JP2017208918A - Brushless motor and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit vibration of a circuit board and secure airtightness of a space formed by a case and a plate part in a brushless motor.SOLUTION: A first joint part 101 is formed at an outer edge part of a plate part 51 of a center piece 50, and a second joint part 102 joined to the first joint part 101 is formed at an outer edge part of a case 70 which houses a circuit board 60. A first protrusion part 103 is formed at an inner side of the outer edge part of the plate part 51, and a second protrusion part 104, which sandwiches the circuit board 60 with the first protrusion part 103, is formed at an inner side of the outer edge part of the case 70. A first contact part 105 extending along the outer edge part of the plate part 51 is formed at an area in the plate part 51 which is located between the first joint part 101 and the first protrusion part 103. A second contact part 106 extending along the outer edge part of the case 70 and placed in contact with the first contact part 105 is formed at an area in the case 70 which is located between the second joint part 102 and the second protrusion part 104.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a brushless motor and a method for manufacturing the brushless motor.

  Conventionally, as a brushless motor, an annular stator, a center piece having a plate portion facing the stator in the axial direction of the stator, a circuit board provided on the opposite side of the stator to the plate portion, and a plate substrate (For example, refer to patent document 1).

Japanese Patent Laid-Open No. 11-275833

  In the above brushless motor, when the circuit board vibrates, there is a possibility that abnormal noise may be generated or the circuit board may be damaged. Therefore, it may be required that vibration of the circuit board can be suppressed. Further, in the brushless motor, in order to ensure the waterproofness of the circuit board or to prevent the sound from leaking from the inside of the case to the outside, it is possible to ensure the sealing property of the space formed by the case and the plate portion. May be required.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a brushless motor capable of suppressing vibration of a circuit board and ensuring airtightness of a space formed by a case and a plate portion. To do.

  In order to achieve the object, the brushless motor according to claim 1 is an annular stator, a center piece having a plate portion facing the stator in an axial direction of the stator, and opposite to the stator with respect to the plate portion. A circuit board provided on the side, a case for accommodating the circuit board by the plate portion, a first joint formed at an outer edge portion of the plate portion, and an outer edge portion of the case, A second joining part joined to one joining part, a first clamping part formed inside the outer edge part of the plate part, and an inner side than the outer edge part of the case, the first clamping part; The first holding portion is formed between the second holding portion for holding the circuit board, the first joint portion and the first holding portion of the plate portion, and extends along the outer edge portion of the plate portion. Is formed between the second joint portion and the second clamping portion in the case, and extends along the outer edge portion of the case and is in contact with the first contact portion. A contact portion.

  According to this brushless motor, the first clamping part is formed inside the outer edge part of the plate part, and the second clamping part is formed inside the outer edge part of the case. And the circuit board is clamped by the 1st clamping part and the 2nd clamping part. Therefore, since the support rigidity of the circuit board can be secured by the first clamping part and the second clamping part, vibration of the circuit board can be suppressed.

  Further, a first contact portion extending along the outer edge portion of the plate portion is formed between the first joint portion and the first sandwiching portion in the plate portion, and the second joint portion and the second sandwiching portion in the case are formed. A second contact portion extending along the outer edge portion of the case is formed between the two portions. The first contact portion and the second contact portion are in contact with each other. Therefore, since the space between the first contact portion and the second contact portion is sealed, the airtightness of the space formed by the case and the plate portion can be ensured.

  In addition, as described in claim 2, in the brushless motor according to claim 1, the first sandwiching portion is a first projecting portion extending from the plate portion toward the circuit board, and the second sandwiching portion. The portion may be a second protrusion extending from the case toward the circuit board.

  According to this brushless motor, the first clamping part and the second clamping part are formed by the first and second projections, respectively, so that a circuit is formed by the first projection and the second projection. The substrate can be sandwiched locally. Thereby, the mounting area of a circuit board is securable.

  Further, as described in claim 3, in the brushless motor according to claim 2, the portion of the case between the second protrusion and the second contact portion is a fulcrum of the second protrusion. The portion between the second contact portion and the second joint portion in the case is elastically deformed toward the plate portion side, with the second contact portion serving as a fulcrum to the plate portion side. It may be elastically deformed.

  According to this brushless motor, by joining the first joint portion and the second joint portion, the portion between the second projection portion and the second contact portion in the case has the second projection portion as a fulcrum, While being elastically deformed to the plate portion side, a portion of the case between the second contact portion and the second joint portion is elastically deformed to the plate portion side with the second contact portion as a fulcrum. Accordingly, since the second protrusion and the second contact portion are pressed against the circuit board and the first contact portion by these elastic deformations, respectively, the support rigidity of the circuit board and the first contact portion and the first contact portion are The sealing performance between the two contact portions can be improved.

  Moreover, as described in claim 4, in the brushless motor according to claim 3, the second protrusion is located on the opposite side of the second contact with respect to the first protrusion. Also good.

  According to this brushless motor, the second protrusion is located on the opposite side of the second protrusion with respect to the first protrusion, so that it is sufficient between the second protrusion and the second contact in the case. A large deformation allowance (deformable length) can be secured. Thereby, the part between the 2nd projection part in the case and the 2nd contact part can be elastically deformed exactly to the plate part side by using the 2nd projection part as a fulcrum.

  Further, as in claim 5, in the brushless motor according to claim 4, the first protrusion is closer to the end of the circuit board than the second protrusion. May be located in

  According to this brushless motor, since the first protrusion is located closer to the end of the first contact portion on the circuit board than the second protrusion, the first protrusion is connected to the first contact on the circuit board. It can be located at the end side of the part side, that is, toward the end of the circuit board. Thereby, for example, interference between the component mounted on the circuit board and the first protrusion can be suppressed.

  In addition, as described in claim 6, in the brushless motor according to any one of claims 1 to 5, the circuit board includes a heat sink, and the first clamping unit and the second clamping unit are provided. The portion may sandwich the heat sink.

  According to this brushless motor, since the first clamping unit and the second clamping unit clamp the heat sink of the circuit board, vibration of the heavy heat sink can be suppressed. Thereby, the vibration of the circuit board can be more effectively suppressed.

  In order to achieve the above object, a method of manufacturing a brushless motor according to claim 7, wherein a plate portion of a center piece is opposed to an annular stator in an axial direction of the stator, and the plate portion is opposed to the plate portion. A circuit board is provided on the opposite side of the stator and the circuit board is accommodated by the plate part and the case; a first joint part formed on the outer edge part of the plate part; and an outer edge of the case A first clamping part formed inside the outer edge part of the plate part, and a second clamping part formed inside the outer edge part of the case And the first contact portion formed between the first joint portion and the first sandwich portion in the plate portion, the second joint portion in the case, and the second And a present assembling step of abutting a second abutment portion formed between the sandwiching member.

  According to this method of manufacturing a brushless motor, the circuit board is sandwiched between the first clamping part formed inside the outer edge part of the plate part and the second clamping part formed inside the outer edge part of the case. To do. Therefore, since the support rigidity of the circuit board can be secured by the first clamping part and the second clamping part, vibration of the circuit board can be suppressed.

  Further, a first contact portion that is formed between the first joint portion and the first sandwiching portion in the plate portion and extends along the outer edge portion of the plate portion, and the second joint portion and the second sandwiching portion in the case A second abutting portion that is formed therebetween and extends along the outer edge portion of the case abuts on each other. Therefore, since the space between the first contact portion and the second contact portion is sealed, the airtightness of the space formed by the case and the plate portion can be ensured.

  In addition, as described in claim 8, in the temporary assembly step in the method of manufacturing the brushless motor according to claim 7, the circuit board is sandwiched between the first sandwiching section and the second sandwiching section. Then, the gap dimension G1 between the first joint part and the second joint part and the gap dimension G2 between the first contact part and the second contact part are G1 ≧ 0, G2 ≧ 0 and G1 ≧ G2 may be satisfied.

  According to this method of manufacturing a brushless motor, in the temporary assembly process, in a state where the circuit board is sandwiched between the first sandwiching portion and the second sandwiching portion, the gap dimension between the first joint portion and the second joint portion. G1 and the gap dimension G2 between the first contact portion and the second contact portion satisfy G1 ≧ 0, G2 ≧ 0, and G1 ≧ G2. Therefore, in this assembly process, when the first joint formed on the outer edge of the plate portion and the second joint formed on the outer edge of the case are joined, the first protrusion and the second The protrusion can reliably contact the circuit board, and the first contact portion and the second contact portion can reliably contact each other.

  In particular, when G1> 0, G2> 0, and G1> G2, the portion between the second protrusion and the second contact portion in the case is moved to the plate portion side with the second protrusion as a fulcrum. While being able to elastically deform, the part between the 2nd contact part and 2nd junction part in a case can be elastically deformed to the plate part side by using the 2nd contact part as a fulcrum. As a result, the second protrusion and the second abutment are pressed against the circuit board and the first abutment by the elastic deformation, respectively. The sealing property between the second contact portion and the second contact portion can be improved.

It is a front view including the partial cross section of the brushless motor which concerns on one Embodiment of this invention. It is the principal part expanded sectional view which showed typically the plate part of the centerpiece shown by FIG. 1, a circuit board, and the decomposition | disassembly state of a case. It is a figure which shows the assembly | attachment state in case the gap dimensions G1 and G2 shown by FIG. 2 are G1 = G2 = 0. It is a figure explaining the case where the gap dimensions G1 and G2 shown by FIG. 2 are G1> 0, G2> 0, G1> G2. It is a figure which shows the modification which replaced the position of the 1st projection part shown in FIG. 2, and the 2nd projection part. FIG. 3 is a diagram illustrating a case where a gap dimension G2 shown in FIG. 2 is G2 <0 as a first comparative example. FIG. 6 is a diagram illustrating a case where gap dimensions G1 and G2 shown in FIG. 2 are 0 <G1 <G2 as a second comparative example.

  Hereinafter, an embodiment of the present invention will be described.

  As shown in FIG. 1, a brushless motor 10 according to an embodiment of the present invention includes a motor shaft 12, a stator 20, a rotor 30, a bearing holder 40, a center piece 50, a circuit board 60, and a case. 70 and a cover 80. In FIG. 1, an arrow A <b> 1 indicates one axial direction of the brushless motor 10, and an arrow A <b> 2 indicates the other axial direction of the brushless motor 10.

  The stator 20 includes a stator core 21, an insulator 22, and a plurality of windings 23. The stator core 21 has a plurality of teeth portions 24 extending radially. The insulator 22 is attached to the surface of the stator core 21, and the winding 23 is wound around each tooth portion 24 via the insulator 22. The entire stator 20 including the stator core 21 has an annular shape around the axial direction of the motor shaft 12. Antivibration rubber 25 is attached to appropriate portions in the circumferential direction of the inner peripheral portion of the stator core 21. The stator 20 forms a rotating magnetic field in the circumferential direction.

  The rotor 30 includes a rotor housing 31 and a rotor magnet 32. The rotor housing 31 is formed in a cylindrical shape having a peripheral wall portion 33 and a top wall portion 34 and accommodates the stator 20. The motor shaft 12 is press-fitted inside the cylindrical portion 35 formed at the center of the top wall portion 34, whereby the rotor housing 31 is fixed to the motor shaft 12 so as to be integrally rotatable. The rotor magnet 32 is fixed to the inner peripheral surface of the peripheral wall portion 33, and is disposed opposite to the stator 20 on the radially outer side of the stator 20.

  The bearing holder 40 has a holder part 41 and a cylindrical part 42. The holder part 41 is formed in an annular shape having a larger diameter than the cylindrical part 42, and is positioned on one side in the axial direction of the cylindrical part 42. A first bearing 45 that is a ball bearing is press-fitted inside the holder portion 41. The motor shaft 12 is press-fitted inside the inner ring of the first bearing 45, and the motor shaft 12 is inserted inside the cylindrical portion 42.

  The center piece 50 has a plate portion 51 and a shaft portion 52. The plate portion 51 is formed in a substantially flat plate shape in which the axial direction of the motor shaft 12 is the plate thickness direction. The plate portion 51 is disposed on the other axial side of the stator 20 so as to face the stator 20. The shaft portion 52 protrudes from the center portion of the plate portion 51 toward the stator 20 and is inserted inside the stator 20. The shaft portion 52 is formed in a substantially cylindrical shape. The cylindrical portion 42 of the bearing holder 40 described above is press-fitted inside the shaft portion 52, whereby the bearing holder 40 is fixed to the center piece 50.

  The shaft portion 52 is formed with a pedestal portion 53 located on the other axial side of the stator 20. The holder portion 41 and the pedestal portion 53 sandwich the anti-vibration rubber 25 from both axial sides of the stator 20, whereby the stator 20 is held by the center piece 50 via the anti-vibration rubber 25. On the opposite side of the central portion of the plate portion 51 from the shaft portion 52, a concave accommodating portion 54 is formed that opens to the opposite side to the side from which the shaft portion 52 protrudes.

  A second bearing 55 that is a ball bearing is press-fitted inside the accommodating portion 54. The motor shaft 12 is press-fitted inside the inner ring of the second bearing 55. The motor shaft 12 is rotatably supported by the bearing holder 40 and the center piece 50 by the second bearing 55 and the first bearing 45 described above.

  The circuit board 60 drives the stator 20 and is arranged on the opposite side of the plate portion 51 from the stator 20. A plurality of electronic components are mounted on the circuit board 60. The plurality of electronic components include, for example, a switching element that is electrically connected to the plurality of windings 23 and switches the direction of current flowing through the plurality of windings 23, a control element that controls the switching operation of the switching elements, and the like. Is included.

  When the direction of the current flowing through the plurality of windings 23 is switched, a rotating magnetic field is formed by the stator 20. Further, an attractive and repulsive force acts on the rotor magnet 32 in accordance with the rotating magnetic field, whereby the rotor 30 rotates together with the motor shaft 12.

  The case 70 is disposed on the side opposite to the stator 20 with respect to the plate portion 51 and is assembled to the plate portion 51. The case 70 is formed in a substantially concave shape that opens to the plate portion 51 side, and accommodates the circuit board 60 with the plate portion 51.

  The cover 80 is disposed on the side opposite to the case 70 with respect to the plate portion 51, and is assembled with the plate portion 51 and the case 70. The cover 80 is formed in a substantially concave shape that opens toward the plate portion 51, and accommodates the rotor 30 with the plate portion 51.

  Next, the main part of the plate part 51, the circuit board 60, and the case 70 of the center piece 50 described above will be described.

  FIG. 2 schematically shows an exploded state of the plate portion 51, the circuit board 60, and the case 70 of the center piece 50 shown in FIG. A first joint portion 101 is formed at the outer edge portion of the plate portion 51, and a second joint portion 102 to be joined to the first joint portion 101 is formed at the outer edge portion of the case 70. The first joint portion 101 and the second joint portion 102 are formed to face the plate portion 51 and the case 70 in the facing direction. Moreover, the mutual joining surface in the 1st junction part 101 and the 2nd junction part 102 is formed in planar shape. For example, the first joint 101 and the second joint 102 are joined by screws and nuts (not shown).

  Further, a first protrusion 103 that is an example of the “first clamping portion” in the present invention is formed on the inner side (arrow IN side) of the outer edge of the plate portion 51, and is more than the outer edge of the case 70. On the inner side, a second protrusion 104 that is an example of the “second clamping portion” in the present invention is formed. The first protrusion 103 and the second protrusion 104 are for sandwiching the circuit board 60, and the first protrusion 103 extends from the plate part 51 toward the circuit board 60, and the second protrusion 104 Extends from the case 70 toward the circuit board 60. The first protrusion 103 and the second protrusion 104 extend linearly along the opposing direction of the plate 51 and the case 70. More specifically, the circuit board 60 has a heat sink 61, and the first protrusion 103 and the second protrusion 104 sandwich the heat sink 61 of the circuit board 60.

  Further, a first contact portion 105 extending along the outer edge portion of the plate portion 51 is formed between the first joint portion 101 and the first projection portion 103 in the plate portion 51, and the second contact in the case 70 is formed. A second contact portion 106 extending along the outer edge portion of the case 70 is formed between the joint portion 102 and the second projection portion 104. The first contact portion 105 and the second contact portion 106 may or may not form an annular shape along the outer edge portion of the plate portion 51 and the outer edge portion of the case 70. The first contact portion 105 and the second contact portion 106 are formed so as to face each other in the facing direction of the plate portion 51 and the case 70. The first contact portion 105 and the second contact portion 106 are in contact with each other.

  The second protrusion 104 is located on the opposite side (arrow IN side) from the second contact part 106 with respect to the first protrusion 103, and the first protrusion 103 is the second protrusion. The circuit board 60 is positioned closer to the end 107 side (on the opposite side to the arrow IN) of the circuit board 60 than the circuit board 60, that is, toward the end of the circuit board 60.

  Next, a method for manufacturing the above-described brushless motor will be described.

  The manufacturing method of the brushless motor according to the present embodiment includes a temporary assembly process and a main assembly process in order to assemble the plate portion 51, the circuit board 60, and the case 70 of the center piece 50 described above.

  In the temporary assembly step, the plate portion 51 of the center piece 50 is opposed to the stator 20 in the axial direction of the stator 20, the circuit board 60 is provided on the opposite side of the stator 20 from the plate portion 51, and the plate portion 51 is provided. The circuit board 60 is accommodated in the case 70.

  Subsequently, in the assembly process, the first joint 101 and the second joint 102 are joined, the circuit board 60 is sandwiched between the first projection 103 and the second projection 104, and the first The contact portion 105 and the second contact portion 106 are brought into contact with each other. And the 1st junction part 101 and the 2nd junction part 102 are joined by the screw and nut which are not shown in figure, for example.

  In addition to the plate portion 51, the circuit board 60, and the case 70 of the center piece 50 described above, the members shown in FIG. 1 are assembled in an appropriate order.

  Next, the dimension setting of each part in the plate part 51 of the above-mentioned centerpiece 50, the circuit board 60, and the case 70 will be described.

  2, G1, G2, H1, H2, C1, C2, and F are all dimensions along the opposing direction of the plate portion 51 and the case 70. Specifically, G1 and G2 are gaps between the first joint portion 101 and the second joint portion 102 when the first projection portion 103 and the second projection portion 104 are in contact with the circuit board 60. The size of the gap between the first contact portion 105 and the second contact portion 106.

  H1 is a height dimension between the joint surface of the first joint portion 101 with the second joint portion 102 and the tip surface of the first projection portion 103, and H2 is at the first contact portion 105. It is a height dimension between the contact surface with the second contact portion 106 and the joint surface with the second joint portion 102 in the first joint portion 101.

  Further, C1 is a height dimension between the joint surface of the second joint portion 102 with the first joint portion 101 and the tip surface of the second projection portion 104, and C2 is the first dimension at the second joint portion 102. This is the height dimension between the joint surface with the one joint portion 101 and the tip surface of the second contact portion 106.

  F is a thickness dimension of the circuit board 60 (heat sink 61) at a position sandwiched between the first protrusion 103 and the second protrusion 104.

  For G1, G2, H1, H2, C1, C2, and F described above, the following expressions (1) and (2) are established.

F + H1-C1 = G1 (1)
F + H1 + H2-C2-C1 = G2 (2)

  Here, FIG. 6 shows a case where the gap dimension G2 shown in FIG. 2 is G2 <0. As shown in the upper diagram of FIG. 6, when G2 <0 is calculated, the first contact portion 105 and the second contact portion 106 are brought into contact with each other as shown in the lower diagram of FIG. 6. In the actually assembled state, the first protrusion 103 and the second protrusion 104 are separated from the circuit board 60. Therefore, when G2 <0, the circuit board 60 cannot be sandwiched between the first protrusion 103 and the second protrusion 104. Therefore, in order to hold the circuit board 60 between the first protrusion 103 and the second protrusion 104, it is required that G2 ≧ 0.

  FIG. 7 shows a case where the gap dimensions G1 and G2 shown in FIG. 2 are 0 <G1 <G2. In this case, since G1> 0 and G2> 0, the first protrusion 103 and the second protrusion 104 come into contact with the circuit board 60 as shown in the upper diagram of FIG. And the circuit board 60 can be clamped by the second protrusion 104.

  However, since G1 <G2, as shown in the lower diagram of FIG. 7, in the state where the first joint portion 101 and the second joint portion 102 are joined together and actually assembled, The two contact portions 106 are separated from each other. Therefore, when G1 <G2, the gap between the first contact portion 105 and the second contact portion 106 cannot be sealed. Therefore, in order to seal between the first contact portion 105 and the second contact portion 106, it is required that G1 ≧ G2.

  On the other hand, FIG. 3 shows an assembled state when the gap dimensions G1 and G2 shown in FIG. 2 are G1 = G2 = 0. As described above, when G1 = G2 = 0, the first protrusion 103 and the second protrusion 104 are in contact with the circuit board 60, and the first contact 105 and the second contact 106 are in contact with each other. Abut. Therefore, the circuit board 60 can be held between the first protrusion 103 and the second protrusion 104, and the space between the first contact part 105 and the second contact part 106 can be sealed.

  FIG. 4 shows a case where the gap dimensions G1 and G2 shown in FIG. 2 are G1> 0, G2> 0, and G1> G2. When G1> 0 and G2> 0, as shown in the upper diagram of FIG. 4, when the first protrusion 103 and the second protrusion 104 are in contact with the circuit board 60, the first contact portion While 105 and the 2nd contact part 106 leave | separate, the 1st junction part 101 and the 2nd junction part 102 will be in the separated state.

  However, since G1> G2, as shown in the lower diagram of FIG. 4, in the state where the first joint portion 101 and the second joint portion 102 are joined to each other and actually assembled, The two contact portions 106 are in contact with each other. Therefore, the circuit board 60 can be held between the first protrusion 103 and the second protrusion 104, and the space between the first contact part 105 and the second contact part 106 can be sealed.

  When G1> G2, the first contact portion 105 and the second contact portion 106 contact each other before the first joint portion 101 and the second joint portion 102 are joined to each other. Therefore, the portion 108 between the second protrusion 104 and the second contact portion 106 in the case 70 is elastically deformed toward the plate portion 51 with the second protrusion 104 as a fulcrum, and the second A portion 109 between the contact portion 106 and the second joint portion 102 is elastically deformed toward the plate portion 51 with the second contact portion 106 as a fulcrum. Thereby, the second protrusion 104 and the second contact portion 106 can be pressed against the circuit board 60 and the first contact portion 105 by these elastic deformations, respectively.

  When G1> 0, G2> 0, and G1> G2, it is desirable that the case 70 has a lower rigidity than the plate portion 51 so that the case 70 is elastically deformed with respect to the plate portion 51. For example, the case 70 is made of a material having a lower strength than the plate portion 51, the case 70 is formed thinner than the plate portion 51, or a rib is provided on the case 70. It is possible to reduce the rigidity.

  From the above, the conditions under which the circuit board 60 can be held between the first protrusion 103 and the second protrusion 104 and the space between the first contact part 105 and the second contact part 106 can be sealed are as follows. G1 ≧ 0, G2 ≧ 0, and G1 ≧ G2. Therefore, in the brushless motor and the method of manufacturing the brushless motor in the present embodiment, G1 ≧ 0, G2 ≧ 0, and G1 ≧ G2 are employed. 3 and 4 correspond to one embodiment of the present invention, and FIGS. 6 and 7 correspond to comparative examples for the present embodiment.

  Next, the operation and effect of one embodiment of the present invention will be described.

  As described above in detail, according to the brushless motor according to the embodiment of the present invention, the first protrusion 103 is formed on the inner side of the outer edge portion of the plate portion 51, and the outer edge portion of the case 70. On the inner side, a second protrusion 104 is formed. The circuit board 60 is sandwiched between the first protrusion 103 and the second protrusion 104. Therefore, since the support rigidity of the circuit board 60 can be secured by the first protrusion 103 and the second protrusion 104, vibration of the circuit board 60 can be suppressed.

  Further, a first contact portion 105 extending along the outer edge portion of the plate portion 51 is formed between the first joint portion 101 and the first projection portion 103 in the plate portion 51, and the second contact in the case 70 is formed. A second contact portion 106 extending along the outer edge portion of the case 70 is formed between the joint portion 102 and the second projection portion 104. The first contact portion 105 and the second contact portion 106 are in contact with each other. Therefore, since the space between the first contact portion 105 and the second contact portion 106 is sealed, the airtightness of the space formed by the case 70 and the plate portion 51 can be ensured.

  In addition, since the projecting first projection 103 and the second projection 104 are used to sandwich the circuit board 60, the circuit board 60 is held by the first projection 103 and the second projection 104, respectively. Can be pinched locally. Thereby, the mounting area of the circuit board 60 can be ensured.

  In the temporary assembly step, in the state where the circuit board 60 is sandwiched between the first protrusion 103 and the second protrusion 104, the gap dimension G1 between the first joint 101 and the second joint 102, and The gap dimension G2 between the first contact portion 105 and the second contact portion 106 satisfies G1 ≧ 0, G2 ≧ 0, and G1 ≧ G2. Accordingly, in the present assembly process, when the first joint 101 and the second joint 102 are joined, the first projection 103 and the second projection 104 can be reliably brought into contact with the circuit board 60. At the same time, the first contact portion 105 and the second contact portion 106 can reliably contact each other.

  In particular, as shown in FIG. 4, when G1> 0, G2> 0, and G1> G2, the portion 108 between the second protrusion 104 and the second contact portion 106 in the case 70 is The second protrusion 104 can be used as a fulcrum to be elastically deformed toward the plate portion 51, and the portion 109 between the second contact portion 106 and the second joint portion 102 in the case 70 is replaced with the second contact portion. 106 can be elastically deformed toward the plate portion 51 side with the fulcrum 106 as a fulcrum. As a result, the second protrusion 104 and the second contact portion 106 are pressed against the circuit board 60 and the first contact portion 105, respectively, by these elastic deformations. The sealing performance between the first contact portion 105 and the second contact portion 106 can be improved.

  In addition, since the second protrusion 104 is located on the opposite side (arrow IN side) to the second protrusion 106 with respect to the first protrusion 103, the second protrusion 104 and the second contact in the case 70. A sufficient deformation allowance (deformable length) can be ensured between the terminal 106 and the terminal 106. Thereby, the part 108 between the second protrusion 104 and the second contact part 106 in the case 70 can be elastically deformed accurately toward the plate part 51 with the second protrusion 104 as a fulcrum.

  Further, since the first protrusion 103 is located closer to the end 107 side (on the opposite side to the arrow IN) of the circuit board 60 than the second protrusion 104, the first protrusion 103 is arranged. The circuit board 60 can be positioned at the end 107 side of the first contact part 105 side, that is, toward the end of the circuit board 60. Thereby, for example, interference between a component (for example, a fin of a heat sink) mounted on the circuit board 60 and the first protrusion 103 can be suppressed.

  Moreover, since the 1st projection part 103 and the 2nd projection part 104 are clamping the heat sink 61 of the circuit board 60, it can suppress the vibration of the heat sink 61 which is a heavy article. Thereby, the vibration of the circuit board 60 can be more effectively suppressed.

  Next, a modification of one embodiment of the present invention will be described.

  In the above embodiment, the first protrusion 103 is located closer to the end 107 side (on the opposite side to the arrow IN) of the circuit board 60 than the second protrusion 104, for example, As shown in FIG. 5, when the arrangement position of the first protrusion 103 can be secured on the circuit board 60, the first protrusion 103 is closer to the first protrusion on the circuit board 60 than the second protrusion 104 is. It may be located on the opposite side (arrow IN side) to the end 107 on the contact portion 105 side.

  Moreover, in the said embodiment, although the 1st junction part 101 and the 2nd junction part 102 are joined more preferably by a screw and a nut, you may join by fixing means other than a screw and a nut.

  In the above-described embodiment, preferably, the projecting first protrusion 103 and the second protrusion 104 are used for sandwiching the circuit board 60, but the first sandwiching part and the second projecting part having a shape other than the projecting part are used. The circuit board 60 may be sandwiched between the two sandwiching portions.

  In the above embodiment, preferably, the heat sink 61 of the circuit board 60 is sandwiched between the first protrusion 103 and the second protrusion 104, but the portion other than the heat sink 61 in the circuit board 60 is the first protrusion 103 and It may be clamped by the second protrusion 104.

  Although one embodiment of the present invention has been described above, the present invention is not limited to the above, and other various modifications can be made without departing from the spirit of the present invention. It is.

DESCRIPTION OF SYMBOLS 10 ... Brushless motor, 12 ... Motor shaft, 20 ... Stator, 21 ... Stator core, 22 ... Insulator, 23 ... Winding, 24 ... Teeth part, 25 ... Anti-vibration rubber, 30 ... Rotor, 31 ... Rotor housing, 32 ... Rotor Magnet, 33 ... peripheral wall part, 34 ... top wall part, 35 ... cylindrical part, 40 ... bearing holder, 41 ... holder part, 42 ... cylindrical part, 45 ... first bearing, 50 ... center piece, 51 ... plate part, 52 ... Shaft part, 53 ... Base part, 54 ... Housing part, 55 ... Second bearing, 60 ... Circuit board, 61 ... Heat sink, 70 ... Case, 80 ... Cover, 101 ... First joint part, 102 ... Second joint Part 103, first projection part (first clamping part), 104 ... second projection part (second clamping part), 105 ... first contact part, 106 ... second contact part, 107 ... in the circuit board End of the first contact portion, the portion between the second projection and the second contact portion in the 108 ... case, a portion between the second contact portion and the second joint portions in 109 ... Case

Claims (8)

An annular stator;
A center piece having a plate portion facing the stator in the axial direction of the stator;
A circuit board provided on the opposite side of the stator with respect to the plate portion;
A case for accommodating the circuit board with the plate portion;
A first joint formed on the outer edge of the plate portion;
A second joint formed on the outer edge of the case and joined to the first joint;
A first clamping part formed inside the outer edge part of the plate part;
A second clamping part formed inside the outer edge part of the case and clamping the circuit board with the first clamping part;
A first contact portion formed between the first joint portion and the first sandwiching portion in the plate portion and extending along an outer edge portion of the plate portion;
A second abutting portion formed between the second joint portion and the second clamping portion in the case, extending along an outer edge portion of the case, and abutting against the first abutting portion; ,
Brushless motor with The first clamping portion is a first protrusion extending from the plate portion toward the circuit board,
The second clamping part is a second protrusion extending from the case toward the circuit board.
The brushless motor according to claim 1. The portion between the second protrusion and the second contact portion in the case is elastically deformed toward the plate portion with the second protrusion as a fulcrum,
The portion between the second contact part and the second joint part in the case is elastically deformed toward the plate part side with the second contact part as a fulcrum.
The brushless motor according to claim 2. The second protrusion is located on the opposite side of the second protrusion with respect to the first protrusion.
The brushless motor according to claim 3. The first protrusion is located closer to the end of the circuit board than the second protrusion on the first contact portion side.
The brushless motor according to claim 4. The circuit board has a heat sink,
The first sandwiching portion and the second sandwiching portion sandwich the heat sink,
The brushless motor as described in any one of Claims 1-5. The plate portion of the center piece is opposed to the annular stator in the axial direction of the stator, a circuit board is provided on the opposite side of the stator with respect to the plate portion, and the circuit board is accommodated by the plate portion and the case A temporary assembly process,
While joining the 1st junction part formed in the outer edge part of the said plate part, and the 2nd junction part formed in the outer edge part of the said case, the 1st formed inside the outer edge part of the said plate part The circuit board is sandwiched between the sandwiching portion and the second sandwiching portion formed inside the outer edge portion of the case, and between the first joint portion and the first sandwiching portion in the plate portion A main assembly step of bringing the formed first contact portion into contact with the second contact portion formed between the second joint portion and the second clamping portion in the case;
Of manufacturing a brushless motor. In the temporary assembly step, in a state where the circuit board is sandwiched between the first sandwiching portion and the second sandwiching portion, a gap dimension G1 between the first joint portion and the second joint portion, and Gap dimension G2 between the first contact portion and the second contact portion satisfies G1 ≧ 0, G2 ≧ 0, G1 ≧ G2.
The manufacturing method of the brushless motor of Claim 7.

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