JPH11165097A - Water-film screen forming nozzle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-film screen forming nozzle by which an almost semicircular water-film screen capable of projecting an image without reducing the image even in the inside if a house where the distance of spouting water is limited. SOLUTION: The front end of a cylinder 3 is closed by a backplate, the upper-half peripheral wall above the horizontal plane 5 passing through the center 0 of the cylinder 3 is notched close to the backplate to form an opening 6, and the cross-sectional area of flow facing the opening of the downstream nozzle part in the cylinder 3 is formed by a V-sectional small-area part 3X below the horizontal plane 5 and a semicircular-sectioned large-area part 3×1 above the horizontal plane 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water film screen forming nozzle for forming a water film screen such as a projection water screen.

[0002]

2. Description of the Related Art FIGS. 8 and 9 show a conventional water film screen forming nozzle. This water film screen forming nozzle 1 has a high pressure water inlet 2 at the rear end.
The front end of a cylindrical body 3 (hereinafter, referred to as a cylindrical body 3) provided with is closed by a contact plate 4, and an upper half peripheral wall 3 </ b> A above a horizontal plane 5 passing through the center O of the cylindrical body 3 and a lower part below the horizontal plane 5. Half peripheral wall 3B
The part near the horizontal plane 5 in is slightly cut out in the axial direction,
It has a structure in which an opening 6 is formed. Therefore, the high-pressure water supply system 7 composed of the pump 7A and the high-pressure water supply pipe 7B is connected to the high-pressure water inlet 2, and the high-pressure water introduced into the cylinder 3 from the high-pressure water inlet 2 by operating the pump 7A. After colliding with the plate 4, the opening 6
To form a water film screen 8 indicated by a solid line in FIG.

In the conventional water film forming nozzle 1, the shape above the horizontal plane 5 passing through the center O of the cylindrical body 3 in the contact plate 4 is semicircular. Therefore, the cylinder 3
The distance from the center O to the outer end 4A of the plate 4 is equal at all points on the 1/2 circle, and the frictional resistance between the high-pressure water jetted from the opening 6 and the plate 4 is 1/2 circle. Equal at all points above. For this reason, the high-pressure water is ejected radially outward from the outer end 4A of the abutment plate 4 at a substantially constant speed.

If the gravity of water is ignored, the outer end 4A of the plate 4
The jet distance of the high-pressure water from the outside to the radial direction is equal in a semicircle, and the water film screen 8 is formed in a substantially semicircular shape as shown by a broken line in FIG. However, actually, due to the gravity of the water, the jet distance of the high-pressure water from the outer end 4A of the plate 4 to the outside in the radial direction is the longest in the horizontal direction and in the vicinity thereof, and gradually becomes shorter as it is displaced in the vertical direction. And the shortest in the vertical direction. For this reason, the water film screen 8
As shown by the solid line, the height H is smaller than the width W and is formed in a crescent shape.

On the other hand, an image 9 having a horizontally long rectangle as shown by a virtual line in FIG. 10 is projected on the water film screen 8. If the water film screen 8 is formed in a crescent shape in which the height H is smaller than the width W, despite the fact that the horizontally long rectangular image 9 is projected, both upper corners of the image 9 are displayed. The portions 9A, 9A protrude from the water film screen 8 as shown by oblique lines. Such protrusion can be eliminated by increasing the height of the water film screen 8 by increasing the jetting speed of water from the opening 6 to increase the jetting distance. However, if the jetting speed is increased to increase the jetting speed and the jetting distance is increased in order to obtain the height H, the jetting distance in the horizontal direction where the influence of gravity is small and the jetting distance in the vicinity thereof is greatly increased. In such a case, it is limited to increase the jetting distance of water in order to gain the height H. For this reason, there is a disadvantage that the image 9 has to be reduced as shown by the dashed line.

[0006]

That is, in the conventional water film screen forming nozzle, a crescent-shaped water film screen having a small height relative to the width is formed, and the height of the water film screen is reduced indoors. In order to earn money, it is limited to increase the jetting speed of water and increase the jetting distance, so that there is a disadvantage that the image must be reduced.

In order to increase the height of the water film screen, the present invention increases the jetting speed of the water and suppresses the jetting distance in the horizontal direction and its vicinity even if the jetting distance is increased. It is an object of the present invention to provide a water film screen forming nozzle capable of forming a substantially semicircular water film screen capable of projecting an image without reducing the image even indoors where the ejection distance of the water film is limited.

[0008]

In order to achieve the above object, according to the present invention, a downstream end of a cylindrical body provided with a high-pressure water inlet at an upstream end is closed by a plate, and at least the cylindrical body is closed. In a water film screen forming nozzle in which an opening is formed by notching a peripheral wall of an upper half portion above a horizontal plane passing through the center of the body in the vicinity of the abutment plate, a water passage cross section of a cylindrical body downstream end facing the opening A small area portion below the horizontal plane whose shape passes through the center,
It is characterized by being formed by a large area portion on the horizontal plane upper side passing through the center. Further, the invention according to claim 2 is characterized in that the small area portion is formed such that its size is gradually reduced from the middle in the upstream / downstream direction to the downstream end portion of the cylindrical body, and from the upstream side to the downstream side. It is characterized by an upward slope toward.

According to the first aspect of the present invention, the amount of high-pressure water ejected from the small area portion is smaller than the amount of high-pressure water ejected from the large area portion. For this reason, the initial velocity of the high-pressure water jetting laterally from the outer end of the plate when hitting the plate is smaller than the initial velocity of the high-pressure water jetting upward from the outer end of the plate when hitting the plate. That is, the spread in the lateral direction is smaller than the spread in the upward direction. As a result, it is possible to form a substantially semicircular water film screen having a small horizontal spread and a large upward spread as compared with the conventional crescent-shaped water film screen. According to the second aspect of the present invention, since the size of the small area portion is gradually reduced from the upstream side to the downstream side, the amount of the high-pressure water below the horizontal plane is gradually reduced and guided to the opening. Because of this, the flow in the cylinder becomes smooth. Further, since the small area portion is inclined with an upward gradient from the upstream side to the downstream side, the upward force applied from the high pressure water flow flowing through the small area portion to the high pressure water flow flowing through the large area portion is gradually increased. As a result, it acts so as to further increase the initial velocity of the high-pressure water jetted upward from the outer end of the plate when hitting the plate.

[0010]

An embodiment of the present invention will be described below with reference to the drawings. The same or corresponding portions as those of the water film forming screen nozzle described in the conventional example are denoted by the same reference numerals and described. 1 to 3, a water film screen forming nozzle 1 closes a front end of a cylindrical body 3 (hereinafter, referred to as a cylindrical body 3) having a high-pressure water inlet 2 at a rear end thereof with a contact plate 4. The upper wall 3A above the horizontal plane 5 passing through the center O and the lower wall 3B slightly lower than the horizontal plane 5 are cut out parallel to the plate 4 to form an opening 6. I have. A high-pressure water supply system 7 (not shown) composed of a pump 7A and a high-pressure water supply pipe 7B is connected to the high-pressure water inlet 2 as in the conventional example.

The cylindrical body 3 has an inlet 31 provided with a high-pressure water inlet 2 at the upstream end, a rectifying section 32 provided adjacent to the downstream of the inlet 31, and a rectifying section 32 adjacent to the downstream of the rectifying section 32. The upstream nozzle portion 33 provided, the intermediate nozzle portion 34 provided adjacent to the downstream side of the upstream nozzle portion 33, and the downstream end of the intermediate nozzle portion 34 are provided, and the front end is And a downstream nozzle portion 35 having the opening 6 and being closed.

The inlet portion 31 and the rectifying portion 32 are vertically symmetrical with respect to the horizontal plane 5 passing through the center O of the cylindrical body 3, and are formed to have a uniform circular cross section whose inner diameter is uniform in the axial direction. The intermediate nozzle portion 34 and the downstream nozzle portion 35
It is constituted by a taper tube having a regular circular cross section whose upper and lower sides are symmetrical with respect to a horizontal plane 5 passing through the center O of the cylindrical body 3 and whose inner diameter gradually decreases toward the downstream side. A flow contracting member 10 whose thickness gradually increases from the upstream side to the downstream side is attached to an inner surface of the downstream side nozzle portion 35 below the horizontal plane 5 passing through the center O of the cylindrical body 3. Accordingly, the cross-sectional shape of the water passage facing the opening 6 of the downstream side nozzle portion 35 includes a small area portion 3X having a V-shaped cross section below the horizontal plane 5 passing through the center O,
Large area portion 3X having a semicircular cross section above horizontal plane 5 passing through center O
1 and the size of the small area portion 3X is gradually reduced from the upstream side to the downstream side and is inclined at an ascending gradient.

In the above configuration, the high-pressure water introduced from the high-pressure water inlet 2 to the inlet 31 of the cylinder 3 is rectified by the rectifier 32 by operating the pump 7A shown in the conventional example of FIG. It is guided to the upstream nozzle section 33. Upstream nozzle section 33, intermediate nozzle section 32, and downstream nozzle section 35
Is constituted by a tapered tube whose inner diameter is gradually reduced toward the downstream side, so that the flow velocity is increased by passing through this region, and the high-pressure water collides with the abutment plate 4 and then opens along the abutment plate 4. It gushes from part 6.

The downstream cross section of the cylindrical body 3 facing the opening 6 is formed by a small area 3X below the horizontal plane 5 passing through the center O and a large area 3X1 above the horizontal plane 5 passing through the center O. Therefore, the amount of high-pressure water ejected from the small-area portion 3X is smaller than the amount of high-pressure water ejected from the large-area portion 3X1. For this reason, the initial velocity of the high-pressure water jetted laterally from the outer end of the plate 4 against the plate 4 is equal to the initial velocity of the high-pressure water jetted upward from the outer end of the plate 4 on the plate 4. It is smaller than the speed and the lateral spread is smaller than the upward spread. As a result, even if the jetting speed is slightly increased to increase the height and the jetting distance is increased, the jetting distance in the horizontal direction is suppressed, so even in an indoor where the jetting distance of water is limited, as shown in FIG. By forming the substantially semicircular water film screen 8, the image 9 can be projected without being reduced.

In particular, the small area portion 3X of the downstream side nozzle portion 35
Is gradually reduced in size from the upstream side to the downstream side and is inclined with an upward slope.
Since the amount of high-pressure water on the lower side can be guided to the opening 6 while gradually reducing the amount of high-pressure water on the lower side, the flow in the downstream nozzle 35 becomes smooth, and the small area portion 3X rises from the upstream side to the downstream side. Due to the inclination, the upward force applied from the high-pressure water flow flowing through the small-area portion 3X to the high-pressure water flow flowing through the large-area portion 3X1 is gradually increased.
As a result, it acts so as to further increase the initial velocity of the high-pressure water jetted upward from the outer end of the plate 4 against the plate 4, thereby facilitating the formation of the substantially semicircular water film screen 8. .

In the above embodiment, the downstream side nozzle 35
And the contraction member 10 are manufactured separately, and the constitution is described in which the contraction member 10 is attached to the inner surface of the downstream side nozzle portion 35.
The downstream nozzle section 35 and the contraction member 10 may be manufactured integrally. Further, the cross-sectional shape of the small area portion 3X is not limited to a sharp V-shape, but may be a rounded semi-elliptical shape (half-oval shape).

On the other hand, portions of the upper half peripheral wall 3A above the horizontal plane 5 passing through the center O of the cylindrical body 3 and the lower half peripheral wall 3B below the horizontal plane 5 near the horizontal plane 5 are parallel to the plate 4. Although the opening 6 is formed by notching, FIG.
As shown in FIG. 5, the opening 6 may be formed by gradually cutting away from the contact plate 4 from the lower end to the upper end.
Also, as shown in FIG. 6, the opening 6 is formed by cutting out from the lower end to a position slightly above the horizontal plane 5 in parallel with the contact plate 4, and gradually cutting away from the lower end in a direction away from the contact plate 4. Is also good. Further, in the above embodiment, the cylinder 3
The opening 6 is formed by notching a portion near the horizontal plane 5 in the upper half peripheral wall 3A above the horizontal plane 5 and the lower half peripheral wall 3B below the horizontal plane 5 passing through the center O of As shown in FIG. 7, a horizontal plane 5 passing through the center O of the cylindrical body 3
Only the upper peripheral wall 3A in the upper half is cut out, and the opening 6
May be formed.

[0018]

As described above, according to the present invention, the initial velocity at which high-pressure water is ejected outward from the outer end of the plate is slowed in the horizontal direction, and gradually increased as it is displaced in the vertical direction. And by giving the speed distribution that becomes the fastest in the vicinity, even if the ejection speed is slightly increased to increase the height and the ejection distance is increased, the ejection distance in and around the height direction can be suppressed, A water film screen having a substantially semicircular shape can be formed even indoors where the jetting distance is limited, and the image can be projected without being reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing an embodiment of the present invention.

FIG. 2 is a front view of FIG.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is a front view showing an example of a water film screen formed according to the present invention.

FIG. 5 is an enlarged vertical sectional side view showing a modification of the opening.

FIG. 6 is an enlarged vertical sectional side view showing another modification of the opening.

FIG. 7 is an enlarged vertical sectional side view showing still another modification of the opening.

FIG. 8 is a longitudinal sectional side view of a conventional example.

FIG. 9 is a sectional view taken along line BB of FIG. 8;

FIG. 10 is a front view showing a conventional water film screen.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water film screen forming nozzle 2 High pressure water inlet 3 Cylindrical body 3A Peripheral wall of upper half part of cylindrical body 4 This plate 5 Horizontal plane 6 Opening 3X Small area 3X1 Large area O Center of cylindrical body

Claims (2)

[Claims] 1. A downstream end of a cylindrical body provided with a high-pressure water inlet at an upstream end thereof is closed by an abutment plate, and at least a peripheral wall of an upper half portion above a horizontal plane passing through the center of the cylindrical body is provided near the abutment plate. In the water film screen forming nozzle which is notched to form an opening, a water flow cross-sectional shape of the cylindrical body downstream end facing the opening has a small area portion below a horizontal plane passing through the center, and a horizontal plane passing through the center. A water film screen forming nozzle formed by an upper large area portion. 2. The small area portion is formed such that its size is gradually reduced from the middle in the upstream / downstream direction to the downstream end portion of the cylindrical body, and the small area portion is inclined with a rising gradient from the upstream side to the downstream side. The water film screen forming nozzle according to claim 1, wherein: