JP7714218B2 - Clothing fan and clothing equipped with the same - Google Patents

Description

The present invention relates to a clothing fan that is attached to clothing such as work clothes and blows outside air into the clothing.

A clothing fan is a blower attached to the back of clothing, etc., and reduces sweating by sending outside air into the clothing as the fan rotates. The clothing fan is equipped with an axial flow motor fan arranged coaxially with the motor, and the motor fan is housed in a cylindrical body (casing). The fan is attached to the clothing by clamping the edge of a mounting hole formed in the clothing into the body (see, for example, Patent Document 1).

Utility Model Registration No. 3213564

Clothing fans are usually attached to the back of clothing near the sides, making it impossible to ensure a sufficient distance between the body and the clothing fan. As a result, depending on the posture of the wearer while working, the clothing fan is likely to come into contact with the body. Furthermore, when sitting in a chair or in a work area with limited space, the clothing fan may come into contact with equipment, etc., and cause a malfunction.

Therefore, there is a need to provide a clothing fan that effectively blows air without interfering with the wearer's clothing.

The clothing fan of the present invention is a fan that can be attached to clothing and includes a cylindrical casing with an inlet and an outlet, and a propeller fan housed in the casing. In a propeller fan with multiple blades attached to a cylindrical hub, eight blades are attached to the side of the cylindrical hub at equal or irregular intervals along the circumferential direction. For example, it is possible to attach eight blades at equal intervals to the side of the hub. For example, if the inlet and outlet of the casing have a ribbed structure with multiple concentric annular ribs and multiple radial ribs that intersect with the annular ribs, and the annular portion (ring) is attached to clothing by screwing, the axial length of the side of the hub can be less than the axial length of the annular portion located between the inlet and outlet.

Each blade is attached with an axial width corresponding to the axial length of the side of the hub. Here, "with an axial width corresponding to the axial length of the side of the hub" means that the blade has a chord length that extends to both ends of the side of the hub or near both ends. "Axial width corresponding to the axial length of the side of the hub" does not only mean that the length is strictly the same, but also includes having an axial width that corresponds to the width from near the leading edge of the side of the hub to near the bottom end. In other words, it means that the leading and trailing ends of each blade have a chord length that extends to both ends of the hub widthwise or near both ends.

In this invention, when multiple (eight) blades are arranged on the development surface as a blade row, the spacing between adjacent blades is greater than the chord length of the blade. A propeller fan consisting of eight blades not only achieves a thinner fan, but also reduces weight, reduces the load during rotation, and enables effective airflow at both low and high rotational speeds.

The three-dimensional shape of each blade can be variously curved. Each blade can be formed so that the leading and trailing edges of the three-dimensional airfoil follow a plane perpendicular to the axial direction of the hub. Furthermore, each blade can be attached at an angle of 45 degrees or less relative to the tip surface perpendicular to the hub axis. For example, they can be attached at an angle between 35 and 45 degrees. It is also possible to adjust the solidity ratio to adjust the degree of packing of the eight blades. For example, the blade shape and attachment angle can be configured so that the projection size of the gap between adjacent blades onto a plane perpendicular to the hub axis is smaller than half the projection size of the blade onto a plane perpendicular to the hub axis.

This invention provides a clothing fan that effectively blows air without interfering with clothing.

1 is a perspective view of a clothing fan according to a first embodiment, seen from the inlet side. FIG. FIG. 2 is an exploded perspective view of the clothes fan as seen from the outlet side. FIG. 2 is a side view of the clothing fan. FIG. FIG. 2 is a perspective view of the propeller fan as seen from the outlet side. FIG. 2 is an exploded perspective view of the propeller fan and the motor housing as viewed from the intake port side. FIG. FIG. 4 is an enlarged partial view of FIG. 3 showing the contact portion between the ring and the flange. FIG. 10 is a front view of a clothing fan according to a second embodiment. FIG. 10 is a front view of a propeller fan according to a second embodiment. FIG. 10 is a perspective view of a propeller fan according to a second embodiment, as viewed from the rear side. FIG. 10 is a partial perspective view of a clothing fan according to a third embodiment, as viewed from the rear side. FIG. 10 is a partial perspective view of a clothing fan according to a fourth embodiment, seen from the rear side.

The clothing fan of this embodiment will now be described with reference to the drawings. Figure 1 is a perspective view of the clothing fan of the first embodiment, seen from the inlet side. Figure 2 is an exploded perspective view of the clothing fan, seen from the outlet side. Figure 3 is a side view of the clothing fan. The overall configuration of the clothing fan will be described using Figures 1 to 3.

The clothing fan 10 is a small air blowing device that can be attached to dedicated clothing 100 (see Figure 2) and is detachably attached to a mounting hole 100R formed on the back side of the clothing 100. The clothing fan 10 comprises a propeller-shaped axial flow fan (hereinafter referred to as a propeller fan) 20 and a cylindrical casing 30 that houses the propeller fan 20, and is attached so that the intake port 10I is on the outside of the clothing and the exhaust port 10F (see Figure 2) is on the inside of the clothing.

The casing 30 is composed of a main body 32 and a motor mounting portion 34. As shown in Figure 2, the motor mounting portion 34 is removably mounted to the main body 32 by an engagement portion 34T. The main body 32 has an annular portion 36 that forms a flange 32F at the end on the intake port 10I side, and the annular portion 36 houses the propeller fan 20. For ease of explanation, the motor is not shown in Figure 2.

The intake port 10I of the main body 32 is an opening with a ribbed structure, with the flange 32F as the outer frame. Multiple radial ribs 32R1 extend radially from the cylindrical center 31, and two annular ribs 32R2 are arranged concentrically, intersecting the radial ribs 32R1.

The motor mounting section 34 has a cylindrical motor housing 50 with a bottom in its center, and a ribbed structure that forms a dish-shaped frame, functioning as the discharge port 10F (see Figure 3). The motor housing 50 houses a motor (not shown), such as a brushless motor, in its internal space 54B. The ribbed structure of the motor mounting section 34 is configured so that multiple radial ribs 34R1 intersect with concentric annular ribs 34R2, connecting them to the annular frame 35. The lid 60 has an engagement piece 60T that can be inserted into an engagement hole 54K in the motor housing 50, and closes the motor housing 50.

A radially protruding connection portion 55 is formed near the opening of the motor housing 50. A power cable (neither shown) for connecting to a battery is connected to an input terminal 54M provided at the connection port 55 of the motor housing 50. The propeller fan 20 is attached to the output shaft of a motor arranged coaxially in the casing 30, and rotates when driven by the motor. The clothes fan 10 can be connected to a battery with a variable output voltage, allowing the output voltage to be adjusted in four stages, for example. The propeller fan 20 sends an air volume corresponding to the output voltage toward the outlet 10F.

The ring 40 is a holding member that holds the garment 100 (the periphery of the mounting hole 100R) between itself and the flange 32F of the main body 32, and is threadedly engaged with the annular portion 36 of the main body 32 (see Figure 2). The ring 40 rotates along the male threads 36M formed on the outer periphery of the annular portion 36 until the flange 40F formed on the outlet-side end of the ring 40 comes into contact with the flange 32F of the main body 32. Here, the side of the ring 40 is formed with irregularities, but it may also be cylindrical without any irregularities.

With the ring 40 removed, the user inserts the casing 30 into the mounting hole 100R of the clothing 100 from the motor mounting portion 34 side. Then, the user rotates the ring 40 around the casing 30 from the inside of the clothing to tighten it. This attaches and secures the clothing fan 10 to the clothing 100. The side surface 32S of the flange 32F of the main body 32 has a smooth wave-like shape that makes it easy to grip the flange 32F at a glance, and does not have any protrusions or edges that could catch fingers. The flange 32F can also be shaped in a way other than a wave-like shape, such as a circular shape.

The clothing fan 10 of this embodiment is a thin fan with a narrow width along the fan axis E (see Figure 3), achieved by the configuration of the propeller fan 20. The motor housing 50 is also designed to prevent the motor from overheating, even when the battery output voltage is increased. Furthermore, when the ring 40 is tightened around the casing 30, it is designed to restrict rotation in the direction that would loosen the ring 40. These features are described in detail below.

First, the configuration of the propeller fan 20 will be described using Figures 4 and 5. Figure 4 is a plan view of the propeller fan 20 as seen from the intake port 10I side (front side). Figure 5 is a perspective view of the propeller fan 20 as seen from the exhaust port 10F side. The axial flow propeller fan 20 is an impeller with eight blades (hereinafter also referred to as vanes, as necessary) 20A-20H attached to a cylindrical hub 21, and a cylindrical protrusion 21T1 is formed in the center of the tip surface 21T2 of the hub 21. The central axis of the hub 21 coincides with the axis E of the casing 30 (the motor axis) (hereinafter the hub axis will also be referred to as E).

The clothing fan 10 is a single-stage axial fan with the intake port 10I facing forward. Air is sent from the intake port 10I to the outlet port 10F (rear side) as the hub 21 attached to the motor's output shaft rotates. The blade profile, including the shape and mounting angle of the blades 20A-20H, is designed to create this flow. The propeller fan 20 rotates clockwise when viewed from the outlet port 10F (rear side).

The three-dimensional blade shape and mounting angle θ of all eight blades 20A-20H are the same here. The mounting angle θ is defined as the angle of inclination relative to the tip surface 21T2 (see Figure 4), which is perpendicular to the axis E of the hub 21. For example, in the case of blade 20B, it is expressed as the angle of inclination relative to the tip surface 21T2 of the line connecting the leading edge K2 and trailing edge K1 of the blade at the base relative to the side surface 21S of the hub 21. The mounting angle θ here is defined to be 45° or less. For example, the mounting angle θ is defined to be in the range of 35° to 45°.

In this embodiment, eight blades 20A-20H are attached to the side surface 21S of the hub 21 at equal intervals along the circumferential direction. That is, adjacent blades are positioned at an angle α of 45° from the center. The angle α is an angle defined by a plane perpendicular to the axis E of the hub 21. For example, the angle α between the leading edge portions K3, K5 and the trailing edge portions K4, K6, which correspond to the outermost (furthest outward) blade edges of blades 20A, 20B, is all 45° when taken as the reference plane perpendicular to the axis E of the hub 21.

The eight blades 20A-20H are attached with a length (chord length) that extends across the entire axial direction of the side surface 21S of the hub 21 (hereinafter referred to as the hub side surface). That is, the axial width I of each blade 20A-20H at the hub side surface 21S corresponds to the axial length L of the hub side surface 21S. For example, in the case of blade 20B, the trailing edge K1 of the attachment portion (root) is located near the lower end 21P of the hub 21, and the leading edge K2 is located near the edge 21N of the tip surface 21T2 of the hub 21.

Furthermore, for the eight blades 20A-20H, the leading edge from the attachment point (root) along the side of the hub 21 to the radially furthest end (in the case of blade 20B, the blade edge extending from leading edge K2 to trailing edge K4) lies along a plane perpendicular to the axis E of the hub 21. The same is true for the trailing edge (in the case of blade 20B, the blade edge extending from leading edge K1 to trailing edge K3). Therefore, each blade, as a three-dimensional blade, is formed so that its leading edge and trailing edge lie along planes that are parallel to each other. Furthermore, each blade has a blade shape with edges at the leading and trailing edges (see K3 and K4 in the case of blade 20B).

On the other hand, when the three-dimensional blade shapes of blades 20A-20H are viewed radially, the blade edges near the leading edge 21N of hub 21 (blade edges K4-K3 in the case of blade 20B) are more curved than the blade edges near the lower end 21P of hub 21 (blade edges K2-K1 in the case of blade 20B), and the curved shape becomes more twisted the closer it is to the leading edge 21N of hub 21. Therefore, the chord length of the blade edge farthest outward in the radial direction (corresponding to the length of the straight line connecting K3 and K4 in the case of blade 20B) is longer than the blade chord length near the attachment part (root) to hub 21 (corresponding to the length of the straight line connecting K1 and K2 in the case of blade 20B).

Furthermore, blades 20A-20H have a twisted airfoil shape on the tip surface 21T2 side of the hub 21, so that the inclination angle of the line connecting the leading and trailing edges of the radially outermost blade edge relative to tip surface 21T2 perpendicular to the hub axis E (in the case of blade 20B, the inclination angle of the line connecting K3 and K4) is smaller than the inclination angle of the mounting portion (in the case of blade 20B, the inclination angle of the line connecting K2 and K1 relative to tip surface 21T2 perpendicular to the hub axis E).

Due to the curved surface shape of blades 20A-20H, a space is maintained between adjacent blades (see Figure 4). For example, if a straight line extending from leading edge K4 of blade 20B along axis E is defined, that straight line will not overlap with the adjacent blade 20A.

When blades 20A-20H are deployed on a plane as a cascade, spacing s, which represents the distance between adjacent blades, is greater than chord length l. Furthermore, the stagger angle ξ, which represents the inclination of the blades when deployed as a cascade, i.e., the blade inclination angle relative to axis E, has an absolute value greater than 45 degrees because, as mentioned above, the installation angle θ is 45 degrees or less. However, if the inclination angle from the cascade direction is expressed as the stagger angle, the installation angle will be the same. Since spacing and chord length are common knowledge to those skilled in the art, an expanded diagram of the cascade has been omitted here.

For example, in the case of adjacent blades 20A and 20B, the spacing s, which is the distance between the trailing ends of the outermost blade edges (equivalent to the distance between K5 and K3 in the circumferential direction in the case of blades 20A and 20B), is greater than the chord length l (the straight line connecting K6 and K5 of blade 20A, or the straight line connecting K4 and K3 of blade 20B) (s>l).

On the other hand, the ratio of spacing s to chord length l, i.e., the solidity σ (= l/s), is set so that adjacent blades do not become too close together. As shown in Figure 4, the projected size of the gap between adjacent blades when viewed from the direction of axis E, i.e., the size of the area when projected onto a plane perpendicular to the axis E of the hub 21, is set to be smaller than the projected size of each blade, but greater than half.

Thus, even though the fan has eight blades, the blade shape ensures an appropriate amount of space between adjacent blades when viewed from the hub axis direction. As explained below, this makes it possible to achieve a thin, quiet garment fan 10 and stable airflow function when the fan is operating.

Conventionally, an even number of blades was thought to be more likely to cause resonance and lead to adverse effects such as noise, so electric fans, automobile radiator cooling fans, and small computer cooling fans usually have an odd number of blades (three, five, or seven in the case of electric fans). In other words, the blades are attached at positions offset from the positions where they face each other.

However, in workplaces and event venues where the clothing fan 10 is used, a certain amount of noise and static is inevitable, and the impact of the number of blades on noise is relatively small. Rather, in the case of the clothing fan 10, the wind noise caused by the rib structure formed on the intake 10I and exhaust 10F of the casing 30 has a significant impact on noise. This rib structure is necessary for reasons such as maintaining the strength of the casing 30 and preventing contact between the propeller fan 20 and external devices.

However, unlike computer cooling fans or automobile cooling fans, the clothing fan 10 does not stay in the same place while driving, and its position and posture change significantly depending on the movement of the wearer. In this case, an even number of propeller fans 20 with blades positioned in opposing positions have not only rotational symmetry but also line symmetry, which improves center of gravity balance and makes the blades more resistant to posture changes and forces. Furthermore, when adjusting the output voltage in stages using a battery, the presence of blades in opposing positions makes it easy to instantaneously increase the rotation speed of the propeller fan 20.

On the other hand, when using an even number of blades, if you want to obtain the required airflow with a reduced number of blades, you need to attach the blades to the hub 21 as flat as possible (aligned with the hub tip surface 21T2) and increase the blade width. However, if you make the mounting angle θ as small as possible and use blades with a wide blade width, the force applied to the base of the blade increases, and from the perspective of hub strength, you need to ensure that the axial length of the hub side is sufficient. Increasing the axial length of the hub makes it impossible to achieve a thin fan.

In a single propeller fan 20 consisting of eight relatively large blades 20A-20H, the force applied to each of the blades 20A-20H is smaller than when there are fewer blades. Furthermore, when the eight blades 20A-20H are deployed in a cascade, the relationship between the spacing s and the chord length l is such that the spacing s is secured by sufficiently reducing the axial length L of the side surface 21S of the hub 21, while the solidity σ is greater than 1/2. By ensuring sufficient blade area while not tilting each blade too far, excessive force is not applied to the blade roots.

For this reason, even when blades 20A-20H are configured with an axial width I that corresponds to the axial length L of side surface 21S of hub 21, sufficient strength of the hub 21 is ensured. As a result, the axial length L of side surface 21S of hub 21 can be made shorter than the axial length W of annular portion 36 of casing 30 (see Figure 3), meaning that the rotation area of blades 20A-20H can be contained within annular portion 36. This leads to a shorter (thinner) axial width of the clothes fan 10.

Even if the eight blades 20A-20H are spaced relatively far apart and the mounting angle θ is relatively large (the blades are not tilted very far), the clothing fan 10 attached to the garment 100 is positioned close to the body, so there is no need to blow air far along the fan axis like an electric fan; instead, it is preferable to blow air in the direction that flows around it.

By fitting the height of the propeller fan 20 within the annular portion 36 of the casing 30, air flowing near the radially outermost blade edge (for blade 20B, blade edges K3 to K4) is influenced by the blade portion with the fastest rotational speed and is discharged from near the frame 35 of the motor mounting portion 34, which has a ribbed structure. As a result, an effective flow can be created inside the clothing.

In particular, each three-dimensional blade is formed so that its leading edge and trailing edge are parallel to each other, which prevents an increase in three-dimensional turbulence as air passes through the gaps between the blades. Furthermore, the entire trailing edge of the blade forms the blade portion with a high rotational speed, creating a more effective flow. Meanwhile, the mounting angle θ of the eight blades 20A-20H is relatively large, and the blade span is kept small, which helps to reduce noise from each blade.

Furthermore, when the propeller fan 20 is configured with eight blades 20A-20H, when the output voltage is set low and the rotation speed becomes slow, negative pressure is maintained on the intake port 10I side compared to the outlet port 10F side. Therefore, at the same rotation speed, air can be blown more efficiently than a propeller fan with fewer blades.

When configuring the blades with more than eight blades, it is possible to configure them with 10 or 12 blades from the perspective of specific speed (type number). However, this makes it difficult to ensure spacing s during blade row expansion, and the force acting on the blades increases, making them unsuitable for high-speed rotation, so a configuration with eight blades 20A-20H is more appropriate. Note that, as long as linear symmetry is acceptable, an even number of blades may be attached to the hub at uneven intervals. Taking into consideration ensuring spacing, it is possible to attach eight blades at uneven intervals with linear symmetry. For clothing fans, in addition to a screwdriver-type attachment structure using the ring 40, attachment structures using locking or fitting are also possible.

Next, using Figures 2 and 6, we will explain the structure of the motor housing 50, which prevents the motor from overheating. The motor housing 50 is composed of a cylindrical portion 52 having a tip surface 52K and a skirt portion 54 extending from the lower end of the cylindrical portion 52. A hole is formed in the tip surface 52K through which the output shaft of the motor 70 passes, and the motor 70 is fixed within the motor housing 50 at a position where it contacts the back surface 52B (see Figure 2) of the tip surface 52K.

The hub 21 of the propeller fan 20 is sized to accommodate the cylindrical portion 52 of the motor housing 50, and the cylindrical portion 52 is covered (surrounded) by the hub 21. At this time, the position of the lower end 21P of the hub 21 exceeds the position of the opening 52M along the housing axial direction (see dashed line L' in Figure 6). A gap is formed between the inner surface 21M of the hub 21 (see Figure 5) and the side surface 52S of the cylindrical portion 52.

The cylindrical portion 52 has multiple openings 52M formed along the axial direction from the edge of the tip surface 52K. Here, six rectangular openings 52M are formed at equal intervals around the circumference of the housing. Furthermore, four of the six openings 52M are formed at positions axially away from the engagement hole 54K with the lid 60.

By forming this opening 52M, it is possible to prevent the motor 70 from overheating. That is, while the motor 70 is rotating, the temperature of the motor 70 rises, particularly at the tip of the motor 70 near the hub 21. This becomes more pronounced when the battery output voltage is increased. However, the heat from the motor 70 is released through the opening 52M into the gap between the motor housing 50 and the hub 21, thereby preventing the temperature of the motor 70 from rising.

In other words, the air heated near the tip of the motor 70 in the motor housing 50 is so hot that it flows out through the opening 52M and easily escapes to the outside through the gap between the motor housing 50 and the hub 21. This flow creates an airflow in which relatively cool air flows into the motor housing 50. In addition, by providing the engagement hole 54K at a position away from the opening 52M along the housing axial direction, an airflow in which heated air flows out through the gap between the motor housing 50 and the hub 21 is more easily created.

The primary function of the clothing fan 10 is to reduce sweating by blowing air, and it is undesirable for air warmed by heat dissipation from the motor 70 to be blown into the clothing 100. However, because the opening 52M is covered by the hub 21, the air flowing out from the gap between the hub 21 and the motor housing 50 flows toward the outlet 10F along the surface of the skirt portion 54.

The blades 20A-20H of the propeller fan 20 rotate at a faster speed toward the blade tips, and the airflow of the clothing fan 10 is greatly affected by the air flowing near the blade tips. This prevents the heat released along the motor housing 50 from directly affecting the air sent into the clothing 100.

The shape, position, and other configurations of the openings 52M are not limited to those described above. It is also possible to form openings that extend radially along the housing, or to form openings at uneven pitches. Furthermore, openings may be formed from the side surface 52S to the tip surface 52K of the cylindrical portion 52 of the motor housing 50, or an independent opening may be formed only on the tip surface 52K. Alternatively, the hub 21 may partially cover the opening (the symbol L' in Figure 6 is located partway through the opening 52M), or an opening may be formed away from the edge of the tip surface 52K toward the discharge port 10F along the housing axial direction.

Next, using Figures 2, 7, and 8, we will explain how to attach the ring 40 to the clothing fan 10 by screwing it in. A female thread 40M is formed on the inner surface of the ring 40 (see Figure 7), and the ring 40 can be screwed in until it contacts the flange 32F of the main body 32. Furthermore, the contact surfaces of the ring 40 and the flange 32F are formed with complementary profiles along the circumferential direction that restrict rotation of the ring 40 in the loosening direction.

Figures 2, 7, and 8 show an example of such a profile, in which convex portions are formed on each other's surfaces. As shown in Figure 7, a plurality of convex portions 42 are formed at predetermined intervals (here, 30 evenly spaced convex portions) around the entire circumferential direction on the bottom surface 42P of the ring 40 (hereinafter referred to as the flange-facing surface). Meanwhile, a plurality of convex portions are also formed at predetermined intervals along the circumferential direction on the top surface 32P of the flange 32F of the main body 32 (hereinafter referred to as the ring-facing surface). Here, four convex portions 33 are formed at equal intervals (two are shown in Figure 2, and one in Figure 8).

The protrusion 42 formed on the flange-facing surface 42P of the ring 40 has a cross-sectional shape that is smoothly curved in the circumferential direction, with no edges formed on its surface. Meanwhile, the protrusion 33 formed on the ring-facing surface 32P of the main body 32 has a trapezoidal cross-sectional shape with edges formed. The height of the protrusion 42 from the flange-facing surface 42P is approximately equal to the height of the protrusion 33 from the ring-facing surface 32P.

Figure 8 shows the contact state between the protrusions 42 and 33 when the ring 40 is in the tightest position (a position where the ring 40 cannot turn any further in relation to the female thread 40M and male thread 36; hereafter referred to as the maximum tightening position) without the garment 100 clamped. The circumferential distance between the protrusions 42 formed on the flange-facing surface 42P of the ring 40 is longer than the circumferential width of the protrusions 33 formed on the main body portion 32 (flange 32F). When the ring 40 is in the maximum tightening position, each protrusion 33 is sandwiched between adjacent protrusions 42 on either side of it.

As the ring 40 is rotated to the maximum tightening position, the flange-facing surface 42P of the ring 40 gradually approaches the ring-facing surface 32P of the main body 32. Before reaching the maximum tightening position, some of the protrusions 33 on the ring-facing surface 32P of the main body 32 come into contact with the protrusions 42 on the flange-facing surface 42P of the ring 40, and the ring 40 rotates with resistance to the final maximum tightening position.

Incidentally, the ring 40 is actually tightened with the garment 100 sandwiched between the ring 40 and the flange 32F. If the fabric of the garment 100 is very thin, the ring 40 can be turned to the maximum tightening position with almost no effect from the fabric. Therefore, once the ring 40 is rotated to the maximum tightening position, the protrusion 42 encounters resistance when it tries to get over the protrusion 33, restricting rotation of the ring 40 in the loosening direction.

In addition, even if the fabric of the garment 100 is relatively thick, the convex portions 42 and 33 have complementary shapes that sandwich the garment 100 and provide resistance to each other before the ring 40 reaches the maximum tightening position, so rotation of the ring 40 in the loosening direction can be prevented even near the maximum tightening position.

Furthermore, frictional resistance increases as the clothing sandwiched between protrusions 42 and 33 undulates, making it possible to prevent rotation of ring 40 in the loosening direction even before protrusions 42 and 33 sandwich clothing 100 between them and encounter resistance from each other.

On the other hand, when the protrusions 33 of the flange 32F are interposed between adjacent protrusions 42 of the ring 40, there is a slight gap between the protrusions 33 and the protrusions 42 on either side of it. This gap allows for slight rotation of the ring 40, and by applying momentum when rotating the ring 40 in the loosening direction, the user can make the protrusions 33 overcome the protrusions 42 and loosen the ring 40. Note that the shapes of the protrusions 33 and 42 can also be other than those described above, as long as they have a height and cross-sectional shape that allows them to apply force to each other, sandwiching the garment 100 when twisting the ring 40, and rotate the ring 40 to the maximum tightening position or a position nearby.

As explained above, by forming complementary profiles in which contact between the protrusions 42 and 33 acts as a means for restricting rotation in the loosening direction of the ring 40, the clothing fan 10 can be securely attached to the clothing 100. Furthermore, by forming multiple protrusions 42 at relatively short intervals on the flange-facing surface 42P and making the circumferential width of the protrusions 33 shorter than this interval, the gap between the flange-facing surface 42P and the ring-facing surface 32P becomes approximately equal along the entire circumference, making it easier to clamp the fabric of the clothing 100 with uniform force along the entire circumference.

The number of convex portions 42 and convex portions 33 can be set to numbers other than those mentioned above (for example, convex portions 33 in the range of 20 to 40, and convex portions 42 in the range of 2 to 10). Convex portions 33 may also be formed on the ring-facing surface 32P, and convex portions 42 may be formed on the flange-facing surface 32P, as long as the number of convex portions on one side is greater than the number of convex portions on the other side. Furthermore, the complementary profiles are not limited to a configuration in which convex portions are formed on each other, and may also be a configuration of concave and convex portions.

Next, we will explain the second embodiment of a clothes fan using Figures 9 to 11. In the second embodiment, the area of each blade is larger than in the first embodiment, and the blades are configured to be more tightly packed.

Figure 9 is a front view of the clothes fan of the second embodiment. Like the first embodiment, the clothes fan 10' has a ribbed structure on its front side consisting of radially extending ribs 32'R1 and annular ribs 32'R2, but the spacing between adjacent ribs 32'R1 is wider than in the first embodiment.

Figure 10 is a front view of a propeller fan according to a second embodiment. Figure 11 is a perspective view of a propeller fan according to a second embodiment, viewed from the rear.

The propeller fan 20' has eight blades 20'A-20'H, and as in the first embodiment, each blade is attached at a predetermined attachment angle θ so that it has a length (chord length) spanning the entire width direction length L of the side surface 21'S of the hub 21'. The attachment angle θ here is smaller than in the first embodiment.

Furthermore, the blade curved shape is such that the length of the radially outermost blade edge (corresponding to the length of the straight line connecting K3 and K4 in the case of blade 20'B) is longer than that in the first embodiment, relative to the length near the attachment portion (base) to hub 21' (corresponding to the length of the straight line connecting K1 and K2 in the case of blade 20'B). As a result, the blade area of each blade is larger than that in the first embodiment.

When eight blades 20'A-20'H are deployed as a cascade, the spacing s is greater than the chord length l (s > l), as in the first embodiment. On the other hand, the stagger angle ξ is larger compared to the first embodiment because the mounting angle θ is smaller, as described above.

As a result, the spacing between adjacent blades is narrower than in the first embodiment, while still maintaining a certain degree of spacing s. As is clear from a comparison of Figures 4 and 10, the projected size of the gap between adjacent blades when projected onto a plane perpendicular to the axis E of the hub 21 is smaller than the projected size of each blade, in this case less than half.

This configuration of the propeller fan 20' makes it possible to increase the airflow volume while maintaining the propeller fan's axial thinness. Meanwhile, by configuring it with eight blades, the surface area of each blade does not increase significantly, even though each blade is installed in a relatively horizontal position. This makes it easier to maintain the strength of the propeller fan 20' even when the airflow volume is increased by high-speed rotation.

Furthermore, as with the first embodiment, each blade, which is a three-dimensional airfoil, is formed so that its leading edge and trailing edge lie along planes that are parallel to each other. As a result, even though the gap between adjacent blades is small when the rotation speed is increased, turbulence in the air passing through the gap is suppressed, making it possible to increase the air volume as the rotation speed increases.

Next, we will explain the third embodiment of a clothes fan using Figure 12. In the third embodiment, cable rotation is limited when the power cable is connected.

Figure 12 is a partial perspective view of the third embodiment of a clothing fan, viewed from the rear.

In the clothing fan 10", as in the first embodiment, the motor mounting portion 34" of the casing 30" has a ribbed structure consisting of multiple radial ribs 34"R1 and concentric annular ribs 34"R2. The lid 60" covers the motor housing (not shown). The ring 40" here is formed in a cylindrical shape with no irregularities on the sides. The flange (not shown) of the casing 30" is also formed in a circular shape rather than a corrugated shape.

A radially protruding connection portion 55" is formed near the opening of the motor housing. The input terminal 54"M provided on the motor housing connection portion 55" is located on the inside of the lid 60", and the connection terminal of a power cable (not shown) is inserted into the input terminal 54"M.

In the third embodiment, the space S" in front of the input terminal 54"M is configured as a spatial area that restricts the rotation of the connected power cable, and when the power cable is inserted into the input terminal 54"M, it cannot be rotated to a position parallel to the ring 40". Therefore, the power cable cannot be rotated 180 degrees.

The radial ribs 39"A, 39"B that connect to the housing near the input terminal 54"M are stepped, and in this case are located symmetrically with respect to the input terminal 54"M and are identical in shape. The radial ribs 39"A, 39"B that form this front space S" are sized to a height that allows them to contact and support the power cable connection terminal when it is inserted into the input terminal 54"M.

In the rib structure of the motor mounting section 34", the circumferential arc-shaped rib 37"R2 is formed along the vicinity of the ring 40" below the other annular ribs 34"R2. The arc-shaped rib 37"R2 is connected to the annular rib 34"R2 via inclined ribs 38"A and 38"B. The inclined ribs 38"A and 38"B come into contact with the inserted power cable when it is rotated, limiting its rotational movement.

In the third embodiment, radial ribs 39"A, 39"B, which are stepped and have two steps, are shaped to come into contact with the power cable connection terminal at the step. As a result, the power cable is stably held by radial ribs 39"A, 39"B, and is positioned by contact with inclined ribs 38"A, 38"B. This makes it difficult for the power cable connection terminal to come off the input terminal 54"M.

Furthermore, because there is no space required to rotate the power cable connection terminal by 180 degrees, and no receiving section to prevent the power cable connection terminal from coming loose is provided near the side of the ring outside the space, it is possible to form a rib structure that supports the motor housing all around, and in particular, a rib structure that connects to the input terminal 54"M to maintain strength is realized. Furthermore, there is no need to increase the diameter of the motor mounting section 34" (i.e., the diameter of the casing 30") more than necessary.

This type of rib structure can also be applied to clothing fans that do not employ the configurations described in the first and second embodiments. That is, a clothing fan can be provided in which the casing housing the propeller fan has a rib structure in which concentric annular ribs intersect with radial ribs, and in which radial ribs with steps (e.g., two steps) are formed in the casing near the input terminal into which the power cable connection terminal is inserted, descending from the top of the casing toward the bottom (the outer casing surface). Clothing fans can be attached not only by screwing with a ring, but also by locking or fitting. For example, in the case of radial ribs with two steps, the height of the middle portion of the rib can be determined so that the middle portion of the radial rib comes into contact with the middle portion of the radial rib when the power cable connection terminal is inserted into the input terminal.

Previously, to prevent the power cable from coming loose from the clothing fan, it was necessary to leave a large space near the input terminal, which resulted in a lack of strength in the rib structure supporting the motor housing. However, by forming stepped radial ribs, it is possible to stably hold the power cable while minimizing the reduction in strength of the rib structure.

Next, we will explain the fourth embodiment of a clothing fan using Figure 13. In the fourth embodiment, the connection portion with the power cable extends radially from near the top (rear side) of the fan casing.

Figure 13 is a partial perspective view of the fourth embodiment of a clothing fan, viewed from the rear.

In the clothes fan 1000, as in the third embodiment, the motor mounting portion 1034 of the casing 1030 has a ribbed structure consisting of multiple radial ribs 1034R1 and concentric annular ribs 1034R2. The motor housing connection portion 55, which is covered by the lid 1060, is provided with a flexible connection portion 1100 that connects to the power cable connection terminal. The connection portion 1100 includes an input terminal portion 1110 and a straight cable portion 1120, and motor drive power is supplied via the connection portion 1100. The cable portion 1120 is made of a flexible material.

The connection part 1100 extends from the cover 1060 in the radial direction of the casing 1030 and has a length T. The connection terminal of the power cable can be inserted into the input terminal portion 1110 of the connection part 1100. By providing such a protruding connection part 1100 on the casing 1030 of the clothes fan 1000, the power cable can be easily connected to the clothes fan 1000 even when the power cable is not long enough.

Here, the length T of the connection portion 1100 extends radially beyond the casing 1030, protruding, but it is also possible to set the length T so that it does not exceed the casing 1030. The length T may be determined according to standards, etc. The shape and size of the input terminal portion 1110 may also be determined according to standards, etc. A plurality of input terminal portions 1110 of the connection portion 1100 with different shapes and sizes may be prepared according to standards, etc., and configured to be detachable from the motor housing and selectively attached. On the other hand, the direction of extension of the cable portion 1120 may be changed midway.

This type of power cable structure can also be applied to clothing fans that do not employ the structures described in the first, second, and third embodiments. That is, in a casing that houses a propeller fan, the connection portion with the connection terminal of the power cable that supplies power to the motor that drives the propeller fan can be configured so that at least a portion of it extends radially from near the center of the casing. Clothing fans can be attached not only using a ring-based screwdriver, but also by locking or fitting. For example, the connection portion can have an input terminal portion at its tip into which the power cable's connection terminal can be inserted, and at least a portion of the cable can extend in a straight line.

As in the past, when inserting the power cable's connection terminal (pin), there were cases where the position (angle) at which the clothing fan 1000 was attached made it difficult to insert due to factors such as the length of the power cable and the relationship with the mounting positions of the two clothing fans. However, by providing the above-mentioned connection section, it becomes easy to connect the power cable regardless of the mounting position of the clothing fan.

Furthermore, when the power cable is pulled while plugged in, conventional input terminals are subjected to stress, which can lead to cable deterioration and a decrease in the strength of the motor housing. However, the connection part 1100 of this embodiment allows for ample power cable length, reducing the stress on the motor housing.

The eight-blade propeller fan configuration described in the first embodiment can also be applied to clothing fans that do not have a configuration with complementary profiles on the opposing surfaces of the ring and flange, and that do not have a heat dissipation structure for the motor housing. Similarly, the motor housing heat dissipation structure can be applied to propeller fans with an even number of blades, and clothing fans that do not have a configuration with complementary profiles on the opposing surfaces of the ring and flange, and configurations with complementary profiles on the opposing surfaces of the ring and flange can be applied to propeller fans with an even number of blades, and clothing fans that do not have a heat dissipation structure for the motor housing.

Below, we will explain the results of an experiment comparing the airflow between a clothing fan of the embodiment equipped with an eight-blade propeller fan and a clothing fan of the comparative example equipped with a six-blade propeller fan.

The clothing fan of the example is equipped with an eight-blade propeller fan equivalent to the second embodiment, and is configured as a clothing fan with a fan diameter of 85 mm and a casing diameter of 105 mm. The mounting angle of each blade is within the range of 35 to 45 degrees. On the other hand, the clothing fan of the comparative example has the same fan diameter and casing diameter as the example, and also has approximately the same front and rear rib structure, and the mounting angle of each blade is approximately the same. When deployed in a blade row, the spacing in both cases is greater than the blade chord length, and the chord solidity is configured to be approximately the same between the example and the comparative example.

The following air volume tests were conducted on the clothing fans of the example and comparative examples.

Airflow measurements were taken using a vane-type anemometer (manufactured by Testo SE & Co. KGaA, Germany) and a flow strainer (rectifier). To avoid being affected by the floor or other factors during measurements, the clothing fan was placed on a special base with a casing-sized hole, and measurements were taken with the fan and flow strainer in close contact to prevent air leakage. A voltage of 15V was also supplied to the clothing fan to measure airflow.

The air volume measurement results showed that the clothing fan of the example had an air volume of 83 (L/s), while the clothing fan of the comparative example had an air volume of 73.2 (L/s). This confirmed that the eight-blade clothing fan was more effective at increasing air volume than the six-blade clothing fan.

REFERENCE SIGNS LIST 10 clothing fan 20 propeller fan 20A to 20H blades 21 hub 30 casing 32 main body 32F flange 32P ring-opposing surface 33 convex portion 34 motor mounting portion 40 ring 42 convex portion 42P flange-opposing surface 50 motor housing 52M opening 70 motor

Claims (7)

a cylindrical casing having an intake port facing outward from the clothing when attached to the clothing and an exhaust port facing toward the body when attached to the clothing ;
an axial flow propeller fan housed in an annular portion formed between the intake port and the discharge port of the casing along a casing axis , with a tip end surface of a cylindrical hub facing the intake port,
In the propeller fan, eight blades are attached to a side surface of the hub at equal or unequal intervals along the circumferential direction,
When the propeller fan is viewed from the tip end surface side of the hub along the casing axis, a leading edge and a trailing edge of each blade are curved in a rotation direction corresponding to a counterclockwise rotation of the propeller fan,
Each blade is attached with an axial width corresponding to the axial length of the side surface of the hub,
A clothing fan characterized in that the spacing between adjacent blades when deployed as a blade row is greater than the chord length of the blade. 2. The clothing fan according to claim 1, wherein the radially furthest ends of the leading and trailing edges of each of the three-dimensional blades are aligned along a plane perpendicular to the axial direction of the hub. 3. The clothes fan according to claim 1, wherein each blade is attached at an angle of 45 degrees or less to the tip surface perpendicular to the axis of the hub. 4. The clothes fan according to claim 3 , wherein each blade is attached at an angle ranging from 35 degrees to 45 degrees with respect to the tip surface perpendicular to the axis of the hub. A clothes fan according to any one of claims 1 to 4, characterized in that the projection size of the gap between adjacent blades onto a plane perpendicular to the axis of the hub is smaller than half the projection size of the blade onto a plane perpendicular to the axis of the hub. a plurality of concentric annular ribs and a plurality of radial ribs intersecting the annular ribs are provided at the intake port and the discharge port of the casing;
6. A clothing fan according to claim 1, wherein the axial length of the side surface of the hub is equal to or less than the axial length of the annular portion interposed between the inlet and outlet. Clothing comprising the clothing fan according to any one of claims 1 to 6.