Motor bearing structure, motor, and indoor equipment

Abstract

To solve a problem that when an elastic member for holding a plain bearing thermally expands, the plain bearing is compressed by the elastic member, and as a result, the plain bearing may be pressed with excessive force against a member other than the elastic member, resulting in damage.SOLUTION: A first bearing structure 91 comprises a first bearing 91a that supports a first shaft 22c, a stator cover 83b, and an elastic member 92. The stator cover 83b holds a first bearing 91a. The elastic member 92 applies, to the first bearing 91a, first force for pressing the first bearing 91a toward the stator cover 83b in a first direction along the rotation axis of the first shaft 22c. The elastic member 92 has a thermal expansion coefficient larger than that of the first bearing 91a. The elastic member 92 has a ring-shaped first elastic portion 92a and a plurality of second elastic portions 92b. The plurality of second elastic portions 92b are provided around the rotation axis at intervals along a second direction in which the first shaft 22c rotates when viewed from the first direction.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present disclosure relates to a bearing structure of a motor, a motor, and an indoor unit. [Background technology]

[0002] As disclosed in Patent Document 1 (JP 2011-89533 A), there is a known bearing structure for a motor in which a sliding bearing for rotatably supporting a shaft is held by a holding member. The holding member is made of a thermosetting resin, a metal, an elastic material, or the like. Summary of the Invention [Problem to be solved by the invention]

[0003] The thermal expansion coefficient of the elastic member, which is a retaining member made of an elastic material, is greater than that of the sliding bearing. Therefore, when the temperature of the motor rises after starting the motor, the thermal expansion of the elastic member causes the sliding bearing to be compressed by the elastic member. As a result, the sliding bearing is pressed against the retaining member other than the elastic member with excessive force, which may damage the sliding bearing. [Means for solving the problem]

[0004] A bearing structure for a motor according to a first aspect includes a bearing, a first member, and an elastic member. The bearing rotatably supports the shaft. The first member holds the bearing. The elastic member applies a first force to the bearing that presses the bearing toward the first member in a first direction along the rotation axis of the shaft. The elastic member has a thermal expansion coefficient greater than that of the bearing. The elastic member has an annular first elastic portion and a plurality of second elastic portions. The first elastic portion surrounds the shaft when viewed from the first direction. The plurality of second elastic portions are provided around the rotation axis at intervals along a second direction in which the shaft rotates when viewed from the first direction.

[0005] A motor bearing structure according to a first aspect includes an elastic member that applies to the bearing a force pressing the bearing toward the stator. When viewed along the rotation axis of the motor shaft, the elastic member has a plurality of notched portions formed along the circumferential direction. When the elastic member thermally expands, the notched portions can absorb a portion of the increased volume of the elastic member. This prevents the bearing from being damaged by the thermally expanded elastic member pressing the bearing against the stator with excessive force.

[0006] A motor bearing structure of a second aspect is the motor bearing structure of the first aspect, wherein the multiple second elastic portions protrude from the first elastic portion toward the radially outer side of the first elastic portion when viewed from the first direction.

[0007] A motor bearing structure according to a third aspect is the motor bearing structure according to the first or second aspect, in which the second elastic parts have an inner edge extending along the second direction when viewed from the first direction, and an outer edge extending along the second direction and positioned radially outward of the inner edge. The motor bearing structure according to the third aspect satisfies a relational expression of 0.5≦S1 / S2≦0.7. S1 is a total area of ​​a region occupied by the second elastic parts when viewed from the first direction. S2 is an area of ​​a first region between the first closed curve and the second closed curve. The first closed curve is formed by virtually extending and connecting the inner edges of the second elastic parts along the second direction when viewed from the first direction. The second closed curve is formed by virtually extending and connecting the outer edges of the second elastic parts along the second direction when viewed from the first direction.

[0008] A motor bearing structure according to a fourth aspect is the motor bearing structure according to any one of the first to third aspects, further comprising a second member that holds the bearing. The elastic member is disposed between the first member and the second member in the first direction.

[0009] A bearing structure for a motor according to a fourth aspect includes a second member for restricting movement of the elastic member in the axial direction of the shaft, The second member prevents the elastic member from jumping out of the bearing structure for the motor.

[0010] A motor bearing structure according to a fifth aspect is the motor bearing structure according to any one of the first to fourth aspects, wherein the elastic member applies a first force to the bearing via the third member.

[0011] A motor bearing structure according to a fifth aspect of the present invention includes a third member for reducing the contact area between the elastic member and the bearing. The third member suppresses damage to the elastic member.

[0012] A sixth aspect of the present invention relates to a motor bearing structure of the fifth aspect, in which the third member is disposed radially outward of the bearing. The third member is sandwiched between the first member and the elastic member in the first direction and is in contact with the elastic member and the bearing.

[0013] A seventh aspect of the present invention relates to a motor bearing structure according to any one of the first to sixth aspects, in which the bearing is a spherical bearing having a spherical surface. The elastic member applies a first force to at least a part of the spherical surface.

[0014] The motor bearing structure of an eighth aspect is the motor bearing structure of the seventh aspect, in which the bearing has a pair of spherical surfaces, a first spherical surface and a second spherical surface, located on both sides in a first direction. The first member contacts the first spherical surface. The elastic member contacts the second spherical surface.

[0015] A motor bearing structure of a ninth aspect is a motor bearing structure of any one of the first to eighth aspects, wherein the elastic member is arranged such that a portion of the multiple second elastic portions is located vertically below the shaft when the first direction is parallel to the horizontal direction.

[0016] In a ninth aspect, the motor bearing structure is installed such that, when the rotation axis of the shaft is horizontal, the second elastic portion (a portion other than the notch portion) of the elastic member is located vertically below the shaft. Since the elastic member can support the load of the bearing and the shaft, damage to the bearing and the shaft is suppressed.

[0017] A motor according to a tenth aspect includes a stator, a rotor, and a shaft. The rotor is supported rotatably relative to the stator. The shaft is fixed to the rotor. The shaft is supported by the bearing structure of the motor according to any one of the first to ninth aspects.

[0018] An indoor unit according to an eleventh aspect is an indoor unit for an air conditioner, and includes a heat exchanger, a fan, and the motor according to the tenth aspect. The fan passes indoor air through the heat exchanger and sends the air out into the room. The motor drives the fan. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is an external view of an air conditioner 101 according to an embodiment. [Diagram 2] 1 is a schematic diagram of a refrigerant circuit of an air conditioner 101 of an embodiment. [Diagram 3] 2 is a cross-sectional view of the indoor unit 102 of the embodiment as viewed from the right side. [Figure 4] FIG. 2 is a schematic plan view of a blower unit 18 according to the embodiment. [Diagram 5] 5 is a cross-sectional view of the cross flow fan 22 and the indoor fan motor 81 taken along line VV in FIG. [Figure 6] 6 is an enlarged view of the vicinity of the first bearing structure 91 in FIG. 5. FIG. [Figure 7] 2 is a perspective view of each component constituting a first bearing structure 91 of the embodiment. FIG. [Figure 8] FIG. 8 is a perspective view of an elastic member 92 in FIG. [Figure 9] 8 is a plan view of the elastic member 92 of FIG. 7 as viewed along the axial direction. [Figure 10] 8 is a plan view of the elastic member 92 of FIG. 7 as viewed along the axial direction. [Figure 11] FIG. 11 is a perspective view of an elastic member 192 as a comparative example. [Figure 12] 13 is an enlarged view of the vicinity of a first bearing structure 91 of modification C. FIG. [Figure 13] 13 is a plan view of an elastic member 392 of Modification Example D. FIG. [Figure 14] 13 is a side view of an elastic member 392 of Modification Example D. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] --Embodiment-- (1) Overall configuration of air conditioner The bearing structure of the motor in the embodiment of the present disclosure is a first bearing structure 91 of an indoor fan motor 81. The indoor fan motor 81 is used in an indoor unit 102 of an air conditioner 101. As shown in FIG. 1, the air conditioner 101 includes an indoor unit 102 attached to a wall surface or the like in the room, and an outdoor unit 103 installed outside the room. The air conditioner 101 performs cooling operation, heating operation, and the like in the room in which the indoor unit 102 is installed. Hereinafter, the upper side U, lower side D, left side L, right side R, front side F, and rear side B of the indoor unit 102 installed in the room are referred to as the sides indicated by arrows in FIG. 1 and the like. The front side is the side where the air outlet 71 is provided. The left side is the left side when the indoor unit 102 is viewed from the front side.

[0021] The indoor unit 102 and the outdoor unit 103 are connected to each other via a refrigerant pipe 104. The indoor unit 102, the outdoor unit 103, and the refrigerant pipe 104 constitute a refrigerant circuit of the air conditioner 101. As shown in FIG. 2, the refrigerant circuit includes an indoor heat exchanger 21, a crossflow fan 22, a compressor 31, a four-way switching valve 32, an accumulator 33, an outdoor heat exchanger 34, an expansion valve 35, a filter 36, a liquid-side shutoff valve 37, a gas-side shutoff valve 38, and a propeller fan 39. The indoor heat exchanger 21 and the crossflow fan 22 are installed inside the indoor unit 102. The compressor 31, the four-way switching valve 32, the accumulator 33, the outdoor heat exchanger 34, the expansion valve 35, the filter 36, the liquid-side shutoff valve 37, the gas-side shutoff valve 38, and the propeller fan 39 are installed inside the outdoor unit 103. In FIG. 2, the flow of the refrigerant during cooling operation is indicated by solid arrows, and the flow of the refrigerant during heating operation is indicated by dotted arrows.

[0022] The indoor heat exchanger 21 has a heat transfer tube that is folded back multiple times at both ends in the longitudinal direction, and fins attached to the heat transfer tube. The indoor heat exchanger 21 exchanges heat between the refrigerant flowing inside the heat transfer tube and the air passing through the fins. The indoor heat exchanger 21 functions as a heat absorber (evaporator) during cooling operation, cooling the air passing through the fins. The indoor heat exchanger 21 functions as a heat radiator (condenser) during heating operation, heating the air passing through the fins.

[0023] The cross flow fan 22 sends out into the room the air that has undergone heat exchange in the indoor heat exchanger 21. The cross flow fan 22 is driven by an indoor fan motor 81.

[0024] The compressor 31 compresses the gaseous refrigerant sent from the accumulator 33. The refrigerant compressed by the compressor 31 is sent to the outdoor heat exchanger 34 during cooling operation, and is sent to the indoor heat exchanger 21 during heating operation.

[0025] The four-way switching valve 32 switches between a refrigerant circuit during cooling operation and a refrigerant circuit during heating operation.

[0026] The accumulator 33 is connected to the suction side of the compressor 31, and separates the refrigerant into gas and liquid before the refrigerant is sucked into the compressor 31. The accumulator 33 prevents liquid refrigerant from being fed into the compressor 31.

[0027] The outdoor heat exchanger 34 has a heat transfer tube that is folded back multiple times at both ends in the longitudinal direction, and fins attached to the heat transfer tube. The outdoor heat exchanger 34 exchanges heat between the refrigerant flowing inside the heat transfer tube and the air passing through the fins. The outdoor heat exchanger 34 functions as a heat radiator during cooling operation and as a heat absorber during heating operation.

[0028] The expansion valve 35 is provided at a position through which the refrigerant passes after being discharged from the radiator and before being drawn into the heat absorber. The expansion valve 35 reduces the pressure of the high-temperature, high-pressure refrigerant discharged from the radiator to a state in which the refrigerant is easily evaporated in the heat absorber.

[0029] The filter 36 is provided between the expansion valve 35 and the liquid side shutoff valve 37. The filter 36 captures foreign matter contained in the refrigerant flowing through the refrigerant circuit.

[0030] The liquid side shut-off valve 37 and the gas side shut-off valve 38 are used during maintenance work such as replacing the refrigerant in the refrigerant circuit. The liquid side shut-off valve 37 is provided at a position where the refrigerant passes after being discharged from the heat radiator and before being sucked into the heat absorber. The gas side shut-off valve 38 is provided at a position where the refrigerant passes after being discharged from the heat absorber and before being sucked into the heat radiator.

[0031] The propeller fan 39 exhausts the air that has undergone heat exchange in the outdoor heat exchanger 34 from the outdoor unit 103. The propeller fan 39 is driven by an outdoor fan motor 40.

[0032] (2) Indoor unit configuration 1, the indoor unit 102 has a shape that extends laterally (toward both the left and right sides) when viewed from the front. As shown in FIG. 3, the indoor unit 102 has an upper casing 16, a lower casing 17, a blower unit 18, and an indoor heat exchanger 21.

[0033] (2-1) Upper casing The upper casing 16 covers the upper part of the indoor unit 102. An intake port 61 is formed in the upper casing 16. The intake port 61 is formed on the upper side of the indoor unit 102 and on the upper front part of the indoor unit 102. The intake port 61 is an opening that extends in the longitudinal direction (lateral direction) of the indoor unit 102. An indoor heat exchanger 21 is installed below the intake port 61 of the upper casing 16. Indoor air is sucked into the indoor unit 102 through the intake port 61.

[0034] (2-2) Lower casing The lower casing 17 covers the lower part of the indoor unit 102. An air outlet 71 is formed in the lower casing 17. The air outlet 71 is formed in the lower part of the front side of the indoor unit 102. The air outlet 71 is an opening extending in the longitudinal direction of the indoor unit 102. Air that has undergone heat exchange inside the indoor unit 102 is blown out into the room through the air outlet 71.

[0035] A horizontal flap 73 is attached to the air outlet 71. The horizontal flap 73 guides the flow of air blown into the room. The horizontal flap 73 is driven to rotate about an axis along the longitudinal direction of the indoor unit 102 by a flap motor (not shown). The horizontal flap 73 opens and closes the air outlet 71, and changes the direction of the flow of air blown into the room.

[0036] (2-3) Blower unit The blower unit 18 is installed inside the indoor unit 102. The blower unit 18 is attached to the lower casing 17. The blower unit 18 generates a flow of air that passes through the indoor heat exchanger 21 inside the indoor unit 102.

[0037] 4, the blower unit 18 has a cross flow fan 22, an indoor fan motor 81, and an electrical component box 75. The electrical component box 75 is installed on the right side of the indoor unit 102. The indoor fan motor 81 is installed between the cross flow fan 22 and the electrical component box 75. The electrical component box 75 houses a microcomputer and the like for controlling each component of the indoor unit 102.

[0038] (2-4) Indoor heat exchanger The indoor heat exchanger 21 is disposed inside the indoor unit 102 so as to face the blower unit 18. Specifically, as shown in Fig. 3, the indoor heat exchanger 21 is disposed so as to surround the front, rear, and upper sides of the blower unit 18. In the indoor heat exchanger 21, heat exchange is performed between the air sucked in from the suction port 61 by the blower unit 18 and the refrigerant circulating in the refrigerant circuit. The air that has undergone heat exchange in the indoor heat exchanger 21 is blown out from the outlet 71 into the room by the blower unit 18.

[0039] (3) Configuration of crossflow fan and indoor fan motor (3-1) Crossflow fan The crossflow fan 22 has a thin and elongated cylindrical shape extending in the longitudinal direction of the indoor unit 102. The crossflow fan 22 is molded from a plastic such as AS resin. As shown in Figs. 4 and 5, the crossflow fan 22 is arranged so that the rotation axis A1, which is the central axis of the cylindrical shape, is horizontal. Therefore, the rotation axis A1 of the crossflow fan 22 is aligned along the longitudinal direction of the indoor unit 102. The crossflow fan 22 rotates about the rotation axis A1, thereby generating an air flow in a direction intersecting the rotation axis A1. The air flow generated by the crossflow fan 22 draws air in through the inlet 61 and blows air out through the outlet 71.

[0040] The cross flow fan 22 has a first end plate 22a, a second end plate 22b, a first shaft 22c, a second shaft 22d, and a blade portion 22e.

[0041] Wing portion 22e is a cylindrical member. The central axis of the cylindrical shape of wing portion 22e is aligned with rotation axis A1. Wing portion 22e is disposed between first end plate 22a and second end plate 22b in the direction along rotation axis A1. Wing portion 22e rotates about rotation axis A1 to generate an air flow in a direction intersecting rotation axis A1.

[0042] The first end plate 22a is attached to the right end surface of the blade portion 22e. An indoor fan motor 81 is attached to the first end plate 22a. The second end plate 22b is attached to the left end surface of the blade portion 22e.

[0043] The first shaft 22c is coupled to the first end plate 22a and disposed along the rotation axis A1. The first shaft 22c is supported by a first bearing structure 91 of the indoor fan motor 81 so as to be rotatable.

[0044] The second shaft 22d is coupled to the second end plate 22b and disposed along the rotation axis A1. The second shaft 22d is rotatably supported by a second bearing structure 99. The second bearing structure 99 has a second bearing 99a for supporting the second shaft 22d. The second bearing structure 99 is fixed to a casing of the blower unit 18.

[0045] (3-2) Indoor fan motor The indoor fan motor 81 transmits rotational force to the cross flow fan 22 while supporting the first shaft 22c. Specifically, the indoor fan motor 81 drives the cross flow fan 22 to rotate about the rotation axis A1. The indoor fan motor 81 has a rotor 82 and a stator 83. The indoor fan motor 81 is an outer rotor type motor. In other words, the rotor 82 is located outside the stator 83. A gap is formed between the inner circumferential surface of the rotor 82 and the outer circumferential surface of the stator 83.

[0046] The rotor 82 is made of a resin material containing tiny magnetic particles. The rotor 82 rotates by the magnetic force generated by the stator 83. The rotor 82 is attached to the first end plate 22a of the cross flow fan 22. Therefore, the rotation of the rotor 82 causes the cross flow fan 22 to rotate about the rotation axis A1.

[0047] The stator 83 has a stator core 83a and a stator cover 83b. The stator core 83a is a cylindrical member composed of an iron core, a coil, and the like for generating a magnetic field that rotates the rotor 82. The stator cover 83b covers a part of the outer circumferential surface of the stator core 83a. The stator cover 83b is molded from an unsaturated polyester resin such as BMC (Bulk Molding Compound). As shown in FIG. 5, the stator core 83a has a through hole formed along the central axis of the cylindrical shape. The stator cover 83b covers the inner circumferential surface of the through hole of the stator core 83a.

[0048] Stator 83 is supported by a stator housing (not shown) and is fixed to the casing of blower unit 18. The stator housing has a shape capable of accommodating stator 83, and covers the right end face of stator 83. Stator 83 may be supported by the stator housing via a vibration-proof member. In this case, the vibration-proof member is made of rubber or the like, and has the function of absorbing vibrations of indoor fan motor 81.

[0049] (3-3) First bearing structure The indoor fan motor 81 has a first bearing structure 91 for supporting the first shaft 22c of the cross flow fan 22. The first bearing structure 91 is provided inside the stator 83.

[0050] 6 and 7, the first bearing structure 91 has a first bearing 91a, an elastic member 92, a metal cap 93, and a resin cap 94. In the following, the axial direction means the axial direction of the first shaft 22c, in other words, the direction along the rotation axis A1 of the crossflow fan 22 (first direction). The radial direction means the radial direction of the first shaft 22c, in other words, the direction perpendicular to the rotation axis A1 of the crossflow fan 22. The circumferential direction means the direction in which the first shaft 22c rotates, in other words, the direction going around the rotation axis A1 in a plane perpendicular to the rotation axis A1 of the crossflow fan 22 (second direction).

[0051] The first bearing 91a, the elastic member 92, the metal cap 93, and the resin cap 94 are housed inside a bearing hole 96 that penetrates the stator 83 in the axial direction. The elastic member 92, the metal cap 93, and the resin cap 94 are members for holding the first bearing 91a inside the bearing hole 96. The inner peripheral surface of the bearing hole 96 corresponds to the surface of the stator cover 83b that covers the inner peripheral surface of the through hole of the stator core 83a. The inner peripheral surface of the bearing hole 96 includes a first support surface 96a, a second support surface 96b, and a third support surface 96c. The first support surface 96a is curved along the axial direction. The second support surface 96b and the third support surface 96c are parallel to the radial direction. In the axial direction, the second support surface 96b is located farther away from the cross flow fan 22 than the first support surface 96a. In the axial direction, the third support surface 96c is located farther from the cross flow fan 22 than the second support surface 96b.

[0052] The first bearing 91a rotatably supports the first shaft 22c. The first bearing 91a is molded from an engineering plastic such as POM (Polyoxymethylene). The first bearing 91a is a spherical bearing, which is a type of self-aligning plain bearing. As shown in FIG. 6 and FIG. 7, the first bearing 91a has a first spherical surface 95a and a second spherical surface 95b. The first spherical surface 95a and the second spherical surface 95b are a pair of spherical surfaces located on both sides of the first bearing 91a in the axial direction. As shown in FIG. 6, the first spherical surface 95a contacts the first support surface 96a of the stator cover 83b. The second spherical surface 95b contacts the elastic member 92 and the resin cap 94. The first bearing 91a has a cylindrical through hole through which the first shaft 22c passes. The first bearing 91a is arranged so that the central axis of the through hole is aligned with the axial direction.

[0053] The resin cap 94 is disposed radially outside the first bearing 91a. The resin cap 94 is an annular member located between the stator cover 83b and the elastic member 92 in the axial direction. The resin cap 94 is molded from an engineering plastic such as POM. One end face (axial end face) of the resin cap 94 contacts the second support surface 96b of the stator cover 83b in the axial direction. The other end face of the resin cap 94 contacts the end face of the elastic member 92 in the axial direction. The inner peripheral surface of the resin cap 94 contacts the side surface of the first bearing 91a. A part of the inner peripheral surface of the resin cap 94 contacts the second spherical surface 95b of the first bearing 91a.

[0054] The metal cap 93 is an annular member attached to the end of the bearing hole 96. The metal cap 93 is located on the opposite side of the cross-flow fan 22 in the axial direction. The metal cap 93 is molded from a metal such as stainless steel. The metal cap 93 is fixed to the stator cover 83b by press-fitting. As shown in FIG. 7, the metal cap 93 has an annular portion 93a, a wall portion 93b, and an inclined portion 93c. The wall portion 93b is a portion that rises from the entire outer periphery of the annular portion 93a toward the right side. The inclined portion 93c is a portion that rises from the entire inner periphery of the annular portion 93a toward the right side. The inclined portion 93c is inclined so as to approach the radial inside as it moves away from the annular portion 93a. The outer periphery of the annular portion 93a and the wall portion 93b contact the inner periphery of the bearing hole 96. The outer periphery of the annular portion 93a contacts the third support surface 96c of the stator cover 83b.

[0055] The elastic member 92 is located between the stator cover 83b and the metal cap 93 in the axial direction. The elastic member 92 is located between the resin cap 94 and the metal cap 93 in the axial direction. The elastic member 92 is molded from, for example, silicone rubber. The thermal expansion coefficient (linear expansion coefficient) of the elastic member 92 is greater than the thermal expansion coefficient of the first bearing 91a. One end face of the elastic member 92 contacts an end face of the resin cap 94 in the axial direction. The other end face of the elastic member 92 contacts an inner peripheral portion of the annular portion 93a of the metal cap 93 and an inclined portion 93c of the metal cap 93 in the axial direction. The elastic member 92 is provided in a state compressed in the axial direction to such an extent that an elastic force is generated in the axial direction.

[0056] As shown in FIG. 8, the elastic member 92 has an annular first elastic portion 92a, a plurality of second elastic portions 92b, and an annular third elastic portion 92c. When viewed from the axial direction, the first elastic portion 92a surrounds the first shaft 22c. When viewed from the axial direction, the plurality of second elastic portions 92b are provided at intervals along the circumferential direction. When viewed from the axial direction, the plurality of second elastic portions 92b protrude radially outward from the side surface of the first elastic portion 92a. The second elastic portion 92b has an end surface that contacts the inner peripheral portion of the annular portion 93a of the metal cap 93. The third elastic portion 92c protrudes in the axial direction from the end surface of the first elastic portion 92a. The third elastic portion 92c has an inclined surface that contacts the inner peripheral surface of the inclined portion 93c of the metal cap 93.

[0057] As shown in Figs. 9 and 10, in this embodiment, the elastic member 92 has three second elastic portions 92b. All three second elastic portions 92b have the same shape and dimensions. When viewed from the axial direction, the three second elastic portions 92b are provided at positions that are equally spaced apart in the circumferential direction. Therefore, as shown in Figs. 9 and 10, when viewed from the axial direction, a notch portion 92d is formed between two second elastic portions 92b that are adjacent to each other in the circumferential direction. The number of notches 92d is the same as the number of second elastic portions 92b. All three notches 92d have the same shape and dimensions.

[0058] When viewed from the axial direction, the second elastic portion 92b has an inner edge E1 and an outer edge E2 that are arc-shaped and extend along the circumferential direction. The inner edge E1 and the outer edge E2 are indicated by thick lines in Fig. 9. The outer edge E2 is located radially outward of the inner edge E1.

[0059] In FIG. 10, the first closed curve C1 and the second closed curve C2 are indicated by thick lines. When viewed from the axial direction, the first closed curve C1 is formed by virtually extending and connecting the inner edges E1 of all the second elastic parts 92b along the circumferential direction. When viewed from the axial direction, the second closed curve C2 is formed by virtually extending and connecting the outer edges E2 of all the second elastic parts 92b along the circumferential direction. When viewed from the axial direction, the first closed curve C1 and the second closed curve C2 are concentric circles centered on the rotation axis A1. The first region R1 is an annular region between the first closed curve C1 and the second closed curve C2.

[0060] The second elastic parts 92b of the elastic member 92 have a shape and dimensions that satisfy the relational expression 0.5≦S1 / S2≦0.7. S1 is the total area of ​​the area occupied by all the second elastic parts 92b when viewed from the axial direction. S2 is the area of ​​the first region R1 when viewed from the axial direction. In FIG. 9, the area occupied by all the second elastic parts 92b (area having the total area S1) when viewed from the axial direction is shown as a hatched area. In FIG. 10, the first region R1 (area having the area S2) is shown as a hatched area.

[0061] The above relational expression means that the second elastic portions 92b occupy 50% to 70% of the first region R1 when viewed from the axial direction. In other words, the above relational expression means that the cutout portions 92d occupy 30% to 50% of the first region R1 when viewed from the axial direction.

[0062] (4) Features (4-1) The first bearing structure 91 has an elastic member 92. The elastic member 92 applies a first force to the first bearing 91a, which presses the first bearing 91a toward the stator cover 83b in the axial direction. As shown in Fig. 6, the first bearing 91a receives the first force from the elastic member 92 and is pressed toward the first support surface 96a. The first force is caused by the elastic force of the elastic member 92.

[0063] FIG. 11 shows an elastic member 192 as a comparative example. The elastic member 192 has a first elastic portion 192a, a second elastic portion 192b, and a third elastic portion 192c. The first elastic portion 192a and the third elastic portion 192c have the same shape and dimensions as the first elastic portion 92a and the third elastic portion 92c of the embodiment, respectively. When viewed from the axial direction, the second elastic portion 192b is an annular member that protrudes radially outward from the entire side surface of the first elastic portion 192a. Therefore, the elastic member 192 does not have elements corresponding to the multiple second elastic portions 92b and multiple cutout portions 92d of the embodiment.

[0064] When the first bearing structure 91 has the elastic member 192, the following problem may occur. When the stator 83 heats up during operation of the indoor fan motor 81 and the temperature of the first bearing structure 91 rises, the volume of the elastic member 192 increases due to thermal expansion of the elastic member 192. Therefore, the elastic member 192 is compressed, and the magnitude of the elastic force of the elastic member 192 increases, and as a result, the magnitude of the first force increases. This may cause the elastic member 192 to press the first bearing 91a toward the stator cover 83b with excessive force, which may damage the first bearing 91a.

[0065] In this embodiment, the elastic member 92 has a plurality of second elastic parts 92b and a plurality of cutout parts 92d formed along the circumferential direction. The cutout parts 92d can absorb a part of the increased volume of the elastic member 92 when the elastic member 92 thermally expands. Specifically, when the elastic member 92 thermally expands, the second elastic parts 92b expand in the circumferential direction, thereby suppressing the axial expansion of the elastic member 92. As a result, the elastic member 92 of this embodiment suppresses an increase in the magnitude of the first force when thermally expanding, compared to the elastic member 192 of FIG. 11. Therefore, in the first bearing structure 91, damage to the first bearing 91a caused by the thermal expansion of the elastic member 92 is suppressed.

[0066] (4-2) The first bearing structure 91 has a metal cap 93. The metal cap 93 limits movement of the elastic member 92 in the axial direction. Therefore, in the first bearing structure 91, the metal cap 93 prevents the elastic member 92 from jumping out of the bearing hole 96 in the axial direction.

[0067] (4-3) The first bearing structure 91 has a resin cap 94. The resin cap 94 reduces the contact area between the elastic member 92 and the first bearing 91a. Therefore, in the first bearing structure 91, the resin cap 94 suppresses damage to the elastic member 92 caused by sliding between the elastic member 92 and the first bearing 91a.

[0068] --Variations-- (1) Variation A In the embodiment, the first bearing structure 91 is disposed so that the axial direction is parallel to the horizontal direction. In this case, it is preferable that the elastic member 92 is disposed so that some of the multiple second elastic portions 92b are positioned vertically below the first shaft 22c. This allows the elastic member 92 to support the load of the first bearing 91a and the first shaft 22c by the second elastic portions 92b positioned vertically below the first shaft 22c. Therefore, damage to the first bearing 91a and the first shaft 22c caused by sliding between the first bearing 91a and the first shaft 22c is suppressed.

[0069] The shape, dimensions and material of the second elastic portion 92b are preferably set so that the elastic member 92 can sustain a stress equivalent to half the weight of the cross flow fan 22 when the elastic member 92 is not thermally expanded.

[0070] (2) Variation B In the embodiment, the elastic member 92 has three second elastic portions 92b. However, the number of second elastic portions 92b may be any number. For example, the elastic member 92 may have four to six second elastic portions 92b. When viewed in the axial direction, the multiple second elastic portions 92b are preferably provided at positions that are equally spaced in the circumferential direction.

[0071] (3) Variation C In the embodiment, the first bearing structure 91 has a resin cap 94. However, the first bearing structure 91 does not have to have the resin cap 94. Specifically, as shown in FIG. 12, the first bearing structure 91 may have an elastic member 292 having a longer axial dimension than the elastic member 92 of the embodiment. The elastic member 292 has portions corresponding to the plurality of second elastic portions 92b of the embodiment. Also, as shown in FIG. 12, a space may be provided between an end face of the elastic member 292 on the cross flow fan 22 side and the second support surface 96b of the stator cover 83b.

[0072] Modifications A and B are applicable to this modification.

[0073] (4) Variation D In the embodiment, the elastic member 92 has a shape in which a plurality of second elastic portions 92b protrude radially outward from the side surface of the first elastic portion 92a. However, the elastic member 92 may have another shape. For example, the first bearing structure 91 may have an elastic member 392 shown in Figs. 13 and 14. Fig. 13 is a plan view of the elastic member 392 as viewed from the opposite side to Fig. 9 in the axial direction. Fig. 14 is a side view of the elastic member 392 as viewed from the radial direction.

[0074] The elastic member 392 has an annular first elastic portion 392a, a plurality of second elastic portions 392b, and an annular third elastic portion 392c. The first elastic portion 392a and the third elastic portion 392c have the same shape and dimensions as the first elastic portion 92a and the third elastic portion 92c of the embodiment, respectively. The plurality of second elastic portions 392b protrude in the axial direction from an axial end face 392e of the first elastic portion 392a. When viewed from the axial direction, the plurality of second elastic portions 392b are provided at intervals along the circumferential direction, similar to the second elastic portion 92b of the embodiment. An axial end face 392f of the plurality of second elastic portions 392b contacts the first bearing 91a.

[0075] In this modification, as in the embodiment, a notch 392d is formed between two second elastic portions 392b adjacent to each other in the circumferential direction when viewed from the axial direction. The notch 392d can absorb a part of the increased volume of the elastic member 392 when the elastic member 392 thermally expands. Therefore, in the first bearing structure 91 having the elastic member 392, damage to the first bearing 91a caused by thermal expansion of the elastic member 392 is suppressed.

[0076] Modifications A to C are applicable to this modification.

[0077] -Conclusion- Although the embodiments of the present disclosure have been described above, it will be understood that various changes in form and details can be made without departing from the spirit and scope of the present disclosure described in the claims. [Explanation of symbols]

[0078] 21: Indoor heat exchanger (heat exchanger) 22: Crossflow fan (fan) 22c: 1st shaft (shaft) 81: Indoor fan motor (motor) 82: Rotor 83: Stator 83b: Stator cover (first member) 91: First bearing structure (motor bearing structure) 91a: First bearing (bearing) 92: Elastic material 92a: First elastic part 92b: second elastic part 93: Metal cap (second component) 94: Resin cap (third component) 95a: 1st spherical surface (spherical surface) 95b: Second spherical surface (spherical surface) 101: Air conditioner 102: Indoor unit E1: Inner edge E2: Outer edge C1: 1st closed curve C2: Second closed curve R1: 1st area [Prior art documents] [Patent documents]

[0079] [Patent Document 1] JP 2011-89533 A

Claims

1. A bearing structure for a motor that supports a shaft (22c), comprising: A bearing (91a) that rotatably supports the shaft; A first member (83b) for holding the bearing; an elastic member (92) that applies a first force to the bearing to press the bearing toward the first member in a first direction along the rotation axis of the shaft; Equipped with the elastic member has a thermal expansion coefficient greater than that of the bearing; The elastic member has an annular first elastic portion (92a) surrounding the shaft when viewed from the first direction, and a plurality of second elastic portions (92b), The second elastic portions are provided around the rotation axis at intervals along a second direction in which the shaft rotates when viewed from the first direction. Motor bearing structure (91).

2. The plurality of second elastic portions protrude from the first elastic portion toward a radially outer side of the first elastic portion when viewed from the first direction. The motor bearing structure according to claim 1 .

3. When viewed from the first direction, the second elastic portions have an inner edge (E1) extending along the second direction and an outer edge (E2) extending along the second direction and positioned radially outward from the inner edge, a total area S1 of an area occupied by the plurality of second elastic portions when viewed from the first direction; When viewed from the first direction, an area S2 of a first region (R1) between a first closed curve (C1) formed by virtually extending and connecting the inner edges of each of the plurality of second elastic portions along the second direction, and a second closed curve (C2) formed by virtually extending and connecting the outer edges of each of the plurality of second elastic portions along the second direction is The relationship 0.5≦S1 / S2≦0.7 is satisfied.

3. A bearing structure for a motor according to claim 1 or 2.

4. A second member (93) for holding the bearing is further provided, The elastic member is disposed between the first member and the second member in the first direction.

3. A bearing structure for a motor according to claim 1 or 2.

5. The elastic member applies the first force to the bearing via a third member (94).

3. A bearing structure for a motor according to claim 1 or 2.

6. the third member is disposed radially outward of the bearing, the third member is sandwiched between the first member and the elastic member in the first direction and is in contact with the elastic member and the bearing; The motor bearing structure according to claim 5.

7. The bearing is a spherical bearing having a spherical surface (95a, 95b), The elastic member applies the first force to at least a portion of the spherical surface.

3. A bearing structure for a motor according to claim 1 or 2.

8. The bearing has a pair of spherical surfaces, a first spherical surface (95a) and a second spherical surface (95b), located on both sides in the first direction, the first member is in contact with the first spherical surface, The elastic member is in contact with the second spherical surface. The motor bearing structure according to claim 7.

9. The elastic member is disposed such that, when the first direction is parallel to a horizontal direction, some of the second elastic portions are located vertically below the shaft.

3. A bearing structure for a motor according to claim 1 or 2.

10. A stator (83); a rotor (82) rotatably supported relative to the stator; A shaft (22c) fixed to the rotor; Equipped with The shaft is supported by a bearing structure (91) for a motor according to claim 1 or 2. Motor (81).

11. An indoor unit of an air conditioner (101), A heat exchanger (21); a fan (22) for blowing indoor air through the heat exchanger into the room; A motor (81) for driving the fan; Equipped with The motor is a motor according to claim 10. Indoor unit (102).

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