Background Art Generally, for cultivation of crops, water should be supplied to the crops so as to promote the growth of crops under cultivation.

When such water supply is needed in large quantities, it is very difficult to supply water to the crops under cultivation by manpower alone, so a water pump is generally employed to supply water to the crops.

In such a case, the water pump is connected to a main water supply pipe, the main water supply pipe is connected to a T-shaped or linear branch pipe positioned along the furrows of farmland, the T-shaped or linear branch pipe is connected to water supply hoses, water dividing hoses or so on, and each of the water supply hoses, water dividing hoses or so on connected in this manner can be bent at a certain angle through an elbow.

However, every conventional elbow is comprised of a linear tubular body bent at an angle of 90°, in which hose connecting portions formed on both ends of the conventional elbow also form a fixed angle of 90° relative to each other.

Therefore, two water supply hoses connected to the hose connecting portions of the conventional elbow form a fixed angle of 90° relative to each other in a normal state.

As a result, the above-described characteristic of the conventional elbow restricts

the bending of the furrows of farmland to an angle of 90°.

For example, when the furrows are formed at an obtuse angle larger than 90° or an acute angle smaller than 90°, it is difficult to employ the conventional elbow having a fixed angle of 90 to connect water supply hoses to each other, Even though two water supply hoses are connected to each other through the conventional elbow having a fixed angle of 90° and are unnaturally arranged at an obtuse or acute angle, the water supply hoses shift to form an angle of 90° with each other to coincide with the angle of the conventional elbow as the water supply hoses are swelled due to internal water pressure. Accordingly, the water supply hoses creep out of the furrows of farmland and damage the crops under cultivation beside the furrows unless the water supply hoses arranged at an obtuse or acute angle are firmly held by hose securing devices.

On the other hand, when the hose securing devices are employed to secure water supply hoses, the reorientation of a water supply line is carried out in such a manner that the hose securing devices are removed from the ground, the water supply hoses are desirably reoriented, and the hose securing devices are fixed back into the ground, thereby imposing excessive physical labor on a worker.

Disclosure of the Invention Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a variable angle elbow for connection of water supply hoses, which can be varied in angle to connect water supply hoses at various angles, thereby maximizing its convenience of use.

In order to accomplish the above object, the present invention provides a variable angle elbow for connection of water supply hoses, comprising a first elbow part having a

linear, tubular shape ; a second elbow part having a linear, tubular shape, the second elbow part being rotatably connected to one end of said first elbow part at its one end such that the first and second elbow parts form an angle of 90° relative to each other in a normal state; and a sealing ring disposed between the contact surfaces of the first and second elbow parts for maintaining the air-tightness of the elbow.

Brief Description of the Drawings The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which : Fig, 1 is a perspective view of a variable angle elbow according to a first embodiment of the invention; Fig. 2 is a front view showing the variable angle elbow of first embodiment; Fig. 3 is a sectional view showing the variable angle elbow of the first embodiment ; Fig. 4 is a detailed view of the principal portion of Fig. 3 ; Fig. 5 is a plan view showing the first elbow part of the variable angle elbow of the first embodiment; Fig. 6 is a plan view of the closing member of the variable angle elbow of the first embodiment ; Fig, 7 is a side view of Fig. 6; Fig. 8 is an exploded, partial sectional view showing the assembly of the angle variable elbow of the first embodiment; Fig. 9 is a view showing the variable angle elbow of the first embodiment with its second elbow part rotated to allow a bolt to be fastened into the closing member and the

first elbow part; Fig. 10 is a view showing the variable angle elbow of the first embodiment with its second elbow part rotated at various angles for use; Fig. 11 is a front view of a variable angle elbow according to a second embodiment of the invention ; Fig. 12 is a sectional view of Fig. 11; Fig. 13 is a detailed view of the principal portion of Fig. 12; and Fig. 14 is a view showing the variable angle elbow of the second embodiment with first and second elbow parts rotated at various angles for use.

Best Mode for Carrying Out the Invention As illustrated in Figs. 1 to 9, a variable angle elbow for connection of water supply hoses in accordance with the present invention includes a first elbow part 11 having a linear, tubular shape. A second elbow part 12 having a linear, tubular shape is rotatably connected to one end of the first elbow part 11 at its one end such that the first and second elbow parts 11 and 12 form an angle of 90° relative to each other in a normal state. A sealing ring 20 is disposed between the contact surfaces of the first and second elbow parts 11 and 12 for maintaining the air-tightness of the elbow 10.

In this case, the contact surfaces of the first and second elbow parts 11 and 12 are each formed to be inclined at an angle of 45°, and are brought into contact with each other when the first and second elbow parts 11 and 12 are assembled into the elbow 10.

The first elbow part 11 is provided on the inner circumferential surface of its contact end with a curved interlocking portion 110 consisting of a curved interlocking groove 111 and a curved interlocking projection 112, and on one side of its contact end with a cutout 113,

The second elbow part 12 is provided on the outer circumferential surface of its contact end with a circular interlocking portion 120 consisting of a circular interlocking groove 121 and a circular interlocking projection 122, and on the inner circumferential surface of its contact end with a stepped portion 123 to allow the second elbow part 12 to be interlocked with the first elbow part 11 with the sealing ring 20 seated on the stepped portion 123 of the second elbow part 12.

A closing member 30 is fitted into the cutout 113 to close the cutout 113, and is secured into the first elbow part 11 by means of a bolt 40. The closing member 30 is provided at both side ends with two fitting projections 311, and on its inner circumferential surface with a curved interlocking projection 312 to form an entire circle together with the curved interlocking projection 112 of the first elbow part 11.

In such a case, a locking depression 114 is formed on the bottom of the cutout 113, while a locking protrusion 314 is formed on the bottom surface of the closing member 30 to be engaged with the locking depression 114.

In order to improve the sealing function of the sealing ring 20, a V-shaped groove 210 is formed along the inner circumferential surface of the sealing ring 20. Accordingly, when water is supplied into the elbow 10, the V-shaped groove 210 of the sealing ring 20 is spread out by the hydraulic pressure of water supplied, so the contact portions of the first and second elbow parts 11 and 12 become airtight.

The contact surfaces of the first and second elbow parts 11 and 12 are each inclined at an angle of 45°, so there are formed portions of the contact surfaces outside the outer diameters of the first and second elbow parts 11 and 12 (the portions outside the one- dot chain line of Fig. 5).

The second elbow part 12 is interlocked with the first elbow part 11 through the cutout 113 of the first elbow part 11 with the circular interlocking projection 120 of the second elbow part 12 interlocked with the curved interlocking groove 110 of the first

elbow part 11.

As shown in Fig. 9, when the closing member 30 is slid into the cutout 113 and the second elbow part 12 is rotated on the contact surface of the first elbow part 12 at an angle of 90°, the portion of the contact surface outside the outer diameter of the first elbow part 11 is exposed. At this time, the bolt 40 is fastened into the closing member 30 and the first elbow part 11.

According to the first embodiment of the invention, as shown in Fig. 10, the elbow 10 can be utilized in the state in which the hose connecting portions 1 la and 12a of the first and second elbow parts 11 and 12 are respectively connected to the water supply hoses H and the first and second elbow parts 11 and 12 form relative to each other the angle suitable to surrounding topographical conditions.

Meanwhile, Figs. 11 to 14 show an elbow in accordance with a second embodiment of the invention, which is discriminated from the elbow of the first embodiment in that the first and second elbow parts 11 and 12 can form an acute angle smaller than an angle of 90° relative to each other, In more detail, an intermediate elbow part 50 is interposed between the first and second elbow parts 11 and 12 of the elbow 10, the first and second elbow parts 11 and 12 are rotatably connected to the intermediate elbow part 50, and two sealing rings 20 are respectively interposed between the contact portions of the first elbow part 11 and the intermediate elbow part 50 and between the contact surfaces of the second elbow part 12 and the intermediate elbow part 50 to maintain the air-tightness of the elbow 10.

One end of the intermediate elbow part 50 is provided on its outer circumferential surface with a circular interlocking portion 510 consisting of a circular interlocking groove 511 and a circular interlocking projection 512, and on its inner circumferential surface with a stepped portion 513 to allow the intermediate elbow part 50 to be interlocked with the first elbow part 11 with the sealing ring 20 seated on the stepped portion 513 of the intermediate elbow part 50, The other end of the intermediate elbow part 50 is provided on its inner circumferential surface with a curved interlocking portion 520 consisting of a curved interlocking groove 521 and a curved interlocking projection 522, and on its one side with a cutout 523, Two closing members 30 are fitted into the cutouts 113 and 523 to close the cutouts 113 and 523, respectively, and are secured into the first and second elbow parts 11 and 12 by means of bolts 40, respectively, Each of the closing members 30 is provided at both side ends with two fitting projections 311, and on its inner circumferential surface with a curved interlocking projection 312 to form an entire circle together with the curved interlocking projection 112 of the first elbow part 11.

According to the second embodiment of the invention, as shown in Fig. 14, the elbow 10 can be utilized in the state in which the hose connecting portions 1 la and 12a of the first and second elbow parts 11 and 12 are respectively connected to the water supply hoses H and the first and second elbow parts 11 and 12 form an acute angle relative to each other.

Industrial Applicability As described above in detail, the present invention provides a variable angle elbow, which can be varied in angle to connect water supply hoses at various angles when the orientation of a water supply line is required according to surrounding topographical conditions, thereby improving its convenience of use.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.