Patent Description:
The present invention also relates to a hydraulic assembly, in particular for vehicular tubes.

Solutions for fitting tube elements for vehicular purposes are known. These solutions provide for mechanically connecting tube elements together in order to achieve, at the same time, the fluid-dynamic connection thereof.

The known solutions generally provide for the use of a fitting element equipped with two or more openings, which are engaged with respective tube elements, for example, by means of a threaded connection.

However, in cases where the fluid travelling in the tubes reaches high pressures (e.g., higher than <NUM> bar), the known solutions were not found to allow the leakage of the fluid between the gaps occurring between the joined parts to be prevented effectively.

This problem is particularly felt in applications involving the transfer of pressurized fluids, for example, in the field of hydrogen supply for vehicles.

Examples of known fitting assemblies are disclosed in <CIT>, <CIT>, <CIT>, <CIT>, <CIT> or <CIT>.

Therefore, there is a need to provide a fitting assembly for tube elements, which guarantees the transfer of pressurized fluids in a simple and fast way, while minimizing leaks thereof.

The object of the present invention is to meet the above requirements in a cost-effective and optimized manner.

Said object is achieved by means of a fitting assembly and a hydraulic assembly as claimed in the appended claims.

For a better understanding of the present invention, a preferred embodiment is described below by way of non-limiting example and with reference to the accompanying drawings, wherein:.

<FIG> shows a fitting assembly <NUM> for fitting a
first tube element <NUM> to a second tube element <NUM> for vehicular purposes. At the same time, this fitting assembly <NUM> provides the mechanical and fluid-dynamic connection of the first and second tube elements <NUM>, <NUM> and therefore allows the transfer of a pressurized fluid between said first and second tube elements <NUM>, <NUM>.

The pressurized fluid may be, by way of example, hydrogen flowing in a vehicular tube. Moreover, the transfer of said fluid can occur in the direction that goes from the first tube element <NUM> to the second tube element <NUM>, or vice versa.

In the non-limiting embodiment shown, the fluid is at a pressure of at least <NUM> bar.

The first and second tube elements <NUM>, <NUM> can be made of metallic, polymeric, or composite material. In particular, they can be made of the same material, or of different materials.

In the embodiment shown, the first tube element <NUM> is a flexible tube made of polymeric or composite (non-metallic) material and the second tube element <NUM> is made of metallic, polymeric, or composite material. As shown in <FIG>, the fitting assembly <NUM> comprises a fitting element <NUM>, which defines a longitudinal axis A and comprises a male portion <NUM> and a female portion <NUM> opposite each other along said longitudinal axis A. The male portion <NUM> is adapted to engage the first tube element <NUM>, whereas the female portion <NUM> is adapted to be engaged by the second tube element <NUM>. The female portion <NUM> also defines a seat <NUM>.

The fitting assembly <NUM> further comprises a bushing element <NUM>, which is fitted around the first tube element <NUM> in a radially external position with respect to the male portion <NUM>. This bushing element <NUM> exerts a radial compression on the first tube element <NUM> with respect to the longitudinal axis A.

The fitting assembly <NUM> also comprises a locking element <NUM>, which is shaped to engage the seat <NUM> so as to prevent and/or limit the relative movements between the second tube element <NUM> and the fitting element <NUM>.

In particular, the assembly of the first tube element <NUM>, the second tube element <NUM> and the fitting assembly <NUM> for fitting the first tube element <NUM> to the second tube element <NUM> defines a hydraulic assembly.

As shown in <FIG>, <FIG>, the first and second tube elements <NUM>, <NUM> are arranged coaxially with each other and with the longitudinal axis A of the fitting element <NUM>.

Alternatively, the second tube element <NUM> could be not arranged coaxially with the longitudinal axis A. In particular, the second tube element <NUM> could be arranged at a certain angle.

By way of example, the second tube element <NUM> could form an angle of <NUM>° or <NUM>° with respect to the longitudinal axis A.

The bushing element <NUM> is a crimp bushing having a radially external surface 7a and a radially inner surface 7b.

In the illustrated embodiment, the radially external surface 7a and the radially inner surface 7b are both cylindrical and are arranged coaxially with the longitudinal axis A. In detail, the radially external surface 7a is adapted to be engaged by a crimp tool during a crimping operation, whereas the radially inner surface 7b is adapted to face the first tube element <NUM>.

"Crimping operation" is to be understood as a mechanical compression operation of the bushing element <NUM>, which fastens the first tube element <NUM> to the male portion <NUM>. In particular, the radially external surface 7a could be no longer cylindrical as a result of the crimping operation.

At the radially inner surface 7b, the bushing element <NUM> comprises one or more tooth elements <NUM>.

Each tooth element <NUM> extends throughout the circumferential length of the bushing element <NUM> and protrudes towards the inside of the bushing element <NUM> with respect to the radially inner surface 7b. Alternatively, each tooth element <NUM> extends along part of the circumferential length of the bushing element <NUM>.

Each tooth element <NUM> also has a length parallel to the axis A. The tooth elements <NUM> can have the same length, or different lengths parallel to the axis A.

In the embodiment shown, the bushing element <NUM> comprises two tooth elements <NUM> spaced apart along the axis A.

The tooth elements <NUM> are placed in radial contact with the first tube element <NUM> and exert a radial compression thereon following the crimping operation.

In particular, each tooth element <NUM> comprises a radially innermost surface <NUM> on the side opposite the radially inner surface 7b. In the embodiment shown, each tooth element <NUM> is placed in radial contact with the first tube element <NUM> at the respective surface <NUM>. Preferably, each surface <NUM> is cylindrical and has a diameter corresponding to the outer surface of the first tube element <NUM>.

The fitting assembly <NUM> further comprises a plurality of sealing elements <NUM> fitted around the male portion <NUM>. These sealing elements <NUM> help to prevent the fluid from leaking through any gaps existing between the male portion <NUM> and the first tube element <NUM>.

Advantageously, the sealing elements <NUM> undergo a radial compression, which is exerted by the tooth elements <NUM> through the first tube element <NUM>.

In the embodiment shown, the fitting assembly <NUM> comprises two sealing elements <NUM>, arranged at a distance from each other along the axis A. Moreover, the bushing element <NUM> is arranged around the first tube element <NUM> so that each tooth element <NUM> is positioned at a respective sealing element <NUM> along the axis A.

The male portion <NUM> comprises a tubular element with axis A and having a radially external surface 4a and a radially inner surface 4b.

In the embodiment shown, the radially external surface 4a has a variable diameter. In particular, proceeding along the axis A from the point where the male portion <NUM> is closest to the female portion <NUM>, it is possible to identify:.

In particular, the first tube element <NUM> is fitted around the male portion <NUM>, so that it abuts against the shoulder <NUM> parallel to the axis A (<FIG>, <FIG>).

Furthermore, one of the two sealing elements <NUM> is housed in the groove <NUM>, and the other is housed in the groove <NUM>. However, the fitting assembly <NUM> could comprise more than two sealing elements <NUM> housed in as many grooves <NUM>, <NUM> of the radially external surface 4a.

In particular, as shown in <FIG>, <FIG>, the sealing elements <NUM> housed inside the respective grooves <NUM>, <NUM> protrude radially with respect to the radially external surface 4a. In this way, the sealing elements <NUM> housed inside the respective grooves <NUM>, <NUM> are in contact with the radially inner surface of the first tube element <NUM>.

Preferably, the radially inner surface 4b has a constant diameter substantially equal to the inner diameter of the second tube element <NUM> (<FIG>).

The fitting assembly <NUM> further comprises a reinforcing bushing <NUM> arranged radially inside the male portion <NUM>. The reinforcing bushing <NUM> can be made, for example, of metallic material and has the purpose of stiffening the male portion <NUM>.

In the illustrated embodiment, the reinforcing bushing <NUM> extends along the male portion <NUM> in the axial section comprised between its free axial end and the intermediate section <NUM>.

As shown in <FIG>, <FIG>, the female portion <NUM> comprises a radially external surface 5a and a radially inner surface 5b. In particular, the radially inner surface 5b defines a cavity <NUM> inside which the second tube element <NUM> is inserted.

A first opening <NUM> is formed in the radially external surface 5a for inserting and removing the locking element <NUM>. The first opening <NUM> extends along part of the circumferential length of the female portion <NUM> and throughout the thickness of the female portion <NUM> in the radial direction with respect to the axis A.

A second opening <NUM> and a third opening <NUM> are also formed in the radially external surface 5a. These second and third openings <NUM>, <NUM> extend radially throughout the thickness of the female portion <NUM> and have a shorter circumferential length than the circumferential length of the first opening <NUM>. The second and third openings <NUM>, <NUM> also extend along the same axial section of the female portion <NUM> (<FIG>).

The second and third openings <NUM>, <NUM> are formed on opposite sides of the first opening <NUM> in the circumferential direction. Furthermore, the second and third openings <NUM>, <NUM> are preferably formed in the female portion <NUM> so that they are equidistant from the first opening <NUM> in the circumferential direction and identical to each other.

The first opening <NUM>, the second opening <NUM>, the third opening <NUM>, and part of the cavity <NUM> define the seat <NUM> for inserting the locking element <NUM>.

As shown in <FIG>, the female portion <NUM> comprises two protrusions <NUM> at the first opening <NUM>. These protrusions <NUM> face each other and protrude from the radially external surface 5a radially outwards and axially towards the first opening <NUM>.

The protrusions <NUM> act as reference elements for the insertion of the locking element <NUM> in the seat <NUM>. The protrusions <NUM> extend radially as far as the radially inner surface 5b. Therefore, at the same time, the protrusions <NUM> act as guides for the insertion of the locking element <NUM>.

Preferably, a fourth opening 16a and a fifth opening 17a are also formed in the radially external surface 5a (<FIG> and <FIG>).

Similar to the second and third openings <NUM>, <NUM>, the fourth and fifth openings 16a, 17a extend radially throughout the thickness of the female portion <NUM> and have a shorter circumferential length than the circumferential length of the first opening <NUM>. The fourth and fifth openings 16a, 17a also extend along the same axial section of the female portion <NUM> as the second and third openings <NUM>, <NUM>.

The fourth and fifth openings 16a, 17a are formed on opposite sides of the first opening <NUM> in the circumferential direction. Furthermore, the fourth and fifth openings 16a, 17a are preferably formed in the female portion <NUM> so that they are equidistant from the first opening <NUM> and from the second and third openings <NUM>, <NUM>, respectively, in the circumferential direction and identical to each other.

As shown in <FIG>, the fourth opening 16a is interposed circumferentially between the first opening <NUM> and the second opening <NUM>; the fifth opening 17a is interposed circumferentially between the first opening <NUM> and the third opening <NUM>.

The fitting assembly <NUM> comprises a further sealing element <NUM> housed inside the cavity <NUM>, to prevent the leakage of the pressurized fluid flowing from the male portion <NUM> towards the second tube element <NUM>.

As shown in <FIG>, the locking element <NUM> can be engaged inside the seat <NUM> along a radial direction R1 with respect to the longitudinal axis A. In particular, this direction R1 is vertical according to the orientation of the fitting assembly <NUM> shown in <FIG>.

As described in greater detail below, when the locking element <NUM> is engaged inside the seat <NUM> it is in radial contact with the second tube element <NUM> (<FIG>). Moreover, in this condition, a flange element 2a of the second tube element <NUM> is engaged by the locking element <NUM> (<FIG>).

The locking element <NUM> can also be disengaged from the seat <NUM> by a force F having a non-zero component along a direction R2, which is radial with respect to the longitudinal axis A and orthogonal to the radial direction R1. In other words, as can be seen in <FIG>, the force F necessary to remove the locking element <NUM> from the seat <NUM> has a non-zero horizontal component.

Preferably, the locking element <NUM> can be at least partially disengaged from the seat <NUM> without being completely removed from the female portion <NUM>. In this case, the locking element <NUM> can be used in the same way as a key which can be moved between two operating positions while remaining engaged in the female portion <NUM>.

As shown in <FIG>, the locking element <NUM> comprises a main portion 8a and two lateral portions 8b.

In detail, the main portion 8a comprises a cylindrical surface <NUM>, which defines a circumferential direction B.

The lateral portions 8b extend from the main portion 8a at the respective ends of the main portion 8a along the circumferential direction B. In other words, the main portion 8a and the two lateral portions 8b define a U-shape.

The two lateral portions 8b each comprise a flat surface <NUM>. Said flat surfaces <NUM> are parallel to each other and perpendicular to a plane tangent to the cylindrical surface <NUM> at its midpoint.

The flat surfaces <NUM> define a longitudinal extension direction C. This direction C coincides with the radial direction R1 when the locking element <NUM> is engaged in the seat <NUM> (<FIG>).

Each lateral portion 8b also has a cylindrical surface <NUM> adapted to be placed in radial contact with the second tube element <NUM> when the locking element <NUM> is engaged in the seat <NUM> (<FIG>). Each cylindrical surface <NUM> is opposite to the respective flat surface <NUM> of the same lateral portion 8b.

The locking element <NUM> also comprises an engaging element 8c at each lateral portion 8b (<FIG>). Each of said engaging elements 8c protrudes outwards from the respective flat surface <NUM>.

As shown in <FIG>, each of the engaging elements 8c is shaped to engage one of the second and the third opening <NUM>, <NUM>, respectively, of the female portion <NUM>. Preferably, the engaging elements 8c snap-fit the respective second or third opening <NUM>, <NUM>. Furthermore, when the locking element <NUM> is engaged in the seat <NUM>, the engaging elements 8c protrude, with respect to the radially external surface 5a, from the second and the third opening <NUM>, <NUM>, thus preventing the locking element <NUM> to be radially removed from the seat <NUM>.

In order to disengage the locking element <NUM> from the seat <NUM>, it is necessary to apply the force F to the engaging elements 8c, so as to release them from the second and the third opening <NUM>, <NUM> (<FIG>).

As shown in <FIG>, each of the engaging elements 8c is also shaped to engage one of the fourth and the fifth opening 16a, 17a, respectively, of the female portion <NUM>. Preferably, the engaging elements 8c snap-fit the respective fourth or fifth opening 16a, 17a.

In detail, the engaging elements 8c engage the respective fourth or fifth opening 16a, 17a when the locking element <NUM> is disengaged from the seat <NUM> but remains partially engaged in the female portion <NUM>. In further detail, when the locking element <NUM> is disengaged from the seat <NUM>, the engaging elements 8c protrude, with respect to the radially external surface 5a, through the fourth and the fifth opening 16a, 17a, thus preventing the locking element <NUM> to be completely removed from the female portion <NUM>.

The locking element <NUM> also has two openings <NUM>, each in a respective lateral portion 8b. In detail, the openings <NUM> are each formed in a respective flat surface <NUM>, are through openings, and have a substantially rectangular shape.

The two openings <NUM> can be used, for example, to facilitate the removal of the locking element <NUM> from the seat <NUM>.

The locking element <NUM> also comprises a lug <NUM>, which extends from the main portion 8a along the direction C to the side opposite the circumferential surface <NUM>. Said lug <NUM>, in turn, comprises a portion <NUM>, which defines a cylindrical surface <NUM> on the side opposite the cylindrical surface <NUM>.

As shown in <FIG>, the cylindrical surface <NUM> is adapted to be placed in radial contact with the second tube element <NUM> when the locking element <NUM> is engaged in the seat <NUM>.

The locking element <NUM> also defines two seats <NUM> adapted to be engaged by the second tube element <NUM> when the locking element <NUM> is engaged in the seat <NUM>. As shown in <FIG>, the seats <NUM> are each formed in a respective lateral portion 8b on the side opposite the respective flat surfaces <NUM>. In particular, each of said seats <NUM> extends up to a respective radial opening <NUM> formed in the lateral portion 8b of the locking element <NUM>.

As shown in <FIG>, the seats <NUM> are engaged by the flange element 2a of the second tube element <NUM> and are adapted to limit the movements of the second tube element <NUM> in the direction parallel to the axis A.

In particular, the flange element 2a engages the seats <NUM> with a clearance parallel to the axis A.

The main portion 8a is also formed with two grooves <NUM> adapted to be engaged by the protrusions <NUM> of the female portion <NUM> (<FIG>). In particular, the grooves <NUM> are formed at the midpoint of the main portion 8a along the circumferential direction B. The grooves <NUM> also extend throughout the length of the lug <NUM> along the direction C and are formed at respective opposite ends of the cylindrical surface <NUM> along an axial direction D thereof.

The fitting assembly <NUM> is assembled according to the following.

In use, the sealing elements <NUM> are housed inside the respective grooves <NUM>, <NUM> of the male portion <NUM>. Subsequently, the male portion <NUM> is engaged inside the first tube element <NUM>, so that the first tube element <NUM> is placed in abutment against the shoulder <NUM> parallel to the axis A. In this condition, the sealing elements <NUM> are radially interposed between the radially external surface 4a and the first tube element <NUM>.

The bushing element <NUM> is then fitted around the first tube element <NUM>. In this way, the bushing element <NUM> is arranged radially external to the first tube element <NUM> and to at least part of the male portion <NUM>.

In this condition, the tooth elements <NUM> are placed in radial contact with the radially external surface of the first tube element <NUM>. In particular, the surface <NUM> of each tooth element <NUM> is placed in radial contact with the first tube element <NUM>.

Preferably, the bushing element <NUM> is mounted around the first tube element <NUM> so that each tooth element <NUM> is axially arranged at a respective sealing element <NUM>.

The bushing element <NUM> is then subjected to a crimping operation by means of a crimp tool acting on the radially external surface 7a. At the end of this crimping operation, the tooth elements <NUM> exert a radial compression action on the first tube element <NUM> and on the sealing elements <NUM>.

In particular, the tooth elements <NUM> could exert a radial compression action even before the crimping operation, but to a lesser extent than the radial compression action they exert after the crimping operation.

At this point, the second tube element <NUM> is inserted inside the cavity <NUM> from the axial end of the female portion <NUM> opposite the male portion <NUM>.

If the locking element <NUM> is completely disengaged from the female portion <NUM>, the locking element <NUM> is then inserted through the first opening <NUM> along the radial direction R1 starting from the lateral portions 8b (<FIG>). The lowering of the locking element <NUM> inside the seat <NUM> can take place, for example, by pressing on the cylindrical surface <NUM>.

During the operations by which the locking element <NUM> is engaged into the seat <NUM>, the grooves <NUM> cooperate with the protrusions <NUM>.

The locking element <NUM> is pressed along the radial direction R1 until the engaging elements 8c snap-fit the second and the third opening <NUM>, <NUM>, respectively. In this condition, the cylindrical surfaces <NUM> and <NUM> are in radial contact with the external cylindrical surface of the second tube element <NUM> and the flange element 2a engages the seats <NUM> of the locking element <NUM>.

In this way, all relative movements between the second tube element <NUM> and the female portion <NUM> are blocked or in any case limited.

If the locking element <NUM> is already partially engaged in the female portion <NUM>, it is sufficient to move the locking element <NUM> from its position along the radial direction R1 until the engaging elements 8c engage the second and the third opening <NUM>, <NUM>, respectively. In detail, the locking element <NUM> partially engaged in the female portion <NUM> has the engaging elements 8c engaged in the fourth and the fifth opening 16a, 17a, respectively. Therefore, in order to move the locking element <NUM> from this position it is necessary to push the locking element <NUM> along the radial direction R1, so that the engaging elements 8c disengage from the respective fourth and fifth openings 16a, 17a.

If it should be necessary to remove the second tube element <NUM> from the female portion <NUM>, it is necessary to disengage the locking element <NUM>, at least partially, from the seat <NUM>. To this end, it is necessary to apply the force F to the engaging elements 8c, so as to disengage them from the second and the third opening <NUM> and <NUM>. This force F must have a non-zero component along the radial direction R2.

Once the engaging elements 8c are disengaged, the locking element <NUM> can be moved along the direction R1, so as to eliminate the radial contact between the cylindrical surfaces <NUM> and <NUM> and the external cylindrical surface of the second tube element <NUM>, so as to disengage the flange element 2a from the seats <NUM>.

The locking element <NUM> can therefore be completely removed from the female portion <NUM>. Alternatively, if the locking element <NUM> is disengaged from the seat <NUM> without being completely removed from the female portion <NUM>, the locking element <NUM> must be moved along the direction R1 until the locking elements 8c engage the fourth and the fifth opening 16a, 17a, respectively (<FIG> and <FIG>). It is noted that the insertion of the second tube element <NUM> and its locking by means of the locking element <NUM> can also occur simultaneously or before the insertion of the male portion <NUM> in the first tube element <NUM> and the crimping operation.

The advantages of the fitting assembly <NUM> and of the hydraulic assembly according to the invention are clear from the foregoing.

In particular, since the fitting assembly <NUM> at the same time comprises the locking element <NUM>, which makes it possible to limit the relative movements between the second tube element <NUM> and the fitting element <NUM> and the bushing element <NUM>, which exerts a radial compression on the first tube element <NUM>, the transfer of pressurized fluids can be guaranteed in a simple and fast way, while minimizing the risk of fluid leaks.

Moreover, since the tooth elements <NUM> exert a radial compression action on the sealing elements <NUM>, the efficiency of these sealing elements <NUM> in preventing fluid leakage is considerably increased. In fact, this radial compression action minimizes the risk that the fluid will leak through any gaps present between the male portion <NUM> and the first tube element <NUM>.

In detail, the particular shape of the locking element allows cooperation in close contact with the second tube element <NUM>.

The presence of through openings <NUM> communicating with the seats <NUM> also makes it easier to remove the locking element <NUM> when replacing it.

Claim 1:
A fitting assembly (<NUM>) for fitting a first tube element (<NUM>) to a second tube element (<NUM>) comprising:
- a fitting element (<NUM>) defining a longitudinal axis (A) and comprising a male portion (<NUM>) adapted to engage said first tube element (<NUM>) and a female portion (<NUM>) adapted to be engaged by said second tube element (<NUM>); said female portion (<NUM>) being opposite to said male portion (<NUM>) along said longitudinal axis (A) and further defining a seat (<NUM>);
- a bushing element (<NUM>) adapted to be arranged radially external with respect to said male portion (<NUM>) and said first tube element (<NUM>) and to exert, in use, a radial compression on said first tube element (<NUM>); and
- a locking element (<NUM>) adapted to limit the relative movements of said second tube element (<NUM>) with respect to said fitting element (<NUM>) when, in use, it engages said seat (<NUM>),
wherein said bushing element (<NUM>) is a crimp bushing comprising a radially external surface (7a) adapted to be engaged by a crimp tool and a radially inner surface (7b) adapted to face said first tube element (<NUM>),
characterized in that said locking element (<NUM>) defines a pair of seats (<NUM>) adapted to house a flange element (2a) of said second tube element (<NUM>), the locking element (<NUM>) comprising a main portion (8a) and a pair of lateral portions (8b),
wherein said main portion (8a) comprising a lug (<NUM>) defining a surface (<NUM>) adapted to cooperate in contact with an outer surface of said second tube element (<NUM>) when the locking element (<NUM>) is engaged in the seat (<NUM>), and
wherein said pair of lateral portions (8b) each defines at least one seat (<NUM>), each lateral portion (8b) defining an opening (<NUM>) communicating with said seat (<NUM>).