WO1986000869A1

WO1986000869A1 - Arrangement for a combined tank cover and emptying tube

Info

Publication number: WO1986000869A1
Application number: PCT/SE1984/000264
Authority: WO
Inventors: Bengt Petersson
Original assignee: N.P.-New Products Nordinvent Investment Aktiebolag
Priority date: 1984-07-18
Filing date: 1984-07-18
Publication date: 1986-02-13
Also published as: EP0188417A1

Abstract

Arrangement for such combined sealing covers and emptying tubes as are encountered in particular in fuel tanks and which exhibit a cover (1) with an attachment part in the form of a thread (5, 6) extending towards the middle of the cover from either end of same, in conjunction with which an emptying tube (8) or similar extends from the cover in one direction. The arrangement is intended to be attached to an emptying stub (11) in such a way that the tube (8) either faces inwards into the tank or similar (12) on which the emptying stub is situated, or outwards away from same. In the first case a sealing plug (2) is attached to the attachment part (6) which faces outwards in this position. The other attachment part (5) is attached to the stub (11). In the second position the first-mentioned attachment part (6) is attached to the stub whilst the plug (2) is removed. Connected to the cover (1) is a device (3) which is capable of being displaced between two positions, a first position in which the device covers the plug (2) in such a way that, when it is attached to the first-mentioned attachment part (6), it is prevented from being removed, and a second position (2, 3) in which the device is displaced in such a way that the removal of the plug from the attachment part (6) is possible. The device is so arranged as to be forced into its first position when the arrangement is in said sealing position on the stub (11) with its second attachment part (5), and in such a way as to be free to adopt its second position when the arrangement is at least partially removed from the stub (11) with the second attachment part (5).

Description

Arrangement for a combined tank cover and emptying tube

Technical field:

The present invention relates to a cover arrangement of the combined sealing cover and emptying tube type in particular in fuel tanks which exhibit a cover with an attachment part in the form of a thread extending towards the middle of the cover from either end of same, in conjunction with which an emptying tube or similar extends from the cover in one direction, with the arrangement intended to be attached to an emptying stub in such a way that the tube either faces inwards into the tank or similar on which the emptying stub is situated, or outwards away from same in the first case with a sealing plug attached to the attachment part which faces outwards in this position and the second attachment part attached to the stub, whilst in the second position the first— entioned attachment part is attached to the stub whilst the plug is removed.

Background:

There is in existence a common type of combined sealing cover and emptying tube for fuel tanks such as spare fuel cans for vehicles. In the position for sealing the tank an emptying tube faces inwards into the tank. In the position for emptying the cover is unscrewed and inverted. Once a plug has been removed, the cover can be screwed on with the emptying tube facing outwards. The arrangement functions well provided that, when a full tank is to be sealed, the plug is first screwed into the lid, whereupon the tube is introduced into the tank and the cover is screwed securely onto the tank emptying stub. The reverse procedure is adopted for unscrewing. It is thus necessary to unscrew the cover from the tank stub first, without removing the plug beforehand.

Technical problem:

By this procedure an air cushion will be produced inside the emptying tube when the arrangement for sealing the tank is

O PI applied. In conjunction with unscrewing the positive pressure which is usually produced inside tanks containing a volatile fluid such as petrol will escape at the edges of the cover when this is released, and the outward flow will then consist of gas from the space situated at the very top of the tank next to the emptying stub. If, however, the plug were to be unscrewed first, then the risk would be considerable of the positive pressure causing the fluid to be forced out via the inward—facing emptying tube, with the result that it will gush out over the person performing the unscrewing operation. If, furthermore, the plug was not screwed down when the cover was screwed down, the inward—facing tube will be full of fuel, and a considerable volume may gush out_.. Several serious accidents have occurred for the reasons outlined above, as a result of a fairly large quantity of fuel having gushed out and ignited. In spite of this, however, the arrangement is in widespread use, since attempts to invent an alternative and more reliable type o arrangement have until now failed to come up with an equally usable and convenient design.

The object of the invention is to make available an arrangement for the aforementioned type of combined sealing cover and emptying tube which makes it impossible to follow the wrong sequence when assembling and dismantling the cover, so that the aforementioned risk of fluid gushing out from the tank is eliminated.

The solution:

The aforementioned object is achieved by means of the arrangement in accordance with the invention, which is characterized in that there is connected to the cover a device which is capable of being displaced between two positions, a first position in which the device covers the plug in such a way that, when it is attached to the first-mentioned attachment point, it is prevented from being removed, and a second position in which the device is displaced in such a way that the removal of the plug from the attachment part is possible, in which case the device is so arranged as to be forced into its first position when the

"_BUREA

O PI WIPO arrangement is in said sealing position on the stub with its second attachment part, and in such a way as to be free to adopt its second position when the arrangement is at least partially removed from the stub with the second attachment part.

Brief description of drawings:

An embodiment of the invention is illustrated in the accompanying drawings. Figs. 1—3 show a sealing cover in accordance with the invention in three different positions; in Fig. 1 it is shown screwed down for the purpose of sealing a tank, in Fig. 2 it is shown screwed down for the purpose of emptying fluid from the tank, and in Fig. 3 it is shown in an outer position in conjunction with screwing down or unscrewing.

Best mode of carrying out the invention:

The previously disclosed design consists of two parts, a double nut 1 and a plug 2. The third part illustrated, a sleeve 3, is ignored initially because it does not belong to the previously disclosed design described below.

The double nut 1 consists of a circular body 4 into which there extends from either side a female thread 5 and 6 respectively. Between the threads is an inward—extending flange 7.. From the flange there runs a tube 8 which extends out from the part 4 on that side on which the female thread 5 is situated, A space is left clear, however, between the thread and the tube 8. The body 4 and the tube 8 are illustrated as a single piece in the Figures. For production reasons, however, it is usual for each part to be manufactured as a separte component for subsequent joining together.

The plug 2 is provided with a screwed thread 9, which fits in the thread 6, which is identical to the thread 5.

The arrangement is commonly found in spare fuel cans for vehicles. As a rule the fuel filler pipe on the vehicle is on a vertical surface, and it is accordingly not possible to pour fuel directly from the emptying stub of a spare can; a tube which can be introduced into the vehicle tank opening is required.

With the arrangement in its sealed position the thread 5 in accordance with Fig. 1 is screwed down on the external thread 10 of an emptying stub 11 on an only partially illustrated tank 12. The tube 8 thus extends into the tank 12 and, if it is full, down into its contents. The outlet via the double nut 1 is closed by means of the plug 2, which is screwed into the outward—facing thread 6 of the double nut in that position.

In the emptying position in accordance with Fig. 2 the plug 2 is removed, and the thread 6 of the double nut 1 is screwed down onto the tank stub 11.. The tube 8 extends outwards in this case and can be used for the aforementioned emptying of the tank 12, In this position the plug 2 thus has no function.

The nature of the invention is such that the aforementioned sleeve 3 is on the outside of the arrangement. This sleeve is capable of displacement axially on the double nut 1, but is incapable of rotation in relation to same, Locking in the direction of rotation is achieved by the double nut being provided on its outside with ribs 13. The sleeve 3 is provided with corresponding grooves 14, As illustrated in Fig. 1, the length and the possible displacement position of the sleeve 3 are so adapted in relation to the rest of the arrangement that it is forced outwards when the sealing arrangement is applied and for as Cong as the outer priphery of the plug 2 is concealed.

The function of the arrangement in accordance with the invention, which is to determine the sequence when screwing down and unscrewing, is satisfied in the manner which is evident from the following. The aforementioned sequence must, therefore, be the following: unscrewing of the entire cover with the plug remaining in place, and screwing down the entire cover with the plug screwed in before beginning to screw down the double nut.

Unscrewing from the position illustrated in Fig. 1 will be described first.. In this position the sleeve 3 is forced outwards by the wall of the tank and covers the periphery of the plug 2. As the outer, axial surface of the plug 2 does not provide any grip, it is thus impossible to start unscrewing by removing the plug 2. The entire arrangement must first be unscrewed by gripping around

OMPI the non—rotatable sleeve 3 for such a distance that the sleeve can be pushed down from the plug 2, so that this is exposed; see Fig. 3. By the appropriate adaptation of the length of the sleeve, this will be unable to occur before the screwed connection has been unscrewed to such an extent that the positive pressure has been released.

The opposite situation is applicable to screwing down. If the screwing down operation were to be begun by screwing in the double nut 1 without first having screwed in the plug 2, one would find when the screwing down operation was complete that the plug cannot be screwed in because of the recess formed by the sleeve 3, which is now being forced outwards by the tank 1 _. One is thus obliged to screw down the plug securely before starting to screw down the arrangement.

The arrangement has been described primarily in conjunction with fuel tanks. These are also a natural area of application for the invention, since as spare fuel cans they call for an emptying tube which should not be a separate arrangement, but which should accompany the can. At the same time the situation exists that positive pressure is easily formed inside the storage space, and that gushing out of the fluid can result in severe personal injury or at least considerable discomfort. However, this does not exclude the possibility that the arrangement can be used in other contexts, where identical needs and similar risks are encountered.

It is possible to modify the arrangement within the scope of the following Patent Claims. A bayonet connection or some form of snap—in lock, for example, may thus be used instead of the threads. The protective device in accordance with the invention, being the sleeve 3 in this embodiment, must, in order for the intended function to be achieved, be capable of being displaced between a position in which it will prevent removal of the plug and a position in which the plug is accessible. This need not take place as a result of linear displacement, but in the case of a sleeve it may, for example, be threaded and executed with two outer stop positions, so that it can be moved between them by being rotated. It is also possible to depart entirely from the

design as a sleeve and instead to provide a pivoting cap, for example, which must be pivoted up over the plug when the arrangement is attached, and which may be pivoted out of the way when the arrangement is unscrewed.^"

OMPI

Claims

Patent Claims:

1. Arrangement for such combined sealing covers and emptying tubes as are encountered in particular in fuel tanks and which exhibit a cover (1) with an attachment part in the form of a thread (5, 6) extending towards the middle of the cover from either end of same, in conjunction with which an emptying tube (8) or similar extends from the cover in one direction, with the arrangement intended to be attached to an emptying stub (11) in such a way that the tube (8) either faces inwards into the tank or similar (12) on which the -emptying stub is situated, or outwards away from same, in the first case with a sealing plug (2) attached to the attachment part (6) which faces outwards in this position and the second attachment part (5) attached to the stub (11), whilst in the second position the first— entioned attachment part (6) is attached to the stub whilst the plug (2) is removed, c h a r a c t e r i z e d in that to the cover (1) there is connected a device (3) which is capable of being displaced between two positions, a first position (Fig. 1) in which the device covers the plug (2) in such a way that, when it is attached to the first—mentioned attachment part (6), it is prevented from being removed, and a second position (2, 3) in which the device is displaced in such a way that the removal of the plug from the attachment part (6) is possible, in which case the device is so arranged as to be forced into its first position when the arrangement is in said sealing position on the stub (11) with its second attachment part (5), and in such a way as to be free to adopt its second position when the arrangement is at least partially removed from the stub (11) with the second attachment part (5).

2. Arrangement according to Patent Claim 1, in which the attachment parts consist of rotating attachments such as threads (5, 6⁾ or bayonet connections, c h a r a c t e r i z e d in that the device consists of an axial sleeve (3) so arranged as to be capable of displacement but incapable of rotation on the cover executed as a double nut (1), said sleeve being so arranged with regard to its length and its capacity for displacement as to be

CiVFPI WIPO forced outwards with the device in its first position towards the outer end of the double nut (1.) by means of a closure extending outwards from the stub (11), in such a way that a recessed position is formed from the plug (2), which, when it is placed on the outward—facing attachment part (6) of the double nut,- is incapable of being removed and inserted for as long as the sleeve is prevented from being displaced from the position of the plug, whereas, when the double nut (1) is at least partially removed from the stub (11) with its second attachment part (5), the sleeve is no longer prevented from being displaced from the position of the plug, so that it is accessible.