflow Fa to pass through, and a frame 70 that surrounds the outer periphery of the filter medium 60. The filter medium 60 is made of, for example, a woven fabric made of various fibers, or a nonwoven fabric such as filter paper or felt. Referring also to FIG. 2A, the filter medium 60 is formed in a circular shape when viewed along the axis CL of the rotating shaft 33, and is surrounded by and fixed to the circular frame 70.

[0021] FIG. 2A shows the configuration of filter medium 60 as viewed from the downstream side, i.e., from the axial fan 31 side (see FIG. 1). As shown in FIGS. 2A to 2E, this filter medium 60 has mountain-valley pleats 61 formed therein. These pleats 61 are "pleats" or "creases" with clearly defined ridges. More specifically, in filter medium 60, pleats 61 extend radially from a collection portion 62 where the pleats 61 are gathered. Collection portion 62 is located on the axis CL of rotation shaft 33 (see FIG. 1). In other words, when this filter medium 60 is viewed along the axis CL of rotation shaft 33, pleats 61 are configured such that mountain folds 61a and valley folds 61b are alternately arranged in the circumferential direction. Here, mountain folds 61a are apexes that protrude toward the axial fan 31 side (see FIG. 1), and valley folds 61b are bottoms that are recessed away from the axial fan 31. For example, when the filter medium 60 is viewed along the axis CL of the rotary shaft 33, the mountain folds 61a are provided at equal angles with the collection portion 62 as the center.

[0022] 2A, 2D, and 2E, when this filter medium 60 is viewed along the axis CL of the rotation shaft 33, the pleat depth De formed by the mountain folds 61a and the valley folds 61b of the pleats 61 becomes deeper as it approaches the collection portion 62 in the radial direction of the axis CL. That is, as shown in FIGS. 2A and 2C, the pleat depth (outer pleat depth) of the outermost pleats 61 in the radial direction of the filter medium 60 is D1. The pleat depth (center pleat depth) of the pleats 61 at the collection portion 62 of the filter medium 60 is D2. The center pleat depth D2 is greater than the outer pleat depth D1.

[0023] Therefore, as shown in Figures 1 and 2A, the air Fa sucked in by the axial fan 31 from an area radially away from the axis CL (radially outward) can also flow into the vicinity of the collection section 62, which has a large pleat depth De and low air resistance.

[0024] 2A and 3A show the configuration of the filter medium 60 as seen from the downstream side, i.e., from the axial fan 31 side (see FIG. 1). The filter medium 60 has a radial portion 63 where the pleats 61 extend radially from a collection portion 62 where the pleats 61 are collected, and a spiral portion 64 where the pleats 61 extend spirally outside the diameter of the radial portion 63 (radially outward from the outer edge 63a of the radial portion 63). The pleats 61 are continuous between the radial portion 63 and the spiral portion 64. The boundary between the outer edge 63a of the radial portion 63 and the inner edge 64a of the spiral portion 64 is the bending point where the pleats 61 change from radial to spiral.

[0025] The spiral direction of the pleats 61 within the spiral portion 64 is aligned with the swirling direction Ru (see FIG. 3A) of the intake air Fa that is sucked into the axial fan 31 and flows as a swirling flow. Therefore, at least a portion of the intake air Fa that flows as a swirling flow passes through the pleats 61 of the spiral portion 64. Moreover, as shown in FIG. 3B, the intake air Fa that flows as a swirling flow passes over the mountain folds 61a and is guided to the radial portions 63 along the spiral direction.

[0026] 2A and 2C, when the filter medium 60 is viewed along the axis CL of the rotation shaft 33, the radius from the collection portion 62 to the outer edge 63a of the radial portion 63 (radial portion radius) is r1, and the distance from the inner edge 64a of the spiral portion 64 (outer edge 63a of the radial portion 63) to the outer edge 64b (spiral portion radius) is r2. The spiral portion radius r2 is set to be longer than the radial portion radius r1.

[0027] When the filter 50 is viewed along the axis CL of the rotating shaft 33, the filter material 60 may be circular or rectangular, and may be configured to be surrounded and fixed by a circular or rectangular frame body 70.

[0028] Next, an example of a method for manufacturing the filter 50 of the first embodiment will be described with reference to FIGS. 4A to 4F. First, as shown in FIG. 4A, a sheet-like filter medium 60 is pleated to obtain a pleated body 81 shown in FIG. 4B. Next, as shown in FIG. 4C, the pleated body 81 is folded and one end 81a corresponding to the collection portion 62 (see FIG. 2A) is joined. Next, as shown in FIG. 4D, the pleated body 81 is unfolded around one end 81a. Next, as shown in FIG. 4E, the unfolded pleated body 81 is joined so as not to close. This results in a filter medium 60 with pleats 61 formed. Finally, as shown in FIG. 4F, the filter medium 60 with pleats 61 formed is fitted into a frame 70 and fixed. This completes the production of the filter 50.

[0029] <Example 2> Second Embodiment A vehicle air conditioner 100 according to a second embodiment will be described with reference to Figures 5 and 6. Figure 5 corresponds to Figure 1, and Figure 6 corresponds to Figure 2.

[0030] The vehicle air conditioner 100 of the second embodiment is characterized in that the filter material 60 of the filter 50 of the first embodiment shown in Figures 1 to 4 is replaced with the filter material 160 of the filter 150 shown in Figures 5 and 6. The other configuration of the vehicle air conditioner 100 is common to the vehicle air conditioner 10 of the first embodiment. The same reference numerals are used for the parts common to the vehicle air conditioner 10 of the first embodiment, and detailed explanations thereof will be omitted.

[0031] The filter 150 of Example 2 includes a filter medium 160 and a frame 70 that surrounds the outer periphery of the filter medium 160. The filter medium 160 has the same basic configuration as the filter medium 60 shown in Fig. 2. The filter medium 160 has peak-valley pleats 61 formed therein. More specifically, the filter medium 160 has a radial portion 63 in which the pleats 61 extend radially from a collection portion 62 in which the pleats 61 are collected, and a spiral portion 64 in which the pleats 61 extend spirally outside the diameter of the radial portion 63.

[0032] The filter medium 160 of the second embodiment has a conical or pyramidal configuration and is surrounded by and fixed to a circular or rectangular frame 70. When this pyramidal or conical filter medium 160 is viewed along the axis CL of the rotary shaft 33, the collection portion 162 is located at the most upstream side of the filter medium 160. In other words, the collection portion 62 is located at the farthest position of the filter medium 160 from the suction port 32c of the axial flow fan 31. Therefore, the intake air Fa that is sucked into the axial flow fan 31 and flows as a swirling flow can be smoothly collected in the collection portion 62.

[0033] Example 3 A vehicle air conditioner 200 according to a third embodiment will be described with reference to Fig. 7. Fig. 7 corresponds to Fig. 5 above. The vehicle air conditioner 200 according to the third embodiment is characterized in that the filter material 160 of the filter 150 according to the second embodiment shown in Figs. 5 and 6 above is replaced with the filter material 260 of the filter 250 shown in Fig. 7. The other configurations of the vehicle air conditioner 200 are common to the vehicle air conditioners 10.100 according to the first and second embodiments. The same reference numerals will be used for parts common to the vehicle air conditioners 10.100 according to the first and second embodiments, and detailed descriptions thereof will be omitted.

[0034] The filter 250 of Example 3 is disposed in the opposite direction to the filter 150 of Example 2 in the axial direction Rs. When the pyramidal or conical filter medium 260 is viewed along the axis CL of the rotation shaft 33, the collection portion 62 is located on the most upstream side of the filter medium 260. In other words, the collection portion 62 is located closest to the suction port 32c of the axial fan 31 among the filter medium 260. However, the spiral direction of the pleats 61 within the spiral portion 64 of the filter medium 160 of Example 2 shown in FIG. 6A above is opposite to the spiral direction of the pleats 61 within the spiral portion 64 of the filter medium 260 of Example 3.

[0035] The vehicle air conditioners 10, 100, and 200 described above can be summarized as follows.

[0036] Please refer to Figures 1, 2, and 5 to 7. According to this embodiment, firstly, a vehicle air conditioner 10; 100; 200 includes a duct 20 having an air flow path 21 formed therein, a blower unit 30 provided in the air flow path 21, and a filter 50; 150; 250 arranged on the suction side of the blower unit 30 within the air flow path 21. The blower unit 30 is configured by an axial flow fan 31 having an axis CL of a rotary shaft 33 extending along the air flow path 21. The filter 50; 150; 250 has a filter medium 60; 160; 260 on which peak-valley pleats 61 are formed. The filter material 60; 160; 260 has a radial portion 63 where the pleats 61 extend radially from a collection portion 62 where the pleats 61 are collected, and a spiral portion 64 where the pleats 61 extend spirally outside the diameter of this radial portion 63.

[0037] In this way, the pleats 61 are formed in a spiral shape outside the radial portion 63. The direction of the spiral can be aligned with the swirling direction Ru of the intake air Fa that is sucked into the axial fan 31 and flows as a swirling flow. At least a portion of the intake air Fa that flows as a swirling flow passes through the pleats 61 of the spiral portion 64. Therefore, the filter 50; 150; 250 can suppress an increase in ventilation resistance to the intake air Fa of the axial fan 31 that flows as a swirling flow.

[0038] See Figures 1, 2, 6, and 7. Secondly, preferably, in the vehicle air conditioner 10; 100; 200 described above, when viewed along the axis CL of the rotation shaft 33, the filter material 60; 160; 260 has a spiral portion radius r2 from the inner edge 64a to the outer edge 64b of the spiral portion 64 longer than the radial portion radius r1 from the collection portion 62 to the outer edge 63a of the radial portion 63. In this way, since the spiral portion radius r2 is longer than the radial portion radius r1, the filter material 60; 160; 260 has a spiral portion 64 having an area three or more times larger than that of the radial portion 63. Therefore, when the axial flow fan 31 is operated, the proportion of air Fa passing through the pleats 61 of the spiral portion 64 can be increased, more reliably suppressing an increase in ventilation resistance.

[0039] See Fig. 5. Thirdly, preferably, in the vehicle air conditioner 100 described in the first aspect, the filter medium 160 is pyramidal or conical. When this filter medium 160 is viewed along the axis CL of the rotary shaft 33, the collection portion 62 is located at the most upstream side of the filter medium 160. This ensures a sufficient volume for the flow path from the collection portion 62 to the suction side of the blower unit 30. This equalizes the distance between the filter 150 and the suction side of the blower unit 30, preventing the air Fa passing through the filter 150 from flowing locally, thereby improving the air blowing efficiency of the vehicle air conditioner 100.

[0040] See Fig. 7. Fourth, preferably, in the vehicle air conditioner 200 described in the first aspect, the filter material 260 is pyramidal or conical. When the filter material 260 is viewed along the axis CL of the rotary shaft 33, the collection portion 62 is located at the most downstream side of the filter material 260. This increases the amount of filter material 260 in the filter, reducing airflow resistance and improving the air blowing efficiency of the vehicle air conditioner 200.

[0041] See Figures 2, 6 and 7. Fifth, preferably, in the vehicle air conditioners 10, 100, 200 described in any one of the first to fourth aspects, the filter material 60; 160; 260 is surrounded by and fixed to a rectangular or circular frame 70 when viewed along the axis CL of the rotary shaft 33. By surrounding the filter material 60; 160; 260 with the rectangular or circular frame 70 in this way, the pleats 61 can be firmly held so as not to be biased, and the filter material 60; 160; 260 can be attached to the air flow path 21.

[0042] As long as the functions and effects of the present invention are achieved, the present invention is not limited to the embodiments. For example, the vehicle air conditioners 10, 100, and 200 of the embodiments can be combined with any two or more embodiments. [Industrial Applicability]

[0043] The vehicle air conditioners 10, 100, 200 of the present invention are suitable for installation in vehicles such as passenger cars. [Explanation of symbols]

[0044] 10,100,200 Vehicle air conditioning system 20 Duct 21 Air flow path 30 Blower unit 31 Axial fan 33 Rotation axis 50, 150, 250 filters 60,160.260 Filter media 61 pleats 61a Mountain fold 61b Valley fold 62 Gathering area 63 Radial section 63a Outer edge of the radial part 64 Spiral part 64a Inner edge of the spiral 64b Outer edge of the spiral 70 Frame CL Axis of the rotating shaft Fa Air Flow Rs Axial direction r1 radial radius r2 Radius of the spiral

Claims

1. A vehicle air conditioner (10; 100; 200) comprising: a duct (20) having an air flow path (21) formed therein; an air blowing unit (30) provided in the air flow path (21); and a filter (50; 150; 250) arranged on the suction side of the air blowing unit (30) in the air flow path (21), The air blowing unit (30) is configured by an axial flow fan (31) having an axis (CL) of a rotation shaft (33) extending along the air blowing path (21), The filter (50; 150; 250) has a filter material (60; 160; 260) on which peak-valley pleats (61) are formed, The filter material (60; 160; 260) has a radial portion (63) in which the pleats (61) extend radially from a gathering portion (62) where the pleats (61) gather, and a spiral portion (64) in which the pleats (61) extend spirally outside the diameter of the radial portion (63).

2. 2. The vehicle air conditioning system according to claim 1, wherein, when viewed along the axis (CL) of the rotation shaft (33), a spiral portion radius (r2) from an inner edge (64a) to an outer edge (64b) of the spiral portion (64) is longer than a radial portion radius (r1) from the collection portion (62) to the outer edge (63a) of the radial portion (63).

3. The filter medium (60; 160; 260) is pyramidal or conical, 2. The vehicle air conditioning system according to claim 1, wherein the collection portion is located most upstream of the filter material when the filter material is viewed along the axis of the rotation shaft.

4. The filter medium (60; 160; 260) is pyramidal or conical, 2. The vehicle air conditioning system according to claim 1, wherein the collection portion is located at the most downstream side of the filter material when the filter material is viewed along the axis of the rotation shaft.

5. 5. The vehicle air conditioning system according to claim 1, wherein the filter material (60; 160; 260) is surrounded by and fixed to a rectangular or circular frame body (70) when viewed along the axis (CL) of the rotating shaft (33).

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