JP2008005588A - Brushless motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a brushless motor which can improve its workability by facilitating and securing the solder treatment of a coil terminal and also is possible of thinning and downsizing. <P>SOLUTION: A substrate 11 has a one-sided pattern wiring face 11a, and also the pattern wiring face 11a is stuck onto a base plate 10, between a stator core 8 and the base plate 10, and this pattern wiring face 11a is provided with a coil round 20 to solder the coil terminal, and also is provided with a through hole 21 to pass the coil terminal 9a, and further the base plate 10 is provided with an open hole 22 in the section corresponding to the coil round 20 and the through hole 21, therefore the user can perform the work of soldering the coil terminal 9a to the coil round 20, making use of wide space from under the base plate. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a small brushless motor used for household appliances and the like.

  A small brushless motor used in a conventional household appliance is shown in FIG. 9 (see, for example, Patent Document 1). FIG. 9 shows a stator base 70 made of a thin stainless steel plate and a circuit board 71 made of a glass cloth epoxy plate on the upper surface, and three supporting frame pieces 70b standing up with a bridge portion in the center. A shaft holder 73 is provided in which the part of the support frame piece 70b is integrally molded with resin.

  On the outer periphery of the shaft holder 73, a stator core 74a around which armature coils 74b are wound is fixed to a plurality of salient poles by means such as adhesion and welding, and terminals 74c of each armature coil are connected to predetermined ends of the circuit board 71. Soldered to the pattern. On the other hand, the rotor R includes a shaft 75 that is directly rotatably mounted on the shaft holder 73, a rotor case 76 that is attached by press-fitting the shaft 75, and a salient pole of the stator core 74a inside the rotor case 76. A magnet 77 is provided via a radial gap.

  On the circuit board 71, a wiring pattern for each phase (U phase, V phase, W phase) of the coil is made, and the terminal 74c of the coil is soldered to the round 71a for each phase. The stator core 74a is positioned immediately above the round 71a, and the rotor R rotates on the outer periphery of the salient pole of the stator core 74a.

Therefore, the terminal 74c of the coil is provided with a soldering round 71a at a portion extending from the inner side of the stator core 74a to the outer side of the wiring pattern. A hall element (not shown) for detecting the rotation of the rotor R is mounted on the substrate in the vicinity of the driving magnet.
JP 2000-90527 A

  However, in such a conventional structure, in order to solder a board | substrate and the terminal of a coil, it had to be soldered by the narrow clearance gap. In addition, since soldering is performed in a narrow gap, considerable care and skill are required for reliable soldering. For this reason, there are cases where the quality is deteriorated due to an insulation failure due to agglomerates generated due to poor workability or a contact failure due to void formation inside the solder.

  This type of brushless motor is also required to be thin. For this reason, it is conceivable to reduce the number of stator cores, but this leads to a reduction in motor torque. To solve this problem, if the number of coils wound around the stator core is increased, the coil thickness increases and the motor cannot be thinned.

  In addition, this type of brushless motor is required to be downsized. If the Hall element is inside the driving magnet in the radial direction, the mounting space for the stator core, the coil, the magnet, or the like may be reduced. Therefore, the torque characteristic required for the motor may be lowered. However, when the Hall element is placed on the outer periphery of the magnet, the outer shape of the motor becomes large.

  The present invention has been made to solve the above-described problems, and can easily and surely solder the coil terminal to improve workability, and can be reduced in thickness and size. An object is to provide a motor.

In order to achieve the above object, a brushless motor of the present invention includes a rotating shaft, a rotor case that rotates integrally with the rotating shaft, a rotor that is disposed in the rotor case, and the rotating shaft. A bearing that rotates the bearing, a stator housing that fixes the bearing, a stator core that is fixed around the bearing housing and has a salient pole facing the inner periphery of the rotor magnet, and a coil wound around the stator core, A stator having a base plate made of a plate-like conductor fixed to the bearing housing and a substrate provided on the base plate is provided between the stator core and the base plate, and the pattern wiring of the substrate The surface is pasted against the base plate surface,
The pattern wiring surface is provided with a coil round for fixing the coil terminal and a through hole through which the coil terminal is passed, and the base plate is provided with an opening hole corresponding to the coil round and the through hole. The coil terminal penetrates the through hole and is fixed to the coil round by soldering.

The brushless motor of the present invention is characterized in that a storage hole for avoiding interference with the coil is provided in the base plate facing the coil wound around the stator core.
Further, the brushless motor of the present invention is characterized in that the base plate facing the coil wound around the stator core is provided with a partially thinned recess to avoid interference with the coil.
In the brushless motor of the present invention, a hall element for detecting the magnetic force of the rotor magnet is disposed on the pattern surface of the substrate, and the hall plate is opposed to the hall plate. A hall element through hole for avoiding interference with the element is provided.

According to the brushless motor of the present invention, the pattern wiring surface side of the substrate is attached to the base plate, and the substrate is provided with the coil round for soldering the coil terminal to the pattern wiring surface. Since there are through-holes through which coil terminals pass and the base plate has opening holes corresponding to the coil rounds, the soldering work between the coil terminals and the coil rounds is wide from the bottom side of the base plate. This can be done using space. Therefore, the soldering operation can be performed easily and reliably.
Further, since the visual confirmation of the solder state after soldering can be easily performed, the reliability can be improved.
Furthermore, since it can design without considering the solder height after soldering between a stator core and a coil terminal, and a coil round, the height of a stator core can be made low and a motor can be reduced in thickness.

If the base plate facing the coil wound around the stator core is provided with a storage hole that avoids interference with the coil, in addition to the above effect, the height of the lower portion of the coil is equivalent to the height of the stator core. Since the height can be reduced, the motor can be further reduced in thickness.
If the base plate facing the coil wound around the stator core is provided with a partially thinned recess to avoid interference with the coil, in addition to the above effects, the lower height of the coil Since the height of the stator core can be reduced by this amount, the motor can be further reduced in thickness.

  In addition, a Hall element that detects the magnetic force of the rotor magnet is disposed on the pattern wiring surface of the substrate, and a Hall element through hole is provided in the base plate that faces the Hall element in order to avoid interference with the Hall element. In addition to the above effects, the height of the stator core can be lowered by the height of the Hall element, so that the motor can be made thinner.

  Hereinafter, the present invention will be described in detail with reference to the best mode for carrying out the present invention shown in the drawings.

(First embodiment)
FIG. 1 is a cross-sectional view showing a state of the brushless motor according to the first embodiment of the present invention, and shows a cross-section in the direction of arrows AA in FIG. 2 shows a stator before incorporating the rotor of the brushless motor of FIG. 1, wherein (a) is a plan view and (b) is a side view. 3 shows the stator before incorporating the rotor of the brushless motor of FIG. 1, (a) is a bottom view of the stator, (b) is an enlarged view of a B portion in (a), and the coil terminal is in a state before soldering. It is. FIG. 4 is a partial modification of the portion B in FIG.

  1 to 4, the brushless motor includes a rotor 1 and a stator 2.

  The rotor 1 includes a rotating shaft 3, a rotor case 4 that rotates integrally with the rotating shaft 3, and a rotor magnet 5 disposed in the rotor case 4. The rotor magnet 5 is multipolarized as many poles as necessary.

  On the other hand, the stator 2 includes a bearing 6 that rotatably supports the rotating shaft 3, a bearing housing 7 that fixes the bearing 6, and a salient pole that is fixed around the bearing housing 7 and faces the inner periphery of the rotor magnet 5. A stator core 8 having 8a, a plurality of arm portions 8b provided radially, and a coil 9 wound around the arm portion 8b and connected in three phases, and a plate shape for fixing the bearing housing 7 And a substrate 11 having a pattern wiring provided on the base plate 10 for transmitting a drive signal.

  This coil 9 is a three-phase star connection and has a U phase, a V phase, and a W phase. The rotor magnet 5 is configured so that the rotor 1 rotates in a certain direction by the interaction of attraction and repulsion by the rotating magnetic field generated by the three-phase current flowing through the coil 9.

  The substrate 11 of the brushless motor configured as described above is located between the stator core 8 and the base plate 10, and the pattern wiring surface 11 a of the substrate 11 faces the base plate 10 and is fixed by adhesion or double-sided tape. The substrate 11 is a flexible substrate having a pattern wiring 11a only on one side. This flexible substrate has only one layer of copper foil on one side of a polyimide film, and a cover film is attached as an insulating layer to the copper foil wired in a desired pattern. The substrate 11 may be a glass epoxy substrate or a paper phenol resin substrate using a non-flexible material.

  As this flexible substrate, a very thin substrate having a thickness of about 0.2 mm is used. Therefore, compared with the case where a glass epoxy substrate or a paper phenol resin substrate is used, the thickness is reduced and the motor can be made thinner.

  The connection terminal 11b of the substrate 11 inputs and outputs driving signals, and is provided on the base plate 10 side instead of the conventional stator core 8 side. However, even if the wiring surface of the connection terminal 11b is reversed, the female terminal on the connection side of the drive signal can be used as before because it is detachable.

  A coil round 20 for soldering the coil terminal 9 a is provided on the pattern wiring surface 11 a of the substrate 11. The coil round 20 is provided between each of the salient poles 8a extending from the inner side of the stator core 8 to the outer side of the substrate 11 and slightly outside. The coil round 20 is provided with three locations 20a, 20b, and 20c for soldering the three-phase connection coil terminals 9a wound around the stator core 8. The coil round 20 may be on the inner side of the arm portion 8b of the stator core 8.

  In the vicinity of the center of the coil round 20, a through hole 21 through which the coil terminal 9a wound around the stator core 8 passes is provided. The through hole 21 is smaller than the outer diameter of the coil round 20 and larger than the diameter of the coil. And the coil round 20 has a solder part area required when soldering the coil terminal 9a.

The base plate 10 is provided with opening holes 22 at portions corresponding to the coil rounds 20 and the through holes 21. The opening hole 22 is larger than the outer diameter of the coil round 20. As a result, the coil terminal 9 a can be passed through the through hole 21 and the soldering operation between the coil terminal 9 a and the coil round 20 can be performed from the lower surface of the base plate 10. The coil terminal 9a is fixed to the coil round 20 with the solder connection portion 23a. Note that at least three or more opening holes 22 are provided.
Further, as shown in FIGS. 4A and 4B, the coil round 20 provided on the pattern wiring surface 11a of the substrate 11 may be provided separately from the through hole 21, or the coil round 20 may provide the through hole 21. You may provide so that a part may be enclosed.

  In the arrangement of the coil round 20 shown in the upper diagram, a U-phase terminal is soldered to 20a, a V-phase terminal is soldered to 20b, and a W-phase terminal is soldered to 20c. And the coil terminal 9a and the coil terminal of the other end are connected by the connection part 23b between another arm part 8b. The coil terminal at the other end is provided with a coil round (not shown) on the substrate 11, a through hole is provided near the center of the coil round, and the base plate corresponds to the coil round. An opening hole may be provided, and the coil terminal at the other end may be soldered to the coil round.

  Therefore, since the soldering between the coil terminal 9a and the coil round 20 can be performed in a space wider than the lower surface of the base plate 10 without soldering in the gap between the salient poles 8a of the stator core 8, the soldering operation can be performed easily and reliably. It can be performed.

  Further, since the soldering work can be performed from the lower surface of the base plate 10, the workability during soldering can be remarkably improved and the visual confirmation of the solder state after soldering can be easily performed, so that the reliability can be improved.

  Further, since the soldering operation can be performed from the lower surface of the base plate 10, the tip of the soldering iron can easily reach the coil round 20, so that the manufacturing process can be shortened.

(Second Embodiment)
FIG. 5 is a cross-sectional view showing a state of the brushless motor according to the second embodiment of the present invention, and shows a cross-sectional view in the direction of arrow CC in FIG. 6A and 6B show a stator before the rotor of the brushless motor shown in FIG. 5 is assembled. FIG. 6A is a plan view and FIG. 6B is a side view. FIG. 7 shows the stator before incorporating the rotor of the brushless motor of FIG. 5, (a) is a bottom view of the stator, and (b) is an enlarged view of a portion D in (a). FIG. 8 shows a partial modification of FIG.

  In these drawings, the same components as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

In the present embodiment, the first difference from the first embodiment is that the lower portions 9b of the coils 9 wound around the radial arm portions 8b provided on the stator core 8 are provided on the base plate 10 and the substrate 11, respectively. This is a point stored in the storage unit 31. This is because an accommodation hole 31 a is provided in the base plate 10 facing the lower portion 9 b of the coil 9 wound around the stator core 8 in order to avoid interference with the coil 9. The base plate 10 and the substrate 11 have substantially the same opening size.
According to such a configuration, the same effects as those of the first embodiment can be obtained, and the height of the stator core 8 can be reduced by the height of the lower portion 9b of the coil 9, so that the motor can be thinned.
Further, as shown in FIG. 8, in order to avoid interference with the lower portion 9 b of the coil 9 on the surface of the base plate 10 facing the coil 9 wound around the stator core 8 by opening only the substrate 11. In addition, the same effect can be obtained by providing the recess 32 that is partially thinned by drawing.

In the present embodiment, a second point different from the first embodiment is that a Hall element 41 for detecting the magnetic force of the rotor magnet 5 is disposed on the pattern wiring surface 11 a of the substrate 11. The base plate 10 that is opposed to is provided with a hall element through hole 42 for avoiding interference with the hall element 41. According to such a configuration, the height of the rotor 1 can be reduced by the height of the Hall element 41, and the motor can be further reduced in thickness.
The Hall element 41 for detecting the rotation of the rotor magnet 5 is attached to the Hall element round 44 provided on the same plane as the coil round 20 in a state where the Hall element 41 is inserted into the Hall element through hole 42 provided in the base plate 10. Furthermore, a shielding part 43 made of a part of the base plate 10 may be provided between the storage part 31 and the hall element through hole 42.
Even with such a configuration, the height of the rotor 1 can be reduced by the height of the Hall element 41, the motor can be further reduced in thickness, current flows through the coil 9, and leakage magnetic flux from the coil 9 is generated. Even if it exists, since the shield part 43 of the conductor is provided, the Hall element 41 is not affected by the leakage magnetic flux, so that a normal drive waveform can be obtained from the Hall element 41.
Therefore, it is possible to prevent the Hall element 41 from outputting an incorrect signal and consequently abnormal rotation as a motor.

  It should be noted that the present invention is not limited to the above-described embodiments, and can be appropriately modified and implemented without departing from the spirit of the present invention.

It is sectional drawing which shows the state of the brushless motor concerning the 1st Embodiment of this invention, and has shown the cross section of the arrow AA direction of Fig.2 (a). The stator before incorporating the rotor of the brushless motor of FIG. 1 is shown, (a) is a plan view and (b) is a side view. The stator before incorporating the rotor of the brushless motor of FIG. 1 is shown, (a) is a bottom view, (b) is an enlarged view of a portion B in (a), and shows a state before soldering of coil terminals. It is a partial modification concerning 1st Embodiment. It is sectional drawing which shows the state of the brushless motor concerning the 2nd Embodiment of this invention, and has shown the cross section of the arrow CC direction of Fig.6 (a). The stator before incorporating the rotor of the brushless motor of FIG. 5 is shown, (a) is a plan view, and (b) is a side view. The stator before incorporating the rotor of the brushless motor of FIG. 5 is shown, (a) is a bottom view, and (b) is an enlarged view of a portion D in (a). It is a partial modification concerning 2nd Embodiment. It is sectional drawing of the conventional brushless motor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotor 2 Stator 3 Rotating shaft 4 Rotor case 5 Rotor magnet 6 Bearing 7 Bearing housing 8 Stator core 8a Salient pole 8b Arm part 9 Coil 9a Coil terminal 9b Lower part 10 Base plate 11 Board | substrate 11a Pattern wiring surface 11b Connection terminal 20 Coil round 21 Through hole 22 Opening hole 23a Solder connection part 23b Connection part 31 Storage part 31a Storage hole 32 Recessed part 41 Hall element 41a Hall element terminal 42 Hall element through hole 43 Shielding part 44 Hall element round

Claims (4)

A rotor having a rotation shaft, a rotor case that rotates integrally with the rotation shaft, and a rotor magnet disposed in the rotor case;
A bearing for rotating and supporting the rotating shaft, a bearing housing for fixing the bearing, a stator core having a salient pole fixed around the bearing housing and facing the inner periphery of the rotor magnet, and wound around the stator core A stator having a coil, a base plate of a plate-like conductor fixed to the bearing housing, and a substrate provided on the base plate;
The substrate is between the stator core and the base plate, and a pattern wiring surface of the substrate is attached to face the base plate surface,
The pattern wiring surface is provided with a coil round for fixing the coil terminal and a through hole for passing the coil terminal,
The base plate is provided with an opening hole in a portion corresponding to the coil round and the through hole,
The coil terminal passes through the through hole and is soldered to the coil round;
A brushless motor characterized by that. The brushless motor according to claim 1,
A brushless motor, wherein the base plate facing the coil wound around the stator core is provided with a storage hole for avoiding interference with the coil. The brushless motor according to claim 1,
The brushless motor according to claim 1, wherein the base plate facing the coil wound around the stator core is provided with a partially thinned recess to avoid interference with the coil. The brushless motor according to claim 1,
A Hall element that detects the magnetic force of the rotor magnet is disposed on the pattern wiring surface of the substrate,
A brushless motor, wherein the base plate facing the hall element is provided with a hall element through hole that prevents interference with the hall element.

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