Fitting assembly for internally sealing a corrugated tube and a method for using the same

Abstract

A fitting assembly for corrugated tubing is provided including a body, an insert, locking means and a bushing. The body includes first connecting means. The locking means includes second connecting means. The insert is sealingly engaged with the body and includes a transition area of increased outside diameter. The bushing includes an inwardly projecting protrusion for engagement with a trough disposed on an external surface of a corrugated tube. The first and second connecting means engage to removably secure the bushing, an end of the corrugated tube and at least a portion of the insert within the body and the locking means to pinch a circumferential section of the corrugated tube between the protrusion and the transition area, and to seal an internal surface of the circumferential section with the transition area.

Description

FIELD OF THE INVENTION

This present invention is generally directed to a fitting assembly for sealing a corrugated tube and more specifically directed to sealing a portion of the fitting assembly with an internal section of the corrugated tube.

BACKGROUND OF THE INVENTION

In plumbing applications, sections of pipe, tubing, or conduit are typically connected to one another to provide for the flow of fluids within a system. In connecting these sections, it is generally desirable to seal the connections in order to avoid or at least minimize the loss of fluid due to leaks or fugitive emissions. Various techniques exist for sealing the connections. Two of such techniques include welding and the use of adhesives.

When sections of pipe, tubing, or conduit are connected by welding, disconnection for service, repair, routine maintenance, or restructuring of the system often involves cutting or otherwise physically separating the sections. Disconnection usually involves cutting using high speed rotary tools. When the sections being cut apart are metal, sparks are often generated, which creates an undesirable condition. Even if the sections being cut are plastic, dust or flying debris may be generated. In either case, the integrity of the pipe, tubing, or conduit is compromised, and new sections must be fabricated and reinstalled.

When sections are connected with adhesives, disconnection may also involve cutting or some other physical method of separation (e.g., melting the adhesive), or it may involve effecting a chemical change to the adhesive. Melting the adhesive or using chemical techniques to separate the sections are often time consuming and costly practices. Reassembly of the system generally involves adhesively connecting new systems of pipe.

Therefore, connectors and fittings which provide releasable sealing capability are preferred for applications where disassembly is likely. Various connectors and fittings having releasable sealing capability are used to seal the outside surfaces of sections of pipe, tubing, or conduit with one another. However, in applications using corrugated tubing, inside and outside surfaces have ridges and troughs making sealing with prior art connectors and fittings ineffective. In addition, sealing on the outside surface of tubing is undesirable because walls of the tubing can become unintentionally distorted when the connector is secured thereby increasing the potential for leakage.

There is a need to provide a fitting or connector for releasably sealing corrugated tubing where the sealing is made inside the tubing. Prior art connectors and fittings for addressing these needs were either too expensive, inefficient, ineffective, or a combination of all of these. Based on the foregoing, it is the general object of the present invention to improve upon or overcome the problems and drawbacks of the prior art.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a fitting assembly for a corrugated tube includes a body, an insert, a locking device, and a bushing. The body includes a first connector, a first bore, a first shoulder, and a second shoulder. The insert is receivable on the second shoulder and has a second bore, two external surfaces (one of increased outside diameter), and a transition area between the two external surfaces. The locking device has a second connector that is selectively receivable on the first connector. The bushing is slidable over the insert and securable in the body and the locking device via the first and second connectors.

According to another aspect of the present invention, an internally sealable fitting assembly includes a body having a bore; an insert coaxially positioned in the bore; a castellated bushing receivable over said insert; and a locking device selectively receivable on the body. The insert is dimensioned to receive a corrugated tube thereon. Receiving the locking device on the body urges the bushing against the corrugated tube to clamp the corrugated tube against the insert.

When the fitting is assembled, the first and second connectors engage to releasably secure the bushing, the end of the corrugated tube, and at least a portion of the insert within the body and the locking device. In addition, a circumferential section of the corrugated tube is clamped between the protrusion and the transition area to seal an internal surface of the circumferential section with the transition area.

In another aspect of the present invention, a method of installing a fitting assembly for a corrugated tube includes providing the fitting assembly, sliding a locking device of the fitting assembly onto the corrugated tube, sliding a bushing of the fitting assembly onto the corrugated tube, positioning a protrusion on the bushing into a trough in the corrugated tube, abutting an insert against a surface in a body to sealingly engage the insert with the body, sliding the locking device, the bushing, and the corrugated tube over the insert, and engaging the locking device and the body to releasably secure the bushing, an end of the corrugated tube, and at least a portion of the insert within the body and the locking device. When the locking device and the body are fully engaged, a circumferential section of the corrugated tube is clamped between the protrusion and the insert to seal the corrugated tube.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded cross sectional view of the fitting assembly for a corrugated tube.

FIG. 2 is a cross sectional view of the fitting assembly installed on a section of corrugated tube.

FIG. 3 is a view of detail A of FIG. 2 illustrating a circumferential section of the corrugated tube held between the projection and the transition area.

FIG. 4 is a top view of an embodiment of a castellated bushing.

FIG. 5 is a cross sectional view of the castellated bushing shown in FIG. 4.

FIG. 6 is a cross sectional view of an embodiment of the body having the insert integral therewith.

FIG. 7 is a cross sectional view of locking means having the bushing integral therewith.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, a fitting assembly for sealing an end of a corrugated tube to create a gas or liquid seal is shown at 10. The fitting assembly 10 includes a body 12, an insert 14, a locking device 16, and a bushing 18 and can be used between lengths of corrugated tube, as an adapter to another coupling device or fitting, or to terminate a length of corrugated tube. Sealing is effected between an inner surface of the corrugated tube and an outer surface of the insert 14 received in an end of the corrugated tube.

The body 12 includes a first connector 20 having male threads, a first bore 22, a first shoulder 24, and a second shoulder 26. The first bore 22 transitions to a reduced cross section 28 at the first shoulder 24, and the reduced cross section transitions to a further reduced cross section 30 at the second shoulder 26. While the first connector 20 is shown as having male threads, the present invention is not limited in this regard as other connecting means may also be utilized including but not limited to bayonet type connections. The body 12 may also have male threads 25 located on an end opposite the end at which the first connector 20 is shown to facilitate the connection to any other device having connectable female threads. In the alternative, the body 12 may be capped at the end opposite the end at which the first connector 20 is shown.

The insert 14, which provides for the free flow of fluid (or at least negligible or minimal restriction of fluid flow), has a second bore 23 and a transition area 32. The transition area 32 is defined by a curved surface that extends radially from a portion of the external surface of the insert to another portion of the external surface having an increased outside diameter. The insert 14 is coaxially received in the bore 22, and at least a portion of one end 34 of the insert 14 abuts the second shoulder 26 to sealingly engage the insert with the second shoulder. While the insert 14 is described as being sealing engaged with the second shoulder 26, the present invention is not limited in this regard as the insert may be sealingly engaged with the reduced cross section 28, any suitable surface of the body 12, or a combination thereof.

The bushing 18 is a castellated member defined by a plurality of splits formed, cut, or otherwise disposed at a first end 40. An inwardly projecting protrusion 42 is located at the first end 40. The inwardly projecting protrusion 42 is configured such that as the bushing 18 is received over corrugated tubing, the splits allow the bushing to flex so that the surfaces of the inwardly projecting protrusion are received on the external surfaces of the corrugation.

The locking device 16 is a member having a through bore 39 extending therethrough. A second connector 36 defined by female threads is located in the through bore. 39 proximate one end in which the bushing 18 is received. The opposing end includes a receiving shoulder 38 on which the bushing may be received. The locking device 16 is open at the end having the second connector 36 to receive the bushing 18, the insert 14, and the body 12 and is also open at the opposite end to allow the corrugated tube to extend therethrough. While the second connector 36 is described as having female threads, the present invention is not limited in this regard as other connectors may also be utilized including, but not limited to, bayonet-type connections.

Referring to FIG. 2, the first connector 20 on the body 12 and the second connector 36 on the locking device 16 engage to releasably secure the body and the locking device together. An opposing end 50 of the bushing 18 is seated on the receiving shoulder 38 of the locking device 16. Securing the body 12 and the locking device 16 together urges the bushing and an end 47 of the corrugated tube 48 over the insert 14 towards the first shoulder 24. The first connector 20 and the second connector 36 engage to seal the corrugated tube 48 to the insert 14 and to secure the bushing 18, the end 47 of the corrugated tube, and at least a portion of the insert within the body 12 and the locking device 16.

Referring now to FIG. 3, when the fitting assembly 10 is properly assembled with a corrugated tube 48, the protrusion 42 on the bushing 18 engages with a trough 44 in or formed by an external surface 46 of the corrugated tube. When the protrusion 42 engages the trough 44, a circumferential section 52 of the corrugated tube 48 is clamped between the protrusion and the transition area 32, thereby sealing an internal surface 54 of the circumferential section with the transition area. The sealing engagement between the internal surface 54 and the transition area 32 is maintained until the body 12 is released relative to the locking device 16, which causes the bushing 18 and the insert 14 to move in opposite directions, thereby releasing the internal surface from the transition area.

Referring now to FIGS. 4 and 5, the bushing 18 is shown as having four splits 56 extending through the protrusion 42, the splits terminating between the first end 40 and the opposing end 50. The splits 56 are circumferentially disposed around the bushing 18 for allowing the bushing to flex when sliding the bushing axially along the corrugated tube 48 shown in FIGS. 2 and 3. While four splits 56 are illustrated, the present invention is not limited in this regard as the bushing may have any number of cuts to allow the bushing to flex.

Referring now to FIG. 6, a body 212 is shown having an integral insert 214. The insert 214 is attached to the body 212 at a first shoulder 224. A transition area 232 is formed on the exterior surface of the insert 214. A connector 220 having male threads is formed on the body 212 to allow the body to be connected to a locking device.

Referring now to FIG. 7, a locking device 316 is shown having an integral bushing 318. The bushing 316 is shown having splits 356 for allowing the bushing to flex when the bushing is pushed axially along the corrugated tube 48 shown in FIGS. 2 and 3.

Referring generally to FIGS. 1-6 the insert 14, 214 is manufactured from a material softer than the corrugated tube 48. Similarly, the body 12, 212 is manufactured from a material softer than the corrugated tube 48. While the insert 14, 214 is said to be softer than the corrugated tube 48, the present invention is not limited in this regard as in another embodiment of the present invention the insert may be manufactured from a material which is as hard as or harder than the corrugated tube. Although the body 12, 212 is said to be softer than the corrugated tube 48, the present invention is not limited in this regard as in another embodiment the body may be manufactured from a material which is as hard as or harder than the corrugated tube.

A method of using the fitting assembly for the corrugated tube 48 as shown in FIGS. 1-5 includes the steps of providing the fitting assembly 10; sliding the locking device 16 onto the corrugated tube 48; sliding the bushing 18 onto the corrugated tube; positioning the protrusion 42 into the trough 44; abutting the insert 14 against the second shoulder 26 to sealingly engage the insert with the body 12; sliding the locking device, the bushing, and the corrugated tube over the insert towards the first shoulder; and engaging the first and second connectors to removably secure the bushing, an end 47 of the corrugated tube, and at least a portion of the insert within the body by clamping a circumferential section 52 of the corrugated tube between the transition area and the protrusion, thereby sealing an internal surface 54 of the circumferential section with the transition area.

Another method of using the fitting assembly for the corrugated tube as shown in FIG. 6 includes the steps of providing a fitting assembly in which the body 212 is integral with the insert 214; sliding the locking device onto the corrugated tube; sliding the bushing onto the corrugated tube; positioning the protrusion in the trough of the corrugated tube; sliding the locking device, the bushing, and the corrugated tube over the insert 214; and engaging the first and second connectors to releasably secure the bushing and an end of the corrugated tube within the body by clamping the corrugated tube and sealing an internal surface of the corrugated tube against insert.

Another method of using the fitting assembly for a corrugated tube as shown in FIG. 7 includes the steps of providing a fitting assembly in which the bushing 318 is integral with the locking device 316; sliding the integral bushing and locking device onto the corrugated tube; positioning the protrusion 342 of the bushing in the trough of the corrugated tube; sliding the corrugated tube over the insert; and engaging first and second connectors on the body and locking device, respectively, to releasably secure the bushing, an end of the corrugated tube, and at least a portion of the insert within the body by clamping the corrugated tube and sealing an internal surface of the corrugated tube against insert.

Although the present invention has been disclosed and described with reference to certain embodiments thereof, it should be noted that other variations and modifications may be made, and it is intended that the following claims cover the variations and modifications within the scope of the invention.

Claims

1. A fitting assembly for a corrugated tube comprising: a body having first connecting means, a first bore, a first shoulder in said first bore, and a second shoulder in said first bore; an insert having a second bore, a first external surface, a second external surface of increased outside diameter, and a transition area intermediate said first external surface and said second external surface, said insert being receivable in said first bore; locking means having a through bore, a receiving shoulder in said through bore, and second connecting means selectively receivable on said first connecting means; and a bushing slidable over said insert and securable in said body and said locking means, a first end of said bushing having an inwardly projecting protrusion for engagement with a trough disposed on an external surface of a corrugated tube.

2. The fitting assembly of claim 1, wherein said first bore transitions to a reduced cross section at said first shoulder and wherein said reduced cross section transitions to a further reduced cross section at said second shoulder.

3. The fitting assembly of claim 1, wherein at least a portion of one end of said insert abuts at least a portion of said second shoulder, and wherein said insert is sealingly engaged with said body.

4. The fitting assembly of claim 1, wherein a second end of said bushing seats on said receiving shoulder for urging said bushing and an end of said corrugated tube over said insert towards said body.

5. The fitting assembly of claim 1, wherein said first connecting means and said second connecting means engage to releasably secure said bushing, said end of said corrugated tube, and at least a portion of said insert within said body and said locking means.

6. The fitting assembly of claim 5, wherein the engagement of said first connecting means and said second connecting means clamps a circumferential section of said corrugated tube between said protrusion and said transition area to seal an internal surface of said circumferential section with said transition area.

7. The fitting assembly of claim 1 wherein said bushing has a plurality of splits axially extending though said protrusion, said splits terminating between said first end and a second end of said bushing, wherein said splits are circumferentially disposed around said bushing to allow said bushing to flex when sliding said bushing along said corrugated tube.

8. The fitting assembly of claim 1 wherein said insert is integral with said body.

9. The fitting assembly of claim 1, wherein said bushing is integral with said locking means.

10. The fitting assembly of claim 1 wherein said insert is made from a material that is harder than said corrugated tube.

11. The fitting assembly of claim 1 wherein said insert is made from a material that is softer than said corrugated tube.

12. The fitting assembly of claim 1 wherein said body is made from a material that is harder than said corrugated tube.

13. The fitting assembly of claim 1 wherein said body is made from a material that is softer than said corrugated tube.

14. The fitting assembly of claim 1 wherein said first connecting means comprises male threads and wherein said second connecting means comprises female threads.

15. An internally sealable fitting assembly, comprising: a body having a bore; an insert coaxially positioned in said bore, said insert being dimensioned to receive a corrugated tube thereon; a castellated bushing receivable over said insert and said corrugated tube; and a locking device selectively receivable on said body; wherein receiving said locking device on said body urges said bushing against said corrugated tube to clamp said corrugated tube against said insert.

16. The internally sealable fitting assembly of claim 15, wherein said bushing comprises a protrusion disposed at the castellated end.

17. The internally sealable fitting assembly of claim 16, wherein said protrusion is receivable in a trough of said corrugated tube to clamp said corrugated tube against said insert.

18. The internally sealable fitting assembly of claim 15, wherein said insert is integral with said body.

19. The internally sealable fitting assembly of claim 15, wherein said bushing is integral with said locking device.

20. The internally sealable fitting assembly of claim 15, wherein said insert comprises a radially-extending curved surface against which said corrugated tube can be clamped.

21. A method of installing a fitting assembly for a corrugated tube, said method comprising the steps of: providing a fitting assembly for said corrugated tube comprising a body having first connecting means, a first bore, a first shoulder, and a second shoulder; wherein said first bore transitions to a reduced cross section at said first shoulder, and wherein said reduced cross section transitions to a further reduced cross section at said second shoulder; an insert having a second bore and a transition area of increased outside diameter; locking means having second connecting means disposed therein and an internally directed receiving shoulder; a bushing, a first end thereof having an inwardly projecting protrusion for engagement with a trough disposed on an external surface of said corrugated tube; wherein an opposing end of said bushing seats on said receiving shoulder; sliding said locking means onto said corrugated tube, sliding said bushing onto said corrugated tube, positioning said protrusion into said trough, abutting said insert against said second shoulder to sealingly engage said insert with said body, sliding said locking means, said bushing, and said corrugated tube over said insert towards said first shoulder; and engaging said first and second connecting means to removably secure said bushing, an end of said corrugated tube, and at least a portion of said insert within said body and said locking means, to clamp a circumferential section of said corrugated tube between said transition area and said protrusion and to seal an internal surface of said circumferential section with said transition area.