Non-refillable gas cylinder

Abstract

A non-refillable gas cylinder comprises: a hollow container body adapted to contain a pressurized gas and provided with an end on which at least one port for a gas outlet is provided; a one-way valve associated with the container body, the one-way valve adapted to allow gas to escape from the container body and provided with a threaded clamp threadably connectable to the port; a retaining device associated with the container body, the retaining device adapted to prevent removal of the valve from the container body, and comprising a retaining body arranged inside the container body where the port is located, and comprising a flexible portion defining a passage bore aligned with the port along an axis, the passage bore is adapted to receive a section of a valve therein, where the valve includes a retaining end and is movable along said axis between a pressurized position and a safety position.

Description

Technical Field

[0001] The present invention relates to a non-refillable cylinder. Background Art

[0002] As is known, a gas cylinder basically consists of a hollow container body suitable for containing pressurized gas and a valve mounted on the container body, the valve being configured to allow the gas contained in the container body to escape and to introduce gas into the container body itself.

[0003] In this regard, it must be explained that the gas cylinder industry actually consists of two main different types of products, namely refillable gas cylinders and non-refillable gas cylinders.

[0004] It can be easily deduced that the latter differ from the former in their inability to be refilled and in some peculiar structural aspects which result from this property.

[0005] In particular, since such gas cylinders have to undergo one and only one pressurization, they can be provided with a container body having thinner walls compared to refillable gas cylinders, thereby increasing the gas capacity for the same volume and reducing the overall production costs.

[0006] A critical aspect of the design of non-refillable gas cylinders is the connection between the valve and the container body, for which there are specific regulations requiring special safety measures to be implemented to prevent the valve from becoming detached from the container body.

[0007] In fact, these regulations require the use of safety systems designed to prevent the removal and replacement of valves in order to prevent non-refillable cylinders from being used again.

[0008] In this regard, a first particularly popular known method consists in screwing the valve onto the container body using a high tightening torque and then applying a special anti-screwing adhesive to the valve.

[0009] However, this first solution does have some limitations, since the external fixation by adhesive is not sufficient to prevent the valve from being removed from the container body.

[0010] A second known method of operation consists in constructing a special valve, one end of which is adapted to break off in the event of an attempt to remove it, and remain within the body of the container, thereby preventing the insertion of another valve.

[0011] However, even the second method of operation does not guarantee that the cylinder cannot be reused, but it makes it possible to insert a new, shorter valve.

[0012] Furthermore, the above method is rather complicated to implement and is therefore even more inconvenient.

[0013] A third method of operation is to use a special safety system, the purpose of which is to prevent the valve from falling off the container body.

[0014] These systems involve the use of special blocking cups which are located externally to the valve and welded to the container body to ensure that the valve itself is blocked in place.

[0015] However, this third method also has significant disadvantages, in particular, the cup is placed on the outside of the cylinder and may therefore be damaged.

[0016] Another important issue arising from the use of the known solutions just discussed, in addition to what is required by current regulations, relates to the safety of the non-refillable gas cylinder in the event that the valve is removed intentionally or accidentally, for example in the event of damage during transport.

[0017] In fact, if there is gas in the cylinder, intentional or accidental removal of the valve can pose a great danger to people nearby, as they may be hit by the valve itself.

[0018] Furthermore, during the handling of gas cylinders, safety issues associated with known solutions become apparent.

[0019] Indeed, in these circumstances, implementation of the above-described embodiments intended to prevent the valve from being removed would result in the inability to evacuate any residual gas from the container body, thereby forcing the operator to cut the container body itself and, in doing so, expose themselves to considerable risk due to the sudden release of pressurized gas.

[0020] In addition to this, it is also important to note that intentional or accidental removal of the valve from the container body (and more generally, weakening of the connection seal therebetween) is also a significant safety risk for the user if there is residual gas in the container body.

[0021] Such weakening may occur, for example, due to impacts on the gas cylinder during the manufacturing process and / or transportation, which may expose the gas cylinder to abnormal stresses, which will significantly impair its safe use, thereby causing certain risks for users when using the gas cylinder.

[0022] Furthermore, the above-mentioned weakening may also be caused by attempting to destroy the non-refillable gas cylinder to replace its valve, thereby causing the pressurized gas to be suddenly released from the container body, posing a serious danger to the user.

[0023] From the considerations thus far it becomes clear that there is a particular need for a non-refillable gas cylinder in which the valve cannot be withdrawn from the container body and which is particularly safe to use even in the event of unintentional damage and vandalism. Summary of the invention

[0024] The main purpose of the present invention is to design a non-refillable gas cylinder that allows ensuring that the valve cannot be removed from the container body, thus preventing it from being replaced, while ensuring maximum safety in the event of damage or vandalism.

[0025] Another object of the present invention is to devise a non-refillable gas cylinder capable of overcoming the above-mentioned drawbacks of the prior art within the framework of a simple, rational, easy and effective to use and inexpensive solution.

[0026] The above-mentioned object is achieved by such a non-refillable gas cylinder having the features of claim 1 . BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Other features and advantages of the present invention will become more apparent from the description of a preferred but non-exclusive embodiment of a non-refillable gas cylinder, which is illustrated by way of schematic but non-limiting example in the accompanying drawings, in which:

[0028] Figure 1 is an overall axonometric view of a gas cylinder according to the present invention;

[0029] Figure 2 is a top axonometric view of a detail of a gas cylinder according to the invention;

[0030] Figure 3 is with Figure 2 an axonometric view of the same detail from below;

[0031] Figure 4 and Figure 5 2 is a front cross-sectional view of a gas cylinder according to the present invention in two different usage configurations. DETAILED DESCRIPTION

[0032] With particular reference to the drawings, reference numeral 1 generally designates a non-refillable gas cylinder.

[0033] Firstly, the non-refillable gas cylinder 1 comprises at least one hollow container body 2 adapted to contain pressurized gas and provided with at least one end 2a on which at least one port 3 for gas outflow is provided.

[0034] In particular, the container body 2 is substantially cylindrical.

[0035] The gas cylinder 1 then comprises at least one non-return valve 4 associated with the container body 2 , suitable for allowing gas to escape from the container body 2 , and provided with at least one threaded clamping portion 5 threadably connectable to the port 3 .

[0036] In fact, the clamping portion 5 is shaped to fit tightly into the port 3 and may fit securely therewith in such a way as to prevent unwanted gas leakage.

[0037] like Figure 1 , Figure 4 and Figure 5 As shown, the valve 4 comprises:

[0038] - at least one outer body 6 provided with a cavity 6a passing therethrough; and

[0039] at least one spool 7 fitted in a movable manner into the cavity 6a and adapted to allow / prevent the passage of gas through the cavity itself due to its own movement relative to the external body 6 .

[0040] Conveniently, the gas cylinder 1 comprises retaining means 8 associated with the container body 2 and adapted to prevent the valve 4 from being removed from the container body 2 .

[0041] In this case, the holding device 8 comprises at least one holding body 8 which is arranged inside the container body 2 at which the port 3 is located.

[0042] Arranging the retaining body 8 inside the container body 2 ensures that the retaining body cannot be touched or damaged by a user, which proves to be a particularly advantageous technical means for preventing the valve 4 from being removed from the container body 2 .

[0043] In particular, the retaining body 8 comprises at least one flexible portion 11 defining a passage hole 9 aligned with the port 3 along the axis A and adapted to receive a section of the valve 4 therein (see in this respect Figure 4 and Figure 5 ).

[0044] In other words, the valve 4 is arranged in a through-going manner within the passage hole 9 .

[0045] According to the invention, the valve 4 comprises at least one retaining end 10 having a significantly widened cross section and adapted to allow the valve 4 to be fitted into the container body 2 while preventing the valve 4 from being pulled out of the container body 2 .

[0046] According to the preferred embodiment shown in the figures, the retaining end 10 has a truncated cone-shaped configuration. However, different configurations of the retaining end 10, such as a truncated sphere or the like, cannot be excluded.

[0047] For this purpose, the holding end 10 has a converging portion in a direction away from the clamping portion 5 .

[0048] In fact, the increased thickness in the direction of movement away allows the flexible portion 11 to deform and the passage hole 9 to gradually expand, allowing the retaining end 10 to pass through the passage 9 and thus allowing the valve 4 to be assembled into the container body 2.

[0049] At the same time, this precise configuration prevents the reverse movement, ie, the retaining end 10 passes through the through hole 9 due to the valve 4 being assembled into the container body 2 .

[0050] Therefore, by the specific configuration of the retaining end 10, any attempt to remove the valve 4 from the container body 2 can be avoided, thereby complying with the aforementioned current regulations.

[0051] In more detail, it should be explained that the valve 4 is movable along the axis A between the following positions:

[0052] - Pressurized position, in which the clamping portion 5 is connected to the port 3 and the retaining end 10 is spaced apart from the flexible portion 11 ( Figure 4 );and

[0053] - a safety position, in which the clamping portion 5 is disengaged from the port 3 and the retaining end 10 is arranged to rest against the flexible portion 11 ( Figure 5 ).

[0054] During normal use of the gas cylinder 1 , the valve 4 is placed in the pressurized position, thereby preventing gas from escaping through the port 3 and allowing gas to be delivered only through the cavity 6 a due to the movement of the valve core 7 .

[0055] On the other hand, in the event of damage or attempted sabotage of the cylinder 1 , the valve 4 automatically places itself in a safe position, thereby remaining firmly anchored to the retaining body 8 and, in doing so, being substantially unable to move from the container body 2 .

[0056] According to the invention, the gas cylinder 1 comprises venting means 12 associated with the valve 4, suitable for allowing the gas contained in the container body 2 to escape when the valve 4 is in the safety position.

[0057] Advantageously, the venting device 12 comprises at least one non-threaded extension 13 formed on the valve 4 between the clamping portion 5 and the retaining end 10 , the diameter of which is smaller than the diameter of the clamping portion 5 .

[0058] Specifically, in the safe position, the non-threaded extension 13 is located where the port 3 is located and defines, together with the wall of the port 3, a peripheral space S suitable for allowing gas to escape from the container body 2 (in this regard, see Figure 5 ).

[0059] This approach proves to be particularly convenient, in particular in resolving the problems associated with the prior art discussed previously.

[0060] Indeed, as has been anticipated, damage or attempted sabotage of a gas cylinder 1 provided with a valve 4 may cause the valve to move from the pressurized position to the safe position.

[0061] In this case, if a certain amount of pressurized gas is present in the container body 2, this gas can effectively escape from the container body itself immediately by passing through the surrounding space S, thereby placing the container body 2 at ambient pressure.

[0062] In fact, in the event of a traffic accident and resulting damage to the gas cylinder 1, the technical means in question make it possible to prevent the valve 4 from detaching from the container body 2 due to the thrust exerted by the gas, thereby keeping the container body in a safe position to allow the gas to escape completely.

[0063] Similarly, in the event of an incomplete connection between the port 3 and the clamping portion 5, the venting device 12 also allows minimizing the risks to the user.

[0064] In fact, this situation also involves placing the valve 4 in the safety position, thereby allowing the gas to flow to the outside through the peripheral space S, so that the pressure of the container body 2 is substantially equal to the ambient pressure.

[0065] Finally, in terms of the processing cycle, the risk to service personnel can be minimized by simply placing the valve 4 in the safe position, thereby venting the gas contained in the container body 2 to the outside and returning the container body 2 to ambient pressure.

[0066] It should be noted that, according to the preferred embodiment shown in the figures, the threaded portion 13 is completely unthreaded and therefore has a completely "smooth" surface.

[0067] However, alternative embodiments are considered technically equivalent, in which the unthreaded extension 13 is partially provided with a thread interrupted by at least one longitudinal groove suitable for allowing the escape of gases.

[0068] Conveniently, at least one of the clamping portion 5 or the non-threaded extension 13 has a generally straight cylindrical configuration.

[0069] Preferably, both the clamping portion 5 and the non-threaded extension 13 have a generally straight cylindrical configuration.

[0070] Advantageously, if Figure 2 and Figure 3 As shown, the flexible portion 11 comprises a plurality of flexible elements 11 a having an elongated configuration and arranged about an axis A in a radial pattern relative to each other.

[0071] Specifically, the flexible portion 11 includes four flexible elements 11 a.

[0072] In fact, the use of four flexible elements 11a allows optimizing the production cycle of the gas cylinder 1 and its operating efficiency. However, it is easy to understand that the number of flexible elements 11a may be different, for example more.

[0073] More specifically, the flexible elements 11a are arranged at a substantially constant angular distance from each other.

[0074] In other words, the flexible elements 11 a are arranged at 90° to each other.

[0075] The flexibility of the flexible elements 11 a allows them to expand elastically and thus enlarge the passage hole 9 to allow the passage of the retaining end 10 during the insertion of the valve 4 into the container body 2 .

[0076] Advantageously, the elastic element 11 a is made of a metal material.

[0077] Particularly, the elastic element 11 a is made of stainless steel.

[0078] More specifically, the flexible element 11a is made of ferritic stainless steel.

[0079] Specifically, the elastic element 11a is made of Aisi430.

[0080] The selection of this material is very advantageous, since it gives good resilience to the elastic element 11 a and reduces oxidation triggering due to the insertion of the retaining end 10 into the passage hole 9 .

[0081] However, it cannot be excluded that a different material is used to make the flexible element 11 a , which nevertheless allows sufficient springback due to the complete insertion of the valve 4 .

[0082] Conveniently, the retaining body 8 comprises at least one coupling portion 14 associated with the flexible portion 11 and adapted to enable the retaining body 8 to be connected to the end portion 2a (see Figure 2 and Figure 3 ).

[0083] Specifically, the coupling portion 14 includes at least one base surface 14 a and a plurality of welding protrusions 14 b formed on the base surface 14 a and arranged around the axis A in a radial pattern.

[0084] Specifically, the coupling portion 14 includes four welding protrusions 14b.

[0085] As can be seen in the preceding figures, the welding projections 14 b are arranged at a constant angular distance from one another.

[0086] The presence of the welding projection 14b allows the retaining body 8 to be connected to the end portion 2a by projection welding, thereby forming a particularly strong and durable connection between the two.

[0087] It has been established in practice that the described invention achieves the intended purposes.

[0088] In particular, emphasis is to be placed on the fact that the particular arrangement of the retaining means ensures that it is impossible to damage them and therefore to remove the valve from the container body.

[0089] Furthermore, the special means of providing the venting device allows the gaseous contents of the container body to be easily and effectively removed, thereby minimising the risk to the user and operators involved in the disposal of the gas cylinder.

Claims

1. A non-refillable gas cylinder (1), comprising: - at least one hollow container body (2) suitable for containing a pressurized gas and provided with at least one end (2a) on which at least one port (3) for the gas outlet is provided; - at least one non-return valve (4) associated with the container body (2) and adapted to allow gas to escape from the container body (2) and provided with at least one threaded clamping portion (5) capable of being threadedly connected to the port (3); - retaining means (8) associated with the container body (2) and suitable for preventing the valve (4) from being removed from the container body (2); Features: - the retaining device (8) comprises at least one retaining body (8) arranged inside the container body (2) where the port (3) is located and comprising at least one flexible portion (11), the at least one flexible portion (11) defining a passage hole (9) aligned with the port (3) along the axis (A) and suitable for accommodating a section of the valve (4) therein; - the valve (4) comprises at least one retaining end (10) of a generally widened configuration, the at least one retaining end (10) being adapted to allow the valve (4) to be fitted into the container body (2) and to prevent the valve (4) from being pulled out of the container body (2), the valve (4) being movable along the axis (A) between a pressurized position and a safety position, wherein in the pressurized position the clamping portion (5) is connected to the port (3) and the retaining end (10) is spaced apart from the flexible portion (11); and wherein in the safety position the clamping portion (5) is disengaged from the port (3) and the retaining end (10) is arranged to stop against the flexible portion (11); and - the gas cylinder (1) comprises a venting device (12) suitable for allowing the gas contained in the container body (2) to escape when the valve (4) is in the safety position.

2. The gas cylinder (1) according to claim 1, characterized in that: - the venting device (12) comprises at least one non-threaded extension (13), which is formed on the valve (4) between the clamping part (5) and the retaining end (10), and the diameter of the at least one non-threaded extension (13) is smaller than the diameter of the clamping part (5); and - In the safety position, the non-threaded extension (13) is located where the port (3) is located and defines, together with the wall of the port (3), a peripheral space (S) suitable for allowing gas to escape from the container body (2).

3. Gas cylinder (1) according to one or more of the preceding claims, characterized in that The retaining end (10) has a convergent portion in a direction away from the clamping portion (5).

4. Gas cylinder (1) according to one or more of the preceding claims, characterized in that The retaining end (10) has a generally frustoconical configuration.

5. Gas cylinder (1) according to one or more of the preceding claims, characterized in that The flexible portion (11) comprises a plurality of flexible elements (11a) having an elongated configuration and arranged in a radial pattern relative to each other around the axis (A).

6. The gas cylinder (1) according to claim 5, characterized in that The gas cylinder (1) comprises four flexible elements (11a).

7. The gas cylinder (1) according to claim 4 or 5, characterized in that The flexible elements (11a) are arranged at a substantially constant angular distance from each other.

8. Gas cylinder (1) according to one or more of the preceding claims, characterized in that The flexible element (11a) is made of metal material.

9. Gas cylinder (1) according to one or more of the preceding claims, characterized in that The retaining body (8) comprises at least one coupling portion (14) associated with the flexible portion (11) and adapted to enable the retaining body (8) to be connected to the end portion (2a).

10. The gas cylinder (1) according to claim 9, characterized in that The coupling portion (14) includes at least one base surface (14a) associated with the flexible element (11a) and a plurality of welding protrusions (14b), the plurality of welding protrusions (14b) being formed on the base surface (14a) and arranged in a radial pattern around the axis (A).

Images