JPS62236351A - Flat brushless motor and manufacture thereof - Google Patents

Abstract

PURPOSE:To enhance the efficiency of a flat brushless motor by composing the peripheral edge of a stator yoke of the laminate of a flat planar magnetic path material and an insulating layer and arranging a driving winding on the layer to reduce a gap between the magnetic path material of a rotor magnet and a stator yoke. CONSTITUTION:The peripheral edge of a central hole formed at a stator yoke is formed as a laminate by bonding a sheetlike insulating base material 7 by an adhesive 8 to a magnetic path material 8. Simultaneously, a metal foil such as copper foil is bonded on an insulating layer 12 made of a sheetlike insulating material 6 and the material 7. This foil is etched to form a printed pattern layer 11 for wiring for a driving winding and a rotor position detector on the layer 12.

Description

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, a drive winding is disposed on a stator yoke, a rotor magnet is disposed opposite to the drive winding through a predetermined gap, and supports the rotating shaft. The present invention relates to a flat brushless motor in which a bearing is disposed in a central opening formed in the stator yoke and a method for manufacturing the same, and in particular to an improved stator yoke.

In a conventional flat brushless motor, for example, as shown in FIG. 1, a drive winding 2 is provided on a stator yoke 1, and a rotor magnet 3.3' is rotated. The magnetic flux emitted from the rotor magnet 3 is once guided to the stator yoke 1, and then to the opposite rotor magnet 3'.
Return to Therefore, the smaller the distance l of the gap between the rotor magnet 3.3' and the stator yoke 1, the smaller the magnetic reluctance of the above-mentioned magnetic path. The magnetic flux density at the magnet 3.3' becomes higher, and the utilization efficiency of the magnet 3.3' improves.

The distance l of the gap is l=1. +β2+l.

It can be expressed as Here, 11 (shown in an exaggerated manner) is a drive winding 2 and a rotor magnet 3 .
3' is the clearance to prevent contact during rotation, 12 is the thickness dimension of the drive winding 2 with the required number of turns,
13 is the thickness of an insulating layer for insulating the drive winding 2 from the stator yoke 1 (usually made of a high permeability material such as an iron plate or a silicon steel plate). Note that the thickness of this insulating layer may be approximately 0.1 mm in terms of safety standards, but in the case of conventional flat brushless motors, as shown in Figure 2, for example, the thickness of this insulating layer is molded with insulating material. A flange 5 is provided on the winding bobbin 4, and this flange 5 is used as an insulating layer. However, in this case, the thickness l of this insulating layer is usually about 0.5 mm, considering the moldability of the bobbin, etc.
Even if it were to be thinned, it could only be made as thin as 0°3.

On the other hand, the relationship between the gap distance l and the magnetic flux leakage coefficient in the flat type brushless motor shown in FIG. 1 is as shown in FIG. 3, according to actual measurements made by the present inventor. That is,
As the gap becomes larger, leakage of magnetic flux increases rapidly, and the magnetic flux acting on the coil decreases. Therefore, the first
If the thickness of the insulating layer is about 0.51 mm as in the conventional motor shown in FIGS.

The present invention was invented in order to correct the above-mentioned drawbacks, and the brushless motor according to the present invention is the flat brushless motor described at the beginning, in which the stator yoke is (a) flat-shaped. a magnetic path material; (b) a one-color edge layer made of an insulating base material and an adhesive to ensure thickness and adhered to the flat magnetic path material; (c) the flat magnetic path material; the insulating layer deposited on the stator yoke, and a printed pattern layer for wiring formed directly on the insulating layer without using any other base material, and the peripheral edge of the center opening formed in the stator yoke is formed in the flat plate shape. consisting of a laminate of a magnetic path material and the insulating layer, and in order to arrange the bearing in the central opening,
The peripheral portion made of a laminate of the flat magnetic path material and the insulating layer is directly coupled to the bearing, and the drive winding is disposed on the insulating layer.

In addition, the method for manufacturing a brushless motor according to the present invention includes: (a) adhesion to an insulating base material to ensure thickness in the method for manufacturing a flat brushless motor described at the beginning;
Okay 1. □2, □□Ekayo, gaa□6o-o.

and (b) bonding a metal foil onto the insulating layer.
Then, by etching the metal foil and directly forming a printed pattern layer for wiring on the insulating layer adhered to the flat magnetic path material without intervening another base material, the flat magnetic path material is etched. (c) obtaining the stator yoke comprising a shaped magnetic path material, the insulating layer, and the wiring printed pattern layer; (d), before and after the steps (b) and (c), the center opening having a peripheral edge made of a laminate of the flat magnetic path material and the insulating layer; forming a stator yoke; (e) after the step (d), laminating the flat magnetic path material and the insulating layer in order to arrange the bearing in the center opening of the stator yoke; and a step of directly coupling the peripheral portion of the body to the bearing.

Next, embodiments of the present invention will be described with reference to FIGS. 4 to 6.

First, a first embodiment of the present invention will be explained with reference to FIGS. 4 and 6. The flat brushless motor of this first embodiment is the motor shown in FIG. 1 with an improved stator yoke. The motor has substantially the same structure as the motor shown in FIG. 1, except that the winding bobbin 4 is omitted and the structure of the stator yoke and the size of the gap distance l are different. Therefore, the first embodiment will be described below with reference to FIG. 1 as well.

In FIG. 4, reference numeral 6 denotes a sheet-like insulating base material made of a polyester sheet or the like to ensure thickness, and an adhesive material 7 such as polyamide is applied to the bottom surface of this insulating base material 6 to form a silicon steel plate or the like. It is adhered to the magnetic path material 8 consisting of. A laminate consisting of these members 6, 7, and 8 is then formed.

At the same time, a metal foil such as copper foil is bonded onto the insulating layer 12 made up of the sheet insulation base material 6 and the adhesive 7. and,
By etching this metal foil, the insulating layer 1
Drive winding 2 and rotor position detection element (not shown) on 2
A printed pattern layer 11 for wiring is formed.

Further, before and after the step of forming the wiring printed pattern layer 11, the laminate is formed into the shape shown in FIG. 6, and an opening 13 is formed in the center thereof.

Through the above steps, a laminate of the magnetic path material 8, the adhesive N7, and the sheet-like insulating base material 6 is formed, and the wiring printed pattern layer 11 is formed on the sheet-like insulating base material 6 without intervening other base materials. A directly formed stator yoke 1 shown in FIG. 6 can be obtained.

Next, as shown in FIG. 1, the annular peripheral edge 1a of the center opening 13 of the stator yoke 1 is fitted and fixed into the annular fitting groove 15 of the radial bearing 14, thereby fitting the peripheral edge 1a into the co-rotating wheel 16. It is directly connected to the radial bearing 14 that supports the. In this case, an insulating layer 12 is laminated on a magnetic path material 8 at the peripheral edge 1a of the stator yoke 1, and this insulating layer 12 is made of a sheet-like insulating base material 6 such as a polyester sheet and an adhesive material 7. It has moderate elasticity. Therefore, the stator yoke 1 is connected to the radial bearing 14.
It is extremely easy to bond tightly and firmly to the

According to the flat brushless motor of this first embodiment,
The insulation N12 provided on the stator yoke l is composed of a sheet-like insulation base material 6 and an adhesive material 7 to ensure the thickness,
Further, the sheet-like insulating base material 6 is adhered to the flat magnetic path material 8 by the adhesive 7, and the wiring printed pattern Fill is attached to the flat magnetic path material 8. Since it is formed directly without using a base material, -
The drive winding 2 can be directly disposed on the insulating layer 12. Therefore, the winding bobbin 4 can be omitted compared to the case where a stator yoke consisting of only a magnetic path material such as an iron plate is used, as in the case of the conventional flat brushless motor shown in FIGS. 1 and 2. Therefore, the gear gap between the rotary magnet 3.3' and the magnet 3.3' of the stator yoke 1 can be reduced and the utilization efficiency of the magnet 3.3' can be increased. The manufacturing cost can be reduced, and the entire motor can be made small and simple.

In addition, the stator yoke I not only has high mechanical strength, but also good heat resistance, dimensional stability, and machinability, and has a magnetic shielding effect, and the material thereof is inexpensive, making it suitable for mass production.

Further, since the flat magnetic path material 8, the insulating layer 12, and the printed wiring pattern N11 are integrated, the number of parts can be reduced and the motor can be easily assembled.

Further, the printed pattern layer 11 for wiring is directly formed on the insulating layer 12 adhered to the flat magnetic path material 8 without using any other base material, and the drive winding 2 is arranged on this insulating layer 12. Since the terminals of the drive winding 12 do not need to be drawn out of the stator yoke, they can be shortened (as in the case where the terminals are long), and the contact of the terminals to the rotor and the motor It is possible to effectively prevent wire breakage due to vibration during driving.

Furthermore, since the metal foil is etched after forming a laminate consisting of the magnetic path material 8, the adhesive layer 7, the sheet-like insulating base material 6, and the metal foil, the laminate is rolled before the etching. Therefore, the thickness of the insulation Jii 12 can be kept almost constant at all times, and it is also possible to effectively prevent bubbles from floating on the sheet-shaped insulation base material 6 and the metal foil with respect to the magnetic path material 8. be able to.

Further, in the above etching, since the magnetic path material 8 can be used as a reference position, the wiring printed pattern Fi can be etched with respect to the center opening 13 of the stator yoke 1.
ll can be positioned very precisely. Therefore, the rotary shaft 16 is disposed at a predetermined position with respect to the center opening 13 via the radial bearing 14, and the drive winding is disposed at a predetermined position with respect to the wiring printed pattern layer 11. The relative positional relationship with the wire 2 can always be accurately regulated, and as a result, a motor with less torque unevenness can be provided.

Further, the stator yoke 1 has a bearing 1 at its peripheral edge 1a.
4, and since the peripheral edge portion 1a is formed by laminating the flat magnetic path material 8 and the insulating layer 12, even if the magnetic path material 8 is relatively thin and has low strength, The stator yoke 1 can be firmly coupled to the bearing 14.

Next, a second embodiment of the present invention will be explained with reference to FIGS. 5 and 6. The flat brushless motor of this second embodiment is similar to the first embodiment shown in FIGS. 4 and 6. This is a motor with a further improved insulation layer.
This motor has substantially the same structure as the motor of the first embodiment, except that the structure of i12 is different. Therefore, in the following, as in the case of the first embodiment, the second embodiment will be explained with reference to FIG.

In FIG. 5, reference numeral 9 denotes a cross-shaped insulating base material made of glass fiber or the like to ensure thickness. After impregnating the cross-shaped insulating base material 9 with an adhesive 10 such as epoxy, the adhesive The cross-shaped insulating base material 9 is adhered to the flat magnetic path material 8 made of a silicon copper plate or the like using the material 10. Therefore, the adhesive material 10 is three-dimensionally intertwined with the cross-shaped insulating base material 9 to form a laminate consisting of the insulating layer 12 and the magnetic path material 8 that exist as a three-dimensional porous structure in the insulating base material 9. be done.

At the same time, a metal foil such as copper foil is bonded onto the insulating layer 12 consisting of the cross-shaped insulating base material 9 and the adhesive 10. By etching this metal foil, the insulating layer 1 is etched.
Drive winding 2 and rotor position detection element (not shown) on 2
A printed pattern layer 11 for wiring is formed.

Next, in the same manner as in the first embodiment described above, the sixth
After obtaining the stator yoke 1 shown in the figure and placing the drive winding 2 directly on the insulating layer 12 of the stator yoke 1, the stator yoke 1 is directly coupled to the radial bearing 14 as shown in FIG. .

According to the flat brushless motor in this second embodiment, the first actual diameter shown in FIGS. 4 and 6 is 1.1.72. Tsu, :l'e 5'lJ'*Oh, 8
□Oh. Not only does it provide the same numerous effects, but it also provides excellent effects as described below.

That is, according to the second embodiment, the cross insulation base material 9
was impregnated with an adhesive 10, and then the cross-shaped insulating base material 9 was adhered to the flat magnetic path material 8 using the adhesive 10. Therefore, unlike the case of the first embodiment shown in FIG. 4, it is not affected by uneven application of the adhesive material to the insulating base material, so that thin film insulation with a stable thickness of about 0.1 mm can be achieved. Layer 12 can be easily obtained. Therefore, by reducing the gap between the rotor magnet 3.3' and the magnetic path material 8 of the stator yoke 1, the magnetic flux leakage coefficient can be set to a much smaller value than in the conventional case (approximately 1 in Fig. 3). (approximately L2 in FIG. 3) can be achieved very easily.

Further, since the cross-shaped insulating base material 9 is impregnated with the adhesive 10 and then the insulating base material 9 is bonded to the magnetic path material 8, the adhesive 10 is attached to the cross-shaped insulating base material 9 three-dimensionally. They are intertwined and exist in this insulating base material 9 as a three-dimensional porous structure.

Therefore, when applying the adhesive 7 to the lower surface of the sheet-like insulating base material 6 and bonding the insulating base material 6 to the magnetic path material 8 as in the case of the first embodiment shown in FIG. In comparison, the adhesive strength of the cross-shaped insulating base material 9 to the magnetic path material 8 can be further increased. Therefore, there is no fear that the cross-shaped insulating base material 9 will peel off from the magnetic path material 8, even if an expensive adhesive with particularly high adhesive strength is not used.

Note 1. In the first and second embodiments described above, if the silicon steel plate used as the magnetic path material is divided and a plurality of sheets are laminated with adhesive, the eddy current loss will be reduced and the mechanical This is extremely effective as it also eliminates noise.

Since the present invention has the above-described configuration, it is possible to reduce the gap between the rotor magnet and the magnetic path material of the stator yoke, thereby increasing the utilization efficiency of the magnet. Furthermore, the manufacturing cost can be reduced, and the entire motor can be made smaller and have a simpler configuration.

In addition, the stator yoke not only has high mechanical strength, but also good heat resistance, dimensional stability, and machinability, and has a magnetic shielding effect.The material used for the stator yoke is inexpensive, and it is suitable for mass production.

Furthermore, since the flat magnetic path material, the insulating layer, and the wiring printed pattern layer are integrated, the number of parts can be reduced and the motor can be easily assembled.

In addition, since each terminal of the drive winding does not have to be pulled out of the stator yoke, it can be shortened, and therefore, unlike when the terminals are long, contact of the terminals with the rotor and disconnection due to vibration when driving the motor can occur. etc. can be effectively prevented.

Furthermore, since it is possible to roll the laminate consisting of the magnetic path material, insulating layer, and metal foil prior to etching the metal foil to form the printed pattern layer for wiring, the thickness of the insulating layer can always be kept almost constant. It is also possible to effectively prevent bubbles from floating on the sheet-like insulating base material and metal foil with respect to the magnetic path material.

Furthermore, when etching to form a printed pattern layer for wiring, it is possible to perform etching using the magnetic path material as a reference position, so the relative positional relationship between the motor's rotating shaft and drive windings can always be accurately determined. can be regulated,
Therefore, a motor with less torque unevenness can be provided.

In addition, the stator yoke is directly connected to the bearing at its peripheral edge, and since the peripheral edge is formed by laminating a flat magnetic path material and an insulating layer, the magnetic path material is relatively thin and has low strength. The stator yoke can also be strongly coupled to the bearing.

[Brief explanation of drawings]

Figure 1 is a schematic cross-sectional view of a conventional flat brushless motor.
Fig. 2 is an enlarged view of a portion of the motor shown in Fig. 1, Fig. 3 is a curve diagram showing the relationship between the gap distance between the rotor magnet and the stator yoke and the magnetic flux leakage coefficient in a flat brushless motor; FIG. 4 is a cross-sectional view of a part of a laminate of a magnetic path material and an insulating layer in the first embodiment of the present invention,
FIG. 5 1' is a perspective view of a part of a laminate of a magnetic path material and an insulating layer in a second embodiment of the present invention, and FIG. 6 is a perspective view of a part of the laminate shown in FIGS. FIG. 3 is a plan view of a stator yoke in the first and second embodiments. In addition, in the symbols used in the drawings, ■−・・−・−・−−−−−−・−・−・Stator yoke 2−−−−−−−−−−−−・−−−m−drive Winding wire 3.3' --- Rotor magnet 6 ---
...---...- Sheet-like insulating base material 7.10
−・−・Adhesive material 8−−−−−1−−・−1−−−−・−Magnetic path material 9−
・−・−−−−−−−−1−−−Cross-shaped insulating base material 12 ・−・−・−−−−−・−・− Horse mackerel color edge layer 13 ・・
・−・・−・−Center hole 14−−−−−・・−・・−・Radial bearing 16−・
・－・－・・－It is the axis of rotation.

Claims (1)

[Claims] 1. A drive winding is disposed on the stator yoke, a rotor magnet coupled to a rotating shaft is disposed opposite to the drive winding through a predetermined gap, and the rotor magnet is connected to the rotating shaft. In a flat brushless motor in which a bearing supporting the stator yoke is disposed in a central hole formed in the stator yoke, the stator yoke includes (a) a flat magnetic path material; and (b) ensuring thickness. (c) an insulating layer made of an insulating base material and an adhesive and adhered to the flat magnetic path material; (c) another base material is placed on the insulating layer adhered to the flat magnetic path material; a printed pattern layer for wiring formed directly without intervening, a peripheral edge of the center opening formed in the stator yoke is made of a laminate of the flat magnetic path material and the insulating layer, and the center In order to arrange the bearing in the opening, the peripheral portion made of a laminate of the flat magnetic path material and the insulating layer is directly connected to the bearing, and the driving winding is placed on the insulating layer. A flat brushless motor characterized by being provided with. 2. The flat brushless motor according to claim 1, wherein the insulating layer is made of a cross-shaped insulating base material impregnated with an epoxy adhesive. 3. A drive winding is disposed on the stator yoke, a rotor magnet coupled to a rotating shaft is disposed opposite to this drive winding through a predetermined gap, and a bearing supporting the rotating shaft is arranged on the rotary shaft. In a method for manufacturing a flat brushless motor disposed in a central opening formed in a stator yoke, (a) an insulating layer made of an insulating base material and an adhesive to ensure thickness is attached to a flat magnetic path. a step of adhering a metal foil onto the insulating layer, and (b) etching the metal foil to form wiring on the insulating layer attached to the flat magnetic path material. (c) obtaining the stator yoke consisting of the flat magnetic path material, the insulating layer, and the printed pattern layer for wiring by directly forming a printed pattern layer for wiring without using any other base material; , a step of arranging the drive winding on the insulating layer on which the printed pattern layer for wiring is formed; forming the center hole in the stator yoke, the center hole having a peripheral edge made of a laminated body of material and the insulating layer; A method for manufacturing a flat brushless motor, comprising the steps of: directly coupling the peripheral portion made of a laminate of the flat magnetic path material and the insulating layer to the bearing in order to arrange the bearing. 4. Using a cross-shaped material as the insulating base material and an epoxy-based adhesive as the adhesive, and forming the insulating layer from the cloth-shaped insulating base material impregnated with the epoxy-based adhesive. 4. A method of manufacturing a flat brushless motor according to claim 3.