Lockable Closure Cap

The application relates to a lockable closure cap to be actuated, especially by a key, whereby via an eccentric collar rotated by the locking cylinder a lock catch can be actuated and moved into its locked or unlocked position in a direction normal to the cylinder axis.

Of such closure caps it is generally demanded that lock parts inserted therein and actuated from the outside be mounted sealed in such a manner that the contents of the closed container or a pipe socket is unable to spill out via the mounted lock part. Also, it should be ensured that the sealing of the lock parts in the cap are so formed that their sealings effect may be maintained.

It is known to use sealing rings located within the closure cap pressing against the lock cylinder, for both screw-type closure caps and bayonet catch caps. It is also known to provide sealing collars acting against a central socket below the outer cover cap which, however, cannot prevent liquid from spilling out along the lock cylinders mounted in the interior of such hollow sockets. Finally, it is also customary to seal closing cylinders inserted in caps at the end, say such as by means of sealing rings, or by sealing caps enclosing the locking cylinders completely at the base.

It is an object of the invention to provide a cylinder lock mounted centrally in a closure cap so as to be sealingly enclosed.

According to the present invention there is provided a closure cap secured by a cylinder lock wherein the lower end of the lock cylinder is connected to the base of a cup-shaped hollow cylindrical part partially enclosing the lock cylinder, the outer walls of the hollow cylindrical part having an eccentric collar on which there is supported a locking ring having a catch projection which can be displaced radially, dependent upon the movement of a key in the lock, into a locked or unlocked position, and the upper edge of the hollow cylindrical part abuts a sealing ring under the action of a compression spring supported in the cap housing.

The present invention will be described further, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 shows a closure cap in cross-section along the line I--I of FIG. 2; and

FIG. 2 is a sectional view along the line II--II of FIG. 1.

In the Figures, an outer cap part 1 is shown as having projections 1' spaced around the circumference and acting as hand-grips (as additionally indicated in FIG. 2 in plan view). An inner, spring housing part 2 is located within the outer cap part 1 to form a cap unit therewith. A cylinder lock 3 with lateral tumblers 3' is inserted within a hollow cylindrical central socket 4 mounted in the cap unit and the lower end of the lock cylinder 3 engages a base 5 of a cup-shaped hollow cylindrical element 5' and may be positively coupled therewith by means of cam extensions 3" received in corresponding recesses in the base 5. This cup-shaped cylinder 5' extends upwardly and around the central socket 4 and is so mounted as to be rotatably displaceable within the cap unit. The cylinder 5' has an eccentric collar 5" supporting a ring 6 having an angled locking catch 6' projecting from one side. Upon movement of a key in the lock, the cylinder 3 rotates and the lower cam extensions 3" thereof rotate the cup-shaped cylinder 5' via their base engagement. The locking catch ring 6 located on the eccentric collar 5" is actuated by the rotation of the cylinder 5' to slide the locking catch 6' radially outwards through an aperture 2" into its locking position. The aperture 2" is bent inwardly of the part 2 in order to provide the catch 6', upon an opposite movement of the key in the lock and corresponding withdrawal of the catch 6' into its open position, with an abutment on the cap wall at 2". A sealing ring 8 is supported on an upper edge 5"' of cylinder 5', which sealing ring 8 is compressed by a spring 7 supported between the collar 5" and a base 2"' of the housing. Below the collar 5", a flat ring 9 is provided, whereby a better abutment bearing between the compression spring 7 and the flange wall 5" is ensured, and then catch ring 6 is securely supported on collar 5". The sealing ring 8, biased by the spring 7, presses from below against an inclined inner edge 10' of an intermediate annular plate 10 and laterally against the socket 4 with constant pressure. Between the intermediate plate 10 and a radially outwardly extending section 2' of the lower cap housing, a flat sealing ring 11 is inserted. A conventional sealing ring 12 is provided on the underside of section 2' for abutment against the container or socket nut, not shown.

A plate-shaped member 13 having a large central hole 13" is formed as a bayonet catch bridge having two bayonet catches 13' angled upwards (only one of which is shown), which extend through apertures 2.sup.IV diametrically opposite one another in the housing wall 2. Upon tightening the cap 1, the catches 13 engage with the neck of a container or socket, not shown, and a further compression spring 14 supported between the bayonet bridge plate 13 and the cap base 2"' resiliently biases the plate 13.

The compression springs 7 and 14, supporting the cylinder 5' and the bayonet bridge plate 13, respectively, are mutually coaxially supported with a small spacing between them in an annular depression 2.sup.V pressed out of the base 2"' of the cap.

The cylinder 5' with eccentric collar 5" for controlling the locking catches 6' of the ring 6 can be made of synthetic plastic material.

A modified embodiment for the closure cap with automatic pressure compensation can be obtained by providing at least one shallow radial groove 10 in the edge 10' of the plate 10, such that a passage is provided between the sealing ring 8 and the edge 10' through which only gases or vapours can pass, thus providing corresponding pressure compensation whilst preventing liquid from escaping. In this case the outer edges of the intermediate plate 10 and an edge of the section 2' may be provided with grooves 10"' and 2.sup.V ; for providing external communication around the cap edge 1".