JPS60153495A - Flat type electric fan - Google Patents

Abstract

PURPOSE:To make compact a flat axial-flow fan, which is driven by a semiconductor motor, by making up the fan of a circular flat base plate, a base plate integrally provided with plural arms, an armature coil and a magnet rotor. CONSTITUTION:A first base plate 1 of plastic, arms 10a-10d of plastic and a second base plate 1e of plastic are provided as a flat board. An armature coil and a magnet rotor 6 are secured on the base plate 1 in the circumferential direction of an electric fan. A plastic ring 9 serves as a protective cover for fan blades 8a-8c, which are rotated synchronously with the magnet rotor 6. For that reason, the ring 9 and an extending portion 9b can be manufactured by injection molding and fitted on the base plates 1, 1e to simplify the manufacturing process of the electric fan. This results in providing the electric fan which is driven by a semiconductor motor which is as compact and flat as possible.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flat electric fan that is driven.

Electric fans, which are called axial flow fans and whose outer diameters range from about 5 centimeters to about 10 centimeters torr, are well known.

In particular, the demand for electric fans that use DC semiconductor motors as their drive source has increased significantly in order to increase efficiency and make it easier to supply power from the DC power source of devices to which they are installed (computers, copy machines, etc.). ing. In addition, there are many products that are compatible with these.

However, due to the trend toward smaller and flatter devices, axial fans are also required to be flatter. In addition, it is also required to be lightweight and to be supplied at low cost.

In order to satisfy the above requirements, a coreless TISF type electric motor is optimal, but it requires an increased number of man-hours and is expensive, making it impractical.

The device of the present invention is characterized in that it eliminates the above-mentioned drawbacks and also provides an electric fan that uses this type of semiconductor motor as a drive source, which is as small and flat as possible.

Next, the details will be explained with reference to FIG. 1 and subsequent figures.

FIG. 1 is a cross-sectional view of the apparatus of the present invention, and FIG. 2 is a diagram similarly viewed from the top, where the same symbols represent the same members.

The first substrate 1 made of plastic, the arms 10 a , 10 b % 10 c, 10 d extending around the outer periphery of the first substrate 1 and the second substrate 1 e are molded as one piece of plastic, or a flat plastic plate is molded into a desired shape. It is punched and processed. The cross section in FIG. 1 is the cross section taken along the dotted line H in FIG. The first and second substrates 1.1e have the same symbol and the third
As shown in the figure.

In FIG. 3, fan-shaped coils 12a and 12b whose conductor portions have an opening angle of 90 degrees are fixed on a substrate 1 in a 180-degree vertical orientation.

The cylinder 3 serving as a bearing is inserted into the central hole of the substrate 1, and is made of glass nuc material (
AXB (indicated by a dotted line), it is molded and fixed as one body with the substrate 1.

An oil-less metal or ball bearing is housed inside the bearing cylinder 3, and a rotating shaft 4 (shown in the first diagram) is inserted through the hole 4b.

Further, the magnet 13 is magnetized to NX 8 as shown in the figure and fixed onto the substrate 1 at the same time as the above-described molding.

The direction of the magnetic poles N and S is the circumferential direction.

Symbols 14a, 14b, and 14c are printed wiring, and the conductor portion 14e includes an armature coil 12a,
A common terminal of the armature coils 12b is connected to the conductor portions 14a, 14b, and other terminals of the armature coils 12a, 12b are connected to the conductor portions 14a, 14b. This connection is made by soldering, and is done before the above-mentioned plastic molding. The conductor portions 14as 14b and 14c are connected to the arm 10.
a and is connected to an armature current distribution circuit F (indicated by a dotted line, details of which will be described later with reference to FIG. 5).

This portion is schematically indicated by dotted lines C and DXE.

The conductor parts (parts of the printed wiring) that become the terminals with symbols 15a, 15b, and 15c are the input terminals for the power supply positive terminal and the terminals for rotation detection in the circuit shown in Fig. 5, but the details will be described later. .

Symbols a, lb, and lc are holes for screwing the substrate 1.1e to other equipment. If necessary, screw holes can be provided in the ring 9 as shown in FIG.

Returning to Fig. 1.2, at the top of the rotating shaft 4 is a soft body 1 disc 5.
A circular ferrite magnet 6 is fixed on the back surface of the ferrite magnet 6, and its magnetic field is applied to the armature coil (indicated by symbols 12a and 12b in Fig. 3) contained in the plastic molded body indicated by symbol 2. ) is inserted. Symbol 4a is a sleeve that fixes the rotating shaft 4. Dotted line 3
a is a thrust bearing of the rotating shaft 4.

A plastic ring 7 is fitted onto the outer periphery of the magnet rotor 6 from above, and on the outer periphery are plastic fans 8a, 8b8C1... made in one piece.
... (schematically indicated by dotted lines in FIG. 2) is provided and rotates in synchronization with the magnet rotor 6.

The symbol 9 is a plastic ring located outside the rotating outer diameter of the fans 8a18b,...
It serves as a protective cover for the fan. A hole (not shown) on the left side of the ring 9 has a protrusion 1 of the arm 10c110d.
1b and lla are fitted and fixed.

Further, a protrusion (not shown) on the right lower edge of the ring 9 is fitted into the hole 1d shown in the third figure, thereby fixing the ring 9.

With the above configuration, the ring 9 is connected to the right extension 9b.
At the same time, the substrate 1. Since it can be fitted onto the LE, the process can be simplified. The portion indicated by the symbol 9g in FIG. 2 is the lower bent portion. Furthermore, arms lQa, 1Ob
In some cases, a bent portion is provided in the longitudinal direction of the arm to strengthen the arm.

Symbols 9a, 9b, 9C1... are holes provided in the ring 9, and as the fan rotates, air flows out through the holes, resulting in armature current distribution as explained in Fig. 3. Circuit F
It has a cooling effect.

Moreover, since only the device shown in FIG. 3 can be mass-produced separately, there is an advantage that mass-production can be carried out at low cost. It is produced separately into three parts together with the Macnet rotor 6 and the ring 9, and has the feature that it is easy to assemble the three parts.

It can also be made by other means. Arm 10a with printed wiring The second i-board 1e and the arm 10b are made of plastic plates, and the armature coils 12a, 12b,
After fixing the bearing 3 and completing the printed wiring, the injection shown in Fig. 4 is the magnet rotor 6,
It is a developed view of armature coils 12a and 12b. Moreover, what is shown in FIG. 5 is an armature current distribution circuit diagram of armature coils 12a and 12b. The rotation principle will be explained using both of them together.

Due to the presence of the magnet 13, the stopping position of the magnet rotor 6 is regulated.

The magnet rotor 6 rotates to the right (in the direction of arrow G) as driving torque is generated, and stops after rotating by 1/2 of the magnetic pole width. If the vehicle deviates from this stopping point to the left or right, a return torque is obtained, resulting in a stable stopping point.

When stopped due to inertia, if the motor exceeds the above-mentioned stopping point and rotates further to the right, the width of the magnetic pole is exceeded, and the torque in the left and right direction is applied again to the child machine, and the stopping point is obtained.

However, at this stopping point, torque is generated in the same direction as the Macnet rotor 6 shifts from side to side, so it rotates to either the left or right and is unstable. In other words, it becomes an unstable stopping point. Therefore, if there is only a small frictional load at the time of startup, as with the Denru J1 fan, there is no chance of stopping at an unstable stopping point, so the fan always stops at a stable stopping point.

If a piece of mild steel indicated by symbol 13a is fixed to the armature side,
Cogging generates a torque that rotates to the left or right at the unstable stopping point mentioned above, so the magnetic rotor 6 does not stop at an unstable stopping point, but stops at a stable stopping point. It can be regulated to do so. According to actual measurements, the magnet 13 has a north pole or a south pole.
Rotation in the desired direction is more reliably achieved when a single pole faces the magnet rotor.

In FIG. 5(a), when the electric switch 18 is closed,
Power is supplied from the power supply positive electrode 17, and the charging current of the capacitor 19 energizes the base of the transistor 20a,
Armature coil 12a is energized. Therefore, the magnet rotor 6 in FIG. 4 (already stopped at a stable stopping point) is driven in the direction of arrow G. As the armature coil 12b is driven, an induced output in the direction of the arrow is generated, so that a base current of the transistor 21a is obtained and conducts the transistor 21a. Therefore, the base input of the transistor 20a is obtained, and the armature coil 12a is kept energized.

When entering the next non-magnetic field zone, the induced output of the armature coil 12b disappears, so the transistor 20a becomes non-conductive. However, when entering the next magnetic field, the armature coil 12a
Since the induced output in the direction of the arrow is obtained, the transistor 21
bX20b are both energized and conductive. The armature coil 12b is therefore energized and a subsequent drive torque in the same direction is obtained.

As described above, the semiconductor motor is a semiconductor motor that generates drive torque by automatically alternating the energization of the armature coils 12a and 12b.

The driving means according to this embodiment has the following effects compared to known means.

First, even if the power supply voltage fluctuates, the transistors 21a,
Since this does not affect the swinging operation of 21b, the operation is stable. In this respect, it has superior characteristics compared to means using known flip-flop circuits.

Second, if the fan is forced to stop due to an accident,
The motor stops, but at this time, the transistor 20a
, 20b become non-conductive at the same time, automatically preventing burnout of the armature coil.

Thirdly, the voltage charged in the capacitor 22 can be taken out from the terminal 22a via the diode, and this voltage is proportional to the rotation speed. Therefore, the rotational speed of the electric motor can be controlled using the output of the terminal 22a.

Furthermore, by adding the circuit shown in FIG. 5(b),
When the system stops due to an accident, an alarm can be issued or the power supply to the cooled equipment can be stopped.

In FIG. 5(b), the input of the terminal 18b becomes the output of the terminal 18a of FIG. 5(a). The input to the terminal 22b is the output from the terminal 22a in FIG. 5(a).

When the electrical switch 18 is closed, the input at terminal 18b goes high and the input at terminal 22b goes low.

Since the output of the inverting circuit 24 is at the no-y level, the output of the AND circuit 23 is also at the no-y level. However, due to the action of the capacitor v25, the output of the terminal 23a is held at a low level. When the electric motor starts rotating, the input to the terminal 22b becomes high level, so the output of the AND circuit 23 changes to low level, and the output of the terminal 23a is maintained at low level.

When the fan is stopped due to an accident, the output of the terminal 22b changes to a low level, so the output of the AND circuit 23 becomes a high level, and after a predetermined time, the output of the terminal 23a changes to a high level. Utilizing this conversion signal, it is possible to obtain a safety device that generates an alarm or stops power supply to the device to be cooled. Terminal 15Q in FIG. 3 indicates the terminal 23a.

It is possible.

Also, the magnet rotor 6 shown in FIG. 4 has four poles, but it has eight poles.
The invention can also be practiced with poles. And yet another 1
It can also be operated as a two-phase motor by adding phase armature coils.

As can be understood from the above description, according to the present invention, the object stated at the beginning is achieved and the effects are significant.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the device of the present invention, FIG. 2 is a front view thereof, FIG. 3 is an explanatory diagram of the board (armature), and FIG.
A developed view of the magnet rotor and armature coil, and FIG. 5 each show an armature current distribution circuit diagram. 1.1e...Substrate, 1a, 1b, 1c, 1d-
Hole, 2... Plastic molded body, 3.3a... Bearing, 4... Rotating shaft, 5... Mild steel disc, 6... Magnet rotor, 7.8a, 8b, 8c, 8d... Fan, 9... Farm insurance ring, 9a, 9b, 9d... Hole, 10 a, 10 b, 10 c, 10
d-7-me, 11a, llb... protrusion, 13.
... Magnet, 13a... Mild steel piece, 4 b -
...Vacancies, 14a, 14b, 14c. C, DXE...Printed wiring, 12a, 12b...
・Armature coil, 15a% 15b, 15c... Leading terminal F... Armature current distribution circuit, 20a, 20
b, 21a, 21b...transistor, 19.22.
... Capacitor, 17... Power supply positive electrode, 18... Electric switch, 23... AND circuit, 24... Inverting circuit. Number of patent applicants 3 Figure 4 Figure 5 (α) (J)

Claims (1)

[Claims] A circular flat plate-shaped plastic first substrate, a plurality of arms protruding outward from the substrate and made as a single body, and a protruding end portion of one of the arms as a single body. a second board made, a one-phase armature coil consisting of an eleventh second coil fixed to a predetermined position on the first board, and a first
1 Connect the three sets of lead-out wires of the common terminal and other terminals of the second coil,
a printed wiring led out to the second board via the arm portion, and a device for distributing armature current to the printed wiring;
a rotating shaft rotatably supported by the bearing device; a mild steel disk fixed to the upper end of the rotating shaft with the center thereof perpendicular to the rotating shaft; A magnet rotor which is fixed axially symmetrically, has an annular shape and is magnetized in the axial direction with equal pinch of N and S magnetic poles, and the magnetic field penetrates the armature coil described above, and the rotor is crowned from above. A plurality of flaps 7 are fixed to protrude from the outer circumference of the circular ring.
7, and is made of plastic molded into a ring shape so as to protect the rotating outer periphery of the fan, and is fixed to the above-mentioned arm and a part of the second board by a retaining part provided at its lower end. A flat electric fan characterized by being composed of a protective ring.