This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2017-178342, filed on Sep. 15, 2017, the entire contents of which are incorporated herein by reference.
Embodiments described herein relate to a mounting structure, rotational machinery, and an air conditioning apparatus.
Rotational machines includes a mounting structure for connecting the shaft of a power source such as a motor and an object such as a fan, to rotate the object. As an example, the object is connected to the outer circumference of the mounting structure with the shaft inserted into a hole of the mounting structure.
Such a mounting structure includes an internal member connected to the shaft and an external member connected to the object, for example. To integrally rotate the two members, an elastic material is molded in-between the two members. Thus, a manufacturing process of two members that are to integrally rotate is complicated.
According to one embodiment, a mounting structure includes a first member, a second member and a support. The first member includes a first outer surface extending along and around a first axis. The second member is provided with a first hole and has a first surface to which the first hole opens, the first hole having the center matching the first axis and extending along the first axis to house the first member. The support is rotatable integrally with the first member around the first axis and has a second surface facing the first surface. One of the first surface and the second surface is provided with a plurality of first dents, the first dents being aligned in a circumferential direction of the first axis. The other of the first surface and the second surface is provided with at least one first bump that fits into at least one of the first dents to limit a relative rotation between the second member and the support around the first axis.
The following describes a first embodiment with reference to
As illustrated in each drawing, an X-axis, a Y-axis, and a Z-axis are defined in the specification. The X-axis, the Y-axis, and the Z-axis are orthogonal to one another. The X-axis is along the width of the air conditioner 10. The Y-axis is along the length (the depth) of the air conditioner 10. The Z-axis is along the height of the air conditioner 10.
As illustrated in
The indoor unit 11 includes a cover 21 and a main body 22. The cover 21 is provided on the ceiling of a room in which the indoor unit 11 is installed, for example. The cover 21 is provided with a plurality of air inlets 25 and a plurality of air outlets 26. The air outlets 26 can be opened or closed by a louver, for example.
The motor 33 is an example of a power source. The turbofan 34 is an example of a fan. The turbofan 34 can also be referred to as a rotational object or a centrifugal fan, for example. The rotational object is not limited to the turbofan 34, and may be another fan such as a propeller fan or another rotational object such as a gear or a pulley, for example. The bushing 36 is an example of a mounting structure. The bushing 36 can also be referred to as a connecting component, a bearing, or a member, for example.
As illustrated in
The housing 31 is provided with an air passage 45 inside. The air passage 45 may be formed by the housing 31 or by a member mounted inside the housing 31, for example. The top wall 41 has an inner surface 41a that faces the inside of the air passage 45. The inner surface 41a faces in the negative Z-axis direction.
The heat exchanger 32 is disposed in the air passage 45. The heat exchanger 32 is mounted on the inner surface 41a of the top wall 41 and has a tubular shape extending in the negative Z-axis direction, for example. The heat exchanger 32 includes piping through which refrigerant flows, and fins, for example. The heat exchanger 32 exchanges heat between air passing through the heat exchanger 32 and the refrigerant to warm or cool the air. The heat exchanger 32 is not limited to this example.
The motor 33 is a direct current (DC) motor the rotation speed of which can be changed by inverter control, for example. The motor 33 is attached to the inner surface 41a of the top wall 41, for example, with bolts extending from the inner surface 41a and nuts.
The motor 33 has a shaft 33a. The shaft 33a can also be referred to as a drive shaft or a rotation shaft, for example. The shaft 33a extends in the negative Z-axis direction. The motor 33 is driven to rotate the shaft 33a around the central axis of the shaft 33a.
The turbofan 34 is surrounded by the heat exchanger 32 in the air passage 45. The turbofan 34 is made of a synthetic resin, for example. The turbofan 34 may be made of another material. The turbofan 34 includes a hub 51, a support 52, a connection 53, a plurality of blades 54, and a shroud 55.
The hub 51 has a tubular shape extending in the Z-axis direction. The hub 51 is mounted on the shaft 33a of the motor 33 through the bushing 36. The support 52 has an annular shape lying in the X-Y plane. The support 52 is disposed closer to the top wall 41 than the hub 51 and surrounds the motor 33.
The connection 53 has a tubular, substantially circular truncated cone shape, for example. The connection 53 connects the end of the hub 51 and the inner circumference of the support 52. The multiple blades 54 are arranged in annular form and extend in the negative Z-axis direction from the support 52. The shroud 55 has an annular shape lying in the X-Y plane and is connected to the edges of the blades 54.
The motor 33 rotates the shaft 33a to rotate the turbofan 34. As illustrated with the arrows in
The cap 35 fixes the turbofan 34 and the bushing 36 to the shaft 33a of the motor 33. For example, the cap 35 is attached to the shaft 33a with screw clamps and supports the turbofan 34 and the bushing 36.
The first member 61, the second member 62, and the third member 63 are made of a relatively lightweight metal such as an aluminum alloy, for example. The first member 61, the second member 62, and the third member 63 are made of the same material. Young's moduli of the first member 61, the second member 62, and the third member 63 are thus substantially equal to one another. As with the first member 61, the second member 62, and the third member 63, the washer 64 is made of a metal, for example.
The first member 61, the second member 62, the third member 63, and the washer 64 may be made of another material such as a synthetic resin. The first member 61, the second member 62, and the third member 63 may be made of materials different from one another.
The first member 61 has a tube 71 and a flange 72. The tube 71 can also be referred to as an extension, for example. The flange 72 is an example of a support. The flange 72 and the first member 61 including the tube 71 may be separate members.
The tube 71 has a substantially cylindrical shape extending in a Z-axis direction. The tube 71 is provided with a first through hole 75 that extends in the Z-axis direction. The first through hole 75 is an example of a third hole.
The rotation center Cr is the central axis of the shaft 33a of the motor 33 and a virtual central axis of the first through hole 75 extending along the Z-axis. The central axis of the shaft 33a and the central axis of the first through hole 75 may differ from each other. The first through hole 75 has a substantially circular shape having a center matching the rotation center Cr and extends along the rotation center Cr. In other words, the first through hole 75 extends along and around the rotation center Cr.
The first inner circumferential surface 71a sections (defines) the first through hole 75 and has a substantially cylindrical shape extending along and around the rotation center Cr. In other words, the first inner circumferential surface 71a forms the first through hole 75. A part of the first inner circumferential surface 71a may form the first through hole 75. The first inner circumferential surface 71a faces the inside of the first through hole 75. That is, the first through hole 75 is inside the first inner circumferential surface 71a.
The first outer circumferential surface 71b is opposite the first inner circumferential surface 71a. As illustrated in
The first central axis C1 is a virtual central axis of the first outer circumferential surface 71b extending along the Z-axis. The first central axis C1 is parallel to the rotation center Cr and located differently from the rotation center Cr. In other words, the first central axis C1 differs from the rotation center Cr. The first inner circumferential surface 71a and the first through hole 75 are eccentric from the first outer circumferential surface 71b. The first central axis C1 may be tilted with respect to the rotation center Cr.
The first outer circumferential surface 71b has a substantially cylindrical shape extending along the first central axis C1. Thus, the first outer circumferential surface 71b is in rotational symmetry with respect to the first central axis C1. The first central axis C1 is thus also a symmetrical axis of the first outer circumferential surface 71b.
As illustrated in
The tube 71 is provided with a projection 76. The projection 76 projects inward from the first inner circumferential surface 71a of the first through hole 75. The length of the projection 76 is shorter than that of the first through hole 75 in the Z-axis direction. In other words, the projection 76 is located on a part of the first inner circumferential surface 71a in the Z-axis direction. The projection 76 is not limited to this example.
Part of the first inner circumferential surface 71a may be provided with a fitting such as a depression or the projection 76 as described in the first embodiment. In this case, the rotation center Cr matches the center of a circular cross section part with no depression or projection, of the first through hole 75. Alternatively, the first through hole 75 may be provided with a depression or a projection on the entire first inner circumferential surface 71a in the Z-axis direction. In this case, the rotation center Cr matches the center of an arc-shaped part of the cross section of the first through hole 75. When the cross section of the first through hole 75 includes two or more arc-shaped parts, the rotation center Cr matches the center of one having the center closest to the geometric center of gravity (centroid) of the cross section of the first through hole 75.
The first through hole 75 with the circular cross section or the cross section including the arc-shaped part has been described above. The cross section of the first through hole 75 may include no arc-shaped part. In this case, the rotation center Cr coincides with the symmetrical axis of a rotationally symmetric part of a cross section with no depression or projection, of the first through hole 75. The depression or projection may be provided on the entire first inner circumferential surface 71a in the Z-axis direction. In this case, the rotation center Cr matches the symmetrical axis of the largest rotational symmetric part of a cross section of the first through hole 75. When the shape of the first through hole 75 is not any of the above shapes, the rotation center Cr matches the geometric center of the cross section of the first through hole 75.
The shaft 33a of the motor 33 is inserted into the first through hole 75. The shaft 33a is what is called a D-cut shaft with a cutout 33b. The shaft 33a is inserted into the first through hole 75, with the projection 76 fitted into the cutout 33b. This limits relative rotation between the shaft 33a and the first member 61, and transmits the rotation of the shaft 33a to the first member 61.
The flange 72 is made integrally with the tube 71. The flange 72 thus can rotate integrally with the tube 71 around the first central axis C1. The flange 72 projects from the first outer circumferential surface 71b of the tube 71. The flange 72 is substantially circular plate-like lying in the X-Y plane. The flange 72 may have another shape.
The flange 72 projects from the end of the first outer circumferential surface 71b in the positive Z-axis direction. The flange 72 has a first receiving surface 72a. The first receiving surface 72a is an example of a second surface. The first receiving surface 72a is substantially flat, facing in the negative Z-axis direction. The first receiving surface 72a may be a conical surface, for example.
The second member 62 has a substantially cylindrical shape extending in the Z-axis direction. The second member 62 is provided with a first hole 81 that extends through the second member 62 in the Z-axis direction.
As illustrated in
As illustrated in
The second inner circumferential surface 62a sections (defines) the first hole 81 and has a substantially cylindrical shape extending alone and around the first central axis C1. In other words, the second inner circumferential surface 62a forms the first hole 81. A part of the second inner circumferential surface 62a may form the first hole 81. The second inner circumferential surface 62a faces the inside of the first hole 81. That is, the first hole 81 is inside the second inner circumferential surface 62a.
The second inner circumferential surface 62a has a substantially cylindrical shape extending along the first central axis C1. Thus, the second inner circumferential surface 62a is in rotational symmetry with respect to the first central axis C1. The first central axis C1 is thus also a symmetrical axis of the second inner circumferential surface 62a.
As described above, the centers (the first central axis C1) of the first hole 81 and the second inner circumferential surface 62a substantially coincide with the center (the first central axis C1) of the first outer circumferential surface 71b of the tube 71 of the first member 61. The second member 62 can rotate around the first central axis C1 with respect to the first member 61 unless another member limits the relative rotation between the first member 61 and the second member 62.
The tube 71 of the first member 61 is housed in the first hole 81. A radius of the first hole 81 is substantially equal to a radius of the first outer circumferential surface 71b of the tube 71 of the first member 61. The second inner circumferential surface 62a thus contacts with the first outer circumferential surface 71b, thereby limiting the movement of the second member 62 with respect to the first member 61 in a direction intersecting the Z-axis. A part of the second inner circumferential surface 62a may be slightly apart from the first outer circumferential surface 71b.
The second outer circumferential surface 62b is opposite the second inner circumferential surface 62a. As illustrated in
The second central axis C2 is a virtual central axis of the second outer circumferential surface 62b extending along the Z-axis. The second central axis C2 is parallel to the rotation center Cr and the first central axis C1. The second central axis C2 is in a different location from that of the first central axis C1. In other words, the second central axis C2 differs from the first central axis C1. The second inner circumferential surface 62a and the first hole 81 are eccentric from the second outer circumferential surface 62b. The second central axis C2 may be tilted with respect to the rotation center Cr or with respect to the first central axis C1.
A distance r1 between the rotation center Cr and the first central axis C1 is substantially equal to a distance r2 between the first central axis C1 and the second central axis C2. Because of this, as illustrated in
The second outer circumferential surface 62b has a substantially cylindrical shape extending alone the second central axis C2. Thus, the second outer circumferential surface 62b is in rotational symmetry with respect to the second central axis C2. The second central axis C2 is also a symmetrical axis of the second outer circumferential surface 62b.
As illustrated in
The tube 71 is housed in the first hole 81. The second end face 62c facing in the positive Z-axis direction opposes the first receiving surface 72a of the flange 72. The flange 72 supports the second member 62 and limits the movement of the second member 62 with respect to the first member 61 in the positive Z-axis direction.
The third member 63 has a substantially cylindrical shape extending in the Z-axis direction. The third member 63 is provided with a second hole 85 that extends through the third member 63 in the Z-axis direction.
As illustrated in
As illustrated in
The third inner circumferential surface 63a sections (defines) the second hole 85 and has a substantially cylindrical shape extending along and around the second central axis C2. In other words, the third inner circumferential surface 63a forms the second hole 85. A part of the third inner circumferential surface 63a may form the second hole 85. The third inner circumferential surface 63a faces the inside of the second hole 85. That is, the second hole 85 is inside the third inner circumferential surface 63a. The second inner circumferential surface 62a and the first hole 81 are eccentric from the third inner circumferential surface 63a.
The substantially cylindrical, third inner circumferential surface 63a extending along and about the second central axis C2 is thus in rotational symmetry with respect to the second central axis C2. The second central axis C2 is also a symmetrical axis of the third inner circumferential surface 63a.
As described above, the center (the second central axis C2) of the second hole 85 and the third inner circumferential surface 63a and the center (the second central axis C2) of the second outer circumferential surface 62b of the second member 62 substantially coincide with each other. The third member 63 can rotate around the second central axis C2 with respect to the second member 62 unless another member limits the relative rotation between the second member 62 and the third member 63.
The second member 62 is housed in the second hole 85. A radius of the second hole 85 and a radius of the second outer circumferential surface 62b of the second member 62 are substantially equal to each other. The third inner circumferential surface 63a thus contacts with the second outer circumferential surface 62b, thereby limiting the movement of the third member 63 with respect to the second member 62 in a direction intersecting the Z-axis. A part of the third inner circumferential surface 63a may be slightly apart from the second outer circumferential surface 62b.
The third outer circumferential surface 63b is opposite the third inner circumferential surface 63a. As illustrated in
As illustrated in
Alternatively, for example, the third member 63 and the turbofan 34 may be formed from the same material into a single component.
As illustrated in
The tube 71 is housed in the first hole 81 and the second member 62 is housed in the second hole 85. As a result, the third end face 63c facing in the positive Z-axis direction opposes the first receiving surface 72a of the flange 72. The flange 72 supports the third member 63, thereby limiting the movement of the third member 63 with respect to the first member 61 in the positive Z-axis direction.
The washer 64 is placed between the cap 35 and the first to third members 61 to 63. The washer 64 has a substantially disk shape. The washer 64 is provided with a second through hole 88 that extends through the washer 64 in the Z-axis direction. The second through hole 88 has a substantially circular cross section. A radius of the second through hole 88 is larger than that of the first through hole 75.
The shaft 33a of the motor 33 is inserted into the first through hole 75 and then into the second through hole 88. A male screw 33c provided at the distal end of the shaft 33a is inserted into the second through hole 88, for example. A radius of the male screw 33c is smaller than that of the second through hole 88.
The washer 64 has a second receiving surface 64a. The second receiving surface 64a is an example of a sixth surface. The second receiving surface 64a faces in the positive Z-axis direction. The second through hole 88 opens to the second receiving surface 64a.
The second receiving surface 64a faces the first end face 71d of the first member 61, the second end face 62d of the second member 62, and the third end face 63d of the third member 63. The second end face 62d and the third end face 63d form substantially the same plane. The first end face 71d is apart from the second end face 62d and the third end face 63d in the positive Z-axis direction.
The cap 35 is provided with a female screw 35a. The male screw 33c of the shaft 33a is screwed into the female screw 35a. The cap 35 thereby supports the second end face 62d of the second member 62 and the third end face 63d of the third member 63 via the washer 64. The cap 35 and the washer 64 thus limit the movement of the first member 61, the second member 62, and the third member 63 with respect to the shaft 33a of the motor 33 in the negative Z-axis direction. The cap 35 limits the movement of the washer 64 with respect to the first member 61, the second member 62, and the third member 63 in the negative Z-axis direction.
The cap 35 supports the flange 72 of the first member 61 through the washer 64, the second member 62, and the third member 63. The second member 62 and the third member 63 are thus held between the cap 35 and the flange 72.
The first receiving surface 72a of the flange 72 and the second end face 62c of the second member 62 are each provided with a plurality of first bumps 91 and a plurality of first dents 92. The first bumps 91 may be formed on one of the first receiving surface 72a and the second end face 62c while the first dents 92 may be formed on the other of the first receiving surface 72a and the second end face 62c.
As illustrated in
The first bumps 91 are arranged around the first central axis C1 at intervals of one degree, for example. The pitch of the first bumps 91 on the first receiving surface 72a and that of the first bumps 91 on the second end face 62c may differ from each other.
The first dents 92 are formed between the respective adjacent first bumps 91 aligned around the first central axis C1. The first dents 92 are thus aligned around the first central axis C1 at a substantially constant angle (pitch). The first bumps 91 and the first dents 92 are alternately arranged around the first central axis C1.
The first dents 92 are arranged around the first central axis C1 at intervals of one degree, for example. The first dents 92 on the first receiving surface 72a and the first dents 92 on the second end face 62c may be arranged at differ pitches.
The first bumps 91 and the first dents 92 each have a substantially triangular cross section. Alternatively, the shape of the cross section may be, for example, rectangular or semicircular.
As illustrated in
As illustrated in
The first bumps 91 and the first dents 92 are formed by press working, for example. Alternatively, for example, the first bumps 91 and the first dents 92 may be formed by another method such as cutting.
As illustrated in
As illustrated in
The second bumps 95 and the second dents 96 on the second end face 62d are an example of a first fitting. The second bumps 95 and the second dents 96 on the third end face 63d are an example of a second fitting. The second bumps 95 and the second dents 96 on the second receiving surface 64a are an example of a third fitting.
As illustrated in
The second bumps 95 are arranged around the second central axis C2 at intervals of one degree, for example. The second bumps 95 on the second end face 62d, the second bumps 95 on the third end face 63d, and the second bumps 95 on the second receiving surface 64a may be arranged at different pitches from one another.
The second dents 96 are formed between the respective adjacent second bumps 95 arranged around the second central axis C2. The second dents 96 are thus arranged around the second central axis C2 at intervals (pitch) of a substantially constant angle. The second bumps 95 and the second dents 96 are alternately arranged around the second central axis C2.
The second dents 96 are arranged around the second central axis C2 at intervals of one degree, for example. The second dents 96 on the second end face 62d, the second dents 96 on the third end face 63d, and the second dents 96 on the second receiving surface 64a may be arranged at different pitches from one another.
The second bumps 95 and the second dents 96 each have a substantially triangular cross section. Alternatively, the shape of the cross section may be, for example, rectangular or semicircular, for example.
As illustrated in
As illustrated in
The second bumps 95 on the second end face 62d and the third end face 63d fit into the second dents 96 on the second receiving surface 64a. Likewise, the second bumps 95 on the second receiving surface 64a fit into the second dents 96 on the second end face 62d and the third end face 63d. The alignment position of the second dents 96 on the second end face 62d and the second dents 96 on the third end face 63d can be changed by relatively rotating the second member 62 and the third member 63 around the second central axis C2. This makes it possible to adjust a relative rotation angle between the second member 62 and the third member 63 around the second central axis C2 and restrict the second member 62 and the third member 63 from relatively rotating around the second central axis C2 by fitting the second bumps 95 on the second receiving surface 64a of the washer 64 into the second dents 96 on the second end face 62d and the third end face 63d. In
The second bumps 95 and the second dents 96 are formed by press working, for example. Alternatively, for example, the second bumps 95 and the second dents 96 may be formed by another method such as cutting.
As illustrated in
As described above, the first member 61, the second member 62, and the third member 63 are assembled in accordance with the position of the center of gravity of the turbofan 34 integrated with the third member 63.
Specifically, the first member 61, the second member 62, and the third member 63 are disposed to rotate around their respective centers (the first central axis C1 or the second central axis C2), so that the central axis (the rotation center Cr) of the shaft 33a of the motor 33 and the gravity center of the turbofan 34 coincide with each other.
To measure the position of the gravity center of the turbofan 34, the turbofan 34 is placed on three triangularly-arranged pressure sensors. Alternatively, the position of the gravity center of the turbofan 34 may be measured by rotating the turbofan 34, for example.
With the rotation center Cr matching the gravity center of the turbofan 34, the first bumps 91 on the first receiving surface 72a of the first member 61 fit into the first dents 92 on the second end face 62c of the second member 62, and the first bumps 91 on the second end face 62c of the second member 62 fit into the first dents 92 on the first receiving surface 72a of the first member 61. The second bumps 95 on the second end face 62d of the second member 62 and the third end face 63d of the third member 63 fit into the second dents 96 on the second receiving surface 64a of the washer 64, and the second bumps 95 on the second receiving surface 64a of the washer 64 fit into the second dents 96 on the second end face 62d of the second member 62 and the third end face 63d of the third member 63.
The cap 35 is attached to the shaft 33a of the motor 33, holding the second member 62 and the third member 63 between the cap 35 and the flange 72 of the first member 61. Thereby, the cap 35 pushes the first receiving surface 72a of the first member 61 provided with the first bumps 91 and the first dents 92 onto the second end face 62c of the second member 62 provided with the first bumps 91 and the first dents 92. In addition, the cap 35 pushes the second receiving surface 64a of the washer 64 provided with the second bumps 95 and the second dents 96 onto the second end face 62d of the second member 62 and the third end face 63d of the third member 63 provided with the second bumps 95 and the second dents 96.
The first member 61, the second member 62, the third member 63, and the washer 64 are restricted from relatively rotating by the fitting of the first bumps 91 into the first dents 92 and the fitting of the second bumps 95 into the second dents 96. This makes it possible for the shaft 33a of the motor 33 to transmit the rotation (torque) to the turbofan 34 via the first member 61, the second member 62, the third member 63, and the washer 64.
The gravity center of the turbofan 34 may be set to any position on the rotation center Cr along the Z-axis. The gravity center of the turbofan 34 can coincide with the rotation center Cr in a plan view from the extending direction of the rotation center Cr (the positive or negative Z-axis direction).
Due to the position of the rotation center Cr coinciding with the gravity center of the turbofan 34, the turbofan 34 is prevented from vibration during rotation. When the position of the rotation center Cr deviates from the gravity center of the turbofan 34, the vibration occurring from the rotating turbofan 34 can be reduced by setting the position of the rotation center Cr closer to the gravity center of the turbofan 34.
For example, when the gravity center of the turbofan 34 and the second central axis C2 being the center of the turbofan 34 and the third member 63 coincide with each other, the first member 61, the second member 62, and the third member 63 are arranged as illustrated in
When the first member 61, the second member 62, and the third member 63 are arranged as illustrated in
Misalignment of the third member 63 by insert molding may, for example, lead to the deviation of the gravity center of the turbofan 34 from the position of the second central axis C2. In this case, the first member 61, the second member 62, and the third member 63 are rotated around their respective centers (the first central axis C1 or the second central axis C2) from their positions illustrated in
The position of the gravity center CG is represented by polar coordinates (Rf,θf) with the second central axis C2 as the origin. The gravity center CG is located in a distance Rf from the second central axis C2 and at an angle rotated by angle θf around the second central axis C2 from the position illustrated in
As illustrated in
The rotation angle θ1 of the first member 61 for positioning the rotation center Cr at the polar coordinates (Rf,θf) is found by the following Expression 1:
The rotation angle θ2 of the second member 62 for positioning the rotation center Cr at the polar coordinates (Rf,θf) is found by the following Expression 2:
As described above, the first member 61 and the second member 62 are rotated to make the central axis (the rotation center Cr) of the shaft 33a of the motor 33 and the gravity center CG of the turbofan 34 substantially coincide with each other. In this case, the turbofan 34 and the shaft 33a of the motor 33 appear to be eccentric with each other, however, the vibration from the rotating turbofan 34 is prevented.
In the positions illustrated in
Rf=r1+r2=2×r1=2×r2
When the distance Rf is equal to or smaller than the sum of the distance r1 and distance r2 as a result of the Expression 3, the bushing 36 can place the rotation center Cr and the gravity center CG at the same position.
As described above, the second member 62 is rotated around the first central axis C1 with respect to the first member 61 and fixed to the first member 61 in accordance with the position of the gravity center CG of the turbofan 34. In other words, the second member 62 can be attached to the first member 61 at different angles around the first central axis C1 relative to the first member 61.
In addition, the third member 63 is rotated around the second central axis C2 with respect to the second member 62 and fixed to the second member 62 in accordance with the position of the gravity center CG of the turbofan 34. In other words, the third member 63 can be attached to the second member 62 at different angles around the second central axis C2 relative to the second member 62. This can make the central axis (the rotation center Cr) of the shaft 33a of the motor 33 and the position of the gravity center CG of the turbofan 34 coincide with each other.
In the bushing 36 of the air conditioner 10 according to the first embodiment described above, the first receiving surface 72a of the flange 72 is integrally rotatable with the first member 61 around the first central axis C1, facing the second end face 62c of the second member 62. The second end face 62c and the first receiving surface 72a are provided with the first dents 92 and the first bumps 91 which fit into the first dents 92 to limit the relative rotation between the second member 62 and the flange 72. Thereby, the bushing 36 that limits the relative rotation between the first member 61 and the second member 62 can be easily manufactured without the necessity for attachment of a member such as pins for fixing the first member 61 and the second member 62 to each other.
The first bumps 91 project in the direction along the first central axis C1 and the first dents 92 are depressed in the direction along the first central axis C1. Thereby, the first bumps 91 and the first dents 92 can be more easily formed by press working such as coining than when the bumps and dents are formed on the first outer circumferential surface 71b of the first member 61 and the second inner circumferential surface 62a of the second member 62, for example. In addition, the bumps and dents (the first bumps 91 and the first dents 92) can be arranged more outside than the first outer circumferential surface 71b and the second inner circumferential surface 62a in the radial direction of the first central axis C1. The more radially outside the bumps and dents are located, in general, the longer the circumferential distance per angle is. Because of this, in arranging the first dents 92 having the same size, for example, the pitch of the first dents 92 around the first central axis C1 can be decreased. This makes it possible to more accurately attach the second member 62 to the first member 61 at a desired angle around the first central axis C1.
The relative rotation between the first member 61 and the second member 62 can be limited not by any of adhesive bonding, welding, and press fitting but by the fitting of the first bumps 91 into the first dents 92. Thereby, the bushing 36 can be easily disassembled for maintenance of the air conditioner 10, for example.
The first dents 92 extend radially with respect to the first central axis C1. The first bumps 91 extend in the radial direction of the first central axis C1. By the fitting of such a first bump 91 into at least one of the first dents 92, the relative rotation angle between the first member 61 and the second member 62 can be adjusted and the first member 61 and the second member 62 can be restricted from relatively rotating.
The rotation center Cr of the first inner circumferential surface 71a of the first member 61 is eccentric from the first central axis C1 of the first outer circumferential surface 71b. The first central axis C1 of the second inner circumferential surface 62a of the second member 62 is eccentric from the second central axis C2 of the second outer circumferential surface 62b. The first member 61 is housed in the first hole 81 of the second member 62 while the second member 62 is housed in the second hole 85 of the third member 63. For example, the second member 62 is attached to the first member 61 at a desired angle around the first central axis C1 and the third member 63 is attached to the second member 62 at a desired angle around the second central axis C2, to make the second central axis C2 coincide with the rotation center Cr or place the second central axis C2 at a desired position different from the rotation center Cr. Thereby, the rotation center Cr can coincide with the gravity center CG of the bushing 36, for example, preventing the vibration of the turbofan 34 to which the bushing 36 is attached and reducing the occurrence of noise due to the vibration. This also eliminates the necessity for adjusting the gravity center of the bushing 36 using a weight and for adding a reinforcing structure for vibration reduction, which results in reducing the manufacturing cost of the air conditioner 10 including the bushing 36.
The second receiving surface 64a of the washer 64 faces the second end face 62d, which is opposite the second end face 62c, of the second member 62 and the third end face 63d of the third member 63. The second bumps 95 and the second dents 96 are provided on the second end face 62d, the third end face 63d, and the second receiving surface 64a. The second bumps 95 on the second receiving surface 64a fit into the second dents 96 on the second end face 62d and the third end face 63d and the second bumps 95 on the second end face 62d and the third end face 63d fit into the second dents 96 on the second receiving surface 64a, thereby limiting the relative rotation among the second member 62, the third member 63, and the washer 64. This makes it possible to easily manufacture the bushing 36 that limits the relative rotation between the second member 62 and the third member 63 without the necessity for attachment of a member such as pins for fixing the second member 62 and the third member 63 to each other, for example.
The second dents 96 extend radially with respect to the second central axis C2. The second bumps 95 extend in the radial direction of the second central axis C2. The second bumps 95 on the second receiving surface 64a fit into the second dents 96 on the second end face 62d and the third end face 63d while the second bumps 95 on the second end face 62d and the third end face 63d fit into the second dents 96 on the second receiving surface 64a, which makes it possible to adjust the relative rotation angle among the second member 62, the third member 63, and the washer 64 and limit the relative rotation among them.
The rotation center Cr, the first central axis C1, and the second central axis C2 are in parallel with one another. Thereby, the rotation center Cr can be easily set to a desired position on a plane orthogonal to the rotation center Cr, the first central axis C1, and the second central axis C2.
The distance r2 between the first central axis C1 and the second central axis C2 is equal to the distance r1 between the first central axis C1 and the rotation center Cr. Thus, the rotation center Cr can be set to the second central axis C2.
The first outer circumferential surface 71b and the second inner circumferential surface 62a are in rotational symmetry with respect to the first central axis C1. The second outer circumferential surface 62b and the third inner circumferential surface 63a are in rotational symmetry with respect to the second central axis C2. This structure makes it possible to easily attach the second member 62 to the first member 61 at different angles around the first central axis C1. This structure also makes it possible to easily attach the third member 63 to the second member 62 at different angles around the second central axis C2. The rotation center Cr can thus be made coincident with the second central axis C2 or be set to a desired position different from the second central axis C2.
The numbers of the first bumps 91 and the first dents 92 formed on the first receiving surface 72a are equal to the numbers of the first bumps 91 and the first dents 92 formed on the second end face 62c. Thereby, the first bumps 91 and first dents 92 can be easily formed on the first receiving surface 72a and on the second end face 62c by press working using the same mold.
The same numbers of the second bumps 95 and the second dents 96 are formed on the second receiving surface 64a, on the second end face 62d, and on the third end face 63d. The second bumps 95 and the second dents 96 can thus be easily formed on the second receiving surface 64a, on the second end face 62d, and on the third end face 63d by press working using the same mold.
The following describes a second embodiment with reference to
The number of the second dents 96 on the third end face 63d is larger than the number of the second dents 96 on the second end face 62d and the number of the second bumps 95 on the second receiving surface 64a. The second dents 96 and the second bumps 95 are aligned on the second end face 62d and on the second receiving surface 64a, respectively, around the second central axis C2 at intervals of 90 degrees, for example.
The second dents 96 are arranged with spacing on the second end face 62d in the circumferential direction of the second central axis C2. Between the two adjacent second dents 96, the second end face 62d is substantially flat. The second bumps 95 and the second dents 96 are alternately arranged on the third end face 63d around the second central axis C2. The second bumps 95 are arranged with spacing on the second receiving surface 64a in the circumferential direction of the second central axis C2. Between the two adjacent second bumps 95, the second receiving surface 64a is substantially flat.
The second bumps 95 on the second receiving surface 64a fit into the second dents 96 on the second end face 62d and the third end face 63d. The position where the second dents 96 on the second end face 62d and the second dents 96 on the third end face 63d align with each other can be changed by relatively rotating the second member 62 and the third member 63 around the second central axis C2. This makes it possible to adjust a relative rotation angle between the second member 62 and the third member 63 around the second central axis C2, and restrict the second member 62 and the third member 63 from relatively rotating around the second central axis C2 by the fitting of the second bumps 95 on the second receiving surface 64a of the washer 64 into the second dents 96 on the second end face 62d and the third end face 63d.
The number of the first dents 92 on the first receiving surface 72a is larger than the number of the first bumps 91 on the second end face 62c. The first bumps 91 are arranged on the second end face 62c around the first central axis C1 at intervals of 90 degrees, for example.
The first bumps 91 are arranged on the second end face 62c with spacing in the circumferential direction of the first central axis C1. Between the two adjacent first bumps 91, the second end face 62c is substantially flat. The first bumps 91 and the first dents 92 are alternately arranged on the first receiving surface 72a around the first central axis C1.
The first bumps 91 on the second end face 62c fit into the first dents 92 on the first receiving surface 72a. The fitting position of the first bumps 91 on the second end face 62c and the first dents 92 on the first receiving surface 72a can be changed by relatively rotating the first member 61 and the second member 62 around the first central axis C1. This makes it possible to adjust the relative rotation angle between the second member 62 and the first member 61 including the flange 72 around the first central axis C1, and to limit the relative rotation between the second member 62 and the first member 61.
In the bushing 36 of the air conditioner 10 in the second embodiment, the number of the first dents 92 on the first receiving surface 72a is larger than the number of first bumps 91 on the second end face 62c. As a result, the first bumps 91 can be easily formed by cutting, for example.
The number of the second dents 96 on the third end face 63d is larger than the number of the second bumps 95 on the second receiving surface 64a. Thereby, the second bumps 95 can be easily formed by cutting, for example.
The following describes a third embodiment with reference to
The number of the second dents 96 on the second end face 62d is larger than the number of the second bumps 95 on the third end face 63d. In addition, the number of the second dents 96 on the second receiving surface 64a is larger than the number of the second bumps 95 on the third end face 63d. The second bumps 95 are arranged on the third end face 63d around the second central axis C2 at intervals of 90 degrees, for example.
The second bumps 95 and the second dents 96 are alternately arranged on both of the second end face 62d and the second receiving surface 64a around the second central axis C2. The second bumps 95 are arranged with spacing on the third end face 63d in the circumferential direction of the second central axis C2. The third end face 63d is substantially flat between the two adjacent second bumps 95.
The second bumps 95 on the second end face 62d and the third end face 63d fit into the second dents 96 on the second receiving surface 64a. The position where the second bumps 95 on the second end face 62d and the second bumps 95 on the third end face 63d align with each other can be changed by relatively rotating the second member 62 and the third member 63 around the second central axis C2. Thereby, the relative rotation angle around the second central axis C2 between second member 62 and the third member 63 can be adjusted. By fitting such second bumps 95 on the second end face 62d and third end face 63d into the second dents 96 on the second receiving surface 64a of the washer 64, the second member 62 and the third member 63 can be restricted from relatively rotating around the second central axis C2.
The number of the first dents 92 on the second end face 62c is larger than the number of the first bumps 91 on the first receiving surface 72a. The first bumps 91 are arranged on the first receiving surface 72a around the first central axis C1 at intervals of 90 degrees, for example.
The first bumps 91 and the first dents 92 are alternately arranged on the second end face 62c around the first central axis C1. The first bumps 91 are arranged with spacing on the first receiving surface 72a in the circumferential direction of the first central axis C1. The first receiving surface 72a is substantially flat between the two adjacent first bumps 91.
The first bumps 91 on the first receiving surface 72a fit into the first dents 92 on the second end face 62c. The fitting position of the first bumps 91 on the first receiving surface 72a and the first dents 92 on the second end face 62c can be changed by relatively rotating the first member 61 and the second member 62 around the first central axis C1. This makes it possible to adjust the relative rotation angle between the second member 62 and the first member 61 including the flange 72 around the first central axis C1, and to limit the relative rotation between the second member 62 and the first member 61.
In the bushing 36 of the air conditioner 10 in the third embodiment, the number of the first dents 92 on the second end face 62c is larger than the number of the first bumps 91 on the first receiving surface 72a. As a result, the first bumps 91 can be easily formed by cutting, for example.
The number of the second dents 96 on the second receiving surface 64a is larger than the number of the second bumps 95 on the third end face 63d. The second bumps 95 can thus be easily formed by cutting, for example.
In the second and the third embodiments, the bushing 36 is provided with the first bumps 91 and the second bumps 95. Thereby, torque is distributed to the first bumps 91 and the second bumps 95. The bushing 36 may be provided with a single first bump 91 and a single second bump 95. With the single first bump 91 alone, the relative rotation angle between the second member 62 and the first member 61 including the flange 72 is adjustable around the first central axis C1. With the single second bump 95 alone, the relative rotation angle between the second member 62 and the third member 63 is adjustable around the second central axis C2.
According to at least one of the first to third embodiments, the second surface of the support, which can rotate integrally with the first member around the first axis, faces the first surface of the second member. On the first surface and the second surface, the multiple first dents and the first bump are provided, and the first bump fits into the first dents to limit the relative rotation between the second member and the support. This makes it possible to easily manufacture the mounting structure that limits the relative rotation between the first member and the second member without the necessity for attachment of a member such as pins for fixing the first member and the second member to each other.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
Number | Date | Country | Kind |
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2017-178342 | Sep 2017 | JP | national |