IES20030662A2 - Push-fit pipe coupling - Google Patents

Abstract

A pipe coupling device is provided in the form of a body having a passage having at least one open end to recieve a pipe, a sealing member disposed in the passage to sealingly engage the pipe and an annular ring also disposed therein. The annular ring has inwardly directed teeth to contact and grip the pipe when the pipe moves past said teeth. The device also includes a release member movable along the passage from a first position in which the teeth are free to grip the pipe to a second position in which the teeth are moved by the release member away from the pipe to thereby enable the pipe to be removed from the device, wherein the release member does not extend past the open end of the passage. This prevents the release member from being accidentally depressed when the coupling is moved past a projection/ A tool is also provided to quickly and easily release a pipe by depressing the release ring. <Figures 3A & 3B>

Description

Technical Field This invention relates to pipe coupling devices of the push-fit type.

Background Art Typically, such devices enable two or more pipes to be coupled in sealing engagement simply by pushing the pipes into receiving bores in the device. A gripping member such as a ring having angled teeth allows the pipe to enter the coupling device with little resistance, but prevents the pipe from being puled out of the device. A release member is typically provided to disengage the gripping member from the device and to enable the pipe to be withdrawn.

The release member is often a depressible annular member through which the pipe enters the device and which has a flange allowing a person to depress the release member into the body of the device and thereby to withdraw the tube. A problem with such devices is that when a length of coupled piping is being moved it is often dragged along a floor or pulled through a tight space. In such cases the flange can catch on projections past which it is being pulled causing the release member to be depressed and the pipe to be released. If the pipe contains a pressurised fluid this can cause expensive damage to the surrounding area . ΙΕ Β ί 0 6 61 Disclosure of the Invention The invention provides a pipe coupling device comprising a body having a passage defining a longitudinal axis with at least one open end to receive a pipe to be coupled thereto, the passage having a sealing member disposed therein to sealingly engage said pipe and an annular ring also disposed therein, the annular ring having inwardly directed teeth angled in the direction away from said open end to contact and grip said pipe when the pipe moves past said teeth, and further comprising a release member movable along said axis from a first position in which the teeth are free to grip said pipe to a second position in which the teeth are moved by the release member away from said pipe to thereby enable the pipe to be removed from the device, wherein said release member does not extend past the open end of the passage.

Preferably, the release member is in the form of a generally annular cylindrical member having a first end flush with said open end of said passage.

Further, preferably, the release member has a second end with a tapered external surface to assist in engaging said angled teeth.

The invention also provides a tool for releasing a pipe from a pipe coupling device, the tool comprising a part-cylindrical body member having a generally Cshaped cross-section to allow a pipe to be introduced laterally therein the body member including an outer CIE U4 0662 shaped cylindrical portion which is adapted to fit over and receive said pipe coupling device internally and an inner C-shaped cylindrical portion terminating at an end surface which is adapted to engage and depress a release member of said pipe coupling device when the device is received in said outer C-shaped cylindrical portion and the tool is pushed against the pipe coupling device.

Preferably, the tool further comprises one or more surfaces extending transversely from the body member to assist a user in depressing the tool against a pipe coupling device.

Further, preferably, the inner portion is shorter than the outer portion, whereby the pipe coupling device is received securely in the outer portion of the tool before the end surface of the inner portion meets the release member.

Preferably, the inner and outer portions are connected by a stop surface and the distance between the stop surface and the end surface of the inner portion is adapted to enable the release member of a pipe coupling device to be depressed sufficiently to release a pipe therefrom.

Brief Description of Drawings The invention will now be further illustrated by the following description of embodiments thereof, given by IE 0306 62 way of example only with reference to the accompanying drawings, in which: Fig. 1 shows a brass body for a pipe coupling device after manufacturing; Fig. 2 shows the body of Fig. 1 when it has been processed to retain components therein; Fig. 3A is an exploded elevation of the components at one end of a pipe coupling device; Fig. 3B is a part-sectional side view of the assembled components at one end of a pipe coupling device .

Fig. 4 is a sectional s ide view of an outer sleeve shown in Figs. 3A and 3B; Fig. 5 is a sectional s ide view of a release ! ring shown in Figs. 3A and 3B; Fig. 6 is a sectional side view of an inner sleeve shown in Figs. 3A and 3B; Fig. 7 is a combined side elevation . and end plan view of a grab ring shown in Figs. 3Ά and 3B; Fig. 8 is an end plan view of an 0-ring shown in Figs. 3A and 3B; Fig. 9 is a side elevation of a tool for use with a pipe coupling device; Fig. 10 is a bottom plan view of the tool of Fig. 9; IE 0 5 0 8 6 2 Fig. 11 is a cross-sectional elevation of the tool of Fig. 9, taken at right angles to the view shown in Fig. 9; and Fig. 12 is a cross-sectional elevation of the tool of Fig. 9, taken from the same angle as the view shown in Fig. 9.

Detailed Description of Preferred Embodiment A brass body 10 for a pipe coupling device of the pushfit type is shown in Fig. 1, in its initial state after manufacturing. The interior of the body 10 includes an inner wall section 12 whose internal diameter is fractionally larger than the pipe sections (not shown) to be coupled by the device, so that two pipe end sections can be introduced into the device, each from a respective end 16,18 of the device, without substantial frictional resistance. The pipe end sections fit within the inner wall section 12 to each abut against a stop ring 14 provided on the inner wall section 12.

The internal diameter of the device is stepped outward at two points moving from the stop ring 14 to the respective ends 16, 18, so that adjacent to each half of the inner wall section 12 is a middle wall section 20 of greater diameter than the inner wall section 12; and adjacent each middle wall section 20 is an outer wall· section 22 of again greater diameter.

The middle wall section and outer wall section are adapted to retain the components (to be described below) which lock the pipe ends in place once inserted. it ud 0662 As shown in Fig. 2, in order to hold the components (not shown) within the body 10, the lip 24 of the body at each end is bent inwards to point towards the centre line 26 of the body 10.

The assembly of components which are held in the body are shown in exploded view in Fig. 3A and assembled together in Fig. 3B. These components are also shown individually in Figs. 4-8 and include: an outer sleeve 28 (Fig. 4), release ring 30 (Fig. 5), inner sleeve 32 (Fig. 6), stainless steel grab ring 34 (Fig. 7), and rubber O-ring 36 (Fig. 8) .

The rubber O-ring 36 (see Fig. 3B) forms a seal by compression against the outer surface of a pipe end (not shown) inserted into the body 10 to abut against the stop ring 14. The inner sleeve 32 made of plastic confines the rubber O-ring in place within the middle wall section 20 where it is afforded a small degree of axial movement to prevent pinching of the O-ring as the pipe is inserted and removed (i.e. the O-ring rolls slightly in the axial direction as the pipe end moves past it). The O-ring and inner sleeve would permit a pipe end to be freely inserted and removed with a small degree of frictional resistance were the grab ring not present.

The grab ring 34 comprises a stainless steel ring 38 (see Fig. 7) having a plurality of inwardly directed resilient teeth 40 arranged on the inner circumference. The teeth are angled towards the stop ring 14 when the IE 03 06 β 2 grab ring is assembled in the device, such that they permit a pipe surface to slide into the device but bite into the surface of the pipe when a force is exerted to remove the pipe from the device. Indeed as the force exerted to remove the pipe increases, the retaining force exerted by the teeth against the surface of the pipe also increases, and only a sufficient force to cause breakage or failure of the teeth would allow the pipe to be removed.

The grab ring is locked in position between the inner and outer sleeves 32,28 which trap the stainless steel ring 40 between them. The outer sleeve is itself held in position by the inwardly directed lip 24 of the brass body which is bent inward after the components are assembled.

The release ring 30 is retained inside the outer sleeve 28.by a flange 42 which has a greater diameter than a stepped surface 44 (see Figs. 4 and 5) of the outer sleeve. A frusto-conical surface 46 on the release ring 30 is adapted to displace the teeth 40 of the grab ring 34 when the release ring 30 is depressed into the brass body. To remove a pipe which is locked into the body by the grab ring, therefore, a tool 48 (Fig. 9) is provided to depress the release ring 30.

The tool 48 has a curved surface 50 which is matched to the outer diameter of the pipe and terminates at an acting end 52 which is placed in abutting relationship against the visible end surface 54 (Fig. 3B) of the IE 05 0662 release ring 30. A flange 54 is provided to enable a user to press the tool 48 along the pipe surface and a short distance into the body 10 causing the release ring to move inwardly into the body forcing the teeth 40 away from the pipe surface. This allows the pipe to be pulled out of the body.

F. R. Kelly & Co.

Agents for the Applicants

Claims (5)

Claims:

1. Ά pipe coupling device comprising a body having a passage defining a longitudinal axis with at least one open end to receive a pipe to be coupled thereto, the passage having a sealing member disposed therein to sealingly engage said pipe and an annular ring also disposed therein, the annular ring having inwardly directed teeth to contact and grip a pipe when the pipe moves past said teeth, and further comprising a release member movable along said axis from a first position in which the teeth are free to grip said pipe to a second position in which the teeth are moved by the release member away from said pipe to thereby enable the pipe to be removed from the device, wherein said release member does not extend past the open end of the passage.

2. Ά device as claimed in claim 1, wherein the release member is in the form of a generally annular cylindrical member having a first end flush with said open end of said passage, and optionally, the release member has a second end with a tapered external surface to assist in engaging said angled teeth.

3. A tool for releasing a pipe from a pipe coupling device, the tool comprising a part-cylindrical body member having a generally C-shaped cross-section to allow a pipe to be introduced laterally therein the body member including an outer C-shaped cylindrical portion which is adapted to fit over and receive said IE 04 0661 pipe coupling device internally and an inner C-shaped cylindrical portion terminating at an end surface which is adapted to engage and depress a release member of said pipe coupling device when the device is received 5 in said outer C-shaped cylindrical portion and the tool is pushed against the pipe coupling device.

4. A tool as claimed in claim 3, wherein the inner portion is shorter than the outer portion, 10 whereby the pipe coupling device is received securely in the outer portion of the tool before the end surface of the inner portion meets the release member.

5. A tool as claimed in claim 3 or 4, wherein the 15 inner and outer portions are connected by a stop surface and the distance between the stop surface and the end surface of the inner portion is adapted to enable the release member of a pipe coupling device to be depressed sufficiently to release a pipe therefrom.