GB2068069A

GB2068069A - Disconnectible pipe couplings

Info

Publication number: GB2068069A
Application number: GB8041072A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-01-30
Filing date: 1980-12-22
Publication date: 1981-08-05
Also published as: SE8000716L; AU6673381A; GB2068069B; JPS5740196A; DE3101079A1; FI70465B; FI70465C; FR2474640A1; FR2474640B1; JPS647276B2; SE428721B; CA1141798A; FI803927L; DE3101079C2; AU534776B2

Abstract

A coupling member 1 includes a valve body (3a, 3b, 3c) which is fixed, and a longitudingally-displaceable sleeve (4) which in a sealing position is designed to seal against the valve body, via a sealing element (7) arranged on the latter. The sealing element (7) is arranged in the valve body in such a way that in the sealing position the sleeve extends past the sealing element. The pressure medium within the valve body acts on the sealing element and thus contributes towards effective mutual sealing between the valve body and the sleeve (4). On insertion of a male coupling member 2 into the coupling member 1 the sleeve 4 is pushed back by engagement between a surface 2a in the member 2 and a shoulder 4c on the sleeve 4. <IMAGE>

Description

SPECIFICATION Coupling member The present invention relates to coupling members of the kind which comprise a valve body, fixed or movably arranged, and a longitudinally-displaceable sleeve which in a sealing position is designed to seal against the valve body via a sealing element arranged on the latter. Hence the invention is aimed at utilisation, inter alia, on "environmental couplings" or non-spill couplings where the said coupling components are, by means of a rapid coupling function, capable of interacting with another coupling member. The connected medium can comprise hydraulic oil.

The method is already known of designing the said environmental couplings as "flat nose couplings", which are characterised in that both coupling members are provided with nose sections with essentially plane frontal surfaces which can easily be wiped dry prior to the coupling members being connected together. In such a non-spill flat nose coupling the said sleeve is incorporated in the form of an inner sleeve which is spring-actuated in one direction, and in its other direction it can be displaced by means of the second coupling component against the said spring action. Here it is important that the sleeve in the position in which it is not affected by the second coupling member can adopt a sealing position by means of the said spring action and possibly pressure from a medium which is present in the coupling member which is thus closed.In this connection the sealing arrangement should be such that the force when the coupling members are joined together does not become excessive. In the known type of flat nose couplings a covering sleeve arrangement is also employed which is displaceable relative to the said sleeve and valve body. The said sealing covering sleeve arrangement exhibits an external surface which forms part of the essentially plane frontal surface of the coupling member.

With the relevant types of couplings it is important to be able to bring about a sealing arrangement for the inner sleeve and the valve body which provides the necessary high standard of sealing, whilst at the same time the components involved are constructed in such a way that manufacturing costs can be kept at a relatively low level.

It is also important that the different portions of the coupling be designed so that dirt and extraneous particles are prevented from entering at the frontal surfaces of the coupling members concerned.

An object of the present invention is to provide an arrangement which, inter alia, solves the abovementioned problem and the main characteristic of the invention is that the valve body is designed with a supporting device which is assigned to the said sleeve, which exhibits a supporting surface which is plane and extends essentially radially, against which the sleeve is designed to rest in the said sealing position. The valve body is furthermore provided with a sealing element so that in the said sealing position the sleeve extends right past the sealing element and together with the valve body and its supporting device forms an essentially closed cham berforthe sealing element.Via a gap which faces away from the supporting device the chamber is connected with a medium pressure, which is sealed off by the coupling member, which is effective on the sealing element and by this means contributes towards effective mutual sealing of the valve body and the sleeve by means of the sealing element.

In further embodiments of the concept of the present invention it is proposed inter alia, to provide a flap, capable of being folded down, and forming part of the valve body, which in the rolled down pdsition fixes the sealing element to the valve body.

The said flap is furthermore so arranged that the sealing element is given a protected position with respect to the medium pressure. Furthermore more comprehensive details are given of the construction of the supporting device and the inner sleeve so as to form a suitable chamber which fundamentally exceeds the volume of the sealing element and arranged in such a way that effective deformation of the sealing element is brought about, which is to some extent pressed directly axially against the radial top surface of the supporting device, and to some extent directly radially against the inner wall of the sleeve, whereby reliable sealing of the essentially radial gap between the valve body and sleeve is achieved.

In connection with the said further embodiments, improvements are also proposed in connection with the design of the inner sleeve and of the valve body which become feasible thanks to the invention. In addition details are given as to how the supporting device is to be arranged in relation to the opposing sections on a further sleeve, in the form of a covering sleeve, which is located outside and capable of movement in relation both to the inner sleeve and the valve body. The latter-mentioned components can in this connection form part of a flat-nosed environmental coupling arranged with rapid coupling function for the two coupling members.

Nevertheless the new coupling can be regarded as being characterised mainly by what is stated in the descriptive portions of the following patent claim 1.

The proposals above provide an effective sealing arrangement with technicalieconomic advantages for, inter alia, the above mentioned types of couplings, the other components of which can Thanks to the present invention - also be given an appropriate and economic design.

Thanks to the new arrangement there is only one gap in the essentially plane frontal surface on the coupling component concerned, which in an excellent manner, also reduces the risk of dirt penetration in the media system. Furthermore the sealing element is given a location which is protected from the said dirt and extraneous particles.

The sealing arrangement functions both at low and high pressure, the latter for example being capable of exceeding 30 Mpa. In the latter case the sealing arrangement and sleeve are so arranged that the pressure of the actual medium affects the sealing element and, by exerting purely axial and radial forces on this, contributes to effective sealing.

Thanks to the proposals above, I avoid the sleeve resting on the supporting device via slanting sealing surfaces which require relatively high manufacturing precision and considerable thickness of the material in the sleeve.

A proposed embodiment of an arrangement which exhibits the characteristics significant of the present invention will be described in the following with simultaneous reference to the attached drawings in which: Figure 1 shows in longitudinal section two quick coupling members designed for hydraulic oil in the de-coupled position, the said quick coupling members forming together a non-spill environmental coupling with essentially plane frontal surfaces on the coupling members.

Figure 2 shows in longitudinal section the coupling members as in Figure 1 in a fully coupled position, whereby coupling together takes place with the aid of automatic coupling components on the coupling members.

Figure 3 shows enlarged and in longitudinal section portions of the frontal section of the first coupling component (female portion) of the coupling members in Figure 1 and 2.

Figure 4 shows in longitudinal section a modified embodiment of the components shown in Figure 3.

Figure 5 shows in longitudinal section one half of the female coupling member in a further modified embodiment, and Figure 6 shows in longitudinal section one half of the female coupling member in an embodiment modified over all the other embodiments.

The coupling as shown in Figure 1 and 2 comprises first coupling member 1 and a second coupling member 2, whereby coupling member 1 comprises a female portion and coupling 2 is a male portion.

The coupling forms a "flat nose coupling" where the respective coupling members are made with an essentially plane frontal surface 1a and 2a respectively.

Couplings of this type are as such assumed to be well known, so that only a brief account will be given here of their fundamental construction and function.

The first coupling member 1 includes a valve body, of the "shank design", which is located firmly and coaxially relevant to the first coupling member inside the first coupling member. An inner sleeve 4 and an outer sleeve or covering sleeve 5 are arranged so that they can be displaced relative to the valve body 3. The outer sleeve 5 is angled at one end and at its other end is subject to spring action by a spiral spring 6 which tries to keep the outer sleeve pressed against the said frontal surface 1 a.

The valve body includes inter alia a valve head 3a which carries a seal 7- and on its first end sections 4a the inner sleeve is designed, when in a sealing position as shown in Figure 1,to interact with the said valve head 3a and the sealing ring 7, so that a sealing function is obtained between the sleeve 4 and the valve head 3 with the aid of the seal. A spring 8, preferably a helical spring, is effective against the other end portions of the sleeve 4, more precisely the end edge 4b, and tries to maintain the inner sleeve in the sealing position. At its upper end sections the inner sleeve carries a further seal 9 which comprises a "back-up" seal of a type which as such is well known. The sleeve 1 is mounted in a first recess 1 b in the first recess 1 b in the first coupling member, whereby the sleeve receives guidance on a first internal wall 1 b' of the said recess.The seal between the sleeve 4 and the said inner wall 1b' is provided by means of the said seal 9. The said first chamber comprises a partial chamber in the first coupling member and is provided with a portion 1c which extends axially inside the first coupling member.

The outer sleeve rests in the second chamber 1 d in the first coupling member, whereby the wall of the chamber is designated 1 d'. The outer surface rests against this inner wall 1 d' and the outer extreme position of the outer sleeve is governed by a lip 5a thereon. The angled portion 5b of the outer sleeve is designed to be capable of interacting with frontal portions of the second coupling member, with the aid of which the outer sleeve is thus capable of insertion in the first coupling. With a given degree of insertion the outer sleeve interacts with the inner sleeve 4 and entrains this. This entrainment occurs as a result of the interaction between the free end of the angled portion 5a and a shoulder4c, which is provided by means of a recess 4d on the inner sleeve.

The valve body is also provided with a shank portion 3b which extends coaxially in relation to the inner sleeve and up to or beyond the upper end surface 4b of the latter. The end of the shank which faces towards the valve head 3a is linked with a flow distribution housing 3a which is similarly part of the valve body and which is provided with an external thread, which can be screwed into a corresponding internal thread 1e in the coupling component 1.

In the flow distribution housing the flow which arrives from the incoming chamber If of the coupling component is distributed to a number of outlets 3c', 3c", which can for example be four in number and uniformly distributed around the central axis 10 of the coupling member. The exit holes are furthermore sloping and the shank is terminated in the housing by a tip 3b' which projects into the housing and by sloping surfaces 3b" and 3b"'. From the said outlets the flow is led down into chamber 1 b and into the sleeve 4. With the sleeve in its sealing position the pressure in the first coupling member is inter alia effective on the upper end surface 4b of the inner sleeve. The medium is sealed off as outlined above by means of the seals 7 and 9.

The first coupling member also incorporates outer locking sleeves 11 and 12, which as such are well known, and which with the aid of locking balls 13 and 14 and a further spring 15 are arranged to bring about in a known manner an automatic quick coupling function when coupling members 1 and 2 are joined together. The second coupling component is for this purpose provided with a radial outer groove 2b, via which interaction occurs with the locking balls 13 in the first coupling member.

The second coupling member 2 is entirely prior art and exhibits an axially displaceable valve body 16 which by means of a spring 17 is pressed against the front portions of the coupling member. The valve body 16 is coaxially mounted in a cross mounting 18 which rests against the inner wall 2c of coupling member 2. The valve body 16 is expanded at its free end and is sealed by means of a seal 19 of the "back-up" type.

Figure 2 shows inter alia how the flow path is formed through the connected members 1 and 2, whereby the flow medium is indicated by 20. Even if the flow as such can be imagined as being led in the opposite direction, the flow path 20 in the present case leads from chamber if, through the flow distribution housing 3c to the chamber between the inner sleeve 4 and the shank 3b, then on the outside of valve heads 3a and 16, and down and through the wings 18 of the cross mounting. With the position for the medium thus open, sealing of the flow takes place by means of the seal 9 and seal 19 which seal against the outside of the inner sleeve 4 at the recess 4d.

The diagram shows in greater detail, inter alia, a flap 21 arranged in the material of the valve head 3a, which adopts a rolled-down position over the sealing element 7 so that the sealing element is reliably fastened to the valve head. The valve head 3a also carries a supporting device 22 extending radially which supports a supporting flange, which is essentially radial, or supporting surface 22a, against which the sleeve end 4a is arranged to rest with its end edge surface 4a' which extends straight and parallel with the surface 22a. The outer tip of the rolled-down flat 21 and the outer tip of the supporting device 22 are denoted by 21' and 22' respectively.

If we again study diagram 2 the said outer tips 21' and 22' are also indicated here. This shows that an imaginary straight line drawn between the said tips extends right outside the sealing element, or essentially in connection with the tangents of the sealing element which are parallel with the straight line. This means that the sealing element is provided with an excellently protected position for the flow of the medium which is deflected towards the top surface 3a' of the valve head 3a. If for example the medium comprises hydraulic oil, then no extraneous particles present in the hydraulic oil can have a harmful effect on the sealing element.

Diagram 2 also shows that the lower portions 4a of the inner sleeve exhibit an internal chamfer for 4a" which facilitates the guidance of the sleeve to the sealing position via the tip of the flap 21' which thereby also functions as the guidance device for the inner sleeve.

The inner sleeve is simple in construction with a straight inner wall 4e and a straight outer wall which is reduced in section one step with the straight recess 4d (Figure 1).

The supporting device 22 shown in Figure 3 is relatively strong and is between 0.5 - 5 mm in thickness, which dependent on coupling type and/or coupling size. The straight radial upper surface 22a is height levelled at the location of the sealing ring 7, whereby a surface which is displaced in parallel in relation to the surface 22a is denoted by 22b. The latter partial surface is directly adjacent to the inner wall 4e of the inner sleeve, when the inner sleeve rests on the supporting device. The said surface 22b changes into a curved circular partial surface 22c which is terminated at the top by the said rolleddown flap 21. The supporting device is essentially the same thickness as, preferably somewhat thicker, than the free end 5a' of the angled portion 5a of the outer sleeve 5.

An essentially closed chamber 23 is thus formed for the sealing element 7 with the partial surfaces 22b and 22c, the rolled down flap 21 and the inner wall 4e. The said closed chamber communicates with the inner chamber of the sleeve 4 via a gap 24, facing away from the supporting device 22, which gap is between 0,1 and 0,2 mm. In the closed position of the sleeve, the inner wall 4e is guided by the axial surface which connects surfaces 22a and 22b, and the gap between the sleeve and last mentioned surfaces is right-angled, i.e. the gap between the axial surface and 22a forms a "L".

The volume of the chamber 23 exceeds the volume of the sealing element 7 and the sealing element projects beyond the flap 21 in a radial direction by 2/5 - 1/10 of its section which is circular in the present case. The degree of projection is preferably about 1/5.

As a result of the step-shaped radial sealing surface 22a and 22b, where the end surface 4a' on the sleeve rests against the surface 22a and surface 22b originates from the inner surface 4e of the sleeve, an effective sealing function is obtained even with high pressure of the medium which affects the sealing element in the axial direction via the gap 24.

The sealing element is pressed axially against the surface 22b by the pressure and the radial forces generated in the sealing element are effective against the inner surface 4e of the sleeve. This provides an effective sealing function and the sleeve 4 can be dimensioned so that its sleeve end is made of relatively thin material. At low medium pressures the spring 8 ensures that the sleeve is pressed against the supporting surface 22a so that a required seal is obtained via the inner wall 4e of the sleeve.

The pressure of the medium is effective on the end surface 4b of the sleeve and at high pressure this together with the spring ensures adequate contact on the part of the sleeve.

The said free end 5a of the angled portion 5c of the outer sleeve 5 is opposite to the free end surface 22d of the supporting device, the opposite surfaces having essentially the same height and being arranged with an intervening gap of O, 1 - 0,5 mm.

The essentially plane lower surface 5a" of the angled portion, the free end of which connects with the plane lower surface of the valve head 3a, is also sloping, in as much as it slopes from the outer edge inwards/upwards. An angle of slope a is thus equal to O - 15", preferably about 5" in the case illustrated.

The outer edge 5a"' of the radial portion of 5a connects with a chamfer 1 g' on the ball holder 1 b arranged on the first coupling member, which chamfer is about 45" in relation to the axis 10 and extends along ca half up to 2/3 of the material in the ball holder 1 g. The front surface of the first coupling component is formed in this way by straight and mutually interrupted partial surfaces 26 (on the valve head 3a), 5a" (on component 5a), and 1g' and 1 g" (on component 1g). The said chamfered surface 5a" with the coupling components connected together, gives rise to a ring-shaped and wedge-shaped chamber 27, into which small quantities of dirt, oil etc. which have not been wiped off can penetrate downwards so that they do not interfere with the engagement of the couplings.

Figure 4 illustrates the case where the lower surface 5a" is also straight. In this case the thickness of the supporting device is illustrated by 1 a and the step between the surfaces 2a and 22b is denoted by b. The latter-mentioned distance is 0,1 - 2,0 mm.

The function of the coupling is known from prior art. The male portion 2 is introduced into the female portion, whereby the outer sleeve 5 is pushed in and the seal 19 seals against the inner sleeve when the valve 16 in the male portion 2 is opened by the coupling force. When the outer sleeve 5 is inserted to a certain extend this interacts with the inner sleeve and entrains the latter, whereby the sealing arrangement together with the seal 7 is opened. When the components are locked to each other the flow path 20 is thus completely open.

When the members are disengaged the springs 6 and 8 retract the sleeves 5 and 4 respectively. The seal 19 no longer interacts with the sleeve 4 after this has sealed against the valve head 3a, whereupon f;:i#ai.!y the outer sleeve 5, also the valve 16 in coupling member 2, revert to their outer position as shown in Figure 1.

Figures 5 and 6 show further embodiments of the coupling member of the present invention. At large medium pressure it can be advantageous to discharge the fixed valve body from forces of the sleeve 4', 4" so the latter one does not rest only on the valve head 3a', 3a" in the closed or sealed position.

According to said embodiments the first coupling member is provided with a tube formed part fastened to the body of the first coupling member and separating the space of the spring for the outer sleeve 5', 5" from the space of the inner sleeve 4', 4".

Said tube formed part is attached to the coupling body via threads 29 and 32, respectively. The embodiment of Figure 5 having a seal 30 as well f6r preventing leakage.

Said tube formed part carries the flow distribution housing 28, which according to Figure 5 can be attached by means of press fit or, according to Figure 6, by means of threads 34. The valve body can in a corresponding way be attached to the flow distribution housing by press fit as in Figure 5 or by threads 33 as in Figure 6.

In the lower parts, the tube formed part is provided with an inwardly directed flange which serves as disharging device for the sleeve 4', 4", which having a corresponding flange or shoulder positioned below the sealing device of the sleeve, which sealing device is of "back-up" type. The end positions of the sleeve are shown by full and dotted lines, respectively. Furthermore, the sleeve having on its upper end a shoulder allotted to its belonging spring.

Said discharging devices are adapted so that the sealing function between the sleeve 4', 4" and the valve head 3a', 3a" always is carried through safely before discharging occurs. The outer sleeve 5', 5D is in these embodiments provided with not shown axial slots at its upper parts. Said slots make it possible to push in said outer sleeve via the front surface of the coupling member in the manufacturing procedure of the coupling. At the applying, the slotted parts of the sleeve can spring inwards and after that spring back again when the sleeve obtains its working position according to Figures 5 and 6.

The embodiments of Figures 5 and 6 allow also a comparatively simple and cheap production of the concerned coupling member. The assembling of a unit of concerned preassembled components can be carried out mainly from the rear of the coupling member. Material savings are attained as well, which contributes to a simple and cheap coupling member.

The invention is not restricted to the embodiments described above by way of example, but can also be subjected to modifications within the framework of the subsequent patent claims. Thus for example the whole or parts of valves 3a, 3b, 3c can be arranged so as to be capable of some movement in the axial direction relative to the first coupling member.

Similarly the exits from the flow distribution housing 3c can be located further out in relation to the orifice on the first coupling member i.e. the outer wall 3c"' can be lengthened and the shank 3b can be shortened to the desired extent.

The object of the present invention facilitates couplings which are suitable for rational production methods in large and small workshops. The rightangled gap between the inner sleeve 4 and the supporting member 22 of the valve head is easy to manufacture with great accuracy which guarantees a good sealing function as described above. The axial surface which connects surfaces 22a and 22b guarantees that the inner sleeve always gets coaxially the right position in relation to the sealing surfaces on member 22 and seal 7.

Claims

1. A coupling member including a valve body which is arranged to be fixed or movable and a sleeve capable of longitudinal displacement which in a sealing position is designed to seal against a valve body via a sealing element arranged on the latter, characterised in that the valve body is designed with a supporting device provided with an essentially radial surface for the sleeve, and that the latter is arranged so that in the said sealing position it rests against the said surface, that the valve body accommodates the sealing element so that the sleeve in the said sealing position extends past the sealing element and together with the valve body and its supporting device forms an essentially closed cham berforthe sealing element, and that the chamber is connected via a gap which faces away from the supporting device with a medium pressure which is effective on the sealing element and by this means contributes towards effective mutual sealing of the valve body and sleeve by means of the sealing element.

2. A coupling member according to Claim 1, wherein the sealing element is attached to the valve body by means of a flap capable of being rolled down which is arranged in the said valve body, characterised in that the roll-down flap is located on the opposite side of the sealing element in relation to the supporting device.

3. A coupling member according to Claim 2, characterised in that the rolled-down flap is arranged to control the said gap and that in the rolled-down state it extends over the sealing element, which thereby has O-ring shape so that in the radial direction this projects beyond the flap by 2/5 - 1/10, preferably by about 1/5 of its cross sectional area.

4. A coupling member in accordance with any one of the preceding Claims, characterised in that the sleeve is provided with a straight inner wall, the first end portions of which interact with the said supporting device and sealing element, and that the sleeve is subject to spring action at its other end portion by a compression spring which is effective against the sleeve end concerned.

5. A coupling member in accordance with any one of the preceding Claims, wherein the valve body consists of a valve head supporting a sealing element and a shank which is attached by its first end to this valve head and which extends coaxially inside the sleeve, characterised in that the sleeve extends upwards in connection with the other end of the shank which is fastened to a flow distribution housing which forms part of the valve body, the housing in turn being incorporated in the coupling component so that its orifices which lead out into the recess in the first coupling member where the sleeve is mounted are located at the second end portion of the sleeve.

6. A coupling member in accordance with any one of the preceding Claims, wherein a further sleeve, here designated as the second sleeve, is arranged radially outside the first-mentioned sleeve, in the following designated as the first sleeve, and which is displaceable relative to the coupling member and the first sleeve, characterised in that the supporting device has an axial straight end edge which is opposite a corresponding straight end edge on the second sleeve with an intervening gap of 0.1 0.5 mm in width, and that the supporting device has a thickness, e.g. 0.5 - 5 mm, which essentially corresponds to the thickness of that portion of the second sleeve which carries the said corresponding straight end edge, so that the lower end surface of the sleeve is located essentially at the same level as an inner surface present on the said portion of the second sleeve.

7. A coupling member in accordance with any one of the preceding Claims, characteristed in that the first sleeve has a straight outer wall which is reduced at its first end portion, that the axial end edge of the supporting device has roughly the same diameter as the reduction in the first sleeve, and that the latter reduction controls the maximum displacement of the second sleeve relative to the first sleeve.

8. A coupling member in accordance with Claim 6 or 7, characterised in that the outer surface of the valve body, also the outer surface of the supporting device, are straight in the radial direction and connect with a straight or somewhat sloping outer surface on the second sleeve.

9. A coupling member in accordance with Claim 8, wherein the said coupling member, in the following designated as the first coupling member, is capable of interaction in a quick coupling with a second coupling member, characterised in that in the case involving sloping outer surface on the second sleeve a ring-shaped and wedge-shaped chamber is formed between the first and second coupling members when these are engaged.

10. A coupling member in accordance with any one of the preceding Claims, characterised in that the end surface of the first sleeve, which rests against the radial surface in the sealing position, is essentially arranged at right angles in relation to the inner wall of the sleeve, and rests against the radial surface of the supporting device along its entire length, that the inner edge of the end surface is given a chamfer, and that the said chamber for sealing exceeds the volume of the sealing element.

11. A coupling member in accordance with any one of the preceding Claims, characterised in that the inner sleeve is provided with a discharging device which interacts with a corresponding discharging device in the first coupling member after that said sealing is carried out between the inner sleeve and the valve body.

12. A coupling member constructed, arranged and adapted for use substantially as hereinbefore described with reference to and as shown in the accompanying drawings.