EP2166272A1

EP2166272A1 - Container, in particular combustion gas cylinder, provided with a check circuit to detect damage

Info

Publication number: EP2166272A1
Application number: EP08425611A
Authority: EP
Inventors: Nicola Pisarri
Original assignee: Fiat Group Automobiles SpA
Current assignee: FCA Italy SpA
Priority date: 2008-09-19
Filing date: 2008-09-19
Publication date: 2010-03-24

Abstract

A container (1), in particular a combustion gas cylinder, is provided with a shell (2) and with an adhesive sheet (10) attached to the outer surface (2) of the shell (2); the adhesive sheet (10) carries a check circuit usable to verify whether the container (1) has suffered any damage.

Description

The present invention relates to a container, in particular a combustion gas cylinder, provided with a check circuit to verify the presence of any damage.
Japanese patent application with publication number JP 10-030797 describes a combustion gas cylinder provided with an outer reinforcement layer comprising resin, in which a check circuit is embedded. Said check circuit comprises a series of wires wound in a spiral on the outside of the cylinder and is used to determine the presence of any damage, by verifying an interruption in the check circuit due to a break in the wires.
Said solution is not entirely satisfactory, in that it is somewhat complex to produce, in particular in terms of the positioning of the wires during the forming of the reinforcement layer, and involves relatively long production times, especially due to the processes of applying and hardening the resin. Moreover, this solution cannot be applied to cylinders that have already been placed on the market.
The purpose of the present invention is to produce a container, in particular a combustion gas cylinder, provided with a check circuit to verify the presence of any damage, which overcomes the problems described above in a simple and cost-effective manner.
According to the present invention a container is produced, in particular a combustion gas cylinder, comprising:

a shell delimiting a volume for a fluid;
an outer layer arranged over said shell;
a check circuit carried by said outer layer and usable to verify the presence of any damage to the container;

characterized in that

In order to better understand the present invention, a non-limiting preferred embodiment thereof will now be described by way of example with reference to the accompanying drawings, in which:

figure 1 shows a preferred embodiment of the container, in particular a combustion gas cylinder, according to the present invention;
figure 2 is a plan view of an adhesive sheet that forms part of the container of figure 1; and
figure 3 is a cross-section on an enlarged scale of a portion of the sheet of figure 2.

In figure 1, number 1 indicates a container comprising a shell 2, which is made from a composite material, preferably from carbon fiber reinforced plastic, and defines an internal volume for a fluid under pressure. In particular, the shell 2 comprises an intermediate cylindrical portion 4 and two opposing dome-shaped extremities 5, 6. Clearly, the shell 2 could be differently shaped, for example it could be toroidal shaped. The shell 2 can consist of a single layer or of a multi-layer element.
In the particular example described herein, the container 1 defines a tank or cylinder of combustion gas for a vehicle and comprises a valve assembly 7 arranged on the extremity 6 to control the supply of the combustion gas and/or the pressure inside the shell 2.
The outer surface of the shell 2 is indicated by number 8 and is at least partially coated with a sheet 10, which is made from plastic material and is of an appropriate thickness and shape so as to remain entirely in contact with the surface 8 without any folds. For example, the thickness of the sheet 10 is approximately 0.05 mm.
With reference to figure 2, the sheet 10 comprises a substantially rectangular intermediate portion 13, attached to the portion 4, and two sets of lobes having a substantially trapezoidal shape, arranged along the sides of the portion 13 and attached, respectively, to the extremities 5 and 6.
With reference to figure 3, (in which the various components are not illustrated to scale for the sake of clarity), the surface of the sheet 10 that is in contact with the surface 8 is indicated by number 15 and is provided with an adhesive 16 capable of maintaining the sheet 10 attached to the surface 8 during use even in the presence of dust and/or external moisture.
The sheet 10 carries a wire 18, which is made of an electrically conductive material and is arranged in a coil and in a fixed position on substantially the entire surface 17 which is opposite the surface 15. In the particular example that is illustrated, the wire 18 has a relatively small cross section (approximately 0.01 mm² or less) so as to break in the event of accidental contact, for example a rectangular cross-section with a width of approx 0.1 mm (figure 3), and comprises a plurality of rectilinear portions 19 linked to one another and spaced approximately 5 mm apart.
The wire 18 is preferably applied to the sheet 10 by means of a screen printing process or is defined by conductive paint applied to the sheet 10 by means of a printing process.
The ends of the wire 18 are defined by electric terminals inserted in a connector 20 made from plastic material, which is carried by the sheet 10 in a fixed position, for example co-pressed on the sheet 10, protrudes from the surface 17, and with the wire 18 defines a check circuit connectable to a sensing circuit that is not illustrated and not described in detail.
The sensing circuit is conveniently installed on the vehicle and is capable of verifying the continuity of the wire 18 at the two wire terminals, and of emitting a relative fault signal in case of discontinuity, to warn of possible damage to the shell 2.
If the cylinder 1 suffers an impact or abrasion such as to cut the coiled wire 18 at any point, the electric continuity is interrupted and the sensing circuit signals the fault, for example in the form of an indicator lamp that lights up on the instrument panel of the vehicle or in the form of an acoustic signal. Upon noticing the fault, the driver of the vehicle must go to the service station to check whether the shell 2 has actually been damaged.
If the inspection at the service station finds any damage to the shell 2, in particular to the reinforcing fibers of the composite material, the cylinder 1 must be replaced. If the shell 2 is found to be intact, the sheet 10 is simply replaced.
In theory the entire surface 8 can be covered, but the sheet 10 is preferably arranged in correspondence with the most delicate parts of the shell 2 and/or the parts that are most likely to be subject to impacts or abrasions.
From the above description it is apparent that the sheet 10 enables the driver to be warned immediately of an impact or abrasion, with possible damage to the cylinder 1, without having to remove the cylinder 1 from the vehicle. Moreover, the sheet 10 makes it possible and extremely simple to check that no damage has been caused while installing the cylinder 1 during assembly of the vehicle. If a fault signal is present, the cylinder 1 is disassembled in order to verify the integrity of the shell 2 immediately after assembly. If no defects are found, the sheet 10 is replaced before re-assembling the cylinder 1 in the vehicle.
The sheet 10 is self-adhesive so that it can be attached to the surface 8 easily and quickly. The sheet 10 can be attached and removed by hand, without the need for extremely precise positioning on the surface 8. Moreover, the sheet 10 can also be attached to existing cylinders or containers, without the need for any modifications.
Lastly, it is clear that modifications and variations may be made to the container or cylinder 1 described and illustrated herein without departing from the scope of the present invention, as set forth in the claims.
For improved coverage of the surface 17 by the wire 18, the wire 18 could have a different shape or follow a different path to those described by way of example, for instance it could have sinusoidal portions instead of rectilinear ones.
The wire 18 could be made from any other material suitable to determine the continuity between the two wire terminals, for example it could be an optic fiber; and/or it could be fixed to the sheet 10 using a process other than screen printing or printing.
Instead of a single wire 18, the sheet 10 could carry a plurality of wires or check circuits arranged parallel to one another and in given areas of the surface 17: by determining which wire is broken, this would indicate which portion of the shell 2 should be checked to enable a more rapid verification of any damage to the cylinder 1. Alternatively, a set of sheets 10 could be arranged on the surface 8, with respective check circuits, preferably parallel to one another, instead of having a single sheet 10.

Claims

Container (1), in particular a combustion gas cylinder, comprising:
- a shell (2) delimiting a volume for a fluid;

- an outer layer (10) arranged over said shell (2);

- a check circuit carried by said outer layer (10) and usable to verify the presence of any damage to the container (1);
characterized in that said outer layer is a sheet (10) having an adhesive surface (15) attached to an outer surface (8) of said shell (2).
Container according to claim 1, characterized in that said check circuit comprises an electrically conductive wire (18) arranged on the surface (17) opposite said adhesive surface (15).
Container according to claim 2, characterized in that said electrically conductive wire (18) is applied to said sheet (10) by means of a screen printing process.
Container according to claim 2, characterized in that said electrically conductive wire (18) is obtained by printing conductive paint onto said sheet (10).
Container according to any one of the previous claims, characterized in that said check circuit comprises a connector (20) carried in a fixed position by said sheet (10) on the surface opposite said adhesive surface (15).