JP6714308B2 - Blower motor unit for air conditioning - Google Patents

Description

The present invention relates to an air conditioner blower motor unit having a casing containing a brushless motor and a circuit board.

In a vehicle air conditioner, a blower fan rotates under the action of a brushless motor that constitutes an air conditioning blower motor unit, and thereby blows air. An example of this type of air-conditioning blower motor unit is described in Patent Document 1.

In the blower motor unit for air conditioning described in Patent Document 1, a magnet sensor is provided in the vicinity of the lower end portion of the rotating shaft of the brushless motor, and a Hall element is provided on a circuit board having an insertion hole through which the rotating shaft is inserted. With this configuration, the rotation angle of the rotor that forms the brushless motor is detected by detecting the magnetic flux of the sensor magnet with the Hall element. The exciting current supplied to the stator is controlled based on the detection result.

On the other hand, as disclosed in Patent Document 2, an air conditioning blower motor unit that does not use a magnet sensor and a Hall element has been proposed. This air conditioner blower motor unit holds a stator (stator) of the brushless motor and has a stator base in which a cooling air introduction path for passing cooling air is formed. The circuit board is connected to the stator base via a partition plate made of resin. That is, the circuit board is supported by the stator base with the partition plate interposed between the circuit board and the stator base.

JP, 11-332203, A JP, 2005-80301, A

In the air-conditioning blower motor unit described in Patent Documents 1 and 2, the circuit board is provided so as to overlap the rotation shaft in plan view. Therefore, the dimension of the casing that houses the brushless motor along the axial direction of the rotating shaft (the thickness direction of the casing) becomes large. That is, it is difficult to reduce the size of the air conditioning blower motor unit in any of the above-mentioned conventional techniques.

Moreover, in the conventional technique described in Patent Document 1, as is clear from FIG. 1, the cooling air generated by the blower fan and flowing into the diversion duct is unlikely to contact the heat sink. Therefore, it is difficult for the circuit board to be cooled. On the other hand, also in the conventional technique described in Patent Document 2, it is considered that the circuit board is difficult to be cooled because the partition plate is interposed between the circuit board and the stator base on which the heat sink is formed. This is because the heat transfer from the circuit board is blocked by the partition plate.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a blower motor unit for air conditioning which can be downsized and which can efficiently cool a circuit board.

In order to achieve the above object, an air conditioner blower motor unit according to the present invention is a brushless motor for rotating a blower fan that constitutes an air conditioner,
A circuit board provided with a control circuit for controlling the brushless motor,
A support board that has a bearing portion that rotatably supports the rotation shaft of the brushless motor, and that supports the circuit board at an offset position where the circuit board does not overlap the bearing portion in plan view,
A casing that is configured by combining a first casing member and a second casing member, and that houses the brushless motor, the circuit board, and the support board,
Equipped with
The support board has a first surface facing the first casing member and a second surface facing the second casing member,
The circuit board is held on the second surface side of the support board,
On the first surface side of the support board, a heat dissipation portion capable of dissipating heat of the circuit board is formed integrally with the support board,
In the first casing member, an air introduction port, a rotation shaft insertion port through which the rotation shaft is passed, and a part of the air introduced from the air introduction port are passed through the heat dissipation unit and the brushless motor. A first flow passage is formed to circulate in the rotary shaft insertion opening ,
A second flow passage is formed in the second casing member for circulating the air introduced from the air introduction port, and the air is guided from the second flow passage to the first casing member side. The guide section of
The guide portion is Ri protruding projection der to form a substantially inverted V-shape oriented in the first casing member,
A clearance is formed between the protrusion and the circuit board,
The remainder of the air beyond the projection, from the clearance, characterized that you flow to said rotary shaft insertion opening through between the said circuit board second casing member.

First, since the circuit board is supported at the offset position where it does not overlap the bearing portion in plan view, the distance between the circuit board and the support board can be made smaller than in the arrangement in which the circuit board overlaps the bearing portion. As a result, the thickness of the air conditioning blower motor unit can be reduced. That is, miniaturization can be achieved.

Further, in the casing, there is provided a protrusion that is a guide portion that guides the air (cooling air) flowing through the flow passage in the casing and changes the traveling direction to the first casing member side. Therefore, the cooling air comes into efficient contact with the support board. Therefore, the heat of the circuit board supported by the support board is removed more quickly through the support board. In other words, the circuit board can be cooled efficiently.

The guide portion can be provided, for example, as a protruding portion that is directed toward the first casing member side and protrudes in a substantially inverted V shape. Such a guide portion (projection portion) may be configured by providing a solid projection portion (raised portion) inside the second casing member. Alternatively, since it is possible to reduce the weight more than this, the outer wall of the second casing member may be formed as a projecting portion that is bent toward the first casing member side.

In the latter case, a rib may be provided on a portion of the outer wall of the second casing member corresponding to the outer surface of the guide portion. This ensures the rigidity of the second casing member and prevents resonance of the casing in the audible range. That is, the vibration noise is reduced and the quietness is improved.

Further, it is preferable that the support board is elastically supported by the casing with a cushioning member interposed between the support disc and the casing. A clearance is formed between the guide part and the support plate so that the support plate does not interfere with the guide part when the rotating shaft rotates.

In this case, when the vibration generated when the rotary shaft rotates is transmitted to the support board, the cushioning member interposed between the support board and the casing performs a cushioning action. Vibrations are absorbed by this buffering action, so it is difficult for the vibrations to propagate to the casing. Moreover, since the support board does not interfere with the guide portion, it is possible to avoid the generation of interference noise and the damage of the circuit board. Therefore, the quietness is further improved and the durability is excellent.

In order to insert the cushioning member between the support board and the casing, for example, the cushioning member is configured to have a cylindrical portion, and the support board is provided with a tongue piece projecting from the outer edge portion thereof. Then, the cushioning member is held on the tongue piece. Further, the threaded portion provided on the first casing member is passed through the cylindrical portion of the cushioning member. In this state, when the screw member is screwed into the screw portion, the cushioning member is inserted between the head portion of the screw member and the screw portion. That is, the cushioning member can be easily inserted between the support board and the casing.

In the above configuration, it is preferable that the support board is arranged at a position where it comes into contact with air (cooling air) flowing from the air introduction port through the guide portion to the rotary shaft insertion port. This is because it is possible to more efficiently cool the support board and thus the circuit board.

According to the present invention, since the circuit board is supported at the offset position where it does not overlap the bearing portion in a plan view, the distance between the circuit board and the support board is smaller than the arrangement in which the circuit board overlaps the bearing portion. Can be made smaller. As a result, the thickness of the air conditioning blower motor unit can be reduced, so that the air conditioning blower motor unit can be downsized.

Further, in the casing, there is provided a protrusion that is a guide portion that guides the air (cooling air) flowing through the flow passage in the casing and changes the traveling direction to the first casing member side. Therefore, the cooling air efficiently comes into contact with the support board, so that the support board and the circuit board supported by the support board can be efficiently cooled.

It is a schematic whole perspective view of the air-conditioning blower motor unit which concerns on embodiment of this invention. It is a schematic longitudinal cross-sectional view of the blower motor unit for air conditioning of FIG. It is a schematic bottom view of the blower motor unit for air conditioning of FIG. It is a schematic whole perspective view of the support board which comprises the blower motor unit for air conditioning. FIG. 2 is an enlarged vertical cross-sectional view in which the vicinity of a bearing portion of a support board that constitutes the air conditioning blower motor unit of FIG. 1 is enlarged. It is the schematic bottom view which abbreviate|omitted illustration of the lower half which comprises the blower motor unit for air conditioning. It is the schematic plan view which abbreviate|omitted illustration of the upper half body which comprises the blower motor unit for air conditioning.

Hereinafter, preferred embodiments of an air conditioning blower motor unit according to the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the terms “upper” and “lower” below correspond to the upper side and the lower side in FIGS. 1 and 2.

1 to 3 are a schematic overall perspective view, a schematic vertical sectional view, and a schematic bottom view of an air conditioning blower motor unit 10 according to the present embodiment, respectively. The air-conditioning blower motor unit 10 has a brushless motor 12 and a casing 14 accommodating the brushless motor 12. The blower fan 16 shown in phantom in FIG. 2 is attached to the rotary shaft 68 of the brushless motor 12.

The casing 14 is configured by combining a lower half body 18 (second casing member) and an upper half body 20 (first casing member), both of which are made of resin. The lower half body 18 is a hollow body that is open on the side facing the upper half body 20, while the upper half body 20 is a hollow body that is open on the side facing the lower half body 18 (see particularly FIG. 2 ). That is, the lower half body 18 constitutes the bottom portion, and the upper half body 20 constitutes the ceiling portion. Therefore, the casing 14 is also configured as a hollow body, and the inside of the hollow serves as a passage for cooling air (air) introduced from the air introduction port 22 formed in the upper half body 20. The cooling air is generated by the rotating blower fan 16.

The lower half body 18 is configured by connecting a linear portion 24, a substantially circular portion 26, a small semicircular portion 28, and a protruding portion 30 from left to right in FIG. The linear portion 24 and the small semicircular portion 28 are formed with screw insertion holes 32a to 32c for inserting a connection screw (not shown) that connects the lower half body 18 to the upper half body 20. The screw insertion hole 32a of the linear portion 24 is formed at a position that does not hinder the flow of cooling air. Further, the screw insertion hole 32b is at a position where the phase difference is about 120° with respect to the screw insertion hole 32c formed in the vicinity of the boundary between the small semicircular portion 28 and the almost circular portion 26, and the coupler portion 40 to be described later. Is formed so as not to interfere with.

The linear portion 24 is formed with a protrusion 34 having a substantially inverted V shape by bending the bottom wall portion toward the upper half body 20 side. That is, the two side portions of the protrusion 34 are inclined portions. As will be described later, the protrusion 34 functions as a guide portion that guides the cooling air.

As shown in FIGS. 2 and 3, a rib 36 having a substantially triangular shape is bridged to the outer walls of the two inclined portions forming the protrusion 34. In other words, the rib 36 is provided on a portion of the outer wall of the lower half body 18 corresponding to the outer surface of the protrusion 34.

The mostly circular portion 26 has a larger diameter than the small semicircular portion 28, and shares a chord with the small semicircular portion 28 (see FIG. 3 ). For this reason, steps 38a and 38b along the secant direction are provided at the boundary between the mostly circular portion 26 and the small semicircular portion 28. The screw insertion hole 32c is formed in the step 38a. On the other hand, a coupler 40 for electrically connecting a harness (not shown) is exposed at the step 38b. That is, the coupler section 40 is provided so as to be adjacent to the lower half body 18.

In this coupler section 40, a plurality of (four in the present embodiment) bus bars 44a to 44d provided on a circuit board 42 (see FIGS. 2 and 6) housed in the substantially circular section 26 are provided with coupler housings. It is configured by being accommodated in 46. The coupler section 40 will be described later.

On the other hand, as shown in FIG. 2, the upper half body 20 is connected to a hollow cylindrical portion 50 in which the air introduction port 22 is formed, and is connected to the cylindrical portion 50 so as to have a substantially L-shape, and has the linear shape. It has a first lid portion 52 that closes the upper opening of the portion 24, and a second lid portion 54 that closes the upper openings of the majority circular portion 26 and the small semicircular portion 28. The second lid portion 54 has a substantially circular shape in a plan view, and at its peripheral portion, stay portions 56a to 56c for connecting the air conditioning blower motor unit 10 to a predetermined member (not shown) are approximately 120 in shape. It is provided so as to have a phase difference of °.

Screw holes 58a to 58c are provided at portions corresponding to the screw insertion holes 32a to 32c. That is, the body portion of the connecting screw passed through each of the screw insertion holes 32a to 32c is screwed into the screw holes 58a to 58c. As a result, the lower half 18 and the upper half 20 are connected to each other to form the casing 14. Further, the second lid portion 54 is provided with screwing boss portions 62a to 62c (screw portion) in which screw holes for supporting the support board 60 are formed.

An annular protrusion 64 is formed at the center of the second lid 54 so as to project upward. A rotary shaft insertion opening 66 having a slightly larger diameter is formed in the annular projection 64. The rotary shaft 68 of the brushless motor 12 is exposed from the rotary shaft insertion opening 66. On the other hand, the stator 70 and the rotor 72 that configure the brushless motor 12, the circuit board 42 that controls the brushless motor 12, and the like are housed in the casing 14 together with the support board 60.

Here, a schematic overall perspective view of the support board 60 is shown in FIG. The supporting plate 60 is made of metal, and is composed of a disk-shaped portion 80 and three tongue pieces that project from the outer peripheral edge portion of the disk-shaped portion 80 and are arranged at positions where a phase difference of about 120° is formed between them. It has rubber holding parts 82a to 82c. A heat sink portion 84 is provided between the rubber holding portions 82a and 82c.

The disk-shaped portion 80 has a thin plate shape in which a plurality of ventilation holes 86 (slits) are radially formed. Spoke portions 90 are formed between the adjacent ventilation holes 86, 86 in a radial pattern centered on a bearing portion 88 described later. As can be easily understood from FIG. 2, the spoke portion 90 is located at a position slightly separated from the bearing portion 88 toward the outer edge portion and on a surface facing the circuit board 42 in a direction separated from the circuit board 42. A raised dihedral angle 92 is provided. That is, the dihedral angle 92 is directed toward the upper half body 20 and is raised.

A cylindrical bearing portion 88 is provided at the center of the disk-shaped portion 80. The rotating shaft 68 of the brushless motor 12 is rotatably supported by the bearing 88 (see FIG. 2). Here, as shown in an enlarged manner in FIG. 5, the bearing portion 88 includes a first bearing accommodating portion 94 having a small outer diameter, a minimum inner diameter portion 96, and an expanded inner diameter from the lower end side facing the lower half body 18. The portion 98 and the second bearing accommodating portion 100 are provided in this order. The inner diameters of the first bearing accommodating portion 94 and the second bearing accommodating portion 100 are substantially equal to each other, while the inner diameters of the minimum inner diameter portion 96 and the expanded inner diameter portion 98 are the same as the first bearing accommodating portion 94 and the second bearing accommodating portion. Different from part 100. Thus, the inner diameter of the bearing portion 88 changes along the axial direction of the bearing portion 88.

The inner diameter of the first bearing accommodating portion 94 is equal in the vertical direction (axial direction), the first bearing 104 is slidably inserted, and the outer ring of the first bearing 104 holds the web washer 105 with a clamping force. To be done. The inner diameter of the smallest inner diameter portion 96 is also equal, and is set to the smallest in the bearing portion 88. That is, the bearing portion 88 is formed thickest in the smallest inner diameter portion 96, and therefore, the clearance between the inner peripheral wall of the smallest inner diameter portion 96 and the side peripheral wall of the rotary shaft 68 is extremely small. The spoke portion 90 is connected to the outer peripheral wall of the minimum inner diameter portion 96.

An expanded inner diameter portion 98 is arranged above the minimum inner diameter portion 96. In the expanded inner diameter portion 98, the inner diameter expands in a taper shape as it separates from the lower half body 18 (approaches the upper half body 20). That is, in the expanded inner diameter portion 98, the inner peripheral wall thereof is gradually separated from the side peripheral wall of the rotating shaft 68 as the upper half body 20 is approached. Therefore, the second bearing accommodating portion 100 connected to the expanded inner diameter portion 98 is flexible and has relatively large elasticity as compared with other portions.

The second bearing 106 is press-fitted into the second bearing housing portion 100 having an equal inner diameter. As described above, since the second bearing accommodating portion 100 has a large elasticity, it is easy to press-fit the second bearing 106. Moreover, after the press-fitting, the second bearing 106 is elastically biased toward the rotary shaft 68 under the elastic action of the second bearing housing portion 100. As a result, the inner ring of the second bearing 106 presses the outer peripheral wall of the rotating shaft 68 substantially uniformly.

On the outer peripheral wall of the expanded inner diameter portion 98, a press-fitting recess 108 into which a part of the stator 70 forming the brushless motor 12 is press-fitted is formed so as to be recessed radially inward. As shown in FIG. 2, the second bearing housing portion 100 is provided at a position apart (offset) from the stator 70 press-fitted into the press-fitting recess 108 in the axial direction of the bearing portion 88.

As shown in FIG. 4, in the vicinity of the bearing portion 88, a plurality of ventilation holes 86 (slits) extending from the inner peripheral side toward the outer peripheral side are radially formed. It goes without saying that the ventilation hole 86 penetrates along the vertical direction (the thickness direction of the disk-shaped portion 80).

An annular portion 109 is formed on the peripheral portion of the disc-shaped portion 80. The rubber holding portions 82a to 82c and the heat sink portion 84 project from the outer peripheral wall of the annular portion 109 (the outer peripheral edge portion of the disc-shaped portion 80).

Each of the rubber holding portions 82a to 82c has a ring shape in which a part of an arc is cut out, and thus has a substantially C shape in a plan view. The small-diameter middle abdomen of the cylindrical rubber member 110 is inserted into each of the rubber holding portions 82a to 82c. By this insertion, the cylindrical rubber member 110 is held by the rubber holding portions 82a to 82c. The large-diameter lower end portion and the upper end portion of the cylindrical rubber member 110 are exposed from the rubber holding portions 82a to 82c.

The heat sink portion 84 is a heat radiating portion having a large surface area by arranging a plurality of fins upright. That is, the heat sink portion 84 dissipates the heat of the circuit board 42 transmitted to the support board 60. The support board 60 is housed in the casing 14 with the lower surface of the heat sink portion 84 facing the protrusion 34 and the fins facing the upper half 20.

The rubber holding portions 82a and 82c and the heat sink portion 84 are formed with screwing boss portions 112a to 112c. A screw hole is formed in each of the screwing boss portions 112a to 112c, and a support screw 114 (see FIG. 2) for attaching the circuit board 42 to the support board 60 is screwed into the screw hole. Further, the mutual phase difference between the screwing boss portion 112c formed on the heat sink portion 84 and the rubber holding portion 82b is set to about 180°.

The support disk 60 is configured by integrally connecting the disk-shaped portion 80, the bearing portion 88, the annular portion 109, the rubber holding portions 82a to 82c, the heat sink portion 84, and the screwing boss portions 112a to 112c. .. In other words, the support board 60 is a single member having the disk-shaped portion 80, the bearing portion 88, the annular portion 109, the rubber holding portions 82a to 82c, the heat sink portion 84, and the screwing boss portions 112a to 112c. The support board 60 having such a configuration can be obtained as, for example, a cast product made of an aluminum alloy. The support board 60 is separated from the inner wall of the casing 14 including the protrusion 34 by a predetermined distance.

Further, the screwing boss portions 62a to 62c (see particularly FIG. 6) provided on the upper half body 20 are inserted into the cylindrical rubber member 110 held by the rubber holding portions 82a to 82c. In other words, the cylindrical rubber member 110 is fitted onto the screwing boss portions 62a to 62c. At this time, the screwing boss portions 62a to 62c are entirely embedded in the cylindrical rubber member 110 (see FIG. 2).

In this state, the connection screw 128 (screw member) is screwed by inserting the washer 127 into the screw holes of the screw boss portions 62a to 62c. With this screwing, the cylindrical rubber member 110 is crushed by the washer 127 in the vertical direction by a predetermined amount. As a result, a part of the cylindrical rubber member 110 is inserted between the head of the connecting screw 128 and the screwing boss portions 62a to 62c (upper half body 20).

A coupler housing 46 that constitutes the coupler portion 40 is positioned and fixed near the outer edge of the disk-shaped portion 80. That is, as shown in FIG. 6 in which the lower half body 18 is omitted from illustration, the coupler housing 46 has leg portions 122 protruding from the main body portion 120 toward the disk-shaped portion 80. A screw hole 124 including a not-shown step portion is formed through the leg portion 122. Then, the fixing screw 126 passed through the screw hole 124 is screwed into a screw hole (not shown) formed in the disk-shaped portion 80, so that the coupler housing 46 is connected to the support plate 60. The head of the fixing screw 126 is dammed by the damming step.

The main body 120 is a hollow body in which an inner chamber (not shown) is formed, and two slits 130a and 130b (see FIGS. 3 and 6) are formed through the lower end surface facing downward. That is, the slits 130a and 130b reach the inner surface facing the inner chamber, starting from the lower end surface.

The coupler housing 46 configured as described above is made of resin and is insulative. The four bus bars 44a to 44d are housed in the inner chamber of the main body 120 as described above. These bus bars 44a to 44d are provided so as to project from the circuit board 42 when the circuit board 42 is manufactured, and pass through the slits 130a and 130b when the circuit board 42 is supported by the support board 60 as described later. Then, it is inserted into the inner chamber of the main body 120.

Here, the circuit board 42 has a substantially semicircular shape having a linear portion 132 and a curved arc portion 134 as shown in FIG. 6, and the linear portion 132 faces the rotating shaft 68 (bearing portion 88) side. In the linear portion 132, a relief portion 136 having a shape that is recessed into a substantially quadrangular shape is formed toward the curved arc portion 134 in order to avoid interference with the bearing portion 88. That is, the circuit board 42 does not overlap (cover) the rotary shaft 68 or the bearing portion 88 in a plan view and does not surround the rotary shaft 68 or the bearing portion 88.

The circuit board 42 is provided with various electronic components 138 such as a capacitor, a resistor, and a switching element, which constitutes a control circuit. The control circuit performs control such as controlling the rotation speed of the rotary shaft 68.

Energization of the control circuit is performed via the bus bars 44a to 44d provided on the circuit board 42. The busbars 44a project from the linear portion 132 of the circuit board 42 and linearly extend from the respective sides and below of the busbars 44b, and after being bent, they overlap vertically in a plan view. The bus bars 44a and 44b are separated from each other by a predetermined distance. Similarly, the remaining bus bars 44c and 44d are vertically overlapped with each other while being separated by a predetermined distance.

Support screw insertion holes 140 a to 140 c are formed in the circuit board 42. The support screw 114 is passed through each of the support screw insertion holes 140a to 140c, and each support screw 114 is screwed into each screw hole of the screwing boss portions 112a to 112c of the support board 60. By this screwing, the circuit board 42 is supported by the support board 60. The circuit board 42 is indirectly supported by the casing 14 via the support board 60, but is not directly connected to the casing 14.

As shown in FIGS. 2 and 6 and in FIG. 7 in which the upper half body 20 is omitted, the brushless motor 12 includes a stator 70 that is positioned and fixed to a bearing portion 88, and a rotating shaft 68 that is attached to the rotating shaft 68. And a rotor 72 that rotates with 68. Among them, the stator 70 includes a laminated core 141 having a yoke portion and a tooth portion, a pair of insulators 142a and 142b that sandwich the laminated core 141 from above and below, and teeth of the laminated core 141 via the insulators 142a and 142b. And an electromagnetic coil 143 wound around the section.

The yoke portion forming the laminated core 141 has an annular shape on the inner peripheral side of the laminated core 141. On the other hand, the teeth portion radially protrudes outward in the diametrical direction so as to form a substantially T-shape from the yoke portion. The teeth portion faces the inner peripheral wall (side wall portion 150) of the rotary disk 144 that constitutes the rotor 72. That is, in this case, the brushless motor 12 is a so-called outer rotor type in which the rotor 72 is located outside the stator 70. Since such a configuration is well known, detailed illustration and description thereof will be omitted.

The annular yoke portion forming the laminated core 141 is press-fitted into the press-fitting recess 108 formed on the outer peripheral wall of the bearing portion 88. With this press-fitting, the stator 70 is firmly positioned and fixed.

On the other hand, adjacent teeth portions (electromagnetic coils 143) are separated from each other at a predetermined interval. That is, a clearance is formed between them. This clearance serves as a passage for the cooling air to pass through.

The rotor 72 has a cup-shaped rotary disk 144 supported by a rotary shaft 68 rotatably inserted in a bearing 88 of the support disk 60. The turntable 144 has a cup shape, its circular bottom surface 146 faces upward, and the circular bottom surface 146 rotates from a rotary shaft insertion port 66 formed in the annular projection 64 of the upper half 20. It is exposed with the shaft 68. A slight clearance is formed between the annular protrusion 64 and the circular bottom surface 146. Further, on the circular bottom surface 146, a plurality of substantially trapezoidal ventilation holes 148 facing the teeth portion (electromagnetic coil 143) are formed.

The side wall portion 150 bent so as to substantially hang down from the circular bottom surface 146 has its lower end portion inserted into the annular portion 109 of the support board 60. A plurality of permanent magnets 152 are supported on the inner surface of the side wall 150 so as to face the teeth of the stator 70. When the rotary disk 144 rotates together with the rotary shaft 68, the permanent magnet 152 also rotates integrally with the rotary disk 144.

The air conditioning blower motor unit 10 according to the present embodiment is basically configured as described above. Next, its function and effect will be described.

When the circuit board 42 is attached to the support board 60 to assemble the air conditioning blower motor unit 10, for example, first, the annular yoke portion of the stator 70 is inserted into the press-fitting recess 108 formed in the bearing portion 88 of the support board 60. Press in the center end of the. Further, the rotary shaft 68 is inserted into the bearing portion 88, and each of the first bearing 104 and the second bearing 106 is fitted onto the rotary shaft 68.

At this time, the first bearing 104 is slidably inserted into the first bearing accommodating portion 94 from below the bearing portion 88 with the web washer 105 interposed. The second bearing 106 is press-fitted into the second bearing housing portion 100 from above the bearing portion 88. As described above, the bearing pressure is applied to the first bearing 104 and the second bearing 106.

Next, the rotary disk 144 is press-fitted and fixed from above the rotary shaft 68. As a result, the permanent magnets 152, which are supported by the inner surface of the side wall portion 150 of the rotary disk 144 and constitute the rotor 72, face the laminated core 141 of the stator 70.

Here, the second bearing accommodating portion 100 has large elasticity as described above. Therefore, when the second bearing 106 is press-fitted, it is easily expanded. Therefore, the press-fitting work is easy. Moreover, after the press-fitting, the second bearing accommodating portion 100 tries to return to the shape before the press-fitting, so that the second bearing 106 is elastically urged toward the rotating shaft 68. As a result, the inner ring of the second bearing 106 presses the outer peripheral wall of the rotating shaft 68 substantially uniformly. Therefore, the shaft centers of the rotary shaft 68 and the bearing portion 88 are accurately aligned with each other.

As described above, when the second bearing 106 is press-fitted, the second bearing housing portion 100 expands, but the expanded inner diameter portion 98 does not expand much. Therefore, the press-fitting recess 108 formed on the outer peripheral wall of the expanded inner diameter portion 98 and the laminated core 141 (stator 70) press-fitted into the press-fitting recess 108 are unlikely to be affected. That is, in the present embodiment, although the second bearing accommodating portion 100 is configured to facilitate accommodating the second bearing 106, the second bearing accommodating portion 100 and the expanded inner diameter portion 98 are By offsetting along the axial direction of the portion 88, it becomes easy to press the laminated core 141 into the press-fitting recess 108.

A dihedral angle 92 is provided on the spoke portion 90 of the support board 60. That is, a part of the spoke portion 90 is bent toward the upper half body 20, and a gap is formed below the dihedral angle 92 by this amount. The electronic component 138 provided on the circuit board 42 has entered this gap. Therefore, the so-called dead space between the support board 60 and the circuit board 42 can be reduced, and the distance between the support board 60 and the circuit board 42 can be reduced.

Next, the coupler housing 46 forming the coupler unit 40 is connected to the support board 60. For this purpose, a fixing screw 126 is passed through a screw hole 124 formed in the leg 122, and the fixing screw 126 is screwed into a screw hole for a fixing screw formed in the disc-shaped portion 80 of the support board 60. do it. The screwing of the fixing screw 126 is stopped when the fixing screw 126 is dammed by the damming step portion of the screw hole 124.

Next, the bus bars 44 a to 44 d projecting from the linear portion 132 of the circuit board 42 are passed through the slits 130 a and 130 b formed in the lower end surface of the coupler housing 46 and housed in the inner chamber. Since the bus bars 44a and 44b and the bus bars 44c and 44d vertically overlap each other in a plan view, the bus bars 44a and 44b pass through the slit 130a and the bus bars 44c and 44d pass through the slit 130b. As described above, according to the present embodiment, the bus bars 44a to 44d can be easily accommodated in the coupler housing 46 supported by the support board 60. That is, it is easy to configure the coupler unit 40.

Moreover, since the coupler housing 46 is provided on the support board 60, a sufficient mounting space for the electronic component 138 on the circuit board 42 is ensured. Therefore, a so-called dead space does not easily occur in the circuit board 42. In addition, the coupler section 40 does not overlap the rotating shaft 68 in a plan view. Combined with the above point and the fact that the distance between the support board 60 and the circuit board 42 can be reduced, the circuit board 42 and the air conditioning blower motor unit 10 can be downsized.

Further, since the coupler portion 40 is adjacent to the lower half body 18, it is within the range of the thickness of the lower half body 18. Therefore, the casing 14 is prevented from becoming large in the thickness direction.

On the other hand, the support screw 114 passed through each of the support screw insertion holes 140a to 140c of the circuit board 42 is screwed into the screw holes formed in each of the screwing boss portions 112a to 112c. As a result, the circuit board 42 is supported by the support board 60 via the support screws 114.

The assembly of the brushless motor 12, the circuit board 42 and the support board 60 obtained as described above is assembled to the upper half body 20. That is, the screwing boss portions 62a to 62c provided in the upper half body 20 are inserted into the hollow inside of the cylindrical rubber member 110 previously held by the substantially C-shaped rubber holding portions 82a to 82c. As a result, the cylindrical rubber member 110 is externally fitted to the screwing boss portions 62a to 62c, and the entire screwing boss portions 62a to 62c are embedded in the cylindrical rubber member 110 (see FIG. 2). At the same time, the rotary shaft 68 and the circular bottom surface 146 of the rotary disc 144 are exposed from the rotary shaft insertion opening 66 of the upper half body 20.

Then, the connecting screw 128 is screwed into the screw holes of the screwing boss portions 62a to 62c. Along with this, the cylindrical rubber member 110 is crushed by the head of the connecting screw 128, and the crushed portion is between the head of the connecting screw 128 and the screwing boss portions 62a to 62c (upper half body 20). Intervene in.

Therefore, between the head of the connecting screw 128 and the screwing boss portions 62a to 62c (upper half body 20), the elastic cylindrical rubber member 110 is inserted while sandwiching the rubber holding portions 82a to 82c. It will be in a state of being. Other than this, no structure is particularly provided to support the support board 60. Therefore, the support board 60 is in a state of being floatingly supported by the upper half body 20 (casing 14) under the elastic action of the cylindrical rubber member 110. The circuit board 42 is indirectly supported by the upper half body 20 via the support board 60 and is not directly connected to the upper half body 20.

Next, a connecting screw is passed through each of the screw insertion holes 32a to 32c formed in the lower half body 18, and the connecting screw is screwed into the screw holes 58a to 58c formed in the upper half body 20. .. As a result, the lower half body 18 and the upper half body 20 are connected to each other, and the casing 14 that houses the assembly (the circuit board 42, the support board 60, and the brushless motor 12) is configured. Further, the blower fan 16 (see FIG. 2) is attached to the rotary shaft 68, whereby the air conditioning blower motor unit 10 is obtained.

As described above, since the circuit board 42 is at the offset position where it does not overlap the rotary shaft 68 (or the bearing portion 88) in a plan view, it is possible to avoid an increase in the vertical dimension (thickness direction) of the casing 14. This also facilitates downsizing of the air conditioning blower motor unit 10.

The air conditioning blower motor unit 10 is mounted on a vehicle body and incorporated in a vehicle air conditioning device. At this time, a fixing screw is passed through the stay portions 56a to 56c, and the fixing screw is screwed into a predetermined member, for example, a so-called scroll-shaped fan casing (not shown) surrounding the blower fan 16. Further, the harness on the vehicle body side is electrically connected to the coupler section 40. At this time, since the harness side coupler housing is inserted into the coupler housing 46, the slits 130a and 130b are closed by the harness side coupler housing. Therefore, the bus bars 44a to 44d are prevented from being exposed from the coupler housing 46.

When the vehicle air conditioner is operated, the harness is energized to the control circuit via the bus bars 44a to 44d. Further, under the control of the control circuit, the electromagnetic coil 143 is also energized via various electronic parts 138 such as a capacitor, a resistor and a switching element, and an alternating magnetic field is generated in the stator 70. The turntable 144 rotates due to continuous attraction and repulsion between this alternating magnetic field and the magnetic field generated by the permanent magnets 152 that form the rotor 72. The rotary shaft 68 and the blower fan 16 rotate integrally with this.

Further, as the control circuit is energized, the electronic component 138 and the circuit board 42 are heated. This heat is transmitted to the support board 60 and reaches the heat sink portion 84 of the support board 60. Here, the vicinity of the heat sink portion 84 is in close contact with the circuit board 42 by the support screw 114 screwed to the screwing boss portion 112c. Therefore, the heat of the circuit board 42 is quickly transmitted to the heat sink portion 84 via the screwing boss portion 112c.

Since the blower fan 16 rotates, the air around the blower fan 16 (particularly above) is entrained in the fan casing (not shown), and becomes an air flow toward the centrifugal direction of the blower fan 16 which is a centrifugal fan. A part of this air flow is introduced into the inside of the casing 14 through the air introduction port 22 formed in the tubular portion 50 of the upper half body 20, and becomes a cooling air flowing through the flow passage in the casing 14.

Here, the lower half body 18 is provided with a protrusion 34 (guide portion) that is convex toward the upper half body 20. When the cooling air comes into contact with the protrusion 34, the cooling air flows along the inclined upstream side portion. As a result, the traveling direction of part of the cooling air is changed to the upper half body 20 side. In other words, the protrusion 34 guides part of the cooling air to the upper half 20 side.

A part of the cooling air that has traveled to the upper half 20 side contacts the heat sink portion 84. Therefore, the heat sink portion 84 is quickly cooled. As described above, since the heat of the circuit board 42 is quickly transmitted to the heat sink portion 84, the heat of the circuit board 42 is efficiently dissipated through the heat sink portion 84. As described above, by providing the protrusion 34 (guide portion) in the casing 14 to direct the cooling air to the heat sink portion 84, it becomes easy to remove the heat of the circuit board 42.

Moreover, the heat sink portion 84 is integrally provided as a part of the support board 60. Therefore, the heat radiation area can be increased as compared with the case where a heat sink, which is a separate member, is connected, so that the circuit board 42 can be efficiently cooled while the air conditioning blower motor unit 10 is downsized.

A part of the heat transferred to the support board 60 reaches the bearing portion 88. Therefore, since the bearing 88 is heated, the internal clearance between the first bearing 104 and the second bearing 106 is reduced. This reduces rattling of the first bearing 104 and the second bearing 106 even when the outside air temperature is low. Moreover, the low temperature curing of the grease previously filled in the first bearing 104 and the second bearing 106 is also reduced. Therefore, the rotations of the first bearing 104 and the second bearing 106 are smooth, and the rotation shaft 68 is prevented from rotating while being eccentric, so that the vibration of the rotation shaft 68 is suppressed. As a result, quietness is improved.

The remaining part of the cooling air flows over the protrusion 34, flows through the lower half body 18 (flow passage), and rises toward the circuit board 42 and the electromagnetic coil 143 side. The cooling air passes through the ventilation holes 86 of the support board 60 after coming into contact with the circuit board 42 and the bearing portion 88, and further passes through the gap between the adjacent laminated cores 141. As a result, the circuit board 42, the support board 60, and the brushless motor 12 are cooled.

The cooling air is discharged to the outside of the casing 14 through a gap between the rotary shaft insertion opening 66 of the upper half body 20 and the rotary disk 144 of the brushless motor 12 or a ventilation hole 148 formed in the rotary disk 144. After that, the air is returned to the air flow of the blower fan 16 (centrifugal fan).

The rubber holding portions 82a to 82c project from the outer peripheral edge portion of the disk-shaped portion 80, and in particular, the rubber holding portion 82b is located at a position having a phase difference of 180° with respect to the screwing boss portion 112c of the heat sink portion 84. It is provided. Therefore, the rubber holding portions 82a to 82c are not located in the circulation path of the cooling air. Therefore, in the process in which the cooling air flows as described above, the rubber holding portions 82a to 82c rarely come into contact with each other. That is, the rubber holding portions 82a to 82c do not hinder the circulation of the cooling air.

Vibration is transmitted to the bearing portion 88 as the rotating shaft 68 rotates. Here, the bearing portion 88 has a minimum inner diameter portion 96 in which the spoke portions 90 are continuous. The smallest inner diameter portion 96 is the thickest in the portion forming the bearing portion 88 so that the inner peripheral wall of the smallest inner diameter portion 96 is closer to the side peripheral wall of the rotating shaft 68 than the inner peripheral walls of other portions. Formed in meat. Moreover, in particular, the second bearing 106 receives the elastic force from the second bearing housing portion 100 as described above, so that the side peripheral wall of the rotary shaft 68 is pressed substantially evenly along the circumferential direction. For the above reasons, the rotary shaft 68 is less likely to tilt, and this also prevents the rotary shaft 68 from rotating while causing eccentricity. Therefore, the vibration and the vibration sound are reduced, and the quietness is excellent.

Even if the vibration is transmitted from the bearing portion 88 to the disk-shaped portion 80, since the support board 60 is made of metal and has high rigidity, the support board 60 is unlikely to resonate. Moreover, the cylindrical rubber member 110 is inserted between the rubber holding portions 82a to 82c connected to the disk-shaped portion 80 and the upper half body 20. The cylindrical rubber member 110 exerts a cushioning function against vibration by exhibiting elasticity. In addition, the support board 60 is not directly supported by the casing 14. Therefore, transmission of vibration to the casing 14 is suppressed, and as a result, resonance of the casing 14 is avoided.

Even if the vibration is transmitted to the casing 14, the casing 14 is provided with ribs 36 at portions corresponding to the outer surfaces of the protrusions 34. For this reason, the rigidity of the casing 14 is secured, and the resonance of the casing 14 in the audible range is prevented.

Further, the support board 60 and the circuit board 42 are separated from the inner wall of the casing 14 including the protrusion 34 by a predetermined distance. Therefore, even if the support board 60 and the circuit board 42 that are floatingly supported vibrate or swing, it is possible to avoid the protrusions 34 and other inner walls from interfering with the support board 60 or the circuit board 42. .. From the above reasons, the quietness is further improved. Further, the concern that a contact noise is generated and the concern that the circuit board 42 is scratched are eliminated, and the durability is improved.

After all, according to the present embodiment, it is possible to configure the air conditioning blower motor unit 10 that is excellent in quietness and heat dissipation and is small.

The present invention is not particularly limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

For example, the protrusion 34 is not limited to the one formed by bending the wall portion of the lower half body 18. Another example is a solid protrusion provided in the lower half 18 so as to be raised. In this case, since the outer wall of the lower half body 18 is flat, it is not particularly necessary to provide the rib 36 on the portion corresponding to the outer surface of the protrusion 34.

Further, in this embodiment, the rubber holding portions 82a to 82c holding the cylindrical rubber member 110 have a substantially C shape, but the present invention is not limited to this. For example, the rubber holding portions 82a to 82c may have a substantially U shape. In this case, since it is substantially U-shaped, it becomes easier to insert the cylindrical rubber member 110 into the rubber holding portions 82a to 82c.

DESCRIPTION OF SYMBOLS 10... Air-conditioning blower motor unit 12... Brushless motor 14... Casing 16... Blower fan 18... Lower half 20... Upper half 22... Air inlet 34... Projection 36... Rib 40... Coupler 42... Circuit board 44a- 44d... Bus bar 46... Coupler housing 60... Supporting boards 62a to 62c... Screwing boss portion 66... Rotating shaft insertion port 68... Rotating shaft 70... Stator 72... Rotor 80... Disk shaped portions 82a to 82c... Rubber holding portion 84... Heat sink Portion 86... Vent hole 88... Bearing portion 90... Spoke portion 92... Dihedral angle 94... First bearing housing portion 96... Minimum inner diameter portion 98... Expanded inner diameter portion 100... Second bearing housing portion 104... First bearing 106... Second bearing 108... Press-fitting concave portion 110... Cylindrical rubber members 112a to 112c... Screwing boss portion 114... Support screw 120... Main body portion 122... Leg portion 128... Connecting screw 130a, 130b... Slit 132... Straight portion 134... Curved arc portion 136... Escape portion 138... Electronic components 140a to 140c... Support screw insertion hole 143... Electromagnetic coil 144... Rotating plate 148... Ventilation port 152... Permanent magnet

Claims (5)

A brushless motor for rotating a blower fan that constitutes an air conditioner,
A circuit board provided with a control circuit for controlling the brushless motor,
A support board that has a bearing portion that rotatably supports the rotation shaft of the brushless motor, and that supports the circuit board at an offset position where the circuit board does not overlap the bearing portion in plan view,
A casing that is configured by combining a first casing member and a second casing member, and that houses the brushless motor, the circuit board, and the support board;
Equipped with
The support board has a first surface facing the first casing member and a second surface facing the second casing member,
The circuit board is held on the second surface side of the support board,
On the first surface side of the support board, a heat dissipation portion capable of radiating heat of the circuit board is integrally formed with the support board,
In the first casing member, an air introduction port, a rotation shaft insertion port through which the rotation shaft is passed, and a part of the air introduced from the air introduction port are passed through the heat dissipation unit and the brushless motor. A first flow passage is formed to circulate in the rotary shaft insertion opening ,
A second flow passage is formed in the second casing member for circulating the air introduced from the air introduction port, and the air is guided from the second flow passage to the first casing member side. The guide section of
The guide portion is Ri protruding projection der to form a substantially inverted V-shape oriented in the first casing member,
A clearance is formed between the protrusion and the circuit board,
Beyond the remainder of the air is the projection, from the clearance, the circuit for air conditioning blower motor unit substrate and through between the second casing member, wherein that you flow to said rotary shaft insertion hole. 2. The unit according to claim 1 , wherein the guide portion is a solid protrusion that is provided inside the second casing member so as to bulge toward the first casing member side and has a triangular shape in a sectional view. A blower motor unit for air conditioning characterized by the following. 2. The unit according to claim 1 , wherein the guide portion is a protrusion having a shape in which an outer wall of the second casing member is bent toward the first casing member side, and corresponds to an outer surface of the guide portion. A blower motor unit for air conditioning, characterized in that a rib is provided on the part. In unit according to any one of claims 1 to 3, wherein the support plate is elastically supported on said casing in a state where the buffer member is interposed between the casing and the clearance, the rotation the support plate and the circuit board, the air conditioning blower motor unit, characterized in Oh Rukoto distance that does not interfere with the casing in which the projection is provided when the shaft is rotated. 5. The unit according to claim 4 , wherein the support board has a tongue portion that projects from an outer edge portion of the support board and holds the cushioning member.
The screwing portion provided on the first casing member is passed through the cushioning member held by the tongue piece,
The blower motor unit for air conditioning, wherein the cushioning member is inserted between a head portion of a screwing member screwed into the screwing portion and the screwing portion.

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