WO1995000793A1

WO1995000793A1 - Quick-connect tubing coupling

Info

Publication number: WO1995000793A1
Application number: PCT/NO1994/000126
Authority: WO
Inventors: Manfred Schlaupitz; Hans Peter Havdal; Tore Pedersen
Original assignee: Kongsberg Automotive A/S
Priority date: 1993-06-22
Filing date: 1994-06-22
Publication date: 1995-01-05
Also published as: NO932292L; NO932292D0

Abstract

A quick coupling for pressure fluid systems, with a male part (1) which is arranged to be inserted into a female part (2). The female part (2) comprises at least one gripping element (41, 42) which can be releasably secured by a locking member (60), thus preventing the gripping element (41, 42) from moving in the female part's (2) longitudinal direction. The gripping element (41, 42) is provided with at least one radially springing and radially inwardly projecting gripping hook portion (47). This is arranged to be springingly pushed radially outwards by a shoulder portion (30) of the male part (1) when the gripping hook portion (47) passes the shoulder portion (30) during the insertion of the male part (1) into the female part (2), and thereafter to be springingly moved back, thus bringing it into engagement with the male part's shoulder (31). Disconnection of the locking member (60) causes the release of the gripping element (41, 42) from the shoulder portion (30).

Description

Quick-connect tubing coupling

The invention concerns a quick coupling as specified in the introduction to claim 1.

Within the industry increasingly stringent requirements are being introduced for the simple and rapid installation of pipe and hose couplings, and for these couplings to be cheap and reliable.

Thus in car production, e.g., demands are made for the installation of hydraulic couplings without tools, solely by the act of inserting the coupling's male part axially into the female part. In addition the coupling must comprise as few components as possible, but these should be simple and robust and inexpensive to produce. Furthermore it is required that there should be no deformation in the connection between the coupling parts, thus causing it to be impaired when the fluid pressure in the coupling increases. Moreover there is a requirement that the coupling should be able to be dismantled by simple means.

The object of the invention is to provide a rapid coupling of the type mentioned in the introduction whereby the above-mentioned requirements are fulfilled.

The characteristics of the quick coupling according to the invention are indicated by the features in the claims presented.

The invention will now be described in more detail with reference to the drawing which schematically illustrates an embodiment of a quick coupling according to the invention.

- Fig. 1 shows a longitudinal section through an assembled quick coupling where a section of the coupling's female part and the pipe with which the coupling's male part is connected are cut away. - Fig. 2 is a perspective view of a gripping element.

- Fig. 3 shows a section through the gripping element which is illustrated in fig. 2 and along line III-III in this figure.

In a known per se manner the quick coupling comprises a male part 1 with a main piece 3 and a female part 2 with a main piece 4. As indicated in fig. 1 the main piece 3 of the male part has a through-going, axially extending bore 5, through which there extends a pipe 6 of a pressure fluid system (not shown in more detail). The pipe 6 is attached to the main piece 3 by means of a conical sleeve 7 which is passed over the pipe 6 and wedged sealingly between the pipe 6 and the main piece 3 in a correspondingly shaped enlarged portion of the bore 5 of the main piece 3.

Fig. 1 also illustrates that the female part 2 has a through bore 8 with a diameter which corresponds to the internal diameter of the pipe 6, and that the male part's and the female part's bores 5 and 8 respectively are coaxial.

The male part's main piece 3 comprises a cylindrical section 9 which is inserted into a bore 10 of the female part 2 in the illustrated position, in which the male part and the female part are connected. The end section of the pipe 6 has an enlarged portion 11. Between this enlarged portion 11 and the adjacent end section of the main piece 3 there is provided a seal 12, which abuts against the wall of the bore 10 and seals the connection between the main pieces 3,4.

The axially outer, i.e. the free end section of the female part's main piece has a cylindrical, outer surface 20. At the axially inner end of this surface 20 of the female part 2 there is provided a radially inwardly extending, circumferential groove 21.

At the inner end of the male part's main piece 3, i.e. the end which is located above, i.e. opposite the free end of the main piece 3, it has a radially outwardly projecting shoulder portion 30 whose diameter corresponds to the diameter of the cylindrical surface 20 of the female part 2. The shoulder portion 30 has an axially inwardly facing and radially extending shoulder surface 31.

On the outside of the cylindrical surface 20 of the female part there are provided diametrically opposite each other two approximately semi-cylindrical or semi- tubular, preferably mutually identical gripping elements 41,42, which project radially outside and axially past the shoulder portion 30 of the male part, and whose design will be described in more detail with reference to figs. 2 and 3.

At the end of the gripping element which is arranged to be located innermost on the female part 2, hereinafter called the axially inner end of the gripping element, there is provided a radially inwardly projecting bead or shoulder-shaped portion 43, which is arranged to project into the groove 21 of the female part 2 in order thereby to prevent mutual axial movement of the female part 2 and the gripping elements 41,42.

At some distance from the inner end, the axially inner end section of the gripping element is provided with an outwardly projecting, rounded knob 52.

At a distance from the outer end of the gripping element 41,42, by means of through-going slits or slots 44 in the wall of the gripping element, there are provided a number of axially inwardly projecting fingers 45. The finger roots are thus interconnected via a semicircular portion 46. Near the finger tip portion 50 there is provided on the inner wall of each finger a gripping hook portion 47 with an axially and radially inwardly extending surface portion 48, which thus extends obliquely in relation to the coupling's longitudinal axis, and a shoulder surface 49, which extends radially inwards from this surface section's inner termination.

Due to the spring properties of the material of which the gripping element is made, such as plastic, spring steel, etc., and the shape and thickness of the fingers, they are elastically flexible radially inwards and outwards. The diameter of the circular line on which the gripping hook portion's radially inner termina¬ tion or edge is located, is smaller than the diameter of the male part's shoulder portion 30 when the fingers are not influenced by a force which attempts to bend them.

On the outside of the axially inner section of the gripping elements there is passed a sleeve-shaped locking member 60 whose internal diameter approximately corresponds to the external diameter of the gripping elements 41,42 and in whose inner wall there is formed a depression 61 with a shape which is adapted to the shape of the knob 52 of the gripping element. When the gripping elements 41,42 are provided on the female part 2, the knobs 52 are located diametrically opposite each other.

The diameter on which the tops of the knobs are located is slightly larger than the internal diameter of the locking member 60. When the locking member 60 is passed over the gripping elements 41,42 and the female part 2, it therefore becomes slightly deformed when it is forced over the knobs 52, but recovers its original shape when each of these has been located in its own depression 61. In this manner the locking member 60 is safeguarded against inadvertent displace¬ ment on the gripping elements 41,42.

The quick coupling is used in the following manner.

First of all the two gripping elements 41,42 are located on the female part 2, the beads 43 being located in the groove 21. The sleeve-shaped locking member 60 is then passed over the gripping elements 41,42 until the knobs 52 by means of a snap effect are caused to slip into their respective depressions 61. The gripping elements 41,42 are thereby attached to the female part 2 and safeguarded against axial as well as radial movement in relation to the latter. The locking member 60 is similarly secured.

In order to effect the connection, the male part 1 is then inserted into the female part 2, in the course of which the shoulder section 30 is brought into abutment against the oblique surface portion 48, thereby forcing the fingers 45 radially outwards during the continued insertion of the male part 1. When the male part has been inserted into the correct position in the female part, the shoulder surface 49 of the gripping hook portion 47 passes the shoulder surface 31 of the shoulder portion 30, whereupon the fingers 45 springingly return to their unloaded position, and any movement of the male part away from the female part is prevented by the mutual abutment of the shoulder surfaces 31, 49.

When the coupling is disconnected the locking member 60 is pulled axially out¬ wards from the female part 2 and past the gripping elements 41,42. These are then loose and can easily be removed by hand, after which the male part 1 can be pulled out of the female part 2.

By means of the above-mentioned arrangement of the gripping element's fingers 45 a force P which is exerted against them via the male part's shoulder surface 31 will attempt to move the fingers 45 in the direction of the arrow M (fig. 3), i.e. radially inwards about the semicircular end section 46. By this means the fingers will not be swung away from the male part 1 when the fluid pressure in the coupling increases. The abutment of the finger tips against the male part thereby restricts the movement of the fingers radially inwards.

It has been stated in the above that the locking member can have two depressions 61 for snap-like reception of the respective knobs 52. The securing of the locking member and the gripping elements 41,42 relative to each other, which prevents the locking member from being inadvertently moved axially away from the position in which it secures the gripping elements, can of course be implemented in another way, e.g. where the locking member as in a bayonet coupling has two diametrically oppositely located L-shaped slits into which the respective knobs 52 can be introduced. By means of a suitable design of the slit it can be ensured that the locking member cannot be inadvertently turned away from the position in which it secures the gripping elements 41,42.

Claims

PATENT CLAIMS

1. A quick coupling for the interconnection of components of a pressure fluid system, comprising a male part (1) and a female part (2), with tubular main pieces (3,4) which are sealingly and fixedly connected with pipe elements (6) of the system, where the male part's (1) main piece (3) is arranged to be inserted into the female part's (2) main piece (4) in the coupling's longitudinal direction and engaged sealingly in it, and comprises an axially inwardly facing, i.e. away from its free end, shoulder (31), and the female part (2) comprises at least one resilient finger member (45), which, when it is a condition in which it is not influenced by any force, projects axially away from the female part's (2) free end section and radially inwards into the space which is arranged for the recep¬ tion of the male part (1), where, by means of bending out the finger member against the spring force exerted by the latter, a gripping hook portion (47) of the finger member (45) is arranged to be moved radially outwards by means of the male part (1) by introducing it axially into the space, and by means of a return movement of the finger member (45) to engage with the shoulder (31) after the male part (1) has been sealingly completely inserted into the female part (2), c h a r a c t e r i z e d i n that the female part (2) comprises at least one gripping element (41,42) which has at least one gripping hook portion (47), which gripping element (41,42) is arranged to be located on the outside of the female part's (2) main piece (4), and the female part (2) also comprises a locking member (60) for releasable securing of the gripping element (41,42) on this main piece (4) via a second section of the gripping element (41,42).

2. A quick coupling according to claim 1, c h a r a c t e r i z e d i n that the gripping element (41,42) is in the form of a pipe section, which in cross section is in the shape of a circular arc, which does not extend over more than 180°, and that the gripping element (41,42) is arranged to abut against a cylindrical section (20) of the female part's main piece (4) which is adapted to it in shape, the gripping hook portion (47) being provided in one end section of the gripping element (41,42), and its second end section being arranged to be secured on the main piece (4) by means of the locking member.

3. A quick coupling according to claim 2, c h a r a c t e r i z e d i n that the second end section of the gripping element (41,42) has a radially inwardly projecting flange which is arranged to engage with an at least partially circumferential, radially outwardly open groove (21) of the female part's main piece (4).

4. A quick coupling according to claims 2 or 3, characterized in that the locking member (60) is tubular and arranged to enclose the gripping element (41,42) on the female part's main piece (4) and by means of a snap effect to be secured against axial displacement on the gripping element (41,42).