This invention relates to a system for connecting one or more tubes using a quick lock connector.
Hollow-tubed systems are used in a variety of applications. For example, Electrical Metallic Tubing (“EMT”) conduit systems include elongate, thin walled, non-threaded tubes that are usually formed of metal. EMT tubes are used to enclose electrical wires therein. Similar systems include Rigid Metal Conduit (“RMC”), Galvanized Rigid Conduit (“GRC”), Intermediate Metal Conduit (“IMC”) and Polyvinyl Chloride (“PVC”) conduit, Armored Cable:AC(BX), Metal Clad Cable:MC and Flexible Metal Cable:FMC. Other materials such as plastic, fiber or fired clay can be used as well.
A typical EMT, RMC, or other conduit system usually includes electrical junction boxes, a plurality of EMT tubes, and other electrical systems that are joined together with fittings to provide a continuous protected chamber for receiving electrical wires and their connections therein. These fittings join the tubes to the junction boxes, and they also are used to join two or more sections of tubes together.
Currently, fittings for joining these elements together have undue limitations. For example, one common fitting includes a connector body with an internally threaded compression nut screwed on to body of a fitting which has external male threads. The end portion of a tube is slidably received within the compression fitting, and a worker must tighten the compression nut to compress a steel gland ring pre-installed between a compression fitting body and compression nut to secure the tube within the fitting. In practice, workers can over-tighten some compression nuts to strip both female and male threads of a compression fitting this usually leave tube not secured or not locked in the position of a compression fitting. Alternatively, the worker can under-tighten the a compression nut to the male threads of a compression fitting, thereby allowing the tube to become disconnected over time and expose the wiring unsecured within the tube.
In some cases, when any exterior threads on a compression fitting body or interior threads on a compression nut are not threaded or machined properly, the exterior threads on the compression fitting body and interior threads on a compression nut will not engage or mate well. This misalignment can cause scraping along the entire compression fitting or a loose connection, thereby allowing the tube to become disconnected over time and expose the wiring unsecured within the tube.
Another common fitting includes a body with a perpendicularly mounted threaded set screw. The end portion of a tube is slidably received within the body of a set screw fitting, and a worker must tighten the set screw to secure the tube within the fitting. In practice, workers can over tighten some set screw placing excessive pressure on a localized portion of the tube. In some cases, this excessive pressure can damage the tube. Over-tightening one or two set screw can strip the female threads in the screw boss. Alternatively, the worker can under-tighten the set screw, thereby allowing the tube to become disconnected over time and expose the wiring secured within the tube.
A typical conduit system can have hundreds of these fittings, all of which require hand tightening of each compression nut and set screw on each fitting. The labor of performing this repetitive task can increase the overall cost of a project.
On the manufacturing side of making millions of pieces of these fittings, all of which require a section of tube cut into a defined length to form each compression nut. After forming a piece of tube into a compression nut, manufacturing workers must tap each nut with internal threads. In addition, each compression nut must be secured to a compression connector or a compression coupling. In addition, each compression connector or coupling body must be also be formed in a similar manner with threads being formed on one end of each connector and two threads being formed on each compression coupling.
Set screw type connectors or couplings require labor to punch holes and tap threads on each screw hole, thereby increasing the cost of production. With millions of set screw fittings, compression fittings including compression nuts currently being manufactured each year and each fitting being large and relatively heavy, the cost of energy used in production and transportation, and other transportation related expenses are high. Moreover, the couplings are usually zinc plated, and their relatively large size necessarily increases the amount of zinc plating used, thereby potentially increasing the adverse effects on the environment.
More recently, efforts have been made to provide a snap-in securing system for joining armored MC, AC (BX) and FMC cables to junction boxes and the like. Examples of these types of systems can be found in U.S. Pat. No. 3,272,539 to R. W. Asbury, Sr.; U.S. Pat. No. 3,858,151 to Paskert; U.S. Pat. No. 6,670,553 to Gretz; and U.S. Pat. No. 6,939,160 to Shemtov, all of the disclosures of which are hereby incorporated by reference.
In general, these fittings include a ferrule with one or more annularly mounted tabs or cantilevered snap clips extending therefrom. The tabs and cantilevered snap clips operably engage a portion of the surface of the armored MC, AC (BX), and FMC cables received therein. While these systems prevent the need for set-screws, they can become loose over time and they provide little alignment guidance to assure that they are properly set when installed.
Thus, despite the known improvements to tubing joining systems, there remains a need to a quick-connecting tube engaging system that assists with proper alignment of each tube and evenly distributes the securing load around the entire circumference of each tube secured thereto.
In addition, there remains a need for a tubing joining system that can provide effective and reliable continuity of electricity from a quick-lock connector to a junction box or from quick lock coupling to two or multiple pieces of tubes throughout the entire tube joining system.
In addition, there remains a need for a tubing joining system that includes a securing fitting that cannot be over-tightened or under-tightened, but rather consistently provides the optimal securing force at each connection, which can save labor, energy, environment friendly at both manufacturing site and final fitting installation site.
An embodiment of the disclosed invention has a hollow-tube connecting system with a connector for securing the hollow tube to a structure or a coupling for securing two hollow tubes together, the connector has a body with a tapered interior edge and opening for receiving the tube therethrough. A locking wedge with a tapered exterior surface is received within the body.
In a disclosed embodiment, the locking wedge may have an opening and a plurality of spaced apart ball bearings inlaid in preformed apertures on the locking wedge for snugly receiving the tube therethrough. Inserting the tube into the wedge urges the plurality of spaced apart ball bearings to engage on the exterior surface of tube and move on the tapered interior edge of the body that makes the tube move inward to the bigger interior diameter of tapper body. When a force is applied urging the tube towards the smaller interior diameter of the tapered body, the resulting reaction force on the tube caused by the engaged plurality of ball bearings on the exterior surface of tube and ball bearings moving toward the smaller diameter of tapper interior surface on the connector body creates a friction force holding the tube in the connector. When the reaction force reaches a defined point, it can be called self-locking point. In the self-locking point, the annular tube is locked inside the locking wedge and connector body.
When an annular tube is inserted into the tapered and circular interior wall of the connector body, a geometric triangle is formed by the ball bearings serving as the medium between the annular tube and tapered interior surface of the connector body. When the tube moves toward the bigger diameter of the tapered connector body, it moves freely, but when it moves toward the smaller diameter of tapered connector body, the increased reaction force created from ball bearings movement on the tapered interior surface of connector body to a smaller diameter locks and holds the tube in place in the connector. On the disclosed quick lock coupling, the same locking system in the connector works the same to lock two pieces of tube on each side of a coupling.
The advantages and features of novelty characterizing aspects of the invention are pointed out with particularity in the appended claims. To gain an improved understanding of the advantages and features of novelty, however, reference may be made to the following descriptive matter and accompanying figures that describe and illustrate various configurations and concepts related to the invention.
The foregoing Summary and the following Detailed Description will be better understood when read in conjunction with the accompanying figures.
A rapid connecting system 40 for connecting tubes 42 to each other and to other structures using a quick lock connector 44 is shown in
A. General Construction
Referring to
The connector 44 may be fabricated with materials suitable for use with a conventional conduit tube such as EMT, RMC, GRC, Rigid, IMC, PVC and armored Cable: AC (BX), Metal Clad Cable: MC and Flexible metal cable: FMC.
Once the end of the tube 42 is secured to the locking wedge 52 and guide ring 60 by the installer simply inserting the end of the tube 42 into the opening 48 in the body 46, the roller bearings inlaid on the mating tapered locking wedge 52 engage the exterior surface of tube 42 and at the same time these roller bearings are against and move on the tapered interior surface 50 of body 46 thereby preventing the tube 42 from being removed backward to the smaller diameter of body 46 and from the connector 44. The body 46 may be connected to a base structure 70 to form a complete quick lock connector and with features for securing the connector 44 to another component 72 (
a. Connector Body with Tapered Interior
As best shown in
The interior surface 50 of the connector body 46 is tapered to get smaller as it approaches the opening 48 and body 46 is tapered to get bigger as it approaches to a base engaging portion 80. The taper angle is preferably between 3 to 25 degrees, inclusive. More preferably, the taper angle is between 8 to 12 degrees, inclusive.
The connector body 46 includes a base engaging portion 80 opposite the opening 48. The base engaging portion 80 includes attachment features for securing the body 46 to the base structure 70 such as by compression, pressing, rolling, riveting or the like. A shoulder 82 may also be provided in the base engaging portion 80 for operably receiving and engaging the guide ring 60 therein and connecting to the base structure 70.
The connector body 46 is formed with substantially rigid materials suitable for the particular type of tubing being used. For example, in cases where the tubing is EMT tubing, the body may be formed with suitable tubing that can work with EMT tube or the like.
b. Tapered Locking Wedge
As best shown in
A plurality of spaced apart bearings 100, such as rigid ball bearings, may be rotatably secured within apertures 102 in the wall 94 of the locking wedge 52 such that the bearings extend inwardly to engage the exterior surface of the tube 42 and move against the interior wall 50 of connector body 46 as it is slid though the opening 92 in the locking wedge 52 and facilitate insertion of the tube 42 and move along with tube 42 through the locking wedge 52 toward guiding ring 60. More preferably, the bearing includes steel balls and each ball is spaced equal distance apart from the other balls along the circumference of the locking wedge wall as best shown in
Referring to
c. Guide Ring
As best shown in
A plurality of spaced apart protrusions 112 or tabs extend from the ring 60 towards the opening 110. The protrusions 112 are angled away from the opening 48 in the connector body 46 so that they allow the tube 42 to be inserted through the ring opening 110 and grasp the tube 42 should it be moved in a perpendicular direction away from the opening in the connector body 46. Preferably at least 4 to 12 protrusions 112 are spaced equal distance around the circumference of the guide ring 60 as shown. By snugging and grasping the exterior surface of tube 42 through a plurality of spaced apart protrusions 112 or tabs extend from the ring 60, it provides excellent continuity of electric and low electric resistance on connector 44 throughout tube 42 to a connected structure 72 (
The outer diameter of the guide ring 60 is sized to be snugly received within the base engaging portion 80 of the connector body 46. Accordingly, the ring opening 110 remains aligned along the longitudinal center line of the connector 44 and the opening 48 in the body 46. The process of inserting an end of a tube through the opening 48 in the body 46, then the opening 92 in the locking wedge and finally the opening 110 in the guide ring 60 necessarily urges the tube 42 into proper alignment along the longitudinal centerline of the connector 44 and finally stop at tube stop 123 (
d. Base Structure
As best shown in
The object engaging portion 122 can be configured to mount to a variety of structures. For example, the object engaging portion 122 can include a threaded element 130 and locking nut 132 for securing the connector 44 through a hole 134 in a conventional electrical junction box 72 (
Alternatively, the object engaging portion 122 can include two or more connector body engaging portions 120 as shown in
It can be appreciated that the tube 42 used need not be substantially straight. For example, the tube 42 can be T-shaped 71 (
e. Threaded Tube Attachment Structure
Referring to
An installer can mount a threaded tube 42′ to a connector 44 by first inserting the annular insert 302 into the connector 44 and then threading the threads 310 of the tube 42′ into the annular insert 302 in the connector 44. Alternatively, the installer can first thread the annular insert 302 onto an end of the threaded tube 42′ and then insert the threaded tube 42′ with the annual insert 302 installed into a connector 44.
f. Exemplar Method of Fabricating Connector Components
An exemplar method of fabricating the components forming the connector using machining is herein described. Other methods such as molding could also be used to form these components.
The connector body 46 is shown being formed from a section of cylindrical tube 46a in
The guide ring 60 may be formed from a substantially planar blank that has been cut in to a predefined shaped, and then pressed to define the guide ring 60 with protrusions 112 as shown and previously described.
B. Use and Operation
Having described the elements of the present invention, their use and function becomes apparent. An installer inserts an end of a hollow tube 42 into the opening 48 in the connector body 46 and pushes the end of the tube 42 into the opening 46. The tube 42 operably engages plurality of spaced apart roller bearings, that are preferably steel spherical balls, on the locking wedge 52, at the same time, roller bearings inlaid in locking wedge 52 engage and move on the tapered interior surface of body 46, tube 42 continue to extend through the opening 92 in the locking wedge and the opening 110 in the guide ring 60. The protrusions 112 in the guide ring 60 hold the ring 60 onto the tube and end of tube 42 finally stops at tube stop 123 formed inside base structure 70. As soon as tube 42 enters tapered connector body 46, which preferably has an 8 to 12 degree tapered interior wall, and locking wedge 52, the steel ball bearings on 52 immediately engages on the exterior surface of tube 42. When steel ball bearings on locking wedge 52 move on the tapered interior surface of body 46, it creates friction force between steel ball bearings and tapered interior wall of body 46, which also creates and increase reaction force on the exterior surface of tube 42 thereby holding the tube 42 in the connector 44.
If a force is inadvertently applied in a direction that would pull the tube 42 out of the connector 44 or to the opening 92 of locking wedge 52 and the opening 48 of tapered connector body 46, the steel ball bearings move on the tapered interior surface of connector body 46 along with tube 42 backward to the smaller diameter of tapered connector body 46. The resulting friction force created by this action causes a reaction force to compress against the exterior surface of tube 42, when steel ball bearings move to the self-locking position, or when the reaction force reaches a point to have enough compression against the exterior surface of tube 42, the annular tube 42 thereby is locked in the position inside of the connector 44. Whenever a force is applied in this direction, the smaller diameter of tapered connector body 46 with tapered interior surface seeks to pull tube 42 out of connector 44, but the plurality of steel ball bearing lock tube 42 inside locking wedge 52.
An installer may easily insert the end of a tube 42 into a connector 44, with the guide ring 60 and tapered locking wedge 52. When the tube 42 moves inwardly to a bigger diameter on the tapered interior surface of connector body 46, steel ball bearings inlaid in the apertures of locking wedge 52 apply a holding force that is distributed throughout the circumference of the tube 42 thereby holding the tube 42 in place. When tube 42 moves backward to a smaller diameter of tapered interior surface of connector body 46, the steel ball bearings applying locking force in locking wedge 52 that locks tube 42 in the place. It can be appreciated that the connectors 44, tubes 42 and component engaging structures allow a complete quick lock tubing securing systems, such as an electrical conduit system to be completely, quickly, efficiently, cost effectively and easily connected without the need for securing compression nuts and set screws or the like.
One skilled in the relevant art will recognize that numerous variations and modifications may be made to the configurations described above. For example, as shown in
This application claims priority to U.S. provisional patent application Ser. No. 61/906,214, filed on Nov. 19, 2013, the disclosure of which is hereby incorporated by reference.
Number | Name | Date | Kind |
---|---|---|---|
384654 | Wales | Jun 1888 | A |
1592454 | Frederickson | Jul 1926 | A |
1831856 | Fullman | Nov 1931 | A |
2747899 | Wiltse | May 1956 | A |
3285551 | Tschanz | Nov 1966 | A |
3375485 | Donohue | Mar 1968 | A |
3889989 | Legris | Jun 1975 | A |
4350840 | Michaels | Sep 1982 | A |
4508407 | Ball | Apr 1985 | A |
D285048 | Beck | Aug 1986 | S |
D287333 | Knudson | Dec 1986 | S |
4739126 | Gutter | Apr 1988 | A |
D303710 | Neill | Sep 1989 | S |
D305532 | Gallo et al. | Jan 1990 | S |
4919370 | Martin | Apr 1990 | A |
4969845 | Hauchard | Nov 1990 | A |
5051541 | Bawa | Sep 1991 | A |
5117479 | Erdman et al. | May 1992 | A |
D329043 | Rogers | Sep 1992 | S |
5266050 | O'Neil | Nov 1993 | A |
D347467 | Medvick | May 1994 | S |
5529508 | Chiotis | Jun 1996 | A |
5529522 | Huang | Jun 1996 | A |
5536184 | Wright | Jul 1996 | A |
D374862 | Lee | Oct 1996 | S |
5586910 | Del Negro | Dec 1996 | A |
D383053 | Schrader et al. | Sep 1997 | S |
D383378 | Schrader et al. | Sep 1997 | S |
D400670 | Sorkin | Nov 1998 | S |
D412738 | Kuwabara | Aug 1999 | S |
D414462 | Peterson et al. | Sep 1999 | S |
D417138 | Sauber | Nov 1999 | S |
D419860 | Persson | Feb 2000 | S |
6043432 | Gretz | Mar 2000 | A |
D424919 | Sato et al. | May 2000 | S |
D435830 | Cheng | Jan 2001 | S |
D453816 | Sato et al. | Feb 2002 | S |
6348657 | Haslock | Feb 2002 | B1 |
6414243 | Korinek | Jul 2002 | B1 |
D464409 | Nishio | Oct 2002 | S |
6468100 | Meyer | Oct 2002 | B1 |
6538201 | Gretz | Mar 2003 | B1 |
6548760 | Stout, Jr. | Apr 2003 | B1 |
6583357 | Rubenstein | Jun 2003 | B2 |
D483094 | Wilk, Jr. et al. | Dec 2003 | S |
D495404 | Wilk, Jr. et al. | Aug 2004 | S |
D500475 | Noro et al. | Jan 2005 | S |
D504312 | Peacock | Apr 2005 | S |
D517904 | Alkalay | Mar 2006 | S |
D518559 | Østergaard et al. | Apr 2006 | S |
D524427 | Wilk, Jr. et al. | Jul 2006 | S |
7074077 | Sakaguchi | Jul 2006 | B2 |
D529865 | Lapere | Oct 2006 | S |
D530669 | Shing | Oct 2006 | S |
D573537 | Svoboda et al. | Jul 2008 | S |
D574067 | Pampinella et al. | Jul 2008 | S |
D577674 | Long et al. | Sep 2008 | S |
D577795 | Smith et al. | Sep 2008 | S |
D584228 | Strickland | Jan 2009 | S |
D592596 | Kolton | May 2009 | S |
D599289 | Roos | Sep 2009 | S |
D599894 | Price et al. | Sep 2009 | S |
D606494 | Holliday | Dec 2009 | S |
D607547 | Maier et al. | Jan 2010 | S |
D614270 | Green et al. | Apr 2010 | S |
D623142 | Amidon | Sep 2010 | S |
D624019 | Victor | Sep 2010 | S |
D624508 | Amidon | Sep 2010 | S |
7841630 | Auray et al. | Nov 2010 | B1 |
D631848 | Montena et al. | Feb 2011 | S |
7933165 | Thompson | Apr 2011 | B2 |
D637697 | Steiner | May 2011 | S |
D647391 | Barrese | Oct 2011 | S |
D649862 | Arvinte et al. | Dec 2011 | S |
D650052 | Drenth | Dec 2011 | S |
D651696 | Giordano | Jan 2012 | S |
D654150 | Bonhag et al. | Feb 2012 | S |
D665471 | Fossum | Aug 2012 | S |
D676940 | Kluss et al. | Feb 2013 | S |
D678755 | Weidemann et al. | Mar 2013 | S |
D691879 | Bernard | Oct 2013 | S |
8552296 | Joye | Oct 2013 | B2 |
D693774 | Scime | Nov 2013 | S |
D719646 | Melo | Dec 2014 | S |
20020166691 | Yaworski | Nov 2002 | A1 |
20020185862 | Louden | Dec 2002 | A1 |
20030019649 | Rubenstein | Jan 2003 | A1 |
20030094298 | Morrow | May 2003 | A1 |
20040050574 | Wu | Mar 2004 | A1 |
20090218131 | Sheehan | Sep 2009 | A1 |
20120068456 | Smith | Mar 2012 | A1 |
20120129409 | Drew | May 2012 | A1 |
20130020797 | King et al. | Jan 2013 | A1 |
20130087381 | Daughtry | Apr 2013 | A1 |
Number | Date | Country |
---|---|---|
2010106993 | May 2010 | JP |
4537224 | Sep 2010 | JP |
Entry |
---|
Office Action dated Apr. 27 2015 in U.S. Appl. No. 29/482,009. |
“Amico Stainless Steel Cable Glad Connector” May 17, 2012, Amazon.com, cited Apr. 13, 2015 http://www.amazon.com/Amico-tainless-6-0-12-0mm-Connector-Looknut/dp/B00843ULPY. |
Office Action dated Apr. 27, 2015 in U.S. Appl. No. 29/482,009. |
Office Action dated Mar. 26, 2015 in Canadian Design Application No. 158063. |
Office Action dated Jan. 6, 2016 in US Design U.S. Appl. No. 29/482.009. |
Number | Date | Country | |
---|---|---|---|
20150136474 A1 | May 2015 | US |
Number | Date | Country | |
---|---|---|---|
61906214 | Nov 2013 | US |