JPS628720Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an electric fan having a structure in which the head of the electric fan can be raised and lowered.

[Technical field of invention]

Conventionally, in this type of electric fan, in order to hold the fan head at a desired height position, a retaining screw is provided on the support, and the retaining screw is tightened so that its tip is pressed into contact with the support tube. In order to brake the fan head so that it does not drop suddenly when the retainer screw is loosened, a friction body is fitted in pressure contact with the support tube, and the movement of the friction body as the support tube rises and falls is prevented from moving on the support tube side. The configuration is such that a locking portion is provided to suppress the movement.

[Problems with background technology]

However, in such a configuration, the friction body is in pressure contact with the support tube even when raising the fan head, so a lifting force greater than the sum of the weight of the fan head and the frictional force of the friction body must be applied. However, there was a drawback that the lifting operation became extremely difficult.

[Purpose of invention]

Therefore, the purpose of the present invention is to allow the lifting force to be equal to the weight of the fan head when lifting the fan head.
The purpose of the present invention is to provide an electric fan that can lighten the lifting operation.

[Summary of the idea]

The present invention includes a friction body formed in a substantially annular shape with expansible ends and constantly biased in the direction of diameter reduction and fitted in pressure contact with the support tube, and a friction body provided on the support tube side to prevent the rise and fall of the support tube. upper and lower locking portions for suppressing vertical movement of the friction body; and upper and lower locking portions formed on at least one of the friction body and the upper locking portion so that the friction body comes into contact with the other as the support tube rises. By providing a sloped portion that expands the diameter, the degree of pressure contact of the friction body to the support pipe when the support pipe is raised is minimized, so that the friction body does not exert a large frictional force on the support pipe when the support pipe is raised. It is characterized by the fact that it

[Example of idea]

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

First, in FIG. 1, 1 is a base having a support 2, 3 is a support tube provided on the support 2 so that it can rise and fall, and 4 is a fan head attached to the upper end of the support tube 3. This is provided with a blower blade 5 that is rotatably driven by a motor (not shown) and a guard 6 that covers the blower blade 5. Next, in FIGS. 2 and 3 showing the detailed structure inside the support column 2, 7
8 is a cap fitted onto the open upper end of the support column 2;
Reference numeral denotes a locking plate serving as a lower locking portion, and this locking plate 8 has an insertion hole 8a in the center through which the support tube 3 is inserted, and is fixed within the support portion 2 by, for example, spot welding. 9 is a brake plate whose lower end is supported by a locking plate 8; 10 is a retaining screw; The tip portion can be brought into contact with the brake plate 9. Then, by threading the retaining screw 10, the brake plate 9 is pressed and brought into pressure contact with the outer circumferential part of the support tube 3.
The support tube 3 is unfixed by fixing the fan head 4 at a desired height position, and unscrewing the retaining screw 10 to loosen the pressure of the brake plate 9 against the support tube 3. , so that the height of the fan head 4 can be adjusted by moving it up and down. Reference numeral 11 denotes a friction body, which is, for example, a combination of two roughly anticircular divided friction bodies 12, 12, and an open part facing each other and spaced apart between one end of the two divided friction bodies 12, 12. 11a and is formed into a substantially annular shape with ends. And this friction body 11
is located between the cap 7 and the locking plate 8 of the strut portion 2, and is fitted into the outer circumference of the support tube 3, and has an end in a V-shaped groove 12a formed on the outer circumference of each divided friction body 12. A spring 13 is fitted to urge the entire friction body 11 in the diametrical direction, so that the friction body 11 is always in pressure contact with the support tube 3. Reference numeral 14 denotes a slope portion formed at one end of each divided friction body 12, which allows the open portion 11a of the friction body 11 to expand upward. Reference numeral 15 designates a rotation preventing protrusion protruding from the other end of each divided friction body 12. Reference numeral 16 denotes a forked holding piece that projects downward from the cap 7, into which the anti-rotation protrusions 15, 15 of each divided friction body 12 are fitted so as to be movable up and down. , 12 are prevented from rotating freely relative to the support tube 3, so that the position of the open portion 11a and the size of the gap therebetween are prevented from becoming small. Reference numeral 17 designates a plate-shaped upper locking portion that also protrudes downward from the cap 7. This is provided corresponding to the open portion 11a of the friction body 11, and has sloped portions 18 on both sides of the lower end that become narrower toward the bottom. When the friction body 11 rises as the support tube 3 rises, the slope portion 14 of the friction body 11 comes into contact with the slope portion 18 of the upper locking portion 17.

Next, the operation of the above-mentioned configuration will be described.
When the press screw 10 is turned and screwed back, the pressure contact force of the tip of the press screw 10 against the brake plate 9 is loosened, so that the support tube 3 can be moved. Then, a downward force acts on the support tube 3 and, by extension, on the friction body 11 fitted to the support tube 3 due to the weight of the fan head 4, but since the friction body 11 is restrained from moving downward by the locking plate 8, the support tube 3 is braked by the friction body 11, and this makes it possible to prevent the fan head 4 from suddenly descending due to its own weight. After this, the fan head 4 can be set to a desired height position as follows. First, for example, when lowering the fan head 4, the fan head 4 is pressed down against the frictional force of the friction body 11, and at that position the press screw 10 is turned and screwed forward to fix the support tube 3. When raising the fan head 4, the fan head 4 is raised to a desired height position against its own weight. At this time, the friction body 11 also rises with the rise of the support tube 3, so that the lower end of the upper engaging portion 17 is relatively closer to the friction body 11.
1, and the inclined surface 14 of the friction body 11 is inserted into the open portion 11a of the upper engagement portion 17.
As a result, the friction body 11 expands in diameter against the elastic force of the ring-shaped spring 13 due to the so-called wedge effect, so that the frictional force that the friction body 11 exerts on the support tube 3 becomes extremely small, and the force required to lift the fan head 4 is only that required to resist its own weight. After the fan head 4 has been raised to the desired height in this manner,
The press screw 10 is turned and screwed forward to fix the support tube 3 in place.

In addition, in this embodiment, the friction body 11 and the upper locking part 1
Although the slope portions 14 and 18 are formed on both sides of the cover 7, the present invention is not limited thereto, and the slope portion may be formed on only one of the two sides.

[Effect of idea]

As described above, the present invention includes a friction body formed in a substantially annular shape with expandable and contractible ends, which is constantly biased in a diametrically contracting direction and fitted in pressure contact with the support tube, and a friction body provided on the support tube side and attached to the support tube. upper and lower locking portions for suppressing the vertical movement of the friction body as the support tube rises and lowers; The feature is that the friction body is provided with a slope portion that expands the diameter of the friction body, and as a result, the friction body can prevent the support pipe from rapidly descending due to the weight of the fan head, and when the support pipe rises, By enlarging the diameter of the friction body, it is possible to prevent the friction body from exerting a large frictional force on the support tube, so when lifting the fan head, only a pulling force equivalent to the weight of the fan head is required, making the lifting operation easier. This has the effect of making it lighter.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is an overall side view, FIG. 2 is an enlarged vertical sectional view of the main part, and FIG. 3 is an exploded perspective view. In the figure, 1 is the base, 2 is the support section, 3 is the support tube, 4
1 is a fan head, 8 is a locking plate (lower locking portion), 11 is a friction body, 13 is a ring-shaped spring, 14 and 18 are slope portions, and 17 is an upper locking portion.

Claims (1)

[Scope of utility model registration request] A support tube with a fan head attached to the upper end is inserted through a support provided on a base so that it can rise and fall. a friction body fitted in pressure contact with the support tube; upper and lower locking portions provided on the support tube side to suppress vertical movement of the friction body as the support tube rises and falls; An electric fan comprising: a slope portion formed on at least one of the friction body and the upper locking portion so as to contact the other and expand the diameter of the friction body as the support tube rises.