WO2003048625A1

WO2003048625A1 - Joint for plumbing

Info

Publication number: WO2003048625A1
Application number: PCT/KR2002/002238
Authority: WO
Inventors: Sukyoon Kim
Original assignee: Sukyoon Kim
Priority date: 2001-12-03
Filing date: 2002-11-29
Publication date: 2003-06-12
Also published as: AU2002365787A1; KR200269760Y1

Abstract

The present invention relates to a plumbing joint for allowing pipes to be rapidly and easily connected thereto or separated therefrom. The plumbing joint of the invention adopts an easy insertion type based upon the principle of a wedge instead of screws. The plumbing joint of the invention forms trapezoid sections in an upper portion of a spring and install jaws respectively in the trapezoid section in order to fundamentally remove defects owing to gaps as well as to reduce the number of parts, the size of the body and manufacturing cost. Through-holes are formed in the joint entrances to facilitate assemblage. The springs are directly pressed through the holes pushing down the jaws so that the jaws stop actions as wedges when the pipes are pulled out. As a result, excellent effect is realized in maintenance and repair. Th invention promotes use of the insertion type joint which is applicable to valves as well as piping for gas, chemicals, vehicles and so on.

Description

JOINT FOR PLUMBING

Technical Field

The present invention relates to a plumbing joint for connecting pipes, and more particularly, to a plumbing joint for metal pipes which allows the pipes to be more rapidly and easily connected thereto or separated therefrom.

Background Art

In general, a number of joints are used in various piping including electric power lines for construction, telephone lines, fluid piping for water, gas, waste water and so on and pressure piping for air or hydraulic facilities. For example, the joints are used in the form of linear joints, L-shaped joints and T-shaped joints.

Although a joint adopting a bolt-fastening policy allows reliable and permanent piping, it is difficult to fasten and/or release bolts in a limited space.

Also, the piping operation disadvantageouly requires time and labor by large amounts. Therefore, an easy insertion type joint is used to simply connect pipes while completing the piping operation without any additional tools even in a limited working space. The easy insertion type joint is based upon the principle of a wedge, and widely used in mechanics such as a chuck. Recently, the easy insertion type joint is also used in small-sized plastic piping.

Fig. 1 is a partial sectional view illustrating a conventional easy insertion type joint for plumbing that couples pipes. Hereinafter description will be given to a structure of the plumbing j oint shown in Fig. 1. As shown in Fig. 1, the conventional plumbing joint has a body 10 with a taper 13 which gradually decreases in diameter outwardly. A jaw-coupling 14 is installed in the body 10, with jaws 16 being inserted into the insert holes. At the other side of the spring 17 which is supporting the jaw-coupling 14, a packing 19 and a packing support 18 are installed to maintain water sealing. In connecting two pipes 30, an end of each pipe 30 is pushed into the jaw-coupling 14 at an entrance of the plumbing joint. In separation of the pipe 30 from the plumbing joint, the jaw-coupling 14 is pressed to release the pipe 14 from the jaw 16 so that the pipe 30 can be separated from the plumbing joint. The pipe jaws 16 are adopted to increase/decrease in an inside diameter in sliding movement along the inner periphery of the taper 13 to fix or release the pipe 30 which is inserted into the jaw-coupling 14.

Hereinafter a following description will present the operation of the conventional plumbing joint configured as above. When the pipe 30 is inserted, the jaws 16 increase in their inside diameters while sliding in a direction same as the pipe 30. Then, the pipe 30 enters into the jaw-coupling 14 up to a limit projection 12 without any significant resistance. At fixation of the pipe 30 in position, the packing 19 isolates an inner space of the pipe 30 from the outside thus water leaking is prevented. Elastic force of the spring 17 presses the jaws 16 toward the entrance of the plumbing joint so that the jaws 16 are securely fixed between an outer surface of the pipe 30 and an inner surface of the taper 13.

When a force is applied to extract the pipe 30, a larger resistant force is applied to the jaws 16 that located between the inner surface of the taper 13 and the outer surface of the pipe 30 so act as wedges. Therefore, the jaws 16 are operated to prevent extraction of the pipe 30 when the pipe 30 is simply pulled out.

It is necessary to press and retreat the jaw-coupling 14 to extract the pipe 30. Then, the spring 17 is contracted to form a hollow gap between the jaws 16 and the inner face of the taper 13. In this position, the pipe 30 can be extracted when it is pulled out by hands.

Disclosure of Invention

The conventional plumbing joint adopts the jaw-coupling 14 to allow insertion of the jaws 16 and the jaw-coupling 14, protruded outside, is pressed down to allow extraction of the pipe. The jaw-coupling 14 is made of plastic to save manufacturing cost.

This causes the following problems:

1. A gap is formed between the plastic jaw-coupling 14 and the metal jaw 15 so that jaw-coupling 14 is frequently not pressed after the pipes 30 are fastened. As time passes, this problem occurs more frequently. This is a fatal defect in maintenance.

2. In many cases, the jaw-coupling 14 is not smoothly pressed by hands, excessive force is applied to the jaw-coupling 14 for separating pipes 30. Further, it is difficult to manually press a jaw-coupling with a larger diameter. 3. The plumbing joint has a number of parts and thus it is difficult to assemble the joint. As a result, the plumbing joint has poor productivity and economic efficiency.

4. Since the plastic part is protruded beyond the joint body 10 , it is readily deformed under external impact and when hardened, it damages stability of the joint. Under external pressure, the spring may be contracted via the jaw-coupling 14 thereby stopping the operation of the jaws 16.

5. Because the jaw-coupling 14 is outwardly contacted, it is difficult to seal the plumbing joint in case of burying the pipes.

6. Because the jaw-coupling 14 is outwardly exposed, it is difficult to fix the plumbing joint in case of preventing rotation of the pipes 30.

Therefore, the present invention has been made in view of the foregoing problems and it is an object of the invention to provide a plumbing joint which can simply connect pipes to one another without any additional operation as well as minimize the number of components so as to improve productivity and achieve excellent economical efficiency, and which enables easy maintenance and repair and maximize durability and stability of products.

It is another object of the invention to provide a plumbing joint capable of preventing rotation of coupled pipes while ensuring easy burying of the coupled pipes. Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. i the plumbing joint that provided to fixedly receive pipes through both ends of the body 20 thereof, a limit projection 21 is formed at a central portion, in such a manner as to have an inner diameter same as those of pipes 30 (only one is shown) to be connected. A certain portion of the body from the limit projection tightly contacts the outer periphery of the pipe and supports the pipes. From this first portion a second portion starts with enlarged diameter for installing packing. A third portion or tapers 29 abruptly enlarged at the end of second portion in inner diameter and decreased in diameter or inwardly tapered toward entrances 26. The body 20 is perpendicularly bent at ends of the tapers 29 to form the entrances

26 through which the pipes 30 are inserted.

The packing 22 is inserted in each of the second portion of the body to maintain water sealing of the joint. The packing 22 is made of rubber or silicon, and is in close contact with the outer periphery of the pipe 30 to maintain sealing.

A spring 24 is installed subsequent to the packing 22, and an annular packing support 23 is placed between the packing 22 and the spring 24 to uniformly transfer elastic force of the spring 24 to the packing 22. Alternatively, a portion of the body 20 receiving the packing 22 and the spring 24 can be designed to have a cylindrical configuration rather than a tapered configuration.

The last wind 24a of the spring 24 adjacent to the body entrance 26 has at least two trapezoid sections into which jaws 25 for fixing the pipe 30 are inserted. The jaws 25 in the trapezoid sections are inserted between an inner surface of the body and an outer surface of the pipe. Each of the jaws 25 is smoothly formed in an outer section that contacts the body 20. The each jaw 25 has comb-patterned grooves in a portion which contacts the pipe, and this portion has a hardness higher than that of the pipe to maximize a frictional force to the pipe. The jaw 25 inserted into the trapezoid sections of the spring 24 moves in a gap between the body 20 and the pipe 30 within a certain limit according to elastic force of the spring 24 to act as wedges.

The jaw 25 is projected at both sides thereof so that it is inserted into the pertinent trapezoid section of the spring 24 but fitted by the spring 24 so that it does not slip inward. Otherwise, it is preferred that the jaw 25 is grooved to receive an upper portion of the pertinent trapezoid section of the spring 24 and projected at a lower end to wrap the spring 24.

The body portion where the jaws 25 are moved owing to elastic force of the spring 24 has the taper 29 which is inwardly decreased in diameter toward the entrance 26. The end of the taper 29 is perpendicularly bent inward so that the jaw 25 does not move out of the entrance 26. A snap ring 31 for the sake of convenience in assembly can substitute the entrance.

The jaw 25 is projected toward a center at the entrance so that the end of the pipe 30 pushes the jaw 25 along with the same when the pipe 30 is inserted into the joint.

At least one through-hole 27 is formed at the entrance 26, perpendicular to an insertion direction of the pipe. A chopstick-like elongated tool can be inserted through the through-hole 27 to press the spring 24 to draw the pipe 30 out of the joint. A fixing piece 28 is inserted between the pipe 30 and the entrance 26 to act as a wedge using the through-hole 27 as a projection, thereby preventing rotation of the pipe 30.

When two pipes 30 are connected to each other by the present invention having the above configuration, an end in each of the pipes 30 is pushed into the entrance of the body 20 of the joint while pressing the jaws 25 in the trapezoid sections of the spring 24. Then, the each pipe 30 touches the limit projection 21 in the central portion of the joint.

The spring 24 is compressed since the each pipe 30 presses by its end the jaws 25 when it is inserted inward.

The jaw 25 inserted into the pertinent trapezoid section of the spring moves toward the inner enlarged portion of the body 20 while compressing the spring 24 based upon force of the entering pipe 30. Then, the jaw 25 is slightly pressed toward the inner wall of the body and up to the outer wall of the pipe. The pipe 30 is continuously inserted in this fashion to closely contact with the limit projection 21 and water sealed by the packing. When the jaw 25 is pressed up to the outer wall of the pipe 30, the compressed spring 24 elastically rebounds pressing a jaw 25A so that the jaw 25 slides along an inclined face in the inner wall of the body 20 until it is held between the inner wall of the body and the outer wall of the pipe. Then, the jaw 25 acts as a wedge 25B preventing retraction of the pipe 30 out of the body 20. Since the pipe 30 is also stopped by the limit projection 21, the pipe 30 is securely fixed .

However, the inserted pipe 30 is rotatable and thus external force will rotate the pipe 30 damaging the surface thereof with the jaw 25. The fixing piece 28 having a protrusion is inserted into a gap between the body entrance and the pipe in a position of the through-hole 27 so that the fixing piece 28 as a wedge to prevent rotation of the pipe 30.

The fixing piece 28 inserted between the entrance 26 and the pipe 30 includes a first portion which contacts the pipe 30 in the form of a portion of a cylinder and a second portion which contacts with the body 20 in the form of a protrusion. The protrusion part inserted into the through-hole 27 makes the fixing piece 28 to readily fix the pipe 30.

A linear projected pattern may be formed in the first portion of the fixing piece 28 which contacts the pipe 30 along the insertion direction of the pipe 30 in order to prevent rotation of the pipe 30 in a more effective manner. In separating the pipe 30 from the plumbing joint 10, the fixing piece 28 is pulled out using the projection of the through-hole 27 as a point of application in a lever. An elongated tool is inserted into the through-hole 27 to press the spring so that the jaws 25 inserted into the trapezoid sections of the spring move downward to wider portions of the body 20 along the taper 29 which gradually widens inward. As a result, the pipe 30 is released from the wedge action of the jaws 25 and thus readily pulled out of the joint.

As set forth above, the present invention eliminates the jaw-coupling from the conventional plumbing joint and installs the through-hole therein to reduce the number of parts, to reduce defective proportion, to improve productivity and to prolong life time of the products. The length of the joint body is reduced as much as the thickness of the jaw-coupling between the spring and the jaws. Also, the parts can be easily assembled.

The joint is endurable against external impact since it has no outwardly protruded portions. The invention also adopts a method of direct pressing the spring through the through-hole in separating pipes. This method fundamentally prevents the occurrence of gap between plastic jaw-coupling and metal jaws thus it can enhance stability of the joint.

Brief Description of the Drawings The above and other objects, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments of the invention in conjunction with the accompanying drawings, in which:

Fig. 1 is a partial sectional view of a conventional plumbing joint that couples pipes; Fig. 2 is a partial sectional view of a plumbing joint according to an embodiment of the invention;

Fig. 3 is a sectional view illustrating the position of jaws engaged with a pipe shown in Fig. 2; Fig. 4 is a front elevation view of the plumbing joint coupled with a pipe, seen from an entrance thereof;

Fig. 5 is a side elevation view of a spring of the invention;

Fig. 6 illustrates the jaw coupled with the spring of the invention;

Fig. 7 illustrates a fixing piece of the invention; and Fig. 8 illustrates a snap ring of the invention.

10: body of conventional joint for plumbing 12,21: limit projection

13,29: tapers 14: jaw-coupling 16,25: jaw 17,24: spring

18,23 : packing support 19,22: packing

20: body of present joint for plumbing 26: entrance

27 : through-hole 28 : fixing piece

30: pipe 31 : snap ring

Best Mode for Carrying Out the Invention

The best mode of the invention will be described in reference to Fig. 2. In order to realize the best mode of the invention, the spring 24 is designed to have at least two trapezoid sections into which jaws are inserted. It is most stable that the spring 24 has three trapezoid sections. The each jaw 25 is heat treated or made of metal powder to have a hardness higher than those of pipes 30. The jaw 25 is grooved for receiving an upper portion of each of the trapezoid sections in the spring 24, and at a lower portion which contacts the joint body, projected downward to wrap a lower portion of the each trapezoid section, thereby preventing inward slip of the jaw 25.

The snap ring 31 is used in the body entrance 26 to simplify processing and assemblage.

The snap ring 31 is designed to have at least one through-hole, which preferably have the number same as that of the jaws 25.

A chopstick-like elongated tool can be inserted into the through-hole 27 of the snap ring 31 to press the spring 24 and thus move the jaws 25 downward so that the pipes 30 can be readily pulled out of the joint.

The joint has no parts protruded beyond the body and thus is readily sealed when it is buried. Also, external impact is not transferred to the spring 24.

The fixing piece 28 can prevent rotation of the pipes.

Industrial Applicability The plumbing joint of the present invention receives pipes without deformation in the pipes owing to screwing or enlargement of the pipes and thus can be optimally adopted to thin stainless pipes. Also the plumbing joint of the invention can be used as a connector for pipes made of copper or special steel that are resistive against rust. The plumbing joint of the invention itself has no screw structures and thus is inexpensive in manufacturing cost. Since connection between the pipes is simply completed by pressing the pipes into the joint, operation requires a small area with a working speed raised up to 5 to 10 times. As a result, the plumbing joint of the invention can largely reduce personnel expenses. Since pressing the spring through the through-hole can separate the pipes, maintenance is reliable and simple.

The plumbing joint of the invention can be used in water supply piping using a number of pipes, and applicable to valves. Also, the plumbing joint of the invention can be widely used in piping lines for gas, chemicals, vessels and vehicles.

Claims

What Is Claimed Is;

1. A joint for plumbing, which fixedly receive the pipes through both entrances thereof, comprises: a body 20 having a limit projection 21 formed in a central portion, the limit projection 21 having an inner diameter identical with those of the pipes 30 which inserted into the plumbing joint, a first portion extended from the limit projection 21 toward the entrances to tightly contact the outer peripheries of the pipes and to support the pipes, a second portion enlarged in inner diameter from the first portion and extended respectively to both ends, a third or taper portion abruptly enlarged from the second portion and gradually tapered or reduced in inner diameter toward the entrances 31, and the entrances 31 being perpendicularly bent from ends of the taper portions 29 for receiving the pipes 30; packings 22 each installed within each of the second portions of the body and tightly contacting the outer periphery of each of the pipes 30 to perform water sealing; packing supports 23 each installed between each packing 22 and each of springs 24 for separating the each packing 22 from the each spring 24; the springs 24 each supported at one end by each of the packing supports 23 and having winds, with a last wind having at least two trapezoid sections for receiving jaws 25 and contacting an adjacent wind; the jaws 25 inserted respectively into the trapezoid sections of the springs 24, each of the jaws 25 having a smooth surface contacting each of the taper portions 29 of the body 20 and a comb-patterned surface contacting each of the pipes 30 for maximizing friction against the each pipe 30 and being inserted into between the inner periphery of the body and the outer periphery of the each pipe for fixing the each pipe; and one or more through-holes 27 formed in each of the entrances 26 of the body 20 in an insertion direction of the each pipe 30, into which a fixing piece 28 is insertable to prevent rotation of the each pipe 30, and through which the each spring 24 can be contracted in pulling the each pipe 30 out.