JPS6135393B2 - - Google Patents

Description

[Detailed Description of the Invention] <Technical Field> The present invention relates to an electric fan that is provided with a dedicated oscillation motor in addition to a fan motor for blowing air, and uses this oscillation motor as a driving source, and particularly relates to the internal structure of the head of the electric fan. It is something.

<Prior art> In conventional electric fans, the drive shaft of the fan motor that drives the fan protrudes toward the back side, and a swinging mechanism consisting of a crank and rod is connected to this drive shaft via a speed reduction mechanism to drive the fan motor. It used force to make the head shake.

The structure of a conventional electric fan will be explained using FIGS. 12 and 13. As shown in FIGS. 12 and 13, a motor 6a having a stator 3a and a rotor 4a housed in a case 5a is mounted inside the motor cover 2a of the head 1a of the electric fan.
The rotor shaft 7a of a is supported by the bearing 8a of the case 5a, and the tightening tongue shaft 7a rotates a blowing fan (not shown) that performs the blowing operation.
At the same time, a worm part 9a is provided at the rearmost part of the rotor shaft 7a.
The worm wheel 10a that meshes with the bearing 13 of the gearbox 12a installed in parallel with the case 5a
A steel ball 16a, which is pressed by a clutch spring 15a, is engaged with a pinion shaft 14a that is pivotally supported at the pinion shaft 14a, and a crank gear 19a that meshes with a gear portion 18a formed at the tip of the pinion shaft 14a is rotatably attached to the crankshaft. The gearbox 12 is connected to the gearbox 12 by 20a.
a, and the boss 21a of the crank gear 19a.
One end of a swinging rod 22a, the other end of which is pivotally connected to a neck piece (not shown), is pivotally connected to the rotor shaft 7a of the motor 6a to rotate the blowing fan and perform the blowing operation. The worm wheel 10 is connected to the rotor shaft 7a of the motor 6a.
a, the pinion shaft 14a, the crank gear 19a, the swinging rod 22a, etc. are driven to cause the head to vibrate.

In the case of conventional electric fans such as those mentioned above, the configuration to create the neck vibration motion of the head of the fan is complex and requires a large number of parts.Also, when press-fitting the pinion bearing and crankshaft into the gearbox, it requires a relatively large size. It requires a hydraulic system, which makes the equipment expensive, makes inspection and maintenance difficult, and has drawbacks such as lubricating oil leaking outside from the gearbox.

Moreover, since the gearbox 12a and the supporting portion 20a of the crankshaft 20a are integrally molded on the case 5a on the rear side, for example, the case 5
a. The gearbox 12a and the support part 20A of the crankshaft 20a must be molded by aluminum die casting, etc., and the parts as a whole are not only heavy but also have a complicated shape, so the mold for molding them is also very expensive. This was one of the causes of an increase in the cost of electric fans.

Furthermore, a portion 20 that supports the crankshaft 20a is provided.
A is the crankshaft 2 with a certain length or more.
If 0a is not maintained, the rod 22a connected to the crank 19a will be eccentric to the crankshaft, and the moment of force will cause the crankshaft 20a to rattle, causing abnormal noises and damage to the crankshaft 20a. There was also a risk that the crankshaft 20a would be irregularly worn and deformed, and that the crankshaft 20a would eventually come off from the holding portion 20A.

Therefore, conventional electric fans are usually designed so that the holding portion 20A of the crankshaft 20a has a length longer than a predetermined length.

As a result, the oscillation mechanism consisting of the crank 19a and the rod 22a connected to the crank 19a is located considerably below the axis of the rotor shaft 7a of the fan motor due to the longer length of the holding portion 20A. As shown in Figures 1 and 2,
The lower part of the crank 19a and the rod 22a protrude from a circle A drawn with the radius being the distance from the axis of the motor to the outermost edge of the cylindrical cases 5a, 6a.

Therefore, the motor cover 2a that surrounds the internal structures such as the fan motor needs to be large enough to cover the crank 19a and rod 22a that protrude from the circle A, and also hide the crank 19a and rod 22a inside. , the head 1a becomes larger accordingly.

In other words, if the crank 19a and the rod 22a are housed within the circle A, the motor cover 2a can be made as small as the size of the circle A, where further miniaturization is impossible in terms of performance. However, in the case of the conventional structure, as mentioned above, there is inevitably a portion that protrudes from the circle A, so the head 1a becomes larger accordingly.

If the fan head is large like this, the stand itself needs to be sized to match the fan head so that the balance with the stand and the design are not compromised. Moreover, it becomes difficult to make the whole electric fan and individual parts compact when packaging and storing them, and to reduce the storage space.This also causes inconveniences in all aspects, such as increasing costs.

<Purpose> In view of the above points, the present invention provides a swing motor separately from the fan motor, and the swing motor and the swing mechanism connected to the swing motor are centered on the axis of the fan motor. so that it is stored within a circle whose radius is the distance to the outermost edge of the fan motor,
The purpose is to make the head more compact by making specific improvements.

<Example> First, the outline of the electric fan will be explained in FIG.
A support post 2 is installed on the top of the support post 2 so that it can be adjusted up and down.
A neck assembly 3 consisting of a neck holder and a neck piece is provided at the end, and the fan head H is supported by the neck assembly 3. The electric fan head H includes a fan 4, a protective net 5, a motor cover 6, and internal structures described below.

Next, the internal structure is shown in Figures 2 to 1.
This will be explained in detail with reference to Figure 0. The internal structure is roughly divided into a fan motor 7, a swing motor 8, a mounting board 9, and a swing mechanism 10.

The fan motor 7 has a front case 11 and a rear case 1.
2. It is composed of a stator 13, a winding assembly 14 consisting of a main winding LM and an auxiliary winding LS, and a rotor assembly 15 having a rotating shaft 16. Above front/back case 1
Reference numerals 1 and 12 are made of pressed steel plates, and ventilation holes 17 and 18 are formed in the end faces, respectively. Also, before
The rear cases 11 and 12 are integrally formed with outwardly projecting flanges 19 and 20 at the edges of their openings, and are connected by abutting the flanges 19 and 20 and fixing them with screws 21. The above flange 19,
At 20, the portions to which the screws 21 are fixed are formed wider than other portions and are provided as tightening tongues 22, 23. Note that the tightening tongues 22 and 23 are each provided at an interval of 120 degrees.

A binding thread 1 is attached to the upper half of the rear surface of the winding assembly 14.
4' fixes the terminal 24.
This terminal 24 has terminal groups separated on the left and right, one terminal group is a relay terminal a, and an auxiliary winding LS.
The other group of terminals consists of terminals d, e, and f, which lead to the respective speed change taps, and a common terminal c, which leads to the main winding LM, and a common terminal c, which leads to the main winding LM. Consists of g. Then,
These left and right terminal groups face the outside of the case 12 through connection holes 25, 25 formed in the case 12, respectively.

The oscillating motor 8 includes a reduction mechanism assembly 26 and the assembly 2.
6 and a motor section 27 integrally mounted on the motor section 6. The speed reduction mechanism assembly 26 is made up of an upper case 29 in which mounting tongues 28, 28 are formed that protrude left and right at the lower opening edge, a cover plate 30 that closes the lower opening of the case 29, and a plurality of gears. The reduction gear group 31 and the last stage gear are fixed and the lid plate 30 is attached.
and an output shaft 32 that extends downward through the output shaft 32. This output shaft 32 is located unevenly from the center of the reduction mechanism assembly 26. Reference numeral 33 designates a bearing for the output shaft 32 that is fixed to the cover plate 30 and projects downward from the lower surface of the cover plate 30. 34 is a shaft of a gear, and one end thereof extends through the cover plate 30 supported by the cover plate 30 and faces outward. On the other hand, the motor section 27 is composed of a reversible synchronous motor, and is integrally fixed onto the upper case 29. The rotating shaft of the motor section 27 is formed by a fixed gear, and is in mesh with the foremost gear of the reduction mechanism assembly 26.

Thus, the fan motor and the swing motor 8 are mounted on a single mounting board 9, which will be described later. The mounting board 9 is formed by drawing into the shape shown in FIGS. 6 to 9, and is attached to the spindle fixing surface 3.
5. Mounting surface 36 of swing motor 8, motor cover 6
It has a projecting piece 37 for attaching the fan motor 7, a support wall 38 for attaching the fan motor 7, and a reinforcing wall 39. The spindle fixing surface 35 is located in the front half of the bottom wall of the mounting board 9, and has a through hole 40 in a portion near its front edge. This through hole 40 has a cylindrical spindle support 4.
1 is inserted and fixed to the mounting board 9 using fixing means such as welding. Further, a spindle 42 is press-fitted into this spindle support 41 via a washer 43 as shown in FIGS. 2 and 3. On the other hand, the mounting surface 36 is located at the rear half of the mounting board 9.
It is one step higher than the spindle fixing surface 35.
That is, the mounting surface 36 is continuous with the rear edge of the spindle fixing surface 35 via the arcuate stepped portion 44, and the height difference between both surfaces 35 and 36 will be described in detail later. Screw holes 45 are formed on both left and right sides of this mounting surface 36, facing the mounting tongues 28, 28 of the oscillating motor 8, and the oscillating motor 8 is mounted using screws 46, 46 that are screwed into these holes. It is fixed on the surface 36. The oscillating motor 8 has a mounting surface 36 attached to the entire circumference of the lower opening edge of the upper case 29.
The output shaft 32 is fixed in such a state that it is in contact with the top and the output shaft 32 is close to the spindle 42 side. Further, the mounting surface 36 of the mounting board 9 has a cylindrical positioning hole 47 and a gear shaft into which the bearing 33 is fitted in a loosely press-fitted or statically fitted state when the oscillating motor 8 is fixed, thereby causing the output shaft 32 to protrude downward. the shaft 34 opposite the lower end of 34;
Seats 48, 48, . The projecting piece 37 is provided upright on the rear edge of the mounting surface 36, and has a screw hole 50 at its upper end into which the mounting screw 49 of the motor cover 6 is screwed.

The support walls 38 are located on both side edges of the spindle fixing surface 35 and protrude obliquely upward. This supporting wall〓〓〓〓〓
A mounting receiving piece 51 extending outward is cut and raised at an intermediate position between the front and back of the mounting member 38, and a through hole 52 is bored in this mounting receiving piece 51. The tightening tongues 22 of the fan motor 7 are abutted against the back surface of the mounting plate 51, and the tightening tongues 22, 23 and the mounting plate are connected using the coupling screws 21 of the front and rear cases 11, 12. Piece 51-3
The fan motor 7 is fixed to the mounting board 9 by tightening the screws. Support walls 3 located before and after the mounting piece 51 in the fixed state of the fan motor 7
Reference numeral 8 supports and receives the fan motor 7 in contact with the outer peripheral surfaces of the front and rear cases 11 and 12 of the fan motor 7. Incidentally, the mounting receiving piece 51 does not protrude outward from the tightening tongue piece 23 when the tongue piece 23 abuts against each other.
The reinforcing wall 39 is located from both side edges to the rear edge of the mounting surface 36, and its front edge is continuous with the support wall 38. That is, the mounting board 9 has a wall formed of the support wall 38 and the reinforcing wall 39 on the outer peripheral edge excluding the front part.

A tongue piece 54 for attaching a starting capacitor 53 of the fan motor 7 is formed at a proper position on one side of the reinforcing wall 39. Further, the mounting board 9 has a reinforcing protrusion 55 formed over the spindle fixing surface 35, the support wall 38, and the stepped portion 44.

The mounting board 9 formed in the above-mentioned shape is mounted within a circle whose radius is the distance R between the center of the rotating shaft 16 and the outermost edge of the fan motor 7 when the fan motor 7 is fixed. The dimensions are set to fit. Further, the arcuate stepped portion 44 is connected to the swing motor 8, the swing mechanism 10, and the starting capacitor 53.
The step size is set such that the distance R falls within a circle drawn with the radius R as the radius.

The swinging mechanism 10 consists of a crank 56 having bosses 57 at unevenly distributed positions, and a swinging rod 59 whose one end is fitted into the boss 57 and rotatably supported by a screw 58.The crank 56 is connected to a swinging motor. It is fixed to the output shaft 32 of No. 8 with a screw 60 or a dowel pin. When the spindle 42 is inserted into the support hole 62 of the neck piece 61, which is a side member of the stand 1, the free end of the swing rod 59 is inserted into the boss portion 63 of the neck piece 61. Incidentally, the spindle 42 becomes the center of rotation of the fan head H when the head vibrates.

In the figure, reference numeral 64 indicates a front cover attached to the front surface of the fan motor 7, and 65 and 66 indicate lead wires and fan stone terminals for interconnecting each electrical component.

Next, the electric circuit will be explained with reference to Figure 11.
Each speed change tap of the fan motor 7 is connected to terminal 2.
4 is connected to the speed adjustment switch 67 through the terminals e, f, and g of the speed adjustment switch 67, respectively.
7 is connected in common with one end of the swing switch 68 to a power supply terminal after a main switch 69 is interposed therebetween. The other end of the oscillation switch 68 is connected to the oscillation motor 8 via the relay terminal a, and then branches, and one end is connected to the capacitor 53.
The other is connected to the auxiliary winding LS via the terminal b, and the other is connected to the terminal g. The main winding LM is branch-connected to a terminal g and a power supply terminal via a common terminal e. The main switch 69 is interlocked with the speed adjustment switch 67, and is closed only when any of the switching pieces of the switch 67 is in the closed state. Speed adjustment switch 6
7 and the oscillation switch 68 are both manual types and are disposed on the stand 1.

Next, the assembly order will be explained. First, the spindle 42 is press-fitted into the spindle support 41 of the mounting board 9 and fixed by caulking or the like. After that, the bearing 33 is inserted into the positioning hole 47 on the mounting surface 36 of the mounting board 9.
The oscillating motor 8 is arranged so that the output shaft 32 protrudes downward from the mounting board 9, and this is screwed into the
6,46. In this fixed state of the oscillating motor 8, the lower end of the gear shaft 34 faces the catch seat 48. At this time, the starting capacitor 53 is also fixed to the tongue piece 54 with a screw. Then, in the next step, the crank 56 is fixed to the output shaft 32 of the oscillating motor 8 with a screw or a dowel pin,
After that, the swing rod 5 is attached to the boss portion 57 of the crank 56.
9 is pivotally supported by screws 58 to complete the swinging device assembly.

On the other hand, the assembly of the fan motor 7 is performed in a separate process from the assembly process of the above-mentioned device assembly, and is assembled by the same operations as general general-purpose motors. Of the screws 21 used to connect the front and rear cases 11 and 12,
Mounting plate 51 of mounting board 9 and tightening tongue pieces 22, 23
Remove the screws 21 that tighten the screws.

Then, the oscillating device assembly and the fan motor 7, which were assembled in separate steps, are combined, that is, the tightening tongues 22 and 23 are brought into contact with the mounting receiving piece 51 of the mounting board 9 from behind, and these 3 are assembled. The fan motor 7 is fixed by tightening the screws 21, and the fan head H
〓〓〓〓〓
Complete the internal structure of. When the fan motor 7 is in the fixed state, the support wall 38 of the mounting board 9 is in the front
Since it contacts and supports the outer peripheral surfaces of the rear cases 11 and 12, when an impact is applied to the fan motor 7 when the fan falls over, the impact force is not concentrated on the mounting plate 51 but on the support wall 8 side. It will be dispersed, and its fixed state will be very strong.

Such an internal structure is supported on the stand 1 side by inserting the spindle 42 into the support hole 62 of the neck piece 61 and simultaneously fitting the oscillating rod 59 into the boss portion 63, and by removing the spindle 42 with a screw. A stop is made. In the case of an electric fan equipped with a double oscillating device, the oscillating rod 59 is fitted into a boss portion provided on a well-known oscillating ring (stand side member).

Finally, connect the fan motor 7, swing motor 8, starting capacitor 53, and each switch 67, 68 on the stand 1 side to the lead wire 65 and the Faston terminal 6.
6 etc., connect at the terminal 24 part and connect the 11th
Form the electric circuit shown in the figure, then motor cover 6,
The front cover 64 etc. are sequentially attached to complete the process.

In such an embodiment, the swing motor 8,
Since the swinging mechanism 10, the mounting board 9, the starting capacitor 53, etc. all fit within a circle drawn with the rotation axis 16 as the center and the distance R as the radius, the maximum diameter of the internal structure is the same as the maximum diameter of the fan motor 7. As a result, the fan head H can be made smaller, and the stand 1 can also be made smaller in consideration of the balance and design with the fan head H, making it possible to downsize the fan as a whole and when packing and storing it. can be made more compact.

That is, once the performance of the fan motor 7 is determined,
Winding assembly 14 and rotor assembly 1 stored inside
The size of the head H is determined, and the cases 11 and 12 are designed to accommodate the assemblies 14 and 15 inside and eliminate the gaps as much as possible to make it as compact as possible. Even if you try to make it more compact, it cannot be made smaller than a circle with radius R that passes through the outermost edge of this case, but the oscillating motor 8, the oscillating mechanism 10, the mounting board 9, the capacitor 3, etc. are housed within the circle. This allows for maximum compactness.

Further, the motor cover 6 may have a simple circular shape with a diameter of 2R. Furthermore, by mounting the spindle 2 and the oscillating motor 8 on a single mounting board 9, the center distance between the center of the spindle 42 and the center of the output shaft 32 of the oscillating motor 8 is constant, and the oscillating mechanism 10 operates smoothly and does not cause any damage. Furthermore, the oscillation motor 8, oscillation mechanism 10, and spindle 42 are assembled in a separate process from that of the fan motor 7, making the work simpler and easier for the operator. The labor burden is also reduced, and assembly work is significantly improved.

On the other hand, the wiring work for the fan head H is done at terminal 2.
You can concentrate on 4 parts, so you can do it efficiently.
Moreover, it is very convenient when bundling the lead wires 65. Further, the part where the lead wires 65 gather is separated from the swinging mechanism 10 side, which is a movable part, by the mounting board 9, so there is no risk that the lead wires 65 will come into contact with the movable part and be damaged. The mounting board 9 is drawn into an arc shape at the stepped portion 44, and the support wall 38 and reinforcing wall 39 are continuously formed by drawing on the outer peripheral edge excluding the front edge, so that extremely strong strength can be obtained. , it is possible to reduce the thickness of the board, which has a great effect on saving material. Furthermore, since the mounting surface 36 of the mounting board 9 approaches the center of the fan motor 7 by forming the stepped portion 44, the length of the protruding piece 37 on the rear edge can be shortened, and the protruding piece 37 has a high strength. , very stable in terms of dimensional accuracy.

<Effects> As described above, the present invention houses a winding assembly consisting of a main winding and an auxiliary winding, and a rotor assembly having a rotating shaft for connecting a fan, and surrounds these two assemblies. It is formed by providing a cylindrical front cover and a rear cover, forming tightening tongues that project outward from the joint surfaces of these front and rear covers, and fastening the tightening tongues together with screws. A oscillating motor that is flat and has a reduction mechanism assembly integrally housed inside and has an output shaft protruding from the bottom side, and this oscillating motor is located on the rear side of the fan motor. The oscillating motor and the fan motor are fixed to a mounting board that supports the oscillating motor and the fan motor from below, and an output shaft of the oscillating motor that penetrates the mounting surface of the mounting board and projects downward, so that the rotation of the output shaft is fixed. A crank that rotates as the engine moves, and a rotary shaft that is rotatably connected to a position eccentric from the center of rotation of the crank.
and a motor cover surrounding the fan motor, the oscillating motor, the mounting board, and the oscillating mechanism so as to store them inside, the fan motor, the oscillating motor, the mounting board and the oscillating mechanism being housed inside. The fastening tongue piece formed on the joint surface of the rear cover is formed to the minimum size necessary for fastening, and the mounting surface of the mounting board that supports the oscillating motor is bent upward at a step. The oscillating motor is placed on the lower side of the mounting surface that supports the oscillating motor within a circle drawn around the rotational axis of the fan motor and with the distance between this rotational axis and the outermost edge of the tightening tongue as a radius. This electric fan is characterized by having a space for storing a mechanism.

Therefore, since a dedicated motor for swinging the head is provided separately from the fan motor and the swinging mechanism is connected to this swinging motor to perform the swinging, the mechanism for swinging the head does not use the conventional fan motor. It's much easier than something that makes you shake your head.

In other words, the only parts required are the fan motor, the swing motor, the mounting board, and the swing mechanism, and the number of parts is reduced compared to the conventional one, and the assembly work is also very simple.

Moreover, the present invention uses a separate mounting board to support the fan motor and the oscillating motor.
The swing motor and the fan motor can be supported more easily than when the swing motor is fixed to the back of the fan motor.

In other words, since the windings etc. are housed inside the case of fan motors, it is impossible to fasten the fan motor with screws etc. protruding inside the fan motor, and methods such as welding also have a thermal effect on the windings. Since it is largely impossible to fix some parts to the fan motor, the fixing support part must be integrally molded into the fan motor case using aluminum die-casting, etc., and as a result, the structure of the case is In addition to being complicated, the weight and size of the fan motor increases, making it inconvenient as an electric fan.

On the other hand, by supporting the fan motor and oscillating motor on the mounting board as described above, the fan motor, oscillating motor, and attached board can be made of thin plates, and the interior of the head is lightweight, compact, and simple. It can be made into a structure.

Moreover, the mounting position of the oscillating motor with respect to the mounting board is on the back side of the fan motor, the mounting surface of the mounting board of this oscillating motor is bent upward with a step, and the lower surface side of the mounting surface is A space for accommodating the oscillating mechanism was formed within a circle drawn with the rotation axis of the fan motor as the center and the distance between this rotation axis and the outermost edge of the tightening tongue as a radius, so that it could be placed inside the head of the fan. The parts of the electric fan are housed within the silhouette of the above circle, making it possible to make it as compact as possible.

In other words, for fan motors, the front and rear cases must be removably fastened for internal maintenance such as repair of broken internal windings.
The best way to fasten the front and rear cases is to provide outwardly projecting tightening tongues on the joining surfaces of the cases, and to fix these tongues together with screws.

On the other hand, for fan motors, the size of the windings (stator, rotor) is determined by performance, and
The windings must be stored as far as they can inside the case so that there are as few gaps as possible inside.

Therefore, the size of the fan motor is formed to the minimum size for performance, and as a result, when the size of the fan motor is set to the minimum size necessary for fastening the tightening tongue, the size of the fan motor is It is impossible to make the motor more compact than the size of a circle drawn with the motor's rotation axis as the center and the distance from this rotation axis to the tightening tongue as a radius, so it is necessary to surround the internal structure with a motor cover as close as possible to this circle. This allows the fan head to be made as compact as possible.

In order to achieve maximum compactness, the present invention bends the mounting surface of the mounting board that supports the oscillating motor upward with a step, and the lower surface of the mounting surface that supports the oscillating motor. By forming a space on the side to accommodate the swing mechanism in a circle whose radius is the distance between the rotation axis of the fan motor and the outermost edge of the tightening tongue, it is possible to It became possible to house the parts, namely the swing motor, mounting board, and swing mechanism, within the silhouette within the circle.

Therefore, by making the head as compact as possible, the entire electric fan can be made compact and lightweight.

[Brief explanation of the drawing]

Figure 1 is an external perspective view, Figure 2 is a sectional view of the fan head, Figure 3 is a half-section front view of the fan head, and Figure 4 is a front view of the fan head.
〓〓〓〓〓
The figure is an explanatory diagram of the internal structure of the fan head, Figure 5 is a rear view showing the winding assembly of the fan motor, Figure 6 is a plan view of the mounting board, Figure 7 is a sectional view of the mounting board, and Figure 8 is a diagram illustrating the internal structure of the fan head.
The figures are a front view of the mounting board, Fig. 9 is a back view of the mounting board, Fig. 10 is a perspective view of the neck piece, Fig. 11 is an electrical circuit diagram, Fig. 12 is a longitudinal sectional view of a conventional electric fan, and Fig. 13. is a cross-sectional view of the conventional electric fan. DESCRIPTION OF SYMBOLS 1...stand, 4...fan, 6...motor cover, 7...fan motor, 8...oscillating motor, 9...mounting board, 10...oscillating mechanism, 16...rotating shaft, 32...
Output shaft, 42... spindle, 44... stepped portion, 56...
Crank, 59... swinging rod. 〓〓〓〓〓

Claims (1)

[Claims] 1. A cylindrical shape that houses a winding assembly consisting of a main winding and an auxiliary winding, and a rotor assembly having a rotating shaft for connecting a fan, and surrounds these two assemblies. A fan motor is formed by providing a front cover and a rear cover, forming tightening tongues projecting outward from the joint surfaces of these front covers, and fastening the tightening tongues together with screws. , a oscillating motor that has a flat shape and has a reduction mechanism assembly integrally housed inside and an output shaft protruding from the bottom side; a mounting board that supports the oscillating motor and the fan motor from below; a crank that is fixed to the output shaft of the oscillating motor that penetrates the mounting surface of the mounting board and projects downward, and that rotates the output shaft; A swinging mechanism consisting of a rod rotatably connected to a position eccentric from the center of rotation of the crank, and a motor cover surrounding the fan motor, swinging motor, mounting board, and swinging mechanism so as to house them inside. and, wherein the fastening tongues formed on the joint surfaces of the front and rear covers of the fan motor are formed to the minimum size necessary for fastening, and a mounting board that supports the oscillating motor. The mounting surface of the fan motor is bent upward with a step, and the rotation axis of the fan motor and the outermost edge of the tightening tongue are placed on the lower surface of the mounting surface that supports the oscillating motor. An electric fan, characterized in that a space for accommodating the oscillating mechanism is formed within a circle drawn with the distance from the oscillating mechanism as a radius.