Pipe connection fitting

Abstract

A connection fitting (10) for a pipe, including a tubular body (12), an O-ring (14) mountable on outer side of tubular body (12), a substantially tubular collet (16) having a first end and a second end and having a memory, a substantially annular and resilient grab ring (20) for gripping the outer side of a pipe inserted into the collet (16), a substantially tubular spacer ring (22) locatable on the free side of the grab ring (20), a collet retainer (18), and a tubular protection ring (24) locatable within the spacer ring (22), wherein when the collet retainer (18) engages with the collet (16) and causes the collet (16) to lock onto the tubular body (12) apertures (66) in the collet retainer (18) permit portions of the protection ring (24) to be seen after connection of a pipe to the connection fitting (10) is completed.

Claims

1. A connection fitting for a tube or pipe, comprising: a) a tubular body having a first end, a second end, and a bore which extends from the first end towards the second end, the tubular body having an outer surface with a circumferential channel and a collet engaging member, the tubular body being receivable within the tube or pipe; b) an O-ring mounted in the circumferential channel, the O-ring being adapted to enter into a sealing relationship with an inner surface of the tube or pipe; c) a substantially tubular, flexible and resilient collet having a first end and a second end, the second end of the collet operable to engage the collet engaging member to secure the collet to the tubular body; d) a substantially annular and resilient grab ring for gripping an outer surface of the tube or pipe, the grab ring being mounted adjacent the first end of the collet; e) a substantially tubular spacer ring mounted adjacent the grab ring; f) a collet retainer operable to engage the collet and thereby lock the collet to the tubular body, the collet retainer operable to maintain the grab ring and the spacer ring adjacent the first end of the collet; and g) a tubular protection ring mounted within the spacer ring, the protection ring having a chamfered second end to assist in the insertion of the tube or pipe into the connection fitting and onto the tubular body.

2. A connection fitting as claimed in claim 1, wherein the outer surface of the tubular body, inner and outer surfaces of the collet, and an inner surface of the collet retainer are circular in cross-section.

3. A connection fitting as claimed in claim 1, wherein the outer surface of the tubular body, inner and outer surfaces of the collet, and an inner surface of the collet retainer are polygonal in cross-section.

4. A connection fitting as claimed in claim 1 further comprising apertures in the collet retainer, wherein portions of the protection ring can be seen through the apertures after connection of the tube or pipe to the connection fitting is completed.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) In order that the invention may be more clearly understood a preferred embodiment is hereinafter described and shown in the drawings in which:

(2) FIG. 1 is an exploded view of a preferred embodiment of the invention;

(3) FIG. 2 is a perspective view of an integral pair of tubular bodies according to a preferred embodiment of the invention;

(4) FIG. 3 is a view from one end of the body shown in FIG. 2;

(5) FIG. 4 is a longitudinal cross-section along line A-A of FIG. 3;

(6) FIG. 5 is a perspective view from the distal end of a collet according to a preferred embodiment of the invention;

(7) FIG. 6 is a side view of the collet shown in FIG. 5 with the distal end being on the right;

(8) FIG. 7 is a view from the distal end of the collet shown in FIG. 5;

(9) FIG. 8 is a view of the proximal end of the collet shown in FIG. 5;

(10) FIG. 9 is a longitudinal cross-section along line A-A of FIG. 8;

(11) FIG. 10 is a perspective view from the proximal end of the collet retainer according to a preferred embodiment of the invention;

(12) FIG. 11 is a side view of the collect retainer shown in FIG. 10 the distal end being on the right;

(13) FIG. 12 is a view from the proximal end of the collet retainer shown in FIG. 10;

(14) FIG. 13 is a longitudinal cross-section along line A-A of FIG. 12;

(15) FIG. 14 is a perspective view from the distal end of a spacer ring according to a preferred embodiment of the invention;

(16) FIG. 15 is a view from the distal end of the spacer ring shown in FIG. 14;

(17) FIG. 16 is a longitudinal cross-section view along line A-A of FIG. 15;

(18) FIG. 17 is a perspective view from the proximal side of a grab ring according to a preferred embodiment of the invention;

(19) FIG. 18 is an end view from the proximal side of the grab ring shown in FIG. 17;

(20) FIG. 19 is a side sectional view of the grab ring shown in FIG. 18;

(21) FIG. 20 is a perspective view from the distal end of a protection ring according to a preferred embodiment of the present invention;

(22) FIG. 21 is a view from the distal end of the protection ring shown in FIG. 20;

(23) FIG. 22 is a sectional view along line A-A of FIG. 21;

(24) FIG. 23 is a perspective view of a pair of assembled connection fittings prior to connection of the left hand connection fitting to a pipe or tube.

(25) FIG. 24 is a longitudinal sectional view through the assembled pair of connection fittings of FIG. 23;

(26) FIG. 25 is a longitudinal sectional view through the assembled pair of connection fittings during the process of connecting a pipe or tube to the left hand connection fitting;

(27) FIG. 26 is a longitudinal sectional view through the assembled pair of connection fittings at the completion of connection of a pipe or tube to the left hand connection fitting.

DESCRIPTION OF PREFERRED EMBODIMENT

(28) In the drawings the numeral 10 designates generally a pair of connection fittings according to a preferred embodiment of the invention, one of the connection fittings 10a being shown in the assembled form and the other 10b being shown in an exploded view. Here, the connection fittings 10a and 10b are integrated to form an in-line joining means. In the following description, comments will be limited to that part of the pair of connection fittings shown in the exploded view in FIG. 1, i.e., 10b.

(29) In the exploded view the configurational relationship between the components of the preferred embodiment connection fitting can be seen. The terms proximal, and distal, in the above identification of the drawings and in the following description is used to indicate those ends of the components which are, respectively, closer to the mid-point of the pair of connection fittings 10, and further from the mid-point of the pair of connection fittings 10.

(30) Tubular body 12, forming part of connection fitting 10b, is composed of a plastics material and has a uniform bore 26, the distal end 28 of which is chamfered 30. Adjacent the mid-point 32 of the integral pair of tubular bodies, i.e., at the proximal end of tubular body 12, there is provided, on the outer side 38 of tubular body 12, a collet-engaging channel 34 on the distal side of which is disposed a ramp 36. Both collet-engaging channel and ramp 36 circumscribe tubular body 12. Disposed on the outer side 38 and toward the distal end of tubular body 12 is an O-ring-engaging channel 40, which circumscribes the outer side 38.

(31) The O-ring 14 is a typical O-ring, dimensioned to be engaged and restrained from movement by the O-ring-engaging channel 40. The distal end of the outer side 38 of the tubular body 12 is chamfered 30.

(32) The collet 16 is comprised of spring steel. It is generally cylindrical and is provided with four slots 44 opening at the proximal end and an additional four slots 45 opening at the distal end, and four tabs 46 evenly spaced around the circumference. At the proximal end is provided an external flange 48 and an internally directed flange 49, both intersected by the proximally directed slots 44. The flange 48 is chamfered 50 on its proximal side. The internal wall 52 of the collet is chamfered 54 at its distal end 56.

(33) The collet retainer 18 is also generally cylindrical and is composed of stainless steel. The distal end 58 is chamfered 60 into an opening 62 with a slightly narrower diameter than the bore 64 of the main part of the collet retainer 18. Four slots 66 are disposed circumferentially at even intervals around the body of the retainer 18.

(34) Grab ring 20 is formed from spring steel and takes the form of a substantially angular ring 68 from which depends a plurality of radially inwardly extending teeth 70. The teeth 70 are spaced equal distantly around the inner edge of the ring 68. The grab ring 20 is initially formed as a flat blank. Then the teeth 70 are pushed out of the plane of the ring 68 so that they project in a proximal direction at an angle to the plane of the ring 68 with the innermost edges 72 of the teeth 70 being sharp to aid in engagement with the pipe or tube following insertion of the same into the connection fitting and thereby restrain the pipe or tube from being subsequently withdrawn from the connection fitting.

(35) The spacer ring 22 is formed from a plastics material. It is generally cylindrical with a ridge 74 being formed on the outer side 76 towards the proximal opening 78 and chamfers 80, 82 on the outer side 76 and inner side 84 at the distal opening 86. The diameter of the spacer ring 22 is otherwise constant.

(36) The protection ring 24 is also generally cylindrical, although its internal diameter at the proximal end 88 is greater than at the distal end 90, there being a radially inwardly directed annular ramp 92 extending from a point adjacent the distal end 90 to a point adjacent the proximal end 88 of the protection ring 24, thereby defining two inner rings of differing diameters joined by a smooth ramp section. The protection ring is brightly coloured so as to provide a visual indication of the completion of the connection of a pipe to the connection fitting.

(37) The assembly procedure starts with the locating of the O-ring 14 in the O-ring-engaging channel 40 on the tubular body 12. The collet 16 is then pushed on to the tubular body 12 until it engages ramp 36. As pushing continues the collet 16 rides up ramp 36 and the collet 16 expends via the four proximally-opening collet slots 44 until collet 16 reaches the collet-engaging channel 34 on the tubular body 12 whereupon the collet 16 ceases to expand and the internally directed flange 49 at the proximal end of collet 16 engages with, and is located in, the collet-engaging channel 34.

(38) Spacer ring 22 and grab ring 20 are placed inside collet retainer 18, grab ring 20 being located proximally in relation to spacer ring 22. The resulting collet retainer assembly is then located onto the collet 16 and the bore 64 of the collet retainer 18 encompasses the outer side of collet 16. As a small amount of force is applied to push the collet retainer 18 onto the collet 16 the collet 16 compresses via the four distally-opening slots 45. Tabs 46 on the collect 16 are provided with ramps 47 (as can be seen in FIGS. 5, 6 and 9) which assist in this procedure by making it easier to push the collet retainer assembly onto collet 16. The collet retainer assembly is pushed onto collet 16 until the proximal end of the collet retainer 18 meets external flange 48 provided at the proximal end of collet 16. Keeping the collet 16 stationary, the collet retainer assembly is rotated around the collet 16 until the four collet tabs 46 click into the four collet retainer slots 66. Collet 16 is then allowed to expand and return to its pre-compression state. The collet retainer 18 is now locked onto collet 16 and has also locked collet 16 onto the tubular body 12. Spacer ring 22 and grab ring 20 are now secured inside the collet retainer 18.

(39) The protection ring 24 is pushed into and located within the spacer ring 22 and is pushed proximally with respect to the tubular body 12 until it reaches the grab ring 20 in the collet retainer assembly. The protection ring 24 has the same internal and external diameters as the pipe for which the connection fitting 10b is intended. This allows the grab ring 20 to grab the protection ring 24 and hold it in place until insertion of the pipe. The protection ring 24 also locates onto the tubular body 12 which assists in centering the collet 16, gab ring 20, spacer ring 22 and collet retainer 18 onto the tubular body 12. Further, the protection ring 24, by locating on tubular body 12 and being inside the spacer ring 22, protects the O-ring 14 from contamination by foreign matter prior to pipe insertion. FIG. 24 shows in cross-section an assembled pair of connection fittings 10 prior to pipe insertion.

(40) When a pipe is inserted the pipe 100 pushes on the distal end of the protection ring 24. As the protection ring 24 is moved proximally within the connection fitting it compresses O-ring 14 and permits the pipe 100 to ride more easily over the O-ring 14, without the need to chamfer the open end 102 of the pipe 100. As proximal movement of the protection ring 24 continues, due to further pushing of the pipe 100 into the connection fitting, the protection ring 24 continues to travel proximally until it meets the ramp 36 and can move no further. At this point the pipe has been inserted fully into the connection fitting. With the protection ring 24 being brightly coloured and resting against ramp 36 it becomes visible through the proximally opening slots 44 in the collet 16. This indicates that the pipe has been fully inserted into the connection fitting.

(41) It is to be understood that the invention may embrace many further modifications as would be readily apparent to persons skilled in the art and which would be deemed to reside within the broad scope and ambit of the invention. The preferred embodiment described above is by way of example only and is not to be considered as limiting.

(42) Throughout this specification and the claims which follow, unless the context requires otherwise, the word comprise, and variations such as comprises and comprising, will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

(43) The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that the prior art forms part of the common general knowledge.