EP0222736B1 - Bayonet lock for a container - Google Patents

Description

The invention relates to a bayonet closure for containers with a ring rigidly connected to the edge of the container opening and a form-fitable engagement with the ring by radial claws and recesses for pressure-tight closing of the container, the lid being a fitting for the discharge from below Has pressure in the container.

Bayonet closures for containers are used successfully in many areas. In connection with fire extinguishers, it has generally been preferred for safety reasons to screw a lid onto the edge of the container in order to prevent the lid from opening quickly. Disadvantages of such screw closures, however, are the fact that the containers sealed in this way generally only fully seal when internal pressure occurs and that, in the event of an existing residual pressure inside the container, the threads are pressed against each other when screwed on to the extent that a more secure one Pressure equalization is not guaranteed. A screw cap can therefore still lead to an unintentional, sudden lifting after leaving the last thread if there is residual pressure inside.

From US-A-2 665 028 a closure for tanks or similar containers has become known, wherein a claw engaging over the closure cap engages in recesses on the outer circumference of a pipe socket screwed into the container opening and the cover is held in the recesses by rotating the claw. An integrated fitting for dispensing the contents of the container is not provided with this closure.

The invention now aims to develop a bayonet lock of the type mentioned, as it is particularly for devices which can be put under pressure similar to a fire extinguisher and which allow the contents of the container to be discharged under pressure via a corresponding fitting, so that the container is quick and safe can be opened to enable a new filling and that the container ensures complete tightness in the unpressurized state as well as in a state in which the container contents are pressurized. This is particularly necessary in connection with container contents that are harmful to health or otherwise questionable for storage and transport. To achieve this object, the bayonet lock according to the invention essentially consists in that the radial recesses are formed in a graduated manner in the circumferential direction, the graduations being spaced apart in the axial direction of the closure, that the ring rigidly connected to the edge of the opening has an internal, cylindrical or The interior of the container, which is tapered, is limited to the fact that a tubular extension that dips into the surface when it closes is connected to the lid, that the tubular extension has a circumferential seal, that the ring has a radial relief bore and / or groove, and that the seal when the claws engage in the first stage of the recesses via the relief bore and / or groove, a pressure-relieving connection with the interior of the container is released and in the second stage of the recesses the relief bore and / or groove is closed pressure-tight. The fact that, differently from the known designs with screw locks, a bayonet lock is selected, it is first ensured that the opening and closing can proceed relatively quickly. In order to enable safe refilling, the design is such that the closure lid can first be brought into a first position without any significant effort, from which it is located If there is a residual pressure, it automatically performs a short stroke to the outside, and at the same time this stroke allows pressure compensation in the radial direction to the outside, so that any pressure fluid or pressure gases still present can flow out laterally. Only in a further sequence is the lid completely released in the event of further rotation due to the stepped and axially spaced design of the recesses, in order to ensure in the first step that the pressure equalization actually takes place sufficiently quickly and safely that the design is made in such a way that that a tubular extension, which dips into the interior of the container and interacts with an inner, cylindrical or conically tapering lateral surface, has a circumferential seal which, when the cover is lifted up to the first stage, has a radial relief bore and / or - only releases. In this state, the pressure equalization is thus achieved, this configuration at the same time ensuring that the container is immediately tightly closed even without pressure by the circumferential seal when the lid is closed. In order to ensure the effect of this seal running in the circumferential direction even with increasing wear of the seal, the inner lateral surface into which the tubular extension with the seal is to be immersed is formed by a cylindrical or a conical surface tapering towards the interior of the container. In the case of a conically tapered lateral surface, the closing stroke simultaneously ensures that the seal is pressed appropriately against the surrounding wall and that the tightness is ensured in the unpressurized state as well as in the state under pressure.

In a particularly simple manner, the cover can have inwardly jumping claws and the ring on its outer circumference can have the stepped recesses.

In order to secure the closed position of the lid and to counteract an unintentional opening of the lid, the design is advantageously made such that the lid carries a spring-loaded releasable radial locking pin which can be locked in the closed position with a recess in the ring. In a particularly simple manner, the recess of the ring for locking the locking pin can be formed by the relief bore and / or groove.

In order to ensure that the cover is only ever placed in a correct position, in which a corresponding locking also occurs after a short rotation, the design is advantageously made such that the claws of the cover are arranged at uneven central angles distributed over the circumference, wherein preferably in the attachment position of the cover for pivoting the same into a first position corresponding to the first step of the recesses on the outer circumference of the ring, an inclined surface, preferably with generators pointing in the radial direction, is aligned with the locking pin in the axial direction, and the locking pin is supported on the outside of the ring when the cover is turned. In this way, when attaching the cover, which is only possible in a certain position due to the distribution of the claws in the unequal central angle over the circumference, it is ensured that the locking pin is pressed outwards immediately after attachment and only when the locking position has been reached Position of the locking pin snaps into the designated recess.

In order to accelerate the pressure compensation after lifting the cover to the first step of the recess, the cover preferably has at least one further radial relief bore above the level of the claws. As soon as the lid is lifted, the circumferential seal connected to the tubular extension, the relief bore or relieving relief groove, the medium escaping via this relief bore or relief groove can escape unhindered via the radial bore of the cover, the direction in which the medium escapes also being predetermined by the relief bore.

The training is preferably such that three claws and stepped grooves or recesses are provided.

The invention is explained in more detail below with reference to an embodiment shown in the drawing. 1 shows a bayonet catch according to the invention for use in a fire extinguisher; 2 shows the ring rigidly connected to the container in plan view and FIG. 3, 4, 5 sections along the lines III-III, IV-IV, V-V of FIG. 2; 6 the ring in the rolled-up state; 7 shows the cover of the closure in plan view; 8 shows a section along the line VIII-VIII of FIG. 7 and FIG. 9 shows a section along the line IX-IX of FIG. 7 with the shoulder inserted.

In Figure 1, a bayonet lock 1 is used for the pressure-tight closure of a fire extinguisher 2. The lid 3 of the closure 1 has a fitting 4 for dispensing the pressurized container contents. A radial locking pin 5 is arranged on the outer circumference of the cover 3, which is biased by a leaf spring 6 via screws 7 and is intended to prevent the container from being opened unintentionally.

2 shows the ring 8 rigidly connected to the edge of the opening of the container 2, which together with the cover 3 forms the bayonet catch 1. On the ring 8 radial recesses 9 are arranged, which are designed in a stepped manner, as indicated by the dashed lines. In addition, the ring 8 has a relief groove 10 which is arranged such that when the cover 3 engages with the ring 8 in the first stage of the recesses 9, the relief groove 10 is released and is only sealingly ground in the second stage. In addition, an inclined surface 11 is arranged on the ring 8 in the attachment position of the cover 3 on the ring 8 in the axial direction in alignment with the locking pin 5. The relief groove 10 also serves as a latching opening for the locking pin 5 when the cover 3 is rotated in the second stage of the recesses 9 until they stop. for additional centering of the cover 3 in the ring 8, the ring 8 has a stepped surface 12 on its inner circumference.

3, 4, 5, 6, the reference numerals of FIG. 2 have been retained. 3 clearly shows the first step of a recess 9, a representation having been chosen in which the cover 3 can no longer be removed only by movement in the axial direction. To facilitate the rigid connection of the ring 8 to the container 2, the ring 8 also has a stepped surface 13 on its underside. The opening diameter a on the top of the ring 8 exceeds the diameter b on its underside and this results in a conical surface tapering towards the inside of the container as the inner circumferential surface 14 of the ring 8. FIG. 4 shows a second step of a recess 9 and the inclined surface arranged above it 11. FIG. 5 shows a section through the relief groove 10 of the ring 8, the depth c of which is in any case less than the distance d from the upper edge of the second step of the recess 9 to the upper edge of the ring 8, in order to provide a sealing closure when the cover engages 3 to ensure in the second stage of the recesses 9 via a seal arranged on the cover, which is pressed against the outer surface 14 of the ring 8. In the rolled-up representation of the ring 8 in FIG. 6, the stepped recesses 9 for receiving the claws of the cover 3 can be clearly seen. The unequal distance e, f between the Recesses corresponds to the uneven center angles of the claws arranged on the cover. The height of the steps of the recesses 9 is designated g.

In Figure 7 claws 15 are indicated by dashed lines on the cover 3, which can be positively engaged with the recesses 9 of the ring 8. The claws 15 are arranged in unequal center angles ∝ and ß on the circumference of the cover 3, which ensures that the cover 3 can only be placed in one position in the recesses 9 provided on the ring 8, also at unequal intervals e, f. 16 denotes the hole for receiving the locking pin 5 and 17 holes for fixing the screws 7 for biasing the locking pin via the leaf spring. The central opening 18 of the lid 3 serves to receive a tubular extension which projects into the interior of the container.

8 shows a claw 15 jumping inwards on the cover 3, the height h of which is less than or equal to the height g of a step of the recesses 9. 16 in turn denotes the bore for the implementation of the locking pin 5.

FIG. 9 shows the lid 3 with the tubular extension 19 which projects into the interior of the container when the lid is closed. The stepped surface 20 of the extension 19 allows with the stepped surface 12 of the ring 8 a precise centering of the cover in the ring 8. By means of the seal 21, which can be pressed onto the conical outer surface 14 of the ring 8, the claws 15 in during the positive engagement the second stage of the recesses 9 reaches a sealing closure of the container 2. The distance k of the seal 21 from the lower edge of the cover 3 must be selected larger than the depth c of the relief groove 10 in order to ensure a secure closure. However, the distance k must be less than c and g in order to raise the cover 3 from the second to the first step of the recesses 9, these Shifting movement corresponds exactly to the step height g, to ensure an at least partial opening of the relief groove 10 and in this way to enable any pressure equalization.

Claims (8)

1. A bayonet closure for containers (2) with a ring (8) rigidly connected to the rim of the opening of the container and with a lid (3) capable of being brought via radial claws (15) and recesses (9) into key-fit engagement with the ring (8) for the pressure-tight closure of the container (2), wherein the lid (3) has an instrument (4) for the extraction of the pressurised contents of the container, characterised in that the radial recesses (9) are formed in a circumferentially stepped manner with the steps spaced in the axial direction of the closure; in that the ring (8) rigidly connected to the rim of the opening of the container forms the boundary of an internally-disposed mantle surface (14) which is cylindrical or which extends conically towards the interior of the container; that a tubular extension (19) is connected to the lid (3) and dips on closure into the mantle surface (14); that the tubular extension (19) has a circumferentially extending seal (21); that the ring (8) has a radial relief bore and/or nut (10) and that on engagement of the claws (15) into the first step of the recesses (9) the seal (21) uncovers a pressure-relieving connection with the interior of the container via the relief bore and/or nut (10) and pressure-tightly seals the relief bore and/or nut (10) in the second step of the recesses (9).
2. A bayonet closure according to claim 1, characterised in that the lid (3) has inwardly projecting claws (15) and the ring (8) has the recesses (9) on its outer periphery.
3. A bayonet closure according to claim 1 or 2, characterised in that the lid (3) carries a spring-loaded, releasable radial locking pin (5) which can be latched in the closure position into a recess of the ring (8).
4. A bayonet closure according to claim 3, characterised in that the recess of the ring (8) is formed for latching the locking pin (5) from the relief bore and/or nut (10).
5. A bayonet closure according to one of claims 2 to 4, characterised in that the claws (15) of the lid (3) are distributed over the periphery in unequal central angles (α,β).
6. A bayonet closure according to one of claims 3 to 5, characterised in that in the application position of the lid (3), an inclined surface (11), preferably with a radially extending generatrix, is arranged in axial alignment with the locking pin (5), for tilting the lid into a first position on the outer periphery of the ring (8) corresponding to the first step of the recesses; and that the locking pin (5) is supported on the outside of the ring (8) on annular displacement of the lid (3).
7. A bayonet closure according to one of claims 2 to 6, characterised in that above the plane of the claws (5) the lid (3) has at least one further radial relief bore.
8. A bayonet closure according to one of claims 1 to 7, characterised in that respectively three claws (15) and stepped grooves or recesses (9) are provided.

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