CA2021480A1

CA2021480A1 - Quick-acting coupling

Info

Publication number: CA2021480A1
Application number: CA002021480A
Authority: CA
Inventors: Lionel Calmettes
Original assignee: Individual
Current assignee: Caillau SAS
Priority date: 1989-07-28
Filing date: 1990-07-18
Publication date: 1991-01-29
Also published as: ATE83545T1; KR910003306A; EP0410842A1; JPH0379813A; KR0163043B1; ES2037534T3; EP0410842B1; GR3006978T3; FR2650365A1; FR2650365B1; DE69000594D1; DE69000594T2; DK0410842T3; BR9003638A

Abstract

ABSTRACT OF THE DISCLOSURE

A quick-acting coupling for coupling together two pipes, ducts, or the like, the coupling comprising a tubular member suitable for being fixed to the end of a first pipe and suitable for receiving a rigid tubular endpiece connected to a second pipe; the and sealing means being constituted by an O-ring slidably mounted in a cylindrical portion of the tubular member. The O-ring is suitable for being subjected to the action of a compression spring bearing against abutment inside the tubular member and urging the O-ring away from the first pipe such that co-operation between the axial retention means of the tubular member and the complementary members linked to the endpiece hold the spring in the compressed state.

Description

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A QUICK-ACTING COUPLING
The present invention relates in general terms to devices intended for coupling together two pipes, and particularly to devices of this nature referred to below as "quick-acting couplings".
BACKGROUND OF THE INVENTION
Various types of ~uick-acting coupling are already known, such as described, in particular, in patent applications DE-A-2 016 850 and FR-A-2 171 456, and also in US patent US-A-2 750 209. They essentially comprise a tubular member suitable for fixing to the end of a first pipe and suitable for receiving the rigid end of a second pipe or a rigid endpiece connected thereto.
In general, the tubular member includes both sealing means for co-operating with the rigid endpiece and axial retention means for co-operating with complementary members linked to the endpiece.
US patent US-A-3 503 637 describes a quick-acting coupling in which the sealing means include a flexible annular ring sliding in a cylindrical portion of the tubular member that is intended to receive the free end of the endpiece. A
compression spring coated in a flexible material such as rubber is disposed in the cylindrical portion of the tubular member between the annular ring and an axial abutment linked to the tubular member. This spring is kept compressed by the end of the endpiece after the coupling has been assembled.
However, it has been observed in prior couplings that the sealing means require precautions to be taken during the manufacture of various items that are required to co-operate with one another, and that these precautions are often incompatible with mass production, in particular because of the high cost prices they give rise to.
The present invention provides improvements to the sealing means required for using quick-acting couplings of the type in question and makes it possible to eliminate the drawbacks of prior sealing means.

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SUMMARY OF THE INVENTION
The present invention provides a quick-acting coupling for coupling together two pipes, ducts, or the like, the coupling comprising a tubular member suitable for being fixed to the end of a first pipe and suitable for receiving a rigid tubular endpiece connected to a second pipe, the tubular member comprising both axial retention means co-operating with complementary members linked to the endpiece and sealing means constituted by an 0-ring slidably mounted in a cylindrical portion of the tubular member, said O-ring being suitable for being subjected to the action of a compression spring bearing against an abutment inside the tubular member and urging the O-ring away from the first pipe such that co-operation between the axial retention means of the tubular member and the complementary members linked to the endpiece hold said spring in the compressed state, wherein a moving circular abutment is slidably mounted in the cylindrical portion of the tubular member between the 0-ring and the compression spring, and wherein the 0-ring engaging face of at least one of the moving abutment and the end of the endpiece is chamfered.
By means of these dispositions, the coupling between the two pipes is sealed merely by pressing the 0-ring firstly against the cylindrical portion of the tubular member and secondly against both the free end of the rigid endpiece and the facing face of the moving abutment, against the action of the compression spring.
The advantages of this way of making the sealing means for a coupling also include making it possible to improve the axial retaining means for holding the rigid endpiece in place inside the tubular member. More precisely, it is possible to make use of the axial force due to the compression spring for locking said retention means and for unlocking them easily and without using any tool. In addition, as explained below, it is possible to provide the quick-acting coupling with members for indexing the tubular member and the end~iece, thereby enabling assembly of the coupling to be automated.

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BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the invention is described by way of example with reference to the accompanying drawings, in which:
Figure 1 comprises top and bottom portions constituting two half-views in axial section through a rapid-acting coupling of the invention prior to the two pipes being connected together;
Figure 2 is a view analogous to Figure 1 after connection;
and Figure 3 is a perspective view of a portion of the facing ends of the tubular member and of the endpiece prior to connection.
DETAILED DESCRIPTION
With reference to the drawings, the left of Figure 1 shows a pipe A whose end is mounted on a tubular member given a general reference 1. This is done as taught in French patent application No. 89 02525, and the tubular member 1 comprises a first, preferably metal, element la having a cylindrical inside portion whose righthand end is crimped in a ring lb. A sleeve lc, preferably also made of metal, grips the pipe A and is retained axially by at least one hook ld co-operating with a corresponding abutment le formed in the ring lb.
The tubular member 1 is intended to receive the end 2a of a rigid tubular endpiece 2 having a radial flange 2b. The endpiece 2 is connected by an appropriate means to a second pipe (not shown) or may itself constitute the end of a rigid tube.
It should be observed at this point that the outside diameter 2a of the endpiece is close to the inside diameter of the cylindrical portion la of the tubular member 1, said inside diameter itself being close to that of the ring lb of the tubular portion. However, it may be advantageous, for reasons that appear below, for the inside surface of the ring lb to include circular beading lf pro~ecting a short distance inwards from the ring.
The inside end of the element la of the tubular member includes a rim lg constituting an axial abutment for a 2 ~

compression spring 3. In Figure 1, the spring is relaxed and its righthand end rests against a moving circular abutment 4 slidably mounted inside the element la. An O-ring 5 of rubber or other suitable material is also slidably mounted inside the cylindrical element la to the right of the abutment 4, and it is held inside the cylindrical element la by the beading lf constituting an abutment.
The sleeve lc of the tubular member 1 extends beyond the terminal face of the ring lb and includes at least one tab lh (clearly visible in Figure 3) extending axially from the end of the tubular member towards the pipe A. In the free state this tab is directed towards the inside of the extension of the tubular member 1 constituted by the sleeve lc.
At least one L-shaped recess 2c (more clearly visible in Figure 3) is formed on the outside surface of the flange 2b of the endpiece to correspond with the, or each, tab lh of the tubular member. One of the limbs of the L-shape extends axially and the depth of the recess is preferably constant therein, as can be seen in Figure 1. In contrast, the transverse limb of the recess (and in the example shown there are two such transverse limbs so the recess 2c is T-shaped) has a bottom surface which meets the outside surface of the flange at the end of the limb, which bottom surface may possibly slope.
In addition, the extension of the tubular member 1 constltuted by the sleeve lc advantageously includes a second tab lj also extending axially, but away from the tube A, while still projecting towards the inside of the tubular member.
The tab lj is clearly visible in Figure 3, where it is shown adjacent to the tab lh in order to improve understanding, and in contrast to the configuration suggested by Figure 1.
The relative angular position of the tabs lh and lj is not important so long as the requirements mentioned below are satisfied.
The outside surface of the flange 2b corresponding to the tab 1; is provided with a recess ld which extends a~ially and which opens out into the transverse face 2e of the flange adjacent to the end 2a of the endpiece. The bottom of the ~2~ 3~

recess 2d preferably slopes smoothly, with its end furthest from the face 2e running into -the outside surface of the flange. However, this end of the recess 2d could be constituted by a transverse limb analogous to that of the recess 2c with the bottom surface of the transverse limb also running into the outside surface of the flange.
A coupling o the invention is implemented as follows.
It is assumed that the tubular member 1 and its pipe A are stationary with the endpiece 2 being displaced in the direction of arrow F. The end 2a of the endpiece is initially guided by the ring lb of the tubular member, and is then accurately centered by its beading lf. The preferably chamfered leading edge 2f of the endpiece bears against the O-xing 5 which it pushes back against the action of the compression spring 3.
The circular abutment 4 is also preferably chamfered so that as soon as the compression spring 3 begins to be compressed, the 0-ring 5 is imprisoned in a housing of trapezium-shaped section. As a result, it is pressed appropriately both against the inside surface of the cylindrical portion la of the tubular member and also against the leading edge 2f of the endpiece, thereby providing good sealing between these two parts.
Continuing displacement of the endpiece 2 along arrow F
initially causes the free end of the tab lj to enter recess 2d (providing the endpiece and the tubular member are appropriately disposed angularly relative to each other). In other words, the tab 1; and the recess 2d constitute complementary indexing means which are very useful for automating coupling assembly.
The tab lh is slightly deformed to slide over the outside surface of the flange 2b.
Assuming, naturally, that the angular separation between the tabs lh and 1~ corresponds to the separation between the recesses 2c and 2d, continuing displacement in the direction of arrow F and as guided by co-operation between the tab 1; and the recess 2d will cause the tab lh to drop into the recess 2c.
The quick-acting coupling is thus locked, with the free end of the tab lh being imprisoned both circumferentially and axially 2 ~ 2 ~

by the end of the axial limb of the recess 2c while the spring 3 keeps these parts permanently locked together.
It should be observed here that the length of the end 2a of the endpiece must be sufficient to enable the spring 3 to be 5 compressed while naturally being shorter than the length of the cylindrical portion of the tubular member between its rim lg and the beading lf. Also, when in the locked position as shown in Figure 2, a gap d exists between the face 2e of the flange and the facing face of the ring lb of the tubular member. The dimensions of the various components of the coupling are designed so that width of the gap d is not less than the dis-tance _' between the axial end of the recess 2c adjacent to the face 2e and the beginning of its transverse limb (Figure 1).
By virtue of this disposition, the coupling is easily unlocked without using a tool. All that is required is for the tubular member and the endpiece to be moved towards each other axially until the flange 2b comes into abutment against the ring lb. It is then possible to rotate the endpiece relative to the tubular member, thereby causing the tab lh to escape from its recess 2c via the transverse limb thereof. The tab lj does not prevent this rotation taking place since it is itself practically clear of its recess 2d at the end of the locking operation applied to the coupling. The tubular member and the endpiece can then be separated from each other axially.

Claims

1/ A quick-acting coupling for coupling together two pipes, ducts, or the like, the coupling comprising a tubular member suitable for being fixed to the end of a first pipe and suitable for receiving a rigid tubular endpiece connected to a second pipe, the tubular member comprising both axial retention means co-operating with complementary members linked to the endpiece and sealing means constituted by an O-ring slidably mounted in a cylindrical portion of the tubular member, said O-ring being suitable for being subjected to the action of a compression spring bearing against an abutment inside the tubular member and urging the O-ring away from the first pipe such that co-operation between the axial retention means of the tubular member and the complementary members linked to the endpiece hold said spring in the compressed state, wherein a moving circular abutment is slidably mounted in the cylindrical portion of the tubular member between the O-ring and the compression spring, and wherein the O-ring engaging face of at least one of the moving abutment and the end of the endpiece is chamfered.

2/ A quick-acting coupling according to claim 1, wherein the rigid tubular endpiece includes a radial flange at a distance from its free end which is less than the length of the cylindrical portion of the tubular member, the outside face of said radial flange including at least one L-shaped recess having an axially directed limb which is closed and a transversely extending limb whose end meets the outside surface of the flange, while the tubular member presents at least one resilient tab disposed beyond the cylindrical portion thereof and extending axially towards the first pipe and projecting towards the inside of the tubular member.

3/ A quick-acting coupling according to claim 2, wherein the outside face of the flange of the endpiece includes a second recess extending axially opening out at one end into the transverse face of the flange adjacent to the free end of the endpiece and running into the outside surface of the flange at its opposite end, with the tubular member including a resilient tab beyond its cylindrical portion which extends axially away from the first pipe and projects towards the inside of the tubular member.