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The present invention relates to a quick coupling assembly with antirelease elastic ring.

The use of quick coupling assemblies adapted to connect hydraulic lines under pressure is widespread in the operating machinery sector, e.g. of agricultural operating machinery.

The quick coupling assembly comprises a female coupling and a male coupling, wherein the male coupling is adapted to fit into the female coupling which is associated with a machine, e.g., a tractor, while the male coupling is associated with a piece of equipment, e.g., a weeder, to be coupled to the machine side or vice versa.

The need to prevent accidental release arises once the male coupling is fully inserted into the female coupling, i.e., when the hydraulic line between the male and female couplings is open ensuring a defined hydraulic operating pressure.

More in general, the male coupling and the female coupling must be uncoupled by a skilled operator using appropriate tools.

EP -2320118 shows a release tool for an assembly adapted to make a fluid connection under pressure. The tool has a curved thickness adapted to press a sleeve in an axial direction, which interacts with a toothed ring, which releases the wall of a tube. The teeth of the toothed ring open outwards in a radial direction.

US-20200208594 describes a disconnection tool adapted to allow the release of a safety ring in a fluid connection, wherein the disconnection tool displaces coupling means outwards in a radial direction.

US-5909901 shows a two-piece release tool which is adapted to force the expansion of a clip.

Disadvantageously, the tools described in the mentioned prior arts are complicated to make and use because they force the operator to be precise in use, which is sometimes beyond the operator's abilities.

Furthermore, the making of said tools is very much related to the type of connection on which it needs to work.

It is the object of the present invention to make a quick coupling assembly adapted to connect hydraulic lines under pressure, comprising a female coupling and a male coupling adapted to be inserted into the female coupling, wherein anti-release means are provided, which can be deactivated only by means of a specially designed external tool.

It is a further object of the present invention that the anti -release means be simple to make and easily deactivated only by means of said external tool.

It is a yet further purpose of the present invention that said external tool be space-saving, simple to make and easy to use only by a skilled operator.

According to the invention, said and further objects are achieved by a quick coupling assembly suitable for connecting hydraulic lines under pressure, comprising a female coupling and a male coupling, which can be coupled with the female coupling, wherein the female coupling is associated with a machine, while the male coupling is associated with a piece of work equipment, or vice versa, wherein the assembly further comprises a ring nut axially sliding and adapted to couple the male coupling with the female coupling, characterized in that it further comprises an elastic ring adapted to assume an unlocked position suitable for uncoupling the male coupling from the female coupling, wherein the elastic ring is completely housed in a seat of a female body of the female coupling, and a locked position of the coupling between male coupling and female coupling, wherein the elastic ring is partially housed in the seat of the female body and partially in a seat of the ring nut so that the ring nut cannot slide on the female body, wherein the elastic ring is adapted to pass from the unlocked position to the locked position by expanding radially, while it is adapted to move from the locked position to the unlocked position in which it is compressed exclusively by means of a tool external to the quick coupling assembly.

Only by means of the tool it is possible to move the elastic ring to the unlocked position and to guide the ring nut to uncouple the male coupling from the female coupling.

The presence of a plurality of openings allows avoiding not only accidental opening, but also an attempt to open without the tool.

If the thicknesses have a linear profile, the contact zones change from point-like (first contact) to linear (closed tool), thus gradually forcing the overall compression of the elastic ring, which reduces its diameter as it enters the seat completely.

These and other features of the present invention will become further apparent from the following detailed description of practical embodiments thereof illustrated by way of non-limiting example in the accompanying drawings, in which: figure 1 shows a side view of a quick coupling assembly according to a first embodiment of the present invention, wherein a male coupling and a female coupling are uncoupled; figure 2 shows a side view of the quick coupling assembly, wherein the female coupling and male coupling are coupled, figure 3 shows a front view of the female coupling; figure 4 shows a front view of the quick coupling assembly of figure 2; figure 5 shows a section view taken along the line V-V of figure 3; figure 6 shows a section view taken along the line VI- VI of figure 4; figure 7 shows a perspective view of a tool adapted to uncouple the male coupling from the female coupling, in a closed position; figure 8 shows a front view of the tool, in the closed position; figure 9 shows a perspective view of the tool, in an open position; figure 10 shows the front view of the tool, in the open position; figure 11 shows a perspective view of the quick coupling assembly, wherein the female coupling and male coupling are coupled, and wherein the tool is open and uncoupled from the quick coupling assembly; figure 12 shows a perspective view of the quick coupling assembly, wherein the female coupling and male coupling are coupled, and wherein the tool is open and partially uncoupled from the quick coupling assembly; figure 13 shows a perspective view of the quick coupling assembly, wherein the female coupling and male coupling are coupled, and wherein the tool is closed and coupled to the quick coupling assembly; figure 14 shows a partial cross-section view similar to the one of figure 6, wherein the assembly is in the position of figure 13; figure 15 is a section view similar to the one of figure 14, wherein the male coupling is in a step of uncoupling from the female coupling; figure 16 is a section view similar to the one of figure 14, wherein the male coupling is uncoupled from the female coupling; figure 17 shows a cross-section view, similar to the one of figure 6, of a quick coupling assembly according to a second embodiment of the present invention, wherein a female coupling and a male coupling are uncoupled; figure 18 shows a cross-section view similar to that of figure 17, of the quick coupling assembly of figure 17, wherein the female coupling and male coupling are coupled; figure 19 shows a perspective view of a half-bushing of a tool adapted to uncouple the male coupling from the female coupling, the tool being according to a second embodiment; figure 20 shows a side view of the half-bushing; figure 21 shows a front view of the half-bushing; figure 22 shows a perspective view of the quick coupling assembly, wherein the female coupling and male coupling are coupled, and wherein the tool according to the second embodiment is uncoupled from the quick coupling assembly; figure 23 shows a perspective view of the quick coupling assembly, wherein the female coupling and male coupling are coupled, and wherein the tool of figure 22 is partially coupled to the quick coupling assembly; figure 24 shows a perspective view of the quick coupling assembly, wherein the female coupling and male coupling are coupled, and wherein the tool of figure 22 is coupled to the quick coupling assembly; figure 25 shows a front view of the quick coupling assembly in the configuration of figure 24, wherein the tool of figure 22 is coupled to the quick coupling assembly.

A quick coupling assembly 1 adapted to connect hydraulic lines under pressure comprises a female coupling 2 and a male coupling 3 which can be coupled to the female coupling 2 (figures 1 and 2).

The female coupling 2 is associated with a machine (not shown), e.g., a tractor, while male coupling 3 is associated with a piece of work equipment (not shown), e.g., a weeder side or vice versa.

The female coupling 2 comprises a junction 6 for coupling with the machine, a female body 7, and a ring nut 8, wherein the junction 6 is integral with female body 7, and ring nut 8 is adapted to slide axially on female body 7 at a portion of head 701 of female body 7.

The ring nut 8 is adapted to couple the male coupling 3 with the female coupling 2.

The head portion 701 of the female body 7 performs a nut ring holder function and is adapted to contain balls 12 in a locking seat 111.

The ring nut 8 internally comprises a discharge seat 81 of the balls 12.

The ring nut 8 further comprises a seat 82 adapted to partially house an elastic ring 100 comprised in the female coupling 2.

The elastic ring 100 is adapted to assume an unlocked position wherein it is fully housed in a seat 101 of the female body 7, and a locking position wherein it is partially housed in the seat 101 and said seat 82 of the ring nut 8.

With reference to an axis X, i.e., a coupling and uncoupling axis of the assembly 1, considering a radial direction which is orthogonal to said axis X, the seat 101 is internal relative to the seat 82.

Unlocked position means a position of the elastic ring 100, which allows the uncoupling of the male coupling 3 from the female coupling 2 (figures 14 and 15).

Locked position means a position of the elastic ring 100 wherein the uncoupling of the male coupling 3 from the female coupling 2 is not allowed (figures and 6).

The elastic ring 100 is adapted to remain in the unlocked position until the seats 82 and 101 are aligned; in such a configuration (figure 6), the elastic ring 100, firstly compressed into the seat 101 by the ring nut 8 (figure 5), radially expands going to partially occupy the seat 82 and partially occupy the seat 101. Advantageously, the ring nut 8 can no longer slide on the head portion 701 of the female body 7.

When the female coupling 2 is uncoupled from the male coupling 3 (figure 5), the ring nut 8 is held in a rest position, with the seats 82 and 101 not aligned, by means of a spring 85 and the balls 12 housed in the locking seat 111.

Once the coupling between female coupling 2 and male coupling 3 (figure 6) has taken place, a tool 200 adapted to uncouple the male coupling 3 from the female coupling 2 is required to return the elastic ring 100 to its unlocked position, i.e., housed in the seat 101 of the female body 7.

The tool 200 (figures 7-10), external to the assembly 1, consists of two portions 201 rotatably coupled at a pin 202.

The tool 200 is adapted to take at least one open configuration (figures 9 and 10) and one closed configuration (figures 7 and 8).

When the tool 200 is in a closed configuration, it makes four thicknesses 203 adapted to be inserted into four openings 83 of the ring nut 8.

Said four openings 83 are radially through and allow the thicknesses 203 to at the same time compress the elastic ring 100 into four different zones to return it to its seat 101. Advantageously, the uncoupling of the male coupling 3 from the female coupling 2 is allowed.

The tool 200, when in a closed configuration, is substantially ringshaped, i.e., it is suitable for embracing the ring nut 8.

The ability to assume an open configuration allows the tool 200 to be able to couple easily with the ring nut 8, accurately inserting the thicknesses 203 into the respective openings 83 of the ring nut 8.

The thicknesses 203 preferably have a linear profile suitable for being inserted into the openings 83 which have a suitable shape for the insertion of said thicknesses 203 to compress the elastic ring 100.

The female coupling 2 further comprises a coupling 10 integral with the junction 6 and which extends axially within the female body 7.

The shutter 10 has a head 301 and a stem 102, wherein the head 301 is in one piece with the stem 102. The head 301 comprises a flat end 103 facing the male coupling 3. The stem 102 has radial holes 105 and a cavity 104 which continues into junction 6 forming a single chamber 18 in fluid connection with the machine.

Inside the female body 7, a cup 15, which is held in position by a spring 16 is adapted to slide between the head portion 701 and the shutter 10. Seals 161 are interposed between the cup 15 and the shutter 10, one of said seals 161 being at the head of the cup 15, facing towards the male coupling 3.

There is a machine operating pressure, typically at least 10 bar, in the single chamber 18.

Said single chamber 18 extends axially from the machine connector to the head 301 of the shutter 10.

It is worth noting that radial means a direction orthogonal to the axial direction of the axis X.

The male coupling 3 (figure 6) comprises a male body 70, a shutter 71 sliding axially into the male body 70, and a junction 72 adapted to connect to a piece of equipment (not shown). A spring 73 holds the shutter 71 sealed onto the male body 70 when the male coupling 3 is uncoupled from the female coupling 2.

The male body 70 has a discharge seat 90 of the balls 12 on the outer surface.

The radial ends of the shutter 71 and the male body 70 of the male coupling 3 form a flat face of the male coupling 3.

The ends of the shutter 10 and the cup 15, with the seal 161 in the head of the cup 15, of the female coupling 2 form a flat face of the female coupling 2.

Operationally, once the coupling between the female coupling 2 and the male coupling 3 has taken place, i.e., when there is a fluid connection between the equipment and the machine through radial holes 105, the elastic ring 100 is in the locked position, i.e., it is housed partially in the seat 101 and partially in the seat 82 (figure 6).

The ring nut 8 cannot slide on the head portion 701 of the female body 7 because the elastic ring 100 protrudes from the seat 101 of the female body 7 into the seat 82 of the ring nut 8.

The tool 200 is needed to unlock the ring nut 8, i.e., to allow it to slide on the female body 7.

Figures 11-13 show the simple maneuver to be performed by the operator; the operator opens the tool 200, couples a first portion 201 to the ring nut 8 so that a first thickness 203 enters into the respective opening 83, closes tool 200 so that all thicknesses 203 enter their respective openings 83 by forcing the elastic ring 100 into the single seat 101 of the female body 7 (figure 14).

Advantageously, the ring nut 8, guided by the tool 200, can slide on the female body 7 uncoupling the male coupling 3 from the female coupling 2 (figures 15 and 16).

More in particular, the ring nut 8 is forced towards the junction 6 (on the left when looking at figure 14), so that the balls 12 can be inserted again into the discharge seat 81 exiting from the discharge seat 90 of the male coupling 3, which can then slip out of the female coupling 3 closing the single chamber 18 again. An elastic head ring 86 contrasts any movement of the ring nut 8 in the opposite direction, i.e., to the right observing figure 14.

Once uncoupled (figure 16), the ring nut 8 is stationary in a balance between the thrust of a spring 85 towards the head of the female coupling 2, and the contrast of the balls 12. The tool 200 can be removed from the configuration of figure 16.

Only by means of the tool 200 it is possible to move the elastic ring 100 to the unlocked position and to guide the ring nut 8 to uncouple the male coupling 3 from the female coupling 2. When the tool 200 is in the closed configuration, it is integral with ring nut 8.

The presence of a plurality of openings 83 allows avoiding not only accidental opening but also an attempt to open without the tool 200: it is at the same time impossible to compress the elastic ring 100 in several zones at once.

Preferably, the contact zones of the tool 200 must be equally distant from the elastic ring 100.

The preferred embodiment shown in the figures has four thicknesses 203 for four openings 83, for four contact zones of the elastic ring 200.

The unlocking can also occur, albeit with difficulty, with two or three thicknesses 203, and, respectively, two or three openings 83 and two or three contact zones.

The unlocking can also occur naturally with more than four thicknesses 203, four openings 83 and four contact zones; however, the construction of tool 200 becomes complicated.

The openings 83 are configured so that consecutive openings 83 are preferably angularly equidistant about the axis X of the assembly 1.

Advantageously, the linear profile of the thicknesses 203 progressively transforms the contact zones from point-like (first contact) to linear (tool 200 closed), thus gradually forcing the overall compression of the elastic ring 100, which reduces its diameter as it enters the seat 101 completely.

In the embodiment of figures 17, and 18, unlike the embodiment of figures 1-16, the assembly 1 is of the screw type.

More in particular, the ring nut 8 is comprised in the male coupling 3, contains the male body 70, and is adapted to be screwed onto the head portion 701 of the female body 7 of the female coupling 2. Thus, the coupling is not achieved by means of the balls 12 but by means of the screw-nut screw, wherein the nut screw is inside the ring nut 8 while the screw is on the head portion 701 of the female body 7.

When the male coupling 3 is uncoupled from female coupling 2 (figure 17), the elastic ring 100 protrudes from the seat 101 of the female body 2.

The ring nut 8 of the male coupling 3 has an invitation 87 at the head 88 of the ring nut 8 (figure 17).

Advantageously during the step of coupling, wherein the ring nut 8 slides axially (even rotating), when the head 88 meets the elastic ring 100 it gradually compresses it by means of the invitation 87 by inserting the elastic ring 100 firstly completely into the seat 101 of the female body 7 and then partially into the seat 82 of the ring nut 8 as well.

As shown in figure 18, when the male coupling 3 is coupled with female coupling 2, the elastic ring 100 is partially contained in both the seat 101 of the female body 7 and the seat 82 of the ring nut 8.

Consequently, the same situation arises again as in the embodiment in figures 1-16, wherein the tool 200 is needed to uncouple the male coupling 3 from the female coupling 2 with the thicknesses 203 which are inserted into the seat 82 of the ring nut 8 forcing the elastic ring 100 to be compressed into the seat 101, thus allowing the male coupling 3 to slip out of the female coupling 2 sliding axially again.

The use of the tool 200 is identical as is the function of the elastic ring 100, which only if compressed allows the uncoupling of the male coupling 3 from the female coupling 2.

In both embodiments, the ring nut 8 slides axially, i.e., along the axis X.

It is worth noting that the sliding of the ring nut 8 means a translation, possibly associated with a rotation, as in the embodiment shown in figures 17 and 18.

Figures 19-21 show a half-bushing 301 of a tool 300 adapted to uncouple the male coupling 3 from the female coupling 2, the tool 300 being according to a second embodiment.

The tool 300 preferably consists of two half-bushings 301.

Each half-bushing 301 has a substantially C-shaped section (figure 21) and comprises two thicknesses 302 facing each other, and which are adapted to fit into two openings 83 of the ring nut 8.

The thicknesses 302 preferably have mutually parallel linear profiles suitable for being inserted into the openings 83 which have a shape suited for insertion of said thicknesses 203 to compress the elastic ring 100.

The use of the tool 300 is very simple.

As seen in figures 22-24, in sequence, in the embodiment with two halfbushings 301, one couples the first half-bushing 301 (figure 23) to the ring nut 8 so that the respective thicknesses 302 are inserted into two openings 83 of the ring nut 8, and then couples the second half-bushing 301 (figure 24) to the ring nut 8, so that the respective thicknesses 302 are inserted into the remaining two free openings 83 of the ring nut 8.

As can be appreciably observed in figure 20, in particular, the thicknesses 302 are made in two protruding portions 303 of the half-bushing 301 to allow a substantial interference of the half-bushing 301 during the coupling with ring nut 8, as shown in figure 24. Once coupled, the protruding portions 303 are substantially arranged at the same annular band of the tool 300 adapted to cover the ring nut 8 where the openings 83 are present.

Compared with the first embodiment (tool 200), the tool 300 is in two separate parts, and thus it is easier to handle and to couple/uncouple to/from the ring nut 8.

The function of the two tools 200, 300 is exactly the same.

A single half-bushing 301 is sufficient in the case of ring nut 8 with only two openings 83, i.e., the tool 300 can consist of a single half-bushing 301.