JPS62250853A - Structure of stator for brushless motor - Google Patents

Abstract

PURPOSE:To strive for a thinner-shaped stator of higher performance, by interfacing a stator yoke, a circuit substrate and a sheet-coil each formed into sheet, by positioning them and by securing them one another. CONSTITUTION:A brushless motor is composed of a rotor 2 and a stator 3. The rotor 2 is composed of a rotor yoke 4, an axis of rotation 5 and a magnet motor 6. A stator 3 is composed of a sheeted stator yoke 10, a circuit substrate 20 formed into almost the same shape as in this stator yoke 10, an almost annular and sheeted sheet-coil 30 to rotate the rotor 2 and a bearing unit 40.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a stator structure for a brushless motor.

[Summary of the Invention] This invention provides a stator structure for a brushless motor, such as a magnetic detection method that uses a Hall element (Hall LC, Mrt element) to detect the magnetic pole of a magnet rotor, in which the shaft of the rotor can be rotated through a bearing. By combining the stator yoke that supports the stator yoke, the circuit board on which the Hall elements and other electronic components are positioned and embedded, and the sheet coil that rotates the rotor in the form of sheets, the brushless motor can be made even more compact. Moreover, it is made flat and thin so that performance can be improved at low cost.

[Prior Art] For example, brushless motors are used as motors with extremely small rotational irregularities, such as cylinder motors of VTRs, spindle motors of floppy disk drives, and capstan motors of cassette decks, which are extremely sensitive to noise generation. This brushless motor eliminates the need for contact members such as brushes and commutators, and rotates a magnet instead of rotating a coil. On one side, various electronic components such as a coil that rotates the magnet rotor, a Hall element that detects the magnetic pole position of the magnet rotor, and a logic IC are soldered or glued directly or indirectly via a flexible printed circuit board, etc. It is constructed by protruding and fixing with etc.

[Problems to be Solved by the Invention] With the recent trend toward thinner V'rRs, cassette decks, etc., brushless motors are required to be smaller and thinner. Since a plurality of various electronic components such as ICs are scattered and protrude, it has been impossible to make the stator portion of the brushless motor sufficiently small and thin.

In addition, it is difficult to precisely position multiphase coils and various electronic components to the stator yoke, etc., and to fix them with soldering, etc., which causes problems such as variations in the performance of the assembled branless motor. Ta.

Therefore, the present invention provides a stator structure for a brushless motor that can be made small, flat, and thin at low cost, and exhibit high performance.

[Means for Solving the Problems] The stator structure of the brushless motor of the present invention has a stator yoke formed in a sheet shape and having a bearing that rotatably supports the shaft of the rotor, and one electronic component each embedded therein. A circuit board formed in a sheet shape and disposed on one side of the stator yoke, and a circuit board coaxially spaced between one side of the stator yoke and one side of the rotor with a predetermined clearance from one side of the rotor. and a sheet coil arranged to rotate the rotor.

[Effect] Each stator yoke is formed into a sheet.

By aligning the circuit board and the sheet coil and fixing them to each other, a thin and high-performance brushless motor stator is constructed.

[Example] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In FIG. 1, 1 is a brushless motor.

This brushless motor 1 is composed of a rotor 2 and a stator 3.

The rotor 2 includes a disc-shaped rotor yoke 4 and a rotating shaft 5 that protrudes perpendicularly from the center of the inner surface 4a of the rotor yoke 4.
and a disc-shaped annular magnet rotor 6 bonded to the inner surface 4a of the rotor yoke 4 with an adhesive or the like. This magnet rotor 6 has magnetic poles N and S arranged alternately. Further, as shown in FIG. 2, a frequency generator (FG) pattern 6a is printed on the reflective surface of the magnet rotor 6 relative to the inner surface 4a of the rotor yoke 4.

The stator 3 includes a stator yoke lθ formed in a sheet shape from a magnetic metal such as a silicon steel plate, a circuit board 20 formed in a sheet shape approximately the same as the stator yoke IO, and a circuit board 20 formed in a substantially annular and sheet shape. A bearing unit 40 is attached to the stator yoke IO with a screw (not shown) or the like and rotatably supports the rotating shaft 5 of the rotor 2. ing.

The stator yoke lO is formed into a substantially rectangular shape with a negative side being an arc. A large diameter hole 11 is bored near the arcuate side of the stator yoke lO, and a plurality of small diameter holes 12 are bored around this large diameter hole 11.

Then, by inserting the screw or the like into the small diameter hole 12 from one side (the top surface in the figure) of the stator yoke 10 and screwing it into the screw hole 41 formed in the bearing unit 40, the other side of the stator yoke IO (the top surface in the figure) Bearing unit 4 on the bottom surface)
It is designed to be fixed at 0. Also, stator yoke 1
On the side opposite to the arc side of 0, there is a pair of notches 13.1.
3 is formed.

"Circuit" (The board 20 is formed into three layers including a wiring board layer 21 and a protective layer 22 made of a thin resin film or the like that covers both sides of this wiring board layer 21.
Inside, there is a Hall element 23 as an electronic component at a predetermined position.
FG sensor 24. Logic IC 25, coil terminal coupling section 26. Each chip such as the connector-terminal coupling portion 27 is embedded and coupled. As a result, the circuit board 20 itself has functions such as a commutation circuit necessary for switching the current of the sheet coil 30 and creating a rotating magnetic field. The Hall element 23 is for detecting the position (magnetic pole) of the magnet rotor 6, and the FC sensor 24 is arranged to face the FC pattern 6a of the magnet rotor 6, and detects the rotation of the magnet rotor 6. This is to optically detect unevenness. Further, the stator yoke 10 of the circuit board 20
A hole 28 having a diameter larger than the diameter of the large diameter hole 11 and a pair of notches 29, 29 are formed at the portions corresponding to the large diameter hole 11 and the pair of notches 13, 13, respectively.

The sheet coil 30 has eight drive phases 31 formed by etching technology or the like, and is laminated in three layers. Two of these drive phases 31 are formed smaller than the other phases and cut out (1. IJ notch portion is indicated by reference numeral 32), and each drive phase 31 in the three layers is coaxially The phases are slightly shifted from each other. Also,
A coil terminal 33 is provided on the outer periphery of each layer of the sheet coil 30.
are protruding from each other.

These stator yoke 101, circuit board 20, and sheet coil 30 are mass-produced while maintaining high quality as a combined stator unit 3^ by the manufacturing method described below.

That is, as shown in FIG. 3, by means such as punching,
A stator yoke sheet 7 is manufactured in which a large number of stator yokes 10 are successively arranged at regular intervals.

Guide holes 7a are provided on both sides of the stator yoke sheet 7.
are drilled at equal intervals. Similarly, a circuit board sheet 8 and a sheet coil sheet 9 having a plurality of circuit boards 20 and sheet coils 30 consecutively spaced at the same interval so as to correspond to each stator yoke IO of the stator yoke sheet 7 are manufactured. do. Guide holes 8a and 9a are bored on both sides of the circuit board sheet 8 and on one side of the sheet coil sheet 9 at positions corresponding to the respective guide holes 7a of the stator yoke sheet 7.

Next, the circuit board sheet 8 is attached to the stator yoke sheet 7.
．． The sheet coil sheets 9 are stacked in order, and each of these sheets 7
．． 8.9 guide hole? A, 8a, 9a are inserted into the pilot bins 50 for alignment 1 positioning, and one side of each stator yoke 10 of the stator yoke sheet 7 (upper surface in the figure) is attached to the other side of each circuit board 20 of the circuit board sheet 8 ( (lower surface in the figure) and one side (upper surface in the figure) of each circuit board 20 of the circuit board sheet 8 and the other side (lower surface in the figure) of each sheet coil 30 of the sheet coil sheet 9 coaxially with each other. Fixed to. After the coil terminal coupling portion 26 of each circuit board 20 and the coil terminal 33 of each sheet coil 30 are soldered and fixed to form the stator unit 3A, each stator unit 3A is assembled by means such as a press. disconnect. The stator 3 of the brushless motor 1 is completed by screwing the bearing unit 40 to the thus obtained stator unit 3A shown in FIG. 4. At this time, I? of the circuit board 20? The G sensor 24 is exposed through the cutout 32 of the sheet coil 30.

The rotating shaft 5 of the rotor 2 is inserted and supported in the bearing unit 40 of the stator 3 configured as described above so that the F'G pattern 6a surface of the magnet rotor 6 and one side of the sheet coil 30 have a predetermined clearance. By doing so, the brushless motor I is completed. The stator yoke 01 circuit board 0 and the sheet coil 30, which constitute the main parts of the stator 3, can be integrated as a sheet-shaped stator unit 3A, so the stator 3 can be made flat and thin.

As a result, the parts constituting the brushless motor 1 can be simplified, automatic assembly of the brushless motor 1 can be facilitated, and the entire brushless motor 1 can be made smaller and thinner.

Further, the stator yoke 10. The circuit board 20 and sheet coil 30 are positioned and fixed with high precision.

Since the stator units 3A are cut, it is possible to continuously mass-produce stator units 3A that maintain a certain high quality, and productivity can be significantly improved. As a result, there is no variation in the performance of the assembled brushless motor 1, and a brushless motor 1 with high performance can be manufactured at low cost.

FIG. 5 shows a stator 3 according to another embodiment, in which a sheet coil 30 is fixed with adhesive to the large diameter hole 11 side of one side of the stator yoke 10 (upper surface in the figure) to increase the efficiency of the motor. That's what I did. Also, stator yoke I
A sheet coil 30 is placed on the side of the pair of notches 13 and 13 of O.
A circuit board 2OA having approximately the same thickness is fixed with an adhesive so that the sheet coil 30 and the circuit board 2OA do not overlap each other. In this circuit board 2OA, each chip such as a logic IC 25 as an electronic component is embedded, as in the circuit board 20 of the previous embodiment. Of course, as shown in FIG. 6, a circuit board 20B having a logic [C25] depth added thereto may be used.

In addition, instead of the rotor in which the magnetic rotor is provided with an FC pattern, another rotor in which an FG magnet is fixed to the outer peripheral surface of the rotor yoke is used, and the stator 3 of each of the above embodiments is used.
It may also be assembled into a brushless motor. In this case, a PG printed pattern or an MR sensor (6M1 resistance element) is provided on the circuit board to
Try to get G ratio output.

[Effects of the Invention] As described above, according to the present invention, the stator yoke that rotatably supports the shaft of the rotor via the bearing, the circuit board in which type F5 electronic components are embedded, and the sheet coil that rotates the rotor are each provided. By forming the stator into a sheet-like structure and combining them, the stator can be made smaller, flat, and thin.

As a result, the entire brushless motor has become even more compact.

It has the effect of being able to be made thinner and compatible with the thinner brushless motors that are required as VTRs, cassette decks, etc. have become thinner in recent years.

[Brief explanation of drawings]

1 to 4 show embodiments of the present invention, in which FIG. 1 is an exploded perspective view of a brushless motor, FIG. 2 is a perspective view of an inverted magnet rotor, and FIG. 3 is a stator manufacturing process. FIG. 4 is a perspective view of the stator,
FIGS. 5 and 6 are exploded perspective views of stators of other embodiments. l...Brushless motor, 2...Rotor, 3...
Stator, 5...Rotating shaft (shaft), 10...Stator yoke, 20°2OA, 20B...Circuit board, 23.
...Hall element (electronic component), 24...FG sensor (IX component), 25-I C (m component), 26...
- Coil terminal coupling part (? [m child part), 27... Connector one terminal coupling part (m child part), 3o... Sheet coil, 40... Bearing unit (bearing). Figure 6

Claims (1)

[Claims] A stator yoke formed in a sheet shape and having a bearing that rotatably supports the shaft of a rotor; and a stator yoke formed in a sheet shape with various electronic components embedded therein;
A circuit board disposed on one side of the stator yoke and a circuit board disposed coaxially between one side of the stator yoke and one side of the rotor at a predetermined clearance from one side of the rotor, A stator structure for a brushless motor characterized by comprising a rotating sheet coil.