JPS6252548B2 - - Google Patents

Description

Detailed Description of the Invention The present invention provides a frame-shaped electric machine in which a field magnet having 2m (m=1, 2,...) magnetic poles, S magnetic poles and N magnetic poles alternately spaced at equal intervals, and a conductive wire are wound into a frame shape. Regarding an axially flat disk-type electric motor in which either the field magnet or the frame-shaped armature coil group is fixed to a rotating shaft so that the child coil group rotates relative to the child coil group, The main purpose of the present invention is to make it possible to easily and inexpensively form a frame-shaped armature coil in an axially flat electric motor with a diameter of up to 40 centimeters, and to obtain various characteristics with slight changes. purpose.

It is well known that small axially flat electric motors have a flat disk-like shape and are being used in audio equipment such as cassette tape recorders and record players in place of cylindrical electric motors. Although this type of small electric motor is used in place of the cylindrical electric motor in other fields, this kind of large axially flat electric motor with a diameter of up to 40 centimeters, for example, is used in special fields. In order to form a large field magnet, a very large field magnet and a group of frame armature coils are required. In addition, expensive rotating shafts and bearings must be used. In particular, the S magnetic pole and N magnetic pole are 2 m (m = 1, 2, 3
...) It is difficult and especially expensive to form a field magnet with a diameter of up to 30 centimeters, having alternately spaced sides. diameter
This is due to the fact that the number of large, special axially flat electric motors that can reach up to 40 centimeters in length is limited. Furthermore, the frame-shaped armature coils formed for use in such large axially flat electric motors must also be formed into large pieces, so the method of forming them is also cumbersome and insufficient in terms of strength. Therefore, it is necessary to mold it in expensive plastic to make it strong enough.
Like the field magnet, it requires an expensive frame-shaped armature coil, and has the same disadvantages as using the field magnet with a diameter of up to 30 centimeters.

When forming an axially flat electric motor with a diameter of up to 40 centimeters, it is extremely expensive due to the above reasons, but due to its special nature, the production volume is also small. Since it is a unique motor compared to an electric motor, and in order to be able to obtain it at a low cost in fields that require such a large axially flat motor, it is designed to be inexpensive and highly efficient. There must be.

The present invention has been made in order to solve the above-mentioned drawbacks, and by solving this problem, it is possible to provide society with an axially flat electric motor that produces other effects that will become clear from the following explanation. Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows that the axial gap type electric motor M of the present invention is
A vertical cross-sectional view is shown as an example of a case where a field magnet (to be described later) rotates relative to a frame-shaped armature coil (ie, in the case of a brushless axially flat type electric motor). This axially flat electric motor M
For example, a disc-shaped mild steel plate 2, 3 with a thickness of 2 cm and a diameter of 40 cm is attached to a support 4 made of metal such as iron with a diameter of 4 cm.
By forming it with an appropriate gap 5, the diameter
An axially flat motor body 1 with a long radius of 40 cm is formed. Now, it is possible to form the mild steel plate 2 or 3 into a flat cup-shaped body and attach the mild steel plate 3 or 2 to the open end of this, but it is possible to form a flat cup-shaped body with a diameter of 40 cm. Forming the rotating shaft 6 is difficult, expensive, and heavy, and is inconvenient, so it is preferable to form it as described above.The rotating shaft 6 is made of iron or the like and has a diameter of 6 cm, for example. , is rotatably supported by bearings 7, 8, such as bearings, substantially perpendicular to the center of the main body 1 made of mild steel plates 2, 3. The rotary shaft 6 has a flange 9 formed at its intermediate portion, and a bearing 10 connected to the bearing 8 comes into contact with the lower part of the flange 9. For example, a diameter of 30 mm is placed on the flange 9.
A yoke 11 made of a centimeter disc-shaped mild steel plate is fixed perpendicular to the rotating shaft 6 by appropriate means. On both sides of the yoke 11 (although it may be only one side, this embodiment shows the case of both sides) around the rotating shaft 6,
For example, a donut disc-shaped field magnet 12 having a diameter of 30 cm and having 2 m (m = 1, 2, ...) S magnetic poles and N magnetic poles alternately spaced apart is attached (second (see figure). The field magnet 12 has 20 magnetic poles in which the S magnetic pole and the N magnetic pole are alternately magnetized. The field magnet 12 shown in FIG. 2 may be used as is, but the S magnetic pole, the N magnetic pole
The cost of the mold to form the field magnet 12, which has alternating magnetic poles and has a diameter of 30 centimeters, costs nearly 10 million yen, and even after this mold has been formed, The field magnet 12 is also very expensive. especially the diameter
Regarding the special axially flat electric motor M with a diameter of 40 cm, the number of units produced is small, and it is not cost-effective to use the expensive field magnet 12 with a diameter of 30 cm. This results in an axially flat electric motor M that does not have the same shape. Therefore,
In solving this problem, the field magnet 12
In forming the magnetic field, the magnetic poles forming the S magnetic pole and the N magnetic pole are formed from field magnet segments. Now the field magnet 12 is the S magnetic pole,
Assuming that there are 20 magnetic poles in which the N magnetic poles are alternately magnetized, 20 fan-shaped field magnet segments, which are divided into 20 equal parts as shown in FIG. 2, are required. However, it is also difficult to form the fan-shaped field magnet segments that form the field magnet 12 with a diameter of up to 30 centimeters, and like the field magnet 12 described above, it is expensive. Therefore, as shown in FIG. 3, a plurality of (two in FIG. 3) fan-shaped field magnet segments 12A, 12B are arranged, for example, with a radius so as to satisfy the magnetic pole width. The S magnetic pole and the N magnetic pole of the field magnet 12 are formed on the outer circumference of the rotating shaft 6 in the vertical direction by adhering or otherwise fixing them to both sides of the yoke 11 along the direction. Since such small field magnet segments 12A and 12B can be formed at low cost (in addition, although the field magnet segments 12A and 12B are composed of two field magnet segments in FIG. 3, even smaller field magnet segments 12A and 12B can be formed ), forming the field magnet 12 as described above using the field magnet segments 12A and 12B will ultimately result in an axially flat electric motor M. This is advantageous because it can be produced at a very low cost. Note that it is not necessary to use the field magnet segments 12A and 12B of the same quality.Due to the nature of a rotating motor that requires particularly strong torque in the outer circumferential direction, the field magnet segments closer to the outer circumferential direction have a higher magnetic force. When a strong magnet is used and provided, a strong torque can be obtained and the field magnet 12 can be formed at low cost. Therefore, in the field magnet 12 shown in FIG. 3, for example, a strong and expensive summarium rare earth magnet is used as the field magnet segment 12A, and an inexpensive black ferrite magnet with poor magnetic force is used as the field magnet segment 12B. It is configured using Net. The same applies to square field magnet segments 12'A and 12'B, which will be described later. The field magnet 12 or field magnet segment 12 is attached to the inner surface of the gap 5 side of the soft steel plates 2 and 3 that rotate relative to the field magnet 12 or the field magnet segments 12A, 12B.
A plurality of frame-shaped armature coils having an opening angle width that substantially matches the magnetic pole widths of A and 12B are arranged and fixed in the radial direction. In Fig. 4, field magnet 1
2 or field magnet segment 12A, 12
Two fan frame-shaped armature coils 13A and 13B having an opening angle width that substantially matches the magnetic pole width of B are arranged and fixed in the radial direction. Fan frame armature coil 13
A and 13B are formed by winding a large number of conductive wires in a fan frame shape, and fan frame armature coils 13A, For example, 13 pieces of 13B are arranged at appropriate intervals so as not to overlap one another. Field magnet segment 1
For the same reason as in the cases of 2A and 12B, a rotary motor requires particularly strong torque in the outer circumferential direction, so the closer to the outer circumferential direction, the more turns the conductive wire is used. (Square frame armature coil 13'A, 1 to be described later)
The same applies to 3'B. ). Therefore, in the case of FIG. 4, the fan frame-shaped armature coil 13A is formed by winding the conducting wire in a fan frame shape with many turns, and the coil 13B does not have the conducting wire wound so much. This makes it possible to obtain the required torque and to reduce the cost. The reason why multiple frame-shaped armature coils as described above are arranged in the radial direction is that
Forming a large frame-shaped armature coil for an axially flat electric motor, which can be as long as 40 centimeters, is difficult and not strong enough, so
A small frame-shaped armature coil can be used as a substitute (in addition, if the coil is small, the expensive plastic molding means can be made cheaper, and the frame-shaped armature coil can be made with high strength by using self-bonding wire. The field magnet segments (Example 12A, 12B) can be selected along with the child coils (for example, 13A, 13B), and the fan frame armature coils (eg, 13A, 13B) can be selected accordingly. This is to obtain an axially flat electric motor M that can obtain the desired torque at low cost by obtaining the effect.
Note that the lateral frame sides of the fan frame armature coils 13A and 13B (the same applies to the rectangular frame armature coils 13'A and 13'B described later) that do not contribute to torque generation are bent vertically to form the coils. It is convenient to shorten the distance between 13A and 13B. The field magnet 12 or the field magnet segment 12A, 1 is placed in the frame hollow portion 13a (or/and 13b) of the fan frame-shaped armature coil 13A (or/and 13B).
A magnetic sensing element 14 such as a Hall element is housed and disposed for discriminating (sensing) the S or N magnetic pole of 2B and determining in which direction the current should flow.
It goes without saying that the magnetically sensitive element 14 does not necessarily have to be housed within the frame cavities 13a, 13b. In addition, the above field magnet segment 1
FIG. 5 shows the relationship between the field magnet 12 consisting of 2A and 12B, the fan frame armature coils 13A and 13B, and the magnetic sensing element 14. In the above case, the fan-shaped field magnet segment 1
2A and 12B are also special shapes in a sense, and in some cases it is required to make a mold for them, so as shown in Fig. 6, a rectangular (plate) field magnet is used. Magnet segment 12'
A, 12'B are formed of two (or more) in the radial direction to satisfy and fit the magnetic pole width, and are made of a wide, strong magnetic force, expensive summarium, or rare earth magnet. The rectangular field magnet segment 12'A is placed in the outer circumferential direction, and the rectangular field magnet segment 12'B, which is made of a narrow rectangular and inexpensive ferrite magnet with poor magnetic force, is placed in the inner circumferential direction. It is located in Furthermore, when using such rectangular field magnet segments 12'A and 12'B, the field magnet A rectangular frame armature coil 13'A is formed by winding a conductive wire in a square (rectangular) shape with many turns as shown in FIG. 7 so that the magnetic pole width approximately matches that of the net segments 12'A and 12'B. , 13'B may also be used. The field magnet segments 12'A, 12'B and the armature coils 13'A, 13'B are connected to the field magnet segments 12A, 12B and the armature coil 13.
It is convenient to arrange and form under the same conditions as A and 13B. It goes without saying that the same principle holds true even when the armature coil is used as the rotor and the field magnet is used as the stator (brush motor).

Since the axial flat type electric motor of the present invention is realized with the above configuration, when the magnetic sensing element detects a predetermined magnetic pole, current is passed in an appropriate direction to an appropriate armature coil, and Fleming's left-hand rule is applied. Therefore, the rotor rotates in a predetermined direction. To explain with reference to FIG. 8, when the voltage is constant, the two armature coils 13A,
When the armature coils 13B are connected in parallel and energized, the number of revolutions (N) and the torque (T) can be large (indicated by slope line A), and the armature coils 13
When only one of the armature coils A or 13B is energized, the rotation speed is N as shown by the slope line B, but the torque can be T/2, and when the armature coils 13A and 13B are connected in series, Both rotational speed and torque are N/2 and T/2, respectively, as shown by slope line C.
It can be set to 4. As described above, it is possible to obtain an axially flat electric motor having various characteristics with only slight wiring and connection changes.
Furthermore, as described in the previous section, there is an effect that a frame-shaped armature coil used in a radially long axially flat electric motor can be easily and inexpensively formed.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of the axially flat motor of the present invention, FIG. 2 is a plan view showing an embodiment of the field magnet of the present invention, and FIG. 3 is the field magnet of FIG. FIG. 4 is a plan view showing another method for forming a magnet, and FIG. 5 is a plan view showing the shape and arrangement of a frame armature coil according to an embodiment of the present invention. 6 is an explanatory diagram showing the relationship between the field magnet or the field magnet segment, the frame armature coil, and the magnetic sensing element, FIG. 6 is a plan view showing an embodiment replacing FIG. 3, and FIG. FIG. 8 is a plan view showing an embodiment replacing FIG. 4, and FIG. 8 is an explanatory view for showing the effects of the present invention. M... Axial flat electric motor, 1... Axial flat electric motor main body, 2, 3... Disc-shaped mild steel plate, 4...
...Strut, 5... Gap, 6... Rotating shaft, 7, 8...
Bearing, 9... Flange, 10... Bearing, 11... Yoke, 12... Field magnet, 12A, 12B,
12'A, 12'B...Field magnet segment, 13A, 13B...Fan frame armature coil, 1
3'A, 13'B...Square frame armature coil.

Claims (1)

[Claims] A frame-shaped armature coil group formed by winding a field magnet having 12 m (m=1, 2,...) magnetic poles with S magnetic poles and N magnetic poles alternately spaced at equal intervals and a conductive wire in a frame shape. In an axially flat electric motor, in which either the field magnet or the frame-shaped armature coil group is fixed to a rotating shaft so that the magnetic poles of the field magnet and the frame-shaped armature coil group rotate relative to each other. An axially flat type electric motor, characterized in that the frame-shaped armature coil is formed with an opening angle width that substantially matches the width of the frame-shaped armature coil, and a plurality of frame-shaped armature coils are arranged in the radial direction of the frame-shaped armature coil. 2. The axially flat electric motor according to claim 1, wherein the frame-shaped armature coil has a fan frame shape. 3. The axially flat electric motor according to claim 1, wherein the frame-shaped armature coil has a rectangular frame shape. 4. The axially flat type electric motor according to claim 1, wherein the frame-shaped armature coil is formed by winding a conducting wire with a larger number of turns as it approaches the outer circumference. 5. Claims 1 to 5, characterized in that the field magnet is formed by arranging a plurality of field magnet segments so as to fit within a magnetic pole width of 1/2 m. The axially flat electric motor according to any one of Item 4. 6. The axially flat electric motor according to claim 5, wherein the field magnet segment is fan-shaped. 7. The axially flat electric motor according to claim 5, wherein the field magnet segment is square. 8. The axially flat electric motor according to any one of claims 5 to 7, wherein the field magnet segments have stronger magnetic force as they are closer to the outer circumference.