Motor device

Abstract

A motor device includes a motor body, a housing accommodating the motor body, a printed circuit board controlling driving of the motor body and supported by the housing, and a ground bus bar arranged between the motor body and the printed circuit board and connecting grounds of the motor body and the printed circuit board, wherein the ground bus bar is a flexible metal plate-like rod, the ground bus bar includes a first connecting portion fixed to the motor body, a second connecting portion fixed to the printed circuit board, and an extension portion extending from the first connecting portion to the second connecting portion, the printed circuit board includes a through hole for ground connection, the first connecting portion is screwed to the motor body, and the second connecting portion is inserted into the through hole and elastically deformed to engage with the through hole.

Description

Technical Field

[0001] The present invention relates to a motor device. Background Art

[0002] A method of electrically connecting a motor body and a ground of a printed circuit board has been proposed (see, for example, Patent Document 1).

[0003] [Prior Art Document]

[0004] [Patent Document]

[0005] [Patent Document 1] Japanese Unexamined Patent Application Publication No. 2014-017929 Summary of the Invention

[0006] [Problems to be solved by the present invention]

[0007] For example, it is conceivable to electrically connect the motor body and the ground of the printed circuit board using a ground bus bar. In this case, if the ground bus bar and the printed circuit board are connected by using, for example, screws, the assembly workability may be reduced.

[0008] Therefore, an object of the present invention is to provide a motor device having improved assembly workability.

[0009] [Methods of solving the problem]

[0010] The above-mentioned purpose is achieved by a motor device, which includes: a motor body; a shell, which accommodates the motor body; a printed circuit board, which controls the drive of the motor body and is supported by the shell; and a grounding bus bar, which is arranged between the motor body and the printed circuit board and connects the grounding of the motor body and the printed circuit board, wherein the grounding bus bar is an elastic metal plate-shaped rod, and the grounding bus bar includes: a first connecting part, which is fixed to the motor body; a second connecting part, which is fixed to the printed circuit board; and an extension part, which extends from the first connecting part to the second connecting part, and the printed circuit board includes a through hole for grounding connection, the first connecting part is screwed to the motor body, and the second connecting part is inserted into the through hole and elastically deformed to engage with the through hole.

[0011] [Effects of the Invention]

[0012] According to the present invention, a motor device having improved assembly workability can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a cross-sectional view of the air blowing device according to this embodiment;

[0014] Figure 2 is a perspective view of the periphery of a printed circuit board with the housing removed;

[0015] Figure 3 is a perspective view of the periphery of a ground bus bar of a printed circuit board with the periphery thereof removed;

[0016] Figure 4A and Figure 4B is an illustrative view of a ground bus bar;

[0017] Figure 5A and Figure 5B is an illustrative view of a ground bus bar;

[0018] Figure 6 is an explanatory view of the assembly work of the ground bus bar and the printed circuit board;

[0019] Figure 7 is an explanatory view of the assembly work of the ground bus bar and the printed circuit board;

[0020] Figure 8 is an explanatory view of the assembly work of the ground bus bar and the printed circuit board;

[0021] Figure 9 is an enlarged view of the through hole into which the second connecting portion is inserted; and

[0022] Figure 10 is an enlarged view of the second connecting portion. DETAILED DESCRIPTION

[0023] Figure 1 is a cross-sectional view of the air blowing device A according to the present embodiment. Figure 1 The cross section including the central axis of the rotating shaft 42 is shown, which will be described later. The air blowing device A includes housings 10 and 20, a motor M, a fan I rotated by the motor M, and a printed circuit board PB electrically connected to the motor M. Figure 1 1 and 2. A fan 1 is briefly shown in FIG. The motor M and the fan 1 are located on one side of a housing 10, and a housing 20 is attached to the other side of the housing 10. The housings 10 and 20 are each formed in a half-shell shape and are assembled with each other to accommodate a printed circuit board PB in the housings 10 and 20. The housings 10 and 20 are made of synthetic resin, but are not limited thereto and may be made of metal.

[0024] The motor M will now be described. The motor M is located between the fan 1 and the housing 10. The motor M includes a coil 30, a rotor 40, a stator 50, a terminal 60, and a housing 80. The stator 50 is made of metal and will be described in detail later. The coil 30 is wound around each tooth of the stator 50. The coil 30 is electrically connected to the printed circuit board PB via the terminal 60, which is non-conductively supported by the stator 50. Components for controlling the energization state of the coil 30 are mounted on the printed circuit board PB.

[0025] The rotor 40 includes a rotating shaft 42, a yoke 44, and one or more permanent magnets 46. The rotating shaft 42 is rotatably supported and extends through a housing 80. Specifically, the rotating shaft 42 is rotatably supported by a bearing BB held in the housing 80. The yoke 44 is fixed to the rotating shaft 42 outside the housing 80 and is substantially cylindrical and made of metal. The housing 80 includes a generally cylindrical columnar portion 81 and a disc-shaped flange portion 85 at the end of the columnar portion 81 on the printed circuit board PB side. The outer diameter of the flange portion 85 is larger than that of the columnar portion 81. The terminal 60 extends through the flange portion 85 via a rubber seal SR. Furthermore, the terminal 60 extends through an outlet provided in the printed circuit board PB and is electrically connected to the printed circuit board PB via a conductive member 65. One or more permanent magnets 46 are fixed to the inner circumferential surface of the yoke 44. The permanent magnets 46 face the outside of the teeth of the stator 50. When the coil 30 is energized, the teeth of the stator 50 are excited, whereby magnetic attraction and repulsion act between the permanent magnet 46 and the teeth, and the yoke 44 (i.e., the rotor 40) rotates relative to the stator 50. As described above, the motor M is an outer rotor type motor in which the rotor 40 rotates.

[0026] Figure 2 This is a perspective view of the outer periphery of the printed circuit board PB with the housing 20 removed. The printed circuit board PB is secured to the housing 10 with screws PS at a predetermined distance from the flange 85. Terminals 60 extend through the outlet opening of the printed circuit board PB, and one end of a conductive member 65 is soldered to one end of the terminal 60. The other end of the conductive member 65 is electrically connected to the conductive pattern of the printed circuit board PB. Furthermore, a connector C is mounted on the printed circuit board PB. A ground bus bar 90 is arranged between the housing 10 and the printed circuit board PB, specifically, between the flange 85 and the printed circuit board PB.

[0027] Figure 3 1 is a perspective view of the outer periphery of the ground bus bar 90 with the printed circuit board PB removed. One end of the ground bus bar 90 is conductively fixed to the bottom surface of the flange portion 85 by a screw S9. Figure 2As shown, the other end of the ground bus bar 90 is inserted into the through hole Ph of the printed circuit board PB and is electrically connected to the ground of the printed circuit board PB. The ground bus bar 90 is an elastic metal plate-shaped rod formed by pressing a metal plate and formed to a predetermined thickness so as to be elastically deformed.

[0028] Figures 4A to 5B is an explanatory view of the ground bus bar 90. Note that Figure 5A Shown along Figure 4B The ground bus bar 90 is viewed in the direction of arrow A, and Figure 5B Shown along Figure 4B 1 and 2. Ground bus bar 90 is viewed in the direction of arrow B in FIG. Ground bus bar 90 includes a first connecting portion 91, a first continuous portion 92, a bent portion 93, a second continuous portion 94, a retaining portion 95, and a second connecting portion 96. First continuous portion 92, bent portion 93, second continuous portion 94, and retaining portion 95 correspond to extensions.

[0029] The first connecting portion 91 has a thin disk shape. A hole 91h for the screw S9 to pass through is formed in the center of the first connecting portion 91. The first continuous portion 92 has a linear shape extending from the first connecting portion 91 in a predetermined direction with a constant width. Figure 5B As shown, a step portion 91 d is formed at a boundary between the first connecting portion 91 and the first continuous portion 92 , so that the first continuous portion 92 is slightly higher than the first connecting portion 91 .

[0030] The bent portion 93 is continuous with the first continuous portion 92 in a different direction, and is bent at approximately 90 degrees with respect to the first continuous portion 92 and the second continuous portion 94 . Figure 4A and Figure 4B A bending line L93 of the curved portion 93 is shown. The bending line L93 is located on a boundary line between the first continuous portion 92 and the curved portion 93 and a boundary line between the second continuous portion 94 and the curved portion 93. The second continuous portion 94 extends linearly from the curved portion 93 in different directions.

[0031] The retaining portion 95 extends linearly from the second continuous portion 94 in the same direction with a constant width. The retaining portion 95 is provided with a protruding edge 95a, a coupling member 95b, an assembly hole 95c, and an engagement hole 95d in sequence from the second continuous portion 94. The two protruding edges 95a slightly protrude outward from the edges on both sides of the retaining portion 95 and extend parallel to the longitudinal direction of the retaining portion 95. The two engagement members 95b extend upwardly at an angle from the edges on both sides of the retaining portion 95. Specifically, the two engagement members 95b extend upwardly at an angle so that their ends are spaced apart from each other compared to their roots. The ends of the engagement members 95b are formed in a valley shape, but are not limited to this. The assembly hole 95c has a circular shape, but is not limited to this. The engagement hole 95d has a rectangular shape, but is not limited to this. The second connecting portion 96 bends upward from the retaining portion 95 and extends linearly. The engagement hole 95d is formed at the boundary between the retaining portion 95 and the second connecting portion 96.

[0032] like Figure 3 As shown, the protruding edge 95a and the engaging member 95b are engaged with the recess 15a provided near the flange portion 85 of the housing 10. The recess 15a has two facing walls, and the protruding edge 95a and the engaging member 95b are engaged between the two walls. Specifically, the protruding edge 95a contacts near the root of the inner surface of one of the two facing walls of the recess 15a. A recess that engages with the end of the engaging member 95b is formed on the inner surface side of the recess 15a. Specifically, the engaging member 95b is accommodated in the recess 15a in a state of elastic deformation of the two walls of the recess 15a, so that the ends of the two engaging members 95b are close to each other. The two engaging members 95b push the two walls of the recess 15a so as to separate from each other by their elastic restoring force. Thus, the engaging member 95b is maintained so as not to fall off from the recess 15a.

[0033] A columnar fitting protrusion 15c is provided near recess 15a of housing 10. Fitting protrusion 15c fits into fitting hole 95c. Furthermore, a rectangular parallelepiped-shaped engaging protrusion 15d provided near fitting protrusion 15c of housing 10 engages with engaging hole 95d. In this manner, retaining portion 95 is secured to housing 10, and displacement of ground bus bar 90 relative to housing 10 is suppressed.

[0034] The second connecting portion 96, which corresponds to so-called press fitting, includes a protruding portion 96a and two protruding portions 96b that sandwich the protruding portion 96a in the width direction. The protruding portion 96a protrudes to one side of the second connecting portion 96 in the thickness direction, and the protruding portions 96b protrude to the opposite side of the second connecting portion 96 in the thickness direction. The protruding portion 96a is elastically deformable in a direction opposite to the protruding direction of the protruding portion 96a. Likewise, the protruding portions 96b are elastically deformable in a direction opposite to the protruding direction of the protruding portions 96b. In the width direction of the second connecting portion 96, there is a gap between the protruding portion 96a and one of the two protruding portions 96b. There is also a gap between the protruding portion 96a and the other of the two protruding portions 96b. That is, the total width of the protruding portion 96a and the two protruding portions 96b is smaller than the width of the entire second connecting portion 96. That is, each of the widths of the protruding portions 96a and 96b is small. As a result, the protruding portions 96a and 96b are easily elastically deformable. The end portion of the second connecting portion 96 has a semicircular thin plate shape.

[0035] Next, the work of assembling the ground busbar 90 and the printed circuit board PB will be described. Figures 6 to 8 is an explanatory view of the work of assembling the ground busbar 90 and the printed circuit board PB. First, as shown in Figure 3 , the fitting hole 95c and the engaging hole 95d are inserted into the fitting protrusion 15c and the engaging protrusion 15d, respectively, and the protruding edge 95a and the engaging piece 95b of the ground busbar 90 are inserted and held between the two wall portions of the recess 15a. In order to hold the holding portion 95 of the ground busbar 90 in the housing 10 in this way, no special jig or the like is required. This improves the assembly workability.

[0036] Next, the first connecting portion 91 is fixed to the flange portion 85 with the screw S9. Next, the terminals 60 are inserted into the through holes of the printed circuit board PB, and the second connecting portion 96 is inserted into the through hole Ph of the printed circuit board PB, thereby placing the printed circuit board PB above the ground busbar 90. Here, the protruding portions 96a and 96b of the second connecting portion 96 push the inner surfaces of the through hole Ph by the elastic restoring force. Therefore, the protruding portions 96a and 96b are electrically connected to the raised portions exposed to the inner surfaces of the through hole Ph. In this way, even when the second connecting portion 96 and the ground of the printed circuit board PB are electrically connected, no fixing member such as a screw is required, which improves the assembly workability.

[0037] Next, a confirmation test of the electrical connection between the printed circuit board PB and the ground busbar 90 is performed. When there is no problem, as Figure 6As shown, one end of the conductive member 65, the other end of which has been attached to the printed circuit board PB, is soldered to the end of the terminal 60. Next, a confirmation test of the electrical connection between the printed circuit board PB and the conductive member 65 is performed. When there is no problem, the printed circuit board PB is fixed to the housing 10 with the screw PS, as shown in FIG. Figure 7 Afterwards, the housing 20 is assembled to the housing 10 . Figure 8 1 is a cross-sectional view showing the periphery of the ground bus bar 90 and the printed circuit board PB after the housing 20 is assembled to the housing 10 .

[0038] For example, in a confirmation test of the electrical connection between the second connection portion 96 and the ground of the printed circuit board PB, when there is any abnormality in the printed circuit board PB, the printed circuit board PB is easily removed from the ground bus bar 90. This also improves the workability of replacing the printed circuit board PB.

[0039] Next, the vibration absorption of the grounding bus bar 90 will be described. In the blower device A, the vibration of the motor M is also transmitted to the grounding bus bar 90. Here, the vibration of the motor M mainly includes the vibration in the direction of the central axis of the rotating shaft 42 and the vibration in the circumferential direction about the central axis of the rotating shaft 42. For example, Figure 4A As shown, when the flange portion 85 vibrates in the axial direction AD of the rotation shaft 42, the first connection portion 91 is fixed to the flange portion 85, so that the vibration in the axial direction AD can be transmitted from the first connection portion 91 to the second connection portion 96. This may affect the electrical connection between the second connection portion 96 and the through hole Ph.

[0040] However, in this embodiment, the bending line L93 of the bent portion 93 intersects the radial direction RD with respect to the central axis of the rotation shaft 42, as shown in FIG. Figure 4B As shown, specifically, the bending line L93 is substantially orthogonal to the radial direction RD. Therefore, vibrations of the first connecting portion 91 in the axial direction AD are absorbed by elastic deformation of the first continuous portion 92 relative to the curved portion 93 about the bending line L93, and by elastic deformation of the curved portion 93 relative to the second continuous portion 94 about the bending line L93. This suppresses the transmission of vibrations to the second connecting portion 96.

[0041] like Figure 4B As shown, the length L94 of the second continuous portion 94 is formed to be longer than the length L92 of the first continuous portion 92, and the second continuous portion 94 and the first continuous portion 92 have the same thickness and width. Therefore, the second continuous portion 94 is more easily bent than the first continuous portion 92. In addition, the second continuous portion 94 is along the circumferential direction CD about the central axis of the rotation shaft 42. Therefore, in the second continuous portion 94, vibration in the circumferential direction CD is absorbed by the slight bending of the second continuous portion 94.

[0042] Furthermore, even if the vibration of the motor M is transmitted to the first connecting portion 91, the first continuous portion 92, the bent portion 93, and the second continuous portion 94 in this order, the holding portion 95 is held by the housing 10. Therefore, the vibration of the holding portion 95 relative to the housing 10 is suppressed. Figure 4B As shown, the retaining portion 95 is closer to the second connecting portion 96 than the first connecting portion 91. Therefore, since the retaining portion 95 is held by the housing 10 at a position close to the second connecting portion 96, it is possible to suppress any vibration of the second connecting portion 96 relative to the housing 10. Consequently, it is possible to suppress any vibration of the second connecting portion 96 relative to the through-hole Ph of the printed circuit board PB fixed to the housing 10. Thus, electrical connection between the second connecting portion 96 and the printed circuit board PB is ensured.

[0043] Figure 9 The figure is an enlarged view of the through-hole Ph into which the second connecting portion 96 is inserted. The through-hole Ph has an elongated hole shape extending in the radial direction RD and has linear long edges Pha and Phb facing each other. In other words, the long edges Pha and Phb extend to intersect the circumferential direction CD. The protrusions 96a and 96b push against the long edges Pha and Phb, respectively. For example, even when vibration in the circumferential direction CD is transmitted to the second connecting portion 96, the protrusions 96a and 96b elastically deform in the circumferential direction CD, constantly pushing and following the long edges Pha and Phb. This ensures electrical connection between the second connecting portion 96 and the printed circuit board PB.

[0044] like Figure 9 As shown, two protrusions 96b are arranged to sandwich the protrusion 96a from the longitudinal direction of the through hole Ph. In this way, the second connecting portion 96 is connected to the inner surface of the through hole Ph at a total of three points. This ensures electrical connection between the second connecting portion 96 and the printed circuit board PB.

[0045] In addition, if Figure 9 As shown, both long edges Pha and Phb have a linear shape, and protrusions 96a and 96b are in surface contact with long edges Pha and Phb, respectively. Therefore, even if vibration in the radial direction RD is transmitted to the second connecting portion 96 and the second connecting portion 96 is displaced in the longitudinal direction within the through-hole Ph, this surface contact is maintained. This ensures electrical connection between the second connecting portion 96 and the printed circuit board PB.

[0046] Figure 10 is an enlarged view of the second connecting portion 96 . Figure 10The printed circuit board PB is shown in the process of inserting the second connection portion 96 into the through hole Ph. The protrusion 96a has a root inclined portion 96a1, a flat portion 96a2, and an end inclined portion 96a3 in sequence from the retaining portion 95. Similarly, the protrusion 96b has a root inclined portion 96b1, a flat portion 96b2, and an end inclined portion 96b3 in sequence from the retaining portion 95. The root inclined portions 96a1 and 96b1 are inclined in opposite directions from the retaining portion 95. The flat portions 96a2 and 96b2 extend parallel to each other. The end inclined portions 96a3 and 96b3 are inclined so as to approach each other from the flat portions 96a2 and 96b2, respectively. As shown in FIG. Figure 10 As shown, before printed circuit board PB is assembled to ground busbar 90, distance T9 between flat portions 96a2 and 96b2 in the thickness direction is longer than length Th in the lateral direction of through-hole Ph. Therefore, protrusions 96a and 96b are inserted into through-hole Ph. With flat portions 96a2 and 96b2 in contact with long edges Pha and Phb, respectively, the elastic restoring forces of protrusions 96a and 96b are applied to long edges Pha and Phb. Consequently, flat portions 96a2 and 96b2 push against long edges Pha and Phb, respectively.

[0047] In addition, if Figure 10 As shown, the angle α3 of the end inclined portion 96a3 relative to the flat portion 96a2 is smaller than the angle α1 of the base inclined portion 96a1 relative to the flat portion 96a2, and the angle β3 of the end inclined portion 96b3 relative to the flat portion 96b2 is smaller than the angle β1 of the base inclined portion 96b1 relative to the flat portion 96b2. Therefore, when the second connecting portion 96 is inserted into the through-hole Ph, it easily elastically deforms, causing the end inclined portions 96a3 and 96b3 to contact and be compressed with the long edges Pha and Phb, respectively. This improves assembly workability.

[0048] In the above embodiment, the motor device is described as being integrated into the blower device A, but the present invention is not limited to this motor device. The motor device may be integrated into the pump device, or a separate motor device. In addition, in the above embodiment, an outer rotor type motor is described as an example, but the present invention is not limited to this, and an inner rotor type motor may also be used.

[0049] Although the exemplary embodiments of the present invention have been described in detail, the present invention is not limited to the above-described embodiments, and other embodiments, variations, and changes may be made without departing from the scope of the present invention.

Claims

1. A motor device, comprising: Motor body; a housing accommodating the motor body; a printed circuit board that controls driving of the motor body and is supported by the housing; as well as a ground bus bar disposed between the motor body and the printed circuit board and connecting grounds of the motor body and the printed circuit board, in, The grounding busbar is an elastic metal plate-shaped rod. The ground bus bar comprises: a first connecting portion fixed to the motor body; a second connection portion fixed to the printed circuit board; and an extension portion extending from the first connection portion to the second connection portion, The printed circuit board includes a through hole for a ground connection, The first connection portion is screwed to the motor body, and The second connection portion is inserted into the through hole and elastically deformed to engage with the through hole, Wherein, the second connecting portion includes a first protruding portion and a second protruding portion, The first protrusion and the second protrusion are elastically deformable and protrude in opposite directions. The through hole is formed in a long hole shape, The through hole comprises a first long edge and a second long edge, The first long edge and the second long edge extend in the longitudinal direction of the through hole and face each other, and The first protrusion and the second protrusion push the first long edge and the second long edge respectively according to the elastic restoring force of the first protrusion and the second protrusion, Wherein, two of the second protrusions clamp the first protrusion in the longitudinal direction.

2. The motor device according to claim 1, wherein The first long edge and the second long edge extend in a radial direction of a central axis of the motor body, and The first and second protrusions are elastically deformable in a circumferential direction about the center axis of the motor body.

3. The motor device according to claim 1, wherein The extension portion includes a retaining portion, and The holding portion is located between the first connecting portion and the second connecting portion and is held by the housing.

4. The motor device according to claim 3, wherein: The holding portion includes a first engaging member and a second engaging member, The first engaging member and the second engaging member are elastically deformable, The housing comprises a recess comprising two walls facing each other, and The holding portion is held in a state where the first engaging member and the second engaging member are elastically deformed between the two wall portions.

5. The motor device according to claim 3, wherein The holding portion is closer to the second connecting portion than to the first connecting portion.

6. The motor device according to claim 3, wherein The extension portion comprises: a first continuous portion extending from the first connecting portion in a radial direction of the motor body; a second continuous portion extending to an opposite side of the second connecting portion and extending from the retaining portion in a circumferential direction of the motor body; and a curved portion, the curved portion being continuous between the first continuous portion and the second continuous portion, The first continuous portion, the second continuous portion, and the bent portion are not fixed to the motor body or the housing, The bent portion is bent to stand upright relative to the first continuous portion and the second continuous portion, and A boundary line between the bent portion and the first continuous portion and a boundary line between the bent portion and the second continuous portion intersect with the radial direction with respect to a central axis of the motor body.

7. The motor device according to claim 6, wherein: The first continuous portion extends in the radial direction with respect to the central axis of the motor body, The second continuous portion extends in the circumferential direction of the central axis of the motor body, and A length of the second continuous portion in a direction in which the second continuous portion extends is greater than a length of the first continuous portion in the direction in which the first continuous portion extends.

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