The present invention relates to a connector for filling and/or extracting pressurized fluid, to a connector and tap assembly and to the use thereof.
The invention more particularly relates to a coupling or a connector for filling and/or extracting pressurized fluid, particularly pressurized gas, which is intended to be connected selectively to a fluid receiving device such as a tap of a pressurized tank, said connector comprising a fluid supply circuit, at least one male and/or female attachment element designed to engage selectively for the purposes of attachment with at least one mating female and/or male attachment port of the receiving device, the connector comprising a lock sensitive to the pressure in the fluid supply circuit, said lock being able to move automatically under the action of the pressure in the fluid supply circuit between a first position in which the attachment element is blocked when the pressure in the fluid supply circuit is above a set threshold pressure and a second position in which the attachment element is unblocked when the pressure in the fluid supply circuit is below the threshold pressure, in its blocked first position, the lock being configured to prevent the connector and the attachment port from being detached from one another when the connector is already connected to a fitting, in its unblocked second position, the lock being configured to allow the connector and the attachment fitting to be detached from or secured to one another.
In applications to gas cylinders fitted with standard taps, a manual isolation control is (hand wheel or lever) is normally provided on the tap, and a standardized gas inlet/outlet port is also provided, this being defined according to the legislation currently in force. This inlet/outlet port is provided with a male or female right-hand or left-hand thread so that it can be coupled to a filling fitting determined according to the nature of the gas (fuel or oxidant for example).
The filling fittings used for filling these cylinders are mostly couplings or connectors that have to be screwed manually onto the port of the tap. Coupling is therefore not a speedy process and there is no special-purpose means to prevent uncoupling under pressure (apart from the very high unscrewing torque required on account of the pressure of the gas). In addition, the resultant loadings from the pressure of the gas highly stress the connection between the fitting and the port.
Known filling fittings have jaws with toothed sectors that mimic the screw thread on the inlet/outlet ports to improve the speed of coupling. Certain fittings have mechanical means that prevent the fitting and the port from becoming uncoupled when the connection has not been secured (for example a band has to be fitted around the bonnet of the cylinder). However, there are still risks involved if unlocking should occur when the gas pressure is still present in the fitting.
Cylinders fitted with taps that have in-built regulating valves are generally equipped with an inlet port and with an outlet port which are separate. For legislatory reasons and also with a view to harmonization and standardization, the inlet ports are identical to the inlet/outlet ports of standard taps. For this reason, the filling fittings are therefore the same as in the preceding application.
One storage solution is to provide tanks or volumes that form an integral part of the application such as the tanks carried permanently on board vehicles in which filling is performed via a rapid connection, the profile of which is standardized. In these connections, the resultant loadings from the pressure directly stress the mechanical union between the connection and the filling fitting. One known solution provides a filling fitting fitted with a device that prevents uncoupling under pressure and which is embodied by a safety button that has to be pressed in order to be able to disconnect the fitting (double action).
Document DE 1 025 688 describes a hose for supplying pressurized air, the connection end of which comprises attachment half-cuffs intended to collaborate with a complementary receiving system. The connection end further comprises a moving piston subject to the pressure in the supply hose. When the hose is under pressure, the rod of the piston protrudes at the attachment half-cuffs to form an end stop that interferes with the cuffs to prevent the half-cuffs from being attached (or to prevent detachment when the half-cuffs are already connected).
The piston can be retracted when no longer subjected to sufficient gas pressure.
This solution improves the safety of the connection but, in certain situations, it is nevertheless possible for the user to make a dangerous and incorrect connection.
These solutions are not, however, satisfactory.
The invention relates in particular to how to make the method of filling a high pressure gas tank safer by implementing mechanical and/or pneumatic solutions that are incorporated particularly into the filling line (filling fitting) connection interface.
One object of the present invention is to remedy all or some of the abovementioned disadvantages of the prior art.
To this end, the connection according to the invention, in other respects in accordance with the generic definition thereof given in the above preamble, is essentially characterized in that in its first and second positions, the lock is configured to block or unblock the attachment element via at least one intermediate locking element distinct from the lock, the intermediate locking element being selectively removable between a position in which the at least one attachment element is locked and a position in which the latter is not locked, and in that the lock comprises at least one moving part such as a peg able to move with respect to the intermediate locking element, the moving part forming a retractable end stop for the locking element according to the pressure of the fluid in the supply circuit.
According to the invention, the connection has a first level of automatic locking via the intermediate locking element that acts selectively on the attachment element or elements and a second level of locking via the pressure-sensitive lock.
The pressure-sensitive lock acts selectively on the intermediate locking element.
The invention thus allows the user to be given an indication that he has made a correct connection via the intermediate locking element. The invention additionally then makes the connection safe and secure in a correct position, via the lock, only when the system is under pressure.
Thus, the locking element acts selectively only on the attachment elements while the pressure-sensitive lock acts selectively only on the locking element (and not on the attachment elements directly). This provides two levels of safety that the user can readily identify.
Moreover, some embodiments of the invention may include one or more of the following features:
The invention may also relate to an assembly comprising a tap for pressurized fluid, particularly for pressurized gas, and a system for filling/extracting fluid via the tap, the tap being provided with a filling fitting, the filling/extraction system comprising a connector intended to be connected selectively to a filling port of the tap, the connector being a connector in accordance with any one of the features below or hereafter.
According to other possible particular features:
The invention may also relate to any alternative device or method comprising any combination of the features hereinabove or hereinbelow.
The invention thus makes it possible to prevent the filling fitting from being connected or disconnected when the filling fitting is under pressure.
The invention may also provide (in addition or separately) a way of canceling the forces due to the pressure which have a tendency to stress the mechanical union between the connection interface of the filling fitting and the filling port of the tank that is to be filled.
The invention has the notable advantage of making the manual actions needed to perform an operation of filling high-pressure gas tanks intuitive and unambiguous in order to improve safety and productivity in filling centers.
Thus, the invention proposes a system for preventing the filling fitting from being connected and/or disconnected under pressure, in which the control of the prevention system is preferably separate from the pressure detecting element. The result of this is that the force needed to actuate the unlocking control is constant irrespective of the pressure, provided that this pressure meets the locking requirement.
Other specifics and advantages will become apparent from reading the following description which is given with reference to the figures in which:
The other end of the fitting 100 comprises a connection interface housing a fluid distribution spindle 13. The connection interface comprises a mechanical attachment system 4 allowing fluidtight coupling to the port of the tap 6 of the tank that is to be filled.
In the nonlimiting example described here, the attachment system 4 comprises cranked grooves 41 formed on the end of the fitting 100 and intended to collaborate with radial pins 61 formed on one end of the tap 6. The assembly forms a bayonet-type fixing system. For further details, reference may be made to document WO2007048955. However, this embodiment of the attachment system is neither exclusive nor limiting and can be replaced or supplemented by other equivalent connection systems such as screw-fastening, clipping, clamping, etc.
The bayonet connection 41-61 can be locked by a moving part 5. For example, the attachment of the pins in the grooves 41 can be locked/unlocked in particular by a ring 5 of tubular overall shape mounted with the facility for translational movement coaxially with respect to the body 1 of the fitting.
The locking/unlocking ring 5 is urged by an internal spring 52 into a forward position in which it closes the open ends (exits) of the grooves 41. This prevents the stubs 61 from leaving the corresponding grooves 41 (locking the fitting on the tap 6). The ring 5 can be pushed back manually and/or mechanically (against the action of the spring 52) to free the openings (exits) of the grooves 41 (unlocking the fitting from the tap 6).
The locked position can be blocked by a lock system 51, 83, 8 described in greater detail hereinafter.
With reference to
The body 1 of the filling fitting 100 comprises an external hand grip 11. The hand grip 11 is free to turn about the support spindle 12 in order to prevent a twisting torque from being transmitted to the hose 121 which is connected to the rear of the fitting. For example, the hand grip 11 rotates as one with a lock collar 51 described in greater detail hereinafter (the lock collar 51 may, however, slide with respect to the hand grip 11 when not blocked as described hereinafter). The support spindle 12 in its center houses a tubular distribution spindle 13 that has an internal duct able to carry the pressurized fluid.
A fluidtight shut-off member 3 is mounted on the end in the connector 42. More specifically, the shut-off member 3 is slidably mounted on the forward end of the distribution spindle 13.
When the fitting 100 is not connected (see
The moving locking/unlocking ring 5 slides around a connector 42 mounted on the support spindle 12. The return spring 52 tends always to return the moving spring 5 to the locked position (toward the forward end of the fitting 100, i.e. to the left in
The L-shaped attachment grooves 41 are situated, for example, on the forward end of the connector 42 that forms the mechanical union element 4.
When the filling fitting 100 is being connected to a tap 6 fitted with mating pins or bayonets 61 (cf.
During this operation, the end of the distribution spindle 13 enters the body of the tap 6 via an opening (cf.
The forward end of the distribution spindle 13 becomes lodged fluidtightly inside the tap 6, positioning itself between two sealing pairs 62 and 63 each comprising an O-ring seal and an anti-extrusion ring. The two sealing pairs 62 and 63 are arranged concentrically at the end of the spindle 13 and guide the fluid emerging radially from the spindle 13 through orifices 64 (cf.
The two sealing pairs 62 and 63 preferably have the same diameters so that the forces due to the pressure of the gas on the spindle are equalized. Thus, the mechanical stresses on the connection between the fitting 100 and the tap 6 are low.
The support spindle 12 also houses a tubular piston 8 which is urged forward by a spring 81. The piston 8 is, for example, of the differential type and has two ends of different cross sections S1 and S2 dimensioned to generate on the piston 8 a force that opposes the action of the spring 81 when the pressurized gas arrives via the rear connector 2 (cf.
In the configuration of
During the filling phase, as soon as the pressure in the fitting 100 rises above a threshold pressure Ps, disconnection is rendered impossible.
Specifically what happens is that beyond a set threshold pressure Ps, the force F of the spring is exceeded by the force of the pressurized gas (Ps=F/(S1−S2)).
Thus, if the pressure in the filling fitting 100 is above the threshold Ps, the piston 8 moves backward (cf.
The piston 8 has an inclined plane 82 or some other appropriate cam surface in contact with one or more peg(s) 83. The pegs 83 are mounted such that they can move in a slot formed in the support spindle 12. The slots housing the pegs 83 open into a keyway-type feature 59 facing a surface of a lock collar 51. The lock collar 51 is mounted around the support spindle 12 and moves as one with the locking ring 5 in translational movement.
When the piston 8 and its inclined plane 82 are moved to the right under the action of the pressure of the gas, the inclined plane 82, in contact with the pegs 83, pushes these pegs back into the keyway-type feature 59 of the lock collar 51. The pegs 83 have a length sized to allow them to protrude into the keyway-type feature 59 when the piston 8 has reached its extreme position (cf.
L<(L12=wall thickness of the support spindle 12+L51=space between the support spindle 12 and the lock collar 51),
L>L12=wall thickness of the support spindle 12, and
L<(L12=wall thickness of the support spindle 12+L8=height of inclined plane).
When the pegs 83 protrude into the keyway-type feature 59 of the lock collar 51 they form end stops preventing any translational movement of the lock collar 51 along the spindle 12. What happens is that the pegs 83 protruding into the keyway-type feature 59 form a mechanical connection of the key and keyway type between the fixed support spindle 12 and the moving lock collar 51. The lock collar 51 thus blocks the translational movement of the moving ring 5 (the lock collar 51 moves as one in translational movement with the locking ring 5).
In this way, the bayonets 61 of the tap 6 can no longer be freed from their housings 53. The uncoupling of the filling fitting 100 with respect to the tap 6 is rendered impossible. The uncoupling of the filling fitting 100 with respect to the tap 6 will not become possible again until the pressure in the filling fitting 100 drops below the threshold pressure Ps (the reverse process to the one described above) cf.
After unblocking (P<Ps), the unlocking of the fitting 100 can be obtained by pushing the ring 5 manually or mechanically backward to allow the bayonet attachment (or equivalent) to be undone.
In a filling center, a filling line may be fitted with several filling fittings 100. Thus, during a filling cycle, it is possible that some of these fittings 100 might not be connected to a tap 6. In such instances, the filling pressure arrives at the filling fitting 100 which is shut off and fluidtight (shut-off member 3).
According to the same principle as described previously, when the filling fitting 100 is not connected to a tap 6 but is subjected to a pressure above the threshold Ps, the locking system 5 is blocked in the locked position which prevents said filling fitting 100 from being coupled to a tap 6.
The invention also allows the resultant forces from the pressure of the gas to be equalized, and this has the effect of limiting the filling fitting repulsion forces and therefore the mechanical stresses on the union between the connector 6 and the filling fitting 100.
Number | Date | Country | Kind |
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0851930 | Mar 2008 | FR | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/FR2009/050477 | 3/20/2009 | WO | 00 | 9/24/2010 |