VENTILATION VENT CAP

Abstract

A ventilation vent cap includes a cylindrical main body fitted into a duct placed in the exterior wall of a building so as to communicate between an interior and an exterior; a shielding portion disposed in the exterior via a support member attached to an outdoor-side end surface of the cylindrical main body; and a cover portion blocking vertically an upper part of an air passage extending between the outdoor-side end surface and the shielding portion. The shielding portion is in the shape of a cone whose apex is located in the air passage and above an opening upper end of the cylindrical main body.

Description

TECHNICAL FIELD

The present invention relates to a ventilation vent cap.

BACKGROUND ART

A conventional ventilation vent cap includes a shielding plate on the exterior side to protect from wind and rain (see, for example, Patent Literature 1). FIG. 8 is a sectional view of a configuration of a conventional ventilation vent cap disclosed in Patent Literature 1.

As shown in FIG. 8, the ventilation vent cap includes cylindrical main body 102 placed in duct 101, conical shielding portion 104 fixed to cylindrical main body 102 via support member 103, and cover portion 105 covering cylindrical main body 102 and shielding portion 104.

In such a conventional ventilation vent cap, its upper part is covered by cover portion 105, causing exhaust stream 106 to collide with shielding portion 104 and flow downward. The shape of cover portion 105 and shielding portion 104 can cause exhaust stream 106 to have a high pressure loss, and the ventilator to have a low performance.

CITATION LIST

Patent Literature

Patent Literature 1: Japanese Patent Unexamined Publication No 2009-222270

SUMMARY OF THE INVENTION

The ventilation vent cap of the present invention includes a cylindrical main body fitted into a duct placed in the exterior wall of a building so as to communicate between an interior and an exterior; a shielding portion disposed in the exterior via a support member attached to an outdoor-side end surface of the cylindrical main body; and a cover portion blocking vertically an upper part of an air passage extending between the outdoor-side end surface and the shielding portion. The shielding portion is in the shape of a cone whose apex is located in the air passage and above an opening upper end of the cylindrical main body.

This configuration prevents the exhaust stream from flowing toward the cover portion and then turning into a turbulent flow near the cover portion. This prevents an increase in the pressure loss and a decrease in the performance of the ventilator.

BRIEF DESCIPTION OF DRAWINGS

FIG. 1 is a cross sectional view of a ventilation vent cap according to a first exemplary embodiment of the present invention, and an exhaust stream.

FIG. 2 is a perspective view of the ventilation vent cap according to the first exemplary embodiment and the exhaust stream.

FIG. 3 is a front view where the ventilation vent cap according to the first exemplary embodiment is installed.

FIG. 4 is a cross sectional view of a ventilation vent cap according to a second exemplary embodiment of the present invention, and an exhaust stream.

FIG. 5 is a perspective view of the ventilation vent cap according to the second exemplary embodiment and the exhaust stream.

FIG. 6 is a cross sectional view of a ventilation vent cap according to a third exemplary embodiment of the present invention, and an exhaust stream.

FIG. 7 is a cross sectional view of a ventilation vent cap according to a fourth exemplary embodiment of the present invention, and an exhaust stream.

FIG. 8 is a sectional view of a configuration of a conventional ventilation vent cap.

DESCRIPTION OF EMBODIMENTS

Exemplary embodiments of the present invention will be described as follows with reference to the drawings.

First Exemplary Embodiment

FIG. 1 is a cross sectional view of a ventilation vent cap according to a first exemplary embodiment of the present invention, and an exhaust stream. FIG. 2 is a perspective view of the ventilation vent cap and the exhaust stream. As shown in FIGS. 1 and 2, ventilation vent cap 18 includes cylindrical main body 5, shielding portion 8, and cover portion 10. Shielding portion 8 is cone 14 having circular bottom surface 8a. Cone 14 has apex 13 which is located in air passage 9 and is above opening upper end 5a of cylindrical main body 5. Main cylindrical body 5 is fitted into duct 4, which is placed in exterior wall 1 of a building so as to communicate between interior 2 and exterior 3. Shielding portion 8 is disposed in exterior 3 via support member 7, which is on outdoor-side end surface 6 of cylindrical main body 5. Air passage 9 is a space between outdoor-side end surface 6 and shielding portion 8. Cover portion 10 blocks vertically upper part of air passage 9 (the upper part in FIG. 1). As shown in FIG. 2, a line connecting apex 13 with lower end 11 of circular bottom surface 8a and a line connecting lower end 11 with upper end 12 of circular bottom surface 8a form an angle θ.

When ventilation is started with the above-described ventilation vent cap, exhaust stream 17 passes through cylindrical main body 5 and then flows along the surface of cone 14 of shielding portion 8. Apex 13 of cone 14 is located above opening upper end 5a of cylindrical main body 5, so that exhaust stream 17 can be prevented from flowing toward cover portion 10 and then turning into turbulent flow in the vicinity of cover portion 10. Thus, exhaust stream 17 passed through cylindrical main body 5 is smoothly discharged along the surface of cone 14 of shielding portion 8. This maintains the low pressure loss and high performance of the ventilator.

As shown in FIG. 2, exhaust stream 17 leaves air passage 9 through lower end 11 of circular bottom surface 8a substantially at an angle of θ with respect to exterior wall surface 1a. This prevents exhaust stream 17 from colliding with exterior wall surface 1a, so that exterior wall surface 1a can be kept clean.

Cover portion 10 is placed in air passage 9. More specifically, cover portion 10 is placed on the upper side of ventilation vent cap 18, that is, on the ceiling 19 side under the eaves shown in FIG. 3, which is a front view where the ventilation vent cap according to the first exemplary embodiment is installed. Thus, even if ventilation vent cap 18 is installed near ceiling 19, cover portion 10 placed over air passage 9 as shown in FIG. 2 prevents exhaust stream 17 from flowing upward and soiling ceiling 19.

Second Exemplary Embodiment

In a second exemplary embodiment of the present invention, the same components as in the first exemplary embodiment are denoted by the same reference numerals, and the description thereof is omitted. The following description will be focused on the difference between the first and second exemplary embodiments. The second exemplary embodiment differs from the first exemplary embodiment in the shapes of shielding portion 8 and cover portion 10.

FIG. 4 is a cross sectional view of a ventilation vent cap according to the second exemplary embodiment, and an exhaust stream. FIG. 5 is a perspective view of the ventilation vent cap and the exhaust stream. As shown in FIG. 4, shielding portion 8 is in the shape of cone 23 whose apex 13 faces cylindrical main body 5. The base angle of cone 23 is δ. As shown in FIG. 5, cover portion 10 has cover rim on an outdoor-side-end-surface side 16 on the outdoor-side end surface 6 side, cover rim on the outdoor-side-end-surface side 16 being longer than cover rim on a circular-bottom-surface side 15 on the circular bottom surface 8a side of shielding portion 8. Thus, cover portion 10 has end side 26, which extends obliquely downward from circular bottom surface 8a to outdoor-side end surface 6.

When ventilation is started with the above-described ventilation vent cap, as shown in FIG. 4, exhaust stream 24 passes through the lower part of cylindrical main body 5 and then flows along the surface of cone 23 of shielding portion 8.

On the other hand, as shown in FIG. 5, exhaust stream 25 passes through the upper part of cylindrical main body 5, and flows along cover rim on the circular-bottom-surface side 15 on the circular bottom surface 8a side of cover portion 10, then passes through a substantially V shaped region S formed by the region of cover portion 10 that is in the vicinity of end side 26 and shielding portion 8, thereby being discharged to exterior 3 from under end side 26.

At this moment, as shown in FIG. 5, exhaust stream 25 flowing along cover portion 10 is discharged to exterior 3 from the vicinity of an apex T of the region S on the shielding-portion 8 side. Exhaust stream 24, on the other hand, is discharged to exterior 3 smoothly from under end side 26. This prevents an increase in the pressure loss and a decrease in the performance of the ventilator.

It is desirable that the angle δ is in the range of 30° to 70°.

Third Exemplary Embodiment

In a third exemplary embodiment of the present invention, the same components as in the second exemplary embodiment are denoted by the same reference numerals, and the description thereof is omitted. The following description will be focused on the difference between the second and third exemplary embodiments. The third exemplary embodiment differs from the second exemplary embodiment in the shape of the shielding portion.

FIG. 6 is a cross sectional view of a ventilation vent cap according to the third exemplary embodiment and an exhaust stream. As shown in FIG. 6, shielding portion 38, which has circular bottom surface 38a, is composed of cones 33 and 34 having different base angles 33a and 34a, respectively, instead of being in the shape of a cone. Shielding portion 38 projects into air passage 9. More specifically, shielding portion 38 is a combination of cone 33 having base angle 33a and cone 34 having base angle 34a. Base angle 34a is smaller than base angle 33a. The use of shielding portion 38 having such a shape allows exhaust streams 24 and 25 to flow more smoothly along cones 33 and 34, thereby preventing an increase in the pressure loss and a decrease in the performance of the ventilator.

Base angle 33a is preferred to be large so that exhaust streams 24 and 25 can be prevented from flowing toward exterior wall 1, but large base angle 33a requires shielding portion 38 to have a large thickness B. The large thickness B causes shielding portion 38 to block opening 21 of cylindrical main body 5, making it necessary to increase a distance C between exterior wall surface 1a and circular bottom surface 38a.

In the present third exemplary embodiment, shielding portion 38 is composed of two cones 33 and 34, and base angle 34a of cone 34 is smaller than base angle 33a of cone 33. This allows exhaust streams 24 and 25 to flow along cones 33 and 34, while shielding portion 38 can be as thin as possible.

Exhaust streams 24 and 25 flow as follows. As approaching cone 34, exhaust streams 24 and 25 flow radially outward along the surface of cone 34. When reaching cone 33, exhaust streams 24 and 25 flow along cone 33, and leave ventilation vent cap 18 at lower end 11, thereby being discharged to exterior 3. Exhaust streams 24 and 25 never flow toward exterior wall 1 because they have components in the direction of base angle 33a with respect to exterior wall surface 1a at lower end 11.

Ventilation vent cap 18 has a lower pressure loss (a larger amount of ventilation) with increasing distance between center 20 of shielding portion 38 and outdoor-side end surface 6. As lower end 11 has a larger angle (base angle 33a), exhaust streams 24 and 25 are more apart from exterior wall surface la, making exterior wall 1 more soil resistant (it is desirable that the maximum angle of lower end 11 is 70°). Thus, shielding portion 38 is composed of cones 33 and 34, allowing an appropriate distance between center 20 and outdoor-side end surface 6, thereby reducing an increase in the amount of ventilation and increasing the angle of lower end 11. As a result, exterior wall 1 can be more soil resistant, and the projection allowance C can be smaller, making ventilation vent cap 18 slim and aesthetically designed. Shielding portion 38 is composed of two cones 33 and 34 in the present third exemplary embodiment, but may alternatively be composed of three or more cones.

Fourth Exemplary Embodiment

In a fourth exemplary embodiment of the present invention, the same components as in the second exemplary embodiment are denoted by the same reference numerals, and the description thereof is omitted. The following description will be focused on the difference between the second and fourth exemplary embodiments. The fourth exemplary embodiment differs from the second exemplary embodiment in the shape of the shielding portion.

FIG. 7 is a cross sectional view of a ventilation vent cap according to the fourth exemplary embodiment, and an exhaust stream. As shown in FIG. 7, shielding portion 48 is composed of spherical surfaces 42 and 43 having different radiuses, instead of being in the shape of a cone. Shielding portion 48 projects into air passage 9.

Shielding portion 48, which is composed of two spherical surfaces 42 and 43, can smoothly change the direction of exhaust streams 24 and 25 that have passed through the interior from a straight-ahead direction J to a blow-off direction G. This reduces an increase in the amount of ventilation. At lower end 11 where exhaust stream 24 leaves ventilation vent cap 18, exhaust stream 24 flows toward exterior 3 at an angle substantially orthogonal to exterior wall 1 without soiling exterior wall 1. The surface of shielding portion 48 is composed of two spherical surfaces 42 and 43 smoothly connected to each other without ridges. As a result, no problems occur such as dust accumulation in the ridges, so that the surface of shielding portion 48, and hence the appearance of the product itself can be kept clean.

INDUSTRIAL APPLICABILITY

The ventilation vent cap according to the present invention is useful as, for example, an outdoor hood mounted on the exterior wall of a building.

REFERENCE MARKS IN THE DRAWINGS

• 1 exterior wall
• 1a exterior wall surface
• 2 interior
• 3 exterior
• 4 duct
• 5 cylindrical main body
• 5a opening upper end
• 6 outdoor-side end surface
• 7 support member
• 8, 38, 48 shielding portion
• 8a, 38a circular bottom surface
• 9 air passage
• 10 cover portion
• 11 lower end
• 13 apex
• 14 cone
• 15 cover rim on the circular-bottom-surface side
• 16 cover rim on the outdoor-side-end-surface side
• 17, 24, 25 exhaust stream
• 18 ventilation vent cap
• 19 ceiling
• 20 center
• 21 opening
• 23, 33, 34 cone
• 26 edge
• 33a, 34a base angle
• 25 42, 43 spherical surface

Claims

1. A ventilation vent cap comprising:

a cylindrical main body fitted into a duct placed in an exterior wall of a building so as to communicate between an interior and an exterior;

a shielding portion disposed in the exterior via a support member attached to an outdoor-side end surface of the cylindrical main body; and

a cover portion blocking vertically an upper part of an air passage extending between the outdoor-side end surface and the shielding portion, wherein

the shielding portion is in a shape of a cone whose apex is located in the air passage and above an opening upper end of the cylindrical main body.

2. A ventilation vent cap comprising:

a cylindrical main body fitted into a duct placed in an exterior wall of a building so as to communicate between an interior and an exterior;

a shielding portion disposed in the exterior via a support member attached to an outdoor-side end surface of the cylindrical main body, the shielding portion being in a shape of a cone whose apex faces the cylindrical main body; and

a cover portion blocking vertically an upper part of an air passage extending between the outdoor-side end surface and the shielding portion, wherein

the cover portion has a cover rim on an outdoor-side-end-surface side, the cover rim being longer than a cover rim on a circular-bottom surface side of the shielding portion.

3. The ventilation vent cap of claim 2, wherein

instead of being in the shape of a cone, the shielding portion is composed of a plurality of cones having different base angles and projects into the air passage.

4. The ventilation vent cap of claim 2, wherein

instead of being in the shape of a cone, the shielding portion is composed of a plurality of spherical surfaces having different radiuses, and projects into the air passage.