JPS60156254A - Disc type brushless motor with one armature coil for flowing one phase - Google Patents

Abstract

PURPOSE:To inexpensively manufacture a brushless motor in a mass production by plastic-molding an armature coil and an IC for a drive circuit to form in a plastic plate-shaped armature body. CONSTITUTION:An armature coil 4 is plastic-molded in a plastic plate-shaped armature body. In the coil 4, conductor units 4a, 4b which contribute to the generating torque have a length of approx. diameter of a field magnet, and are formed in a rectangular frame shape having an opening angle width substantially equal to that of a field magnet. An IC6 for a drive circuit is disposed to position a magnetoelectric transducer 5 except the occupying position of the coil 4 of uniform condition with the unit 4a which contributes to the generating torque 7 of the coil 4. The coil 4 and the IC6 are plastic-molded to form a plastic plate- shaped armature 1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a disc-type brushless motor having one armature coil and which is energized in one phase.

BACKGROUND ART Conventionally, with the advent of various devices such as office machines, there has been a demand for disk-type brushless motors, especially fan motors, suitable for these devices.

Such disk-type brushless fan motors are required to be relatively inexpensive, small, and extremely flat, depending on the device to which they are applied.

Here, the one that most satisfies this condition is a disk-type brushless fan motor that has one armature coil and one position detection element, and is energized in one phase.
In the past, although it was possible to rotate the magnet rotor over a predetermined range, it was not possible to rotate it continuously with a strong rotational force, so it was impossible to construct a disk-type brushless fan motor. Furthermore, even if one armature coil can rotate a motor for one position detection pin, a strong rotational force cannot be obtained with only one armature coil. For this purpose, it is necessary to use two or more armature coils.

Here, in a disk type brushless fan motor having two armature coils as a stator armature, two position detection elements are required.

Here, a magneto-electric transducer such as a Hall element or a Hall IC is often used as the position sensing element, but since this position sensing element is expensive, it is preferable to use only one piece because it is inexpensive and small. This is preferable in that the disk type brushless fan motor can be mass-produced. However, when there is only one position detection element, this element detects the boundary between the N and S poles of the field magnet, that is, the dead point, when the motor is started, as in the case of one coil described above. It has the disadvantage that it cannot be started automatically.

In the above case, reducing the number of armature coils from two to one to reduce the rotational torque will result in an inefficient disc-type brushless fan motor, so the number of armature coils is reduced to two, which can be formed at low cost. In order to achieve this, it is desirable to reduce the number of position sensing elements from two to one, and to create a disk-type brushless fan motor that can self-start even with one position sensing element.

For this purpose, the applicant first filed Utility Application No. 58-28958.
No. 58-56.659 eliminates the situation where the position sensing element detects a dead point when the magnetic rotor is stopped or started, and the magnetic rotor always generates coking when stopped. 3. One inexpensive and useful position sensing element that can be configured to move to a state where it can be activated and then stop. We provided a coreless disk-type brushless fan motor with two armature coils.

Such a coreless disc type brushless motor uses two armature coils, so if these two armature coils are not placed in the correct position, the disc type brushless motor will have poor rotational balance. There is a fear. Also, compared to the case of one armature coil, in the case of two armature coils, the number of winding steps is increased by one armature coil, making it more expensive, and the soldering process increases by two steps ( One armature coil has a total of two terminals, a winding start terminal and a winding end terminal, so it is necessary to solder these two terminals to the specified locations on the printed circuit board.) However, it becomes troublesome in mass production,
The drawback is that it becomes an expensive disk-type brushless fan motor. Also, with the advent of various office machines, there is a demand for extremely thin brushless fan motors that can handle low airflow. There was a drawback that it was not possible to form a motor.

In addition, in the case of conventional coreless disc type brushless fan motors, if the armature coil coil energization control circuit components are exposed, the armature coil may come off due to external shocks or wind pressure due to fan rotation. There is a risk that this will happen. Furthermore, the temperature characteristics of electrical circuit components may deteriorate due to wind generated by rotation of the fan or the like. Furthermore, the wind may hit the armature coil or electric circuit components, causing a large rotational noise. The present invention was made in order to solve the above-mentioned drawbacks of the conventional armature coils. )
To overcome the difficulty of positioning armature coils and to form a disc-type brushless (fan) motor with good rotational balance, and to enable rapid placement of armature coils. (2) ) By forming one armature coil with a shape that can generate the same rotational torque as the conventional armature coils that required two, the armature coil can be formed at a low cost with fewer assembly steps. (3) To reduce the number of man-hours required for soldering the terminals of the armature coil (so that it can be mass-produced at low cost); The circuit is made into an IC, so that it is smaller and less than the thickness of the armature coil, so that it can be installed with plenty of space in the remaining space on the printed circuit board of the single armature coil. To enable a stator armature having an armature coil to be made into a disc-shaped one with a small thickness; (5) to enable self-starting even with one position sensing element, and to form an inexpensive disc-type brushless motor. (6) To facilitate the positioning of the magnetic material for coking generation; (7) By molding at least the armature coil and the IC for the drive circuit in plastic, it is possible to prevent the armature coil from coming off and for the drive circuit. IC
By preventing changes in temperature characteristics and the generation of large rotational noise, it is possible to mass produce ultra-thin, coreless, high-performance disc-type brushless fans at low cost that have never been seen before. This was done for the purpose of doing so.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a longitudinal sectional view corresponding to the line X--X shown in FIG. 4 of a disc-type brushless fan motor FM that is energized in one phase.

Reference numeral 9 denotes a square case for a cup-shaped disk-type brushless fan motor made of a magnetic material that is flat in the axial direction, as shown in FIG. The peripheral part has a protruding body 9a extending upward. Bearings 11, 12 are provided at the openings at both upper and lower ends of the inner peripheral part of the through hole 10.
is provided.

A rotary shaft 13 is rotatably supported by the bearings 11 and 12 approximately at the center of the main body of the disc-type brushless fan motor FM. At the bottom of the rotating shaft 13 is a pull-out stopper E.
IJ ring 14 is installed. Reference numeral 21 indicates a recessed portion of the case 9 (see FIG. 2), and 22 indicates an air passage hole provided at the bottom of the case 9.

23 is the stay, 24-1 and 24-2 are the positive power cord and negative power cord, respectively. Reference numeral 9b denotes a post made of a non-magnetic material provided on the cup body 9, and another post 9b made of a non-magnetic material (not shown) is also provided at a 180-degree symmetrical position. At the top of this support column 9b, an armature coil 4. Boss 3 and drive circuit IC made of non-magnetic material
An annular plastic plate-shaped armature body 1 (see FIG. 6) formed by plastic-solding 6 is fixed by a cogging generating screw 15 made of a magnetic material.

A strong magnetic field can be obtained by disposing a stator yoke on the lower surface of the plastic plate-shaped armature body 1, and a magnetoelectric transducer 5 used as a position detection element (described later) is used as a drive circuit IC 6 (described later). Since the output from the motor (which is configured to be included in the motor) becomes a square wave, and the armature coil 4 is energized in a square wave, the energization changes abruptly, producing a loud rotating noise that is unpleasant to the ears. . for that.

Without using a stator yoke, the output of the magnetoelectric transducer 5 is smoothed into a sine wave, and the armature coil 4 is energized in a sine wave to avoid generating large rotational noise. Because a stator yoke is not used, there is a risk of not being able to obtain a strong magnetic field, so by changing the winding specifications of the armature coil 4, less current is required, and the disk-type brushless fan motor FM, which has increased rotational noise, can be improved. Obtained.

One armature coil 4 disposed as shown in FIG. 4 is molded into the plastic plate armature body 1. As shown in FIG. The armature coil 4 has a conductor portion 4 as 4'' that contributes to the generated torque and is connected to a field magnet 2, which will be described later.
It has a length approximately equal to the diameter of the field magnet 2, and has a rectangular frame shape with an opening angle width substantially equal to the opening angle of the field magnet 2. That is, the armature coil 4 has a center point 7 on the center line 16 of the conductor section 4a that contributes to the generated torque on one side and a center line 16' of the conductor section 4a/ that contributes to the generated torque on the other side.
The opening angle with the upper center point 7' is the opening angle width of the field magnet 2, that is, the opening angle of the field magnet 2 is N as shown in FIG.
, It has an annular 8-pole structure with alternating S magnetic poles, and one of the N or S magnetic poles has an opening angle of 45 degrees, so the opening angle width is substantially 45 degrees. It belongs to As shown in FIG.
A single armature coil 4 as shown in FIG. 4 is arranged and molded in plastic.

A plastic plate-shaped armature body 1, which is plastic-molded with the single armature coil 4 disposed as shown in FIG. 4, faces the field magnet 2 as shown in FIG. . When the above-mentioned armature coil 4 is arranged as shown in Fig. 4, the armature coil 4
On the surface where the armature coil 4 is arranged, there is sufficient space for arranging electrical components outside the occupied position of the armature coil 4. Therefore, on the surface of the space for arranging the electrical components, a drive circuit IC 6, in which the magnetoelectric transducer 5, which is a position detection element, and a drive circuit are formed as an integrated circuit, is installed in a 1-to-1 construction as shown in FIG. ,
1. Yo2, Wa, □4 /L= 417) Yoka Because the conductor portion 4b in one direction does not contribute to the generated torque.

It is also possible to use a magnet rotor 2 whose radius is smaller by the width of the conductor portion 4b. The magnetoelectric conversion element 5 such as a Hall element or Hall IC as a position detection element is located at the conductor portion 4a or 4a' which contributes to the generated torque (in this case, the most correct position is the center line 16 or 16'). It is better to place the element 5 above the magnet rotor 2 and the armature coil 4, but since this increases the thickness by the amount of the element 5,
) The air gap increases, making it impossible to obtain strong torque, and the arrangement is extremely troublesome, making it unsuitable for mass production.

Therefore, as will be explained further below, the magnetoelectric transducer 5
It is preferable that the conductor portion 4a of the armature coil 4 is disposed outside the occupied position of the armature coil 4 under equal conditions with the conductor portion 4a that contributes to the generated torque of one side of the armature coil 4. Therefore, the drive circuit IC 6 is arranged as shown in FIG. 4 so that the magnetoelectric transducer 5 is located at this position. The boss 3 is made of metal made of non-magnetic material, and is cup-shaped with a through hole formed at the bottom for passing the screw 15. The armature coil 4 and the drive circuit IC 6 are made of plastic. When the plastic plate armature body 1 is formed by molding, the boss 3 is also molded into plastic at the same time. By integrally molding the boss 3 with plastic, a hole is formed in the plastic plate-shaped armature body 1 for attaching the coking-generating magnetic material (see FIG. 6). That is, a hole 17 is formed into which the coking generating screw 15 is inserted. The position of the boss 6 is plastic molded at a position of the plastic plate armature body 1 suitable for screwing the coking generating screw 15. Therefore, the position of the coking generating screw 15 will be explained below.

The screw 15 made of the magnetic material is approximately one-fourth from the conductor portion 4a that contributes to the torque generated by the armature coil 4 in the direction of rotation of the magnet rotor 2 (direction of arrow A...see FIG. 4). The magnetic pole width (11° to 25°) is preferably screwed to the front position of the plastic plate-shaped armature body 1. The plastic plate armature body 1 is attached to the support column 9b by the screw 15.
It is fixed to the top surface of the screw 15, and the amount of coking force generated can be easily adjusted by adjusting the threading degree of the screw 15. This screw 1
5 causes coking, even if the magnetoelectric conversion element 5
The rotor can be started automatically even with just one rotor. That is, by forming the coking-generating magnetic material by the screws 15 on the plastic plate-shaped armature body 1, the magnet rotor 2 is attracted to the screws 15, and the magnet rotor 2 is placed at a position where it can self-start. By forming the screw 15 at the above-mentioned position so that the magnetoelectric transducer 5 stops at a position where no dead point is detected when the motor is started,
Even if there is only one magnetoelectric conversion element 5, the one-coil, one-phase disk type brushless fan motor FM can be started automatically. Furthermore, as mentioned above, since the column 9b (not shown) is also provided at a position 180 degrees symmetrical to the column 9b,
A screw 15' is also screwed at a position 180 degrees symmetrical to the screw 15. Dotted line enclosure 28. . . , 31 indicates other positions suitable for rounding the screws P15, 15' to generate coking. In the case of Fig. 4, there are two other positions suitable for causing coking, but in this case, the positions overlap the armature coil 4, which is not very preferable. The position is not shown in FIG.

Next, the reason why the coking-generating magnetic bodies formed by the screws 15 and 15' are provided at the above-mentioned positions will be explained. The position where the maximum starting torque is generated is the position of the conductor 84a or 48', which contributes to the torque generated by the armature coil 4. Therefore, it would be better to install the screws 15 and 15' at this position, but it is difficult to arrange them at this position, and if the maximum starting torque is applied in advance at the time of start-up, the loss at the time of start-up will result in the highest efficiency. is not obtained.

Therefore, if the magnet rotor 2 moves even a little, the coking is generated by the screw 15.15 at a position just before the conductor part 4 at 4'' that contributes to the generated torque by the above-mentioned condition so that the maximum torque can be generated. The stop position of the magnet rotor 2 is always set to the best starting position so that the screw 15 or 15' is located at the center of the N pole or S pole of the magnet rotor 2. The head of the screw 15° and 15' is at the center of the magnetic pole of the magnet rotor 2, and the thickness is such that it can always be stopped and can be started easily.
It is convenient to use a strong one.

As described above, the armature coil 4 is molded into a plastic mold and the upper surface of the plastic plate armature body 1 has a fan-equipped cup formed of flat plastic in the axial direction as shown in FIG. The bodies 20 are facing each other. 2
Reference numeral 5 denotes a fan integrally formed on the outer circumference of the fan-equipped cup body 20. A boss portion 26 is integrally formed approximately at the center of the inner surface of the cup body 20.
The upper end of the rotating shaft 13 is fixedly attached to the rotating shaft 13 so that the rotating shaft 13 rotates integrally with the rotating shaft 13. An annular rotor yoke 27 is fixed to the inner surface of the cup body 20.

The lower surface of the rotor yoke 27 has an N, as shown in FIG.
An annular 8-pole magnet rotor (field magnet) 2 having alternating mh of S is fixedly installed to face the plastic plate-shaped armature body 1 .

The drive circuit IC 6 is formed on a space surface where the armature coil 4 is not provided so as to be lower than the height of the armature coil 4. The reason why such a thick IC 6 for the drive circuit is used is that if the IC 6 is thicker than the armature coil 4, the air gap between the magnet rotor 2 and the armature coil 4 will be increased by the thickness. As the magnetic flux increases, it becomes impossible to obtain a strong magnetic flux corresponding to the increased air gear.

Therefore, as described above, the drive circuit IC 6 is formed to be thinner than the armature coil 4. On the bottom surface of the plastic plate armature body 1.

The terminals of the drive circuit IC 6 are exposed, and a printed pattern for connection using a conductor is formed on the bottom surface of the plastic plate armature body 6, and the pattern and the terminals of the drive circuit IC 6 are soldered. are doing.

FIG. 7 is a perspective view of a plastic plate armature body 1' showing a second embodiment of the present invention, in which an iron piece 52.52' is used instead of the cogging screw 15, and the iron piece 32.32' is In order to be able to form the screws 15 and 15' in the same position, plastic molding is performed at the same time when the plastic plate armature body 1' is formed. 3
Reference numeral 6 designates a screw insertion hole for fixing the plastic plate-shaped armature body 1' to the upper surface of the support column 9b by screwing it onto the support column 9b using a screw (not shown) made of a non-magnetic material.

Another example is the screw 15.15' or the iron piece 32.3.
When molding the plastic, plastic is molded so as to form a screw hole at a position of the plastic plate armature body 1' suitable for providing a screw 15, 15' made of a magnetic material in the screw hole. You may also screw it on.

As is clear from the above, the disk-type brushless motor of the present invention has the following features: (1) Since it is a coreless type, there is no coking that would impede the performance of the motor, and since it is coreless, it can be extremely light in weight. (2) Since there is only one armature coil, there is no difficulty in alignment, and the armature coil can be placed in the correct position, making it easy to obtain a disk-type brushless motor with good rotational balance. (3) Even with one armature coil, an efficient disc-type brushless motor can be achieved that has the same rotational torque as the conventional one that required two armature coils. (4) Note that there is only one armature coil, compared to conventional ones, the number of steps required for soldering the terminals of the armature coil can be reduced, resulting in faster production.
) Even with just one position sensing element and armature coil, by generating coking at the most suitable position, dead points are eliminated, allowing self-starting and stable rotation. (6) There is no need to use a stator yoke, etc., and the number of parts is very small, such as one armature coil, so disc-type brushless motors with good performance can be mass-produced at low cost. (7) Armature coils and Since there is no need to expose the drive circuit IC, it is possible to prevent the armature coil and drive circuit IC from coming off due to external shocks, and from changing the temperature characteristics of the armature coil and drive circuit IC. (8) This has the effect of making it easier to position the coking-generating magnetic material.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a disk-type brushless fan motor shown as an example to which the present invention is applied, FIG. 2 is a perspective view of the case of the fan motor shown in FIG. 1, and FIG. 3 is a cup with a fan shown in FIG. 1. FIG. 4 is a plan view of an armature coil forming a stator armature as an embodiment of the present invention used when an 8-pole magnet rotor is used;
Figure 5 is a bottom view of the 8-pole magnet rotor. FIG. 6 is a perspective view of a plastic plate-shaped armature body, and FIG. 7 is a perspective view of a plastic plate-shaped armature body as a second embodiment of the present invention. FM...Disc type flangeless fan motor, 1.1
'...Plastic plate armature body, 2...Mag 1
5.15'...Screw made of magnetic material to generate coking. Patent applicant figure 3 figure 5 erased figure 4 figure 6 figure q

Claims (1)

[Claims]: 1) An 8-pole magnet rotor having N and S magnetic poles alternately, and an opening angle of a conductor portion that contributes to the generated torque and has a length about the diameter of the magnet rotor. One rectangular frame-shaped armature coil formed with an opening angle width substantially equal to the magnet (- width) is placed on the fixed side facing the magnet rotor with its substantially center portion and central axis aligned. The magnetic rotor is fixedly installed at a position approximately one-fourth of the magnetic pole width of the magnetic rotor from the conductor portion that contributes to the generated torque of the armature coil with respect to the rotational direction of the magnetic rotor, or at a position substantially equal to the position. A piece of magnetic material for coking generation is fixedly installed at uniform positions, and is formed on the armature coil installation surface outside the occupied position of the armature coil so as to be lower than the height of the armature coil. In a disk-type brushless motor that is energized in one phase and has one armature coil equipped with a drive circuit IC including a position detection element, at least the armature coil and the drive circuit IC are molded in plastic to form a plastic plate armature. A disk-type brushless motor with one armature coil that is energized in one phase. (2) The plastic plate-shaped armature body also has the coking-generating magnetic material simultaneously molded in plastic. 3)
The plastic plate-shaped armature body is the coking electric disc type brushless motor. (4) A disk type with one armature coil and one phase current according to claim 13, characterized in that a boss made of metal is molded in plastic on the inner periphery of the hole. brushless motor. (5) The disc-type brushless motor according to claim (3), wherein the hole is a screw hole. (6) The coking-generating magnetic material attached to the hole is a screw made of a magnetic material for attaching the plastic plate armature body to the stationary side. ) or (5) armature coil 1
1-phase energized disc-type brushless motor,