Liquid sprayer pipe with inclined slits

The liquid sprayer pipe made of a flexible material has liquid spraying slits inclined in an acute angle with respect to a wall of the liquid sprayer pipe. The slits are opened with vibrations by the pressure of a liquid which passes through the liquid sprayer pipe, whereby the liquid is sprayed in a wide range and in a long distance along the liquid sprayer pipe. In the case of a cylindrical pipe, the liquid spraying slits are formed along a tangent of an inner surface of the pipe.

BACKGROUND OF THE INVENTION 
The present invention relates to a liquid sprayer pipe having liquid 
spraying slits, made of an elastic and flexible material, such as rubber, 
and particularly to a water sprayer pipe having water spraying slits which 
are formed by cutting the wall of the water sprayer pipe in an acute angle 
with respect to the wall of the sprayer pipe and whose outlets are formed 
parallel to the flow of water in the water sprayer pipe. Conventionally, a 
water sprayer pipe having a number of openings in the longitudinal 
direction of the pipe for spraying water therefrom is well-known. 
Furthermore, a water sprayer pipe having slit-shaped openings is disclosed 
in Japanese Utility Model 49-20915. However, the quantity of water sprayed 
from such slit-shaped openings is small and it is difficult to spray water 
uniformly in a wide range along the water sprayer pipe. Moreover, when the 
respective water spraying openings are spaced sufficiently, in some places 
along the water sprayer pipe, water is not sprayed. Therefore, there is a 
certain limit in the length of such water sprayer pipes. In general, when 
the water pressure is approximately 1.5 kg/cm.sup.2 and the diameter of 
the water sprayer pipe is in the range of from 8 to 12 mm, the water 
spraying range is not more than 10 m along the water sprayer pipe, and the 
sprayed water reaches 4 m or less. Naturally, the water spraying range can 
be increased by increasing the pressure and the quantity of supplied 
water. However, this needs more water pumps and water pipes, while the 
above-mentioned shortcomings of the conventional water sprayer pipes are 
not removed, but they are intensified, so that water cannot be sprayed 
uniformly in a wide range. 
SUMMARY OF THE INVENTION 
It is therefore a principal object of the present invention to provide a 
water sprayer pipe capable of spraying water uniformly in a wide range and 
in a long distance along the water sprayer pipe. 
In one embodiment of a water sprayer pipe according to the present 
invention, the water sprayer pipe is made of an elastic and flexible 
material, such as a rubber, and water spraying slits are formed by cutting 
a wall of the water sprayer pipe in an acute angle with respect to the 
wall of the pipe and in the direction parallel to the water flow in the 
water sprayer pipe. While water is not supplied to the water sprayer pipe, 
the slits are closed by the elasticity of the material of the water 
sprayer pipe, but when water is supplied to the water sprayer pipe, the 
slits are gradually opened by the pressure of water with the acute edges 
of the slits vibrated, so that water is sprayed from the slits in the form 
of very fine drops. 
In another embodiment of a water sprayer pipe according to the present 
invention, an outlet of water on an inner side of each water spraying slit 
is designed so as to be larger than an inlet of water of each water 
spraying slit, so that the water spraying angle is broadened, in 
comparison with the water spraying openings or slits of the conventional 
water sprayer pipes whose water spraying openings or slits are formed in a 
right angle with respect to the wall of the pipes and at the same time, 
the water spraying distance and range can be increased in comparison with 
the conventional water sprayer pipes. 
Particularly when the cross section of a water path of the water sprayer 
pipe is circular, it is most effective for spraying water to form the 
water spraying slits along a tangent of the water path, but as the angle 
of the water spray slits is increased from the tangent, the water spraying 
performance of the water sprayer pipe gradually becomes poor and when the 
angle is increased to about 60 degrees, the water spraying performance is 
lowered to that of the conventional water sprayer pipes having the right 
angle openings or slits. 
According to the present invention, under a water pressure, the water 
spraying pipe can be lengthened more than 5 times that of the conventional 
water spraying pipes and the water spraying range can be broadened more 
than 10 times that of the conventional water spraying pipes. 
The present invention is not only applied to the spraying of water, but 
also to the spraying of any liquids in many fields, such as farms, 
gardens, athletic fields, roads, irrigation facilities, cleaning 
facilities, snow melting facilities, coolers, and heat exchangers.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to FIG. 1 and FIG. 2, there is shown an embodiment of a water 
sprayer pipe according to the present invention, wherein a water spraying 
angle of the slits of the pipe is 45 degrees from a horizontal plane. 
Namely, the slits are formed in the water sprayer pipe in such a fashion 
that the sprayed water reaches the longest distance. 
A slit 2 is formed parallel to a water flow in a water sprayer pipe 1, and 
is formed in the direction of a tangent at a point X (refer to FIG. 2) on 
an inner surface 4 of the water sprayer pipe 1. The slit 2 extends up to a 
point Y on an outer surface 5 of the water sprayer pipe 1 (refer to FIG. 
2). A water inlet 6 and a water outlet 7 of the slit 2 are formed in the 
same size and parallel to the water flow of the water sprayer pipe 1. A 
slit 3 is also formed in the water sprayer pipe 1, with a distance l from 
the slit 2, symmetrically with respect to a line passing through a center 
of the water sprayer pipe 1. 
In the case where a number of such slits as the slit 2 and the slit 3 are 
formed in the water sprayer pipe 1 with a certain distance between them in 
the longitudinal direction of the water sprayer pipe 1, when a pressure 
water is supplied into the water sprayer pipe 1, the peripheral portions 
of the water sprayer pipe 1, in which the slits, such as the slits 2 and 3 
are formed, are expanded greater in the direction of the diameter of the 
pipe 1 in comparison with the other peripheral portions of the water 
sprayer pipe 1 by the pressure of water since the peripheral portions 
having such slits therein become weaker than the other portions, whereby 
the slits are deformed and expanded and at the same time, the pressure 
water is sprayed from each slit, and within each slit, there are formed 
turbulent flows of water, and an acute angle inner portion 4a which is in 
contact with the water inlet 6 and the other acute angle outer portion 5a 
which is in contact with the water outlet 7 are caused to make complicated 
and minute vibrations, whereby water is divided into fine drops and is 
sprayed from the water outlet 6 of the slit 2. 
In the case of the slit 3 adjacent the slit 2, the same vibrations occur as 
in the slit 2 when water is sprayed from the slit 2. 
Such a water spray effect depends upon to what extent the inner portion 4a 
and the outer portion 5a are acute, which is determined by an angle of 
inclination of the slit 2 at the inner surface 4 and at the outer surface 
5 of the water spray tube 1. 
According to an experiment conducted by the inventor of the present 
invention, the limit angle of inclination from a tangent .alpha. shown in 
FIG. 2 is 45 degrees, and in the range of from more than 45 degrees to 
approximately 60 degrees, the water spray effect was found small and in 60 
degrees or greater, the effect was the same as that of the conventional 
slits with .alpha.=90.degree.. Therefore, in the present invention, the 
angle of inclination of the slits is set in the range of from a tangent of 
the inner surface of the water sprayer pipe 1 to 45 degrees from the 
tangent. 
In the above-mentioned embodiment, water is sprayed from opposite sides of 
the water sprayer pipe 1. However, the water sprayer pipe 1 can be 
designed so as to spray water from one side of the water sprayer pipe 1. 
Furthermore, as shown in FIG. 3, slits 12 and 13 can be formed so as to 
spray water nearly horizontally. Alternatively, as shown in FIG. 4, slits 
22 and 23 can be formed so as to spray water vertically. 
Referring to FIG. 5, there is shown a further embodiment of a water sprayer 
pipe 11 according to the present invention. This embodiment comprises a 
plurality of water paths whose vertical cross sections are rectangular. In 
this case, slits 32, 32a, 33 and 33a are all inclined with respect to the 
respective inner surfaces 14 and outer surface 15 within a range of not 
more than 45 degrees. 
Referring to FIG. 6, there is shown a further embodiment of a water sprayer 
pipe 41 according to the present invention, wherein a slit 42 is designed 
in such a fashion that the width S' of an outlet 47 is larger than the 
width S of an inlet 46. In this design, water is sprayed more efficiently 
and the spraying angle is more widened in comparison with the previously 
mentioned water sprayer pipes. 
Referring to FIG. 7, there is shown an enlarged fragmentary sectional view 
of the slit portion of the water sprayer pipe 41 which is deformed by the 
supply of pressure water. To be more specific, the slit 42 of the water 
sprayer pipe 41 is shown by solid lines, in which the water inlet 46 of 
the inner wall 44 of the slit 42 extends in the direction of a tangent of 
the inner wall 44 up to the water outlet 47 of the outer wall 45. The 
water path of the slit 42 is elastically closed tightly when no pressure 
is applied to the slit 42. However, as the pressure of water is gradually 
increased, the diameter of the water spray tube 41 is increased over the 
whole length of the water sprayer pipe 41 and the diameter of the 
slit-formed portion becomes greater than that of the other portions, and 
the slit 42 is opened to position 42.sub.1, to position 42.sub.2, so that 
the water inlet 46 is slightly opened, for instance, up to position 
46.sub.1, while the water outlet 47 is more opened to position 47.sub.1, 
to position 47.sub.2, whereby water spraying is started. According to an 
experiment conducted by the inventor of the present invention, initially 
when the water pressure is not high enough, water is sprayed in two lines 
from opposite ends of the water outlet 47. However, as the water pressure 
increases, water is sprayed from the whole range of the water outlet 47 so 
that the spraying of water is made more efficiently and the spraying 
distance and the spraying angle are increased, whereby the water spraying 
is made uniformly in a wide range. 
In the present invention, the slits are formed in a water sprayer pipe in 
an inclined angle with respect to the pipe wall. Such slits can be formed 
by a cutting device with a keen edge, such as a razor, but a cutting 
method employing a keen blade of a low frequency vibration type with a 50 
Hz of frequency and an approximately 1 mm of amplitude is preferable. 
However, the conventional cutting methods of an ultrasonic vibration type 
are not suitable for the present invention since heat is generated in the 
cutting portions of the water sprayer pipe, which deforms the cutting 
portions.