NO346648B1

NO346648B1 - A closure for an opening.

Info

Publication number: NO346648B1
Application number: NO20200888A
Authority: NO
Inventors: Runar Tenfjord
Original assignee: Tenko As
Priority date: 2020-08-07
Filing date: 2020-08-07
Publication date: 2022-11-14
Also published as: NO20200888A1

Description

A closure for an opening

Technical field

The present disclosure relates to a closure for an opening.

Background art

Closures such as hatches, covers, flaps, doors and the like are used across many industries and come in different sizes and with differing operating mechanisms. Due to the wide-ranging use of closures, the differences between any two closures may be vast, and can vary greatly in complexity.

Closures that are already known may be unsatisfactory in many respects. Common reasons include the closures having an excess of parts, being complicated to operate, cumbersome requiring specialist tools to remove and replace, obstructing adjacent workspace or storage space, lacking in operational safety, lacking in good and durable seals, or having operational parts that are prone to rust or corrosion.

In some industries, for example the offshore industries, there may be stringent safety requirements for closures. For example, closures may be required to provide an airtight seal, may be required to withstand a certain level of pressure differential thereacross, or may be required to have safety features should sealing or closing aspects fail.

Publications which may be useful to understand the field of technology include US2179495; US20050199355; US3084827; US20110148631. In US3295878 a fastening apparatus for use in conjunction with doors is disclosed.

There is a need for a closure that is easy to operate, without an abundance of parts that may be prone to corrosion or breakage, and that are not going to obstruct the operations of a user. In addition, there is a need to have a closure that is safe to operate, and that adheres to safety requirements appropriate to its place of use.

Summary

It is an object of the present disclosure to mitigate, alleviate or eliminate one or more of the above-identified deficiencies and disadvantages in the prior art and solve at least the above-mentioned problem.

According to a first aspect, there is provided a closure for an opening, comprising:

a cover;

a locking mechanism, at least a part thereof being coupled to the cover, configurable between a locked configuration in which the closure is secured over the opening and restricts passage therethrough, and an unlocked configuration, in which the closure may be removed from the opening and provides no restriction to passage through the opening,

the locking mechanism comprising a locking member configured to engage a structure around the opening in the locked configuration, a biasing member arranged to urge the locking member towards the locked configuration, and a hydraulically actuated opening mechanism operable to move the locking member towards the unlocked configuration;

a hydraulic chamber, at least part thereof being coupled to the cover, and being configurable to hold a volume of hydraulic fluid, the hydraulic chamber being in fluid communication with the opening mechanism; and

an actuator configurable to increase the pressure in the hydraulic chamber to provide a flow of hydraulic fluid from the hydraulic chamber and to the opening mechanism.

In use, the closure may provide the user a way to restrict, or even prevent, passage through an opening such as a porthole, a hatch, a manhole, or the like. In this case, the closure comprises few moving parts. It may be actuated in a fail safe in closed position by the biasing member, leading to a simple design which may be less prone to failure than other designs.

In examples where the hydraulically actuated opening mechanism, the hydraulic chamber, and the actuator are all located on the cover of the closure, the entire closure may be provided in a compact and simple form. This may permit an easier installation than prior designs, and the disclosed closure may permit the entire closure to be simply removed by the user, and replaced if necessary. In addition, having all parts contained in a single component may facilitate ease and speed of installation, as multiple parts are not required to be installed separately.

The actuator comprises, or is in the form of, a piston and is positioned within the hydraulic chamber, and axial movement of the actuator relative to the hydraulic chamber varies. The actuator may have a cylindrical shape, and may contain a cylindrical cavity therein to house the piston. Having a piston may permit a user to simply and easily vary the pressure of hydraulic fluid in the hydraulic chamber.

The actuator is threadedly connected to the hydraulic chamber, or is threadedly connected to the piston in the hydraulic chamber, and the pressure of the hydraulic fluid in the chamber may be varied by rotation of the actuator. Either the piston, or they hydraulic chamber, or both, may comprise a threaded surface such that turning the actuator enables linear movement of the piston and thereby variation in pressure of the hydraulic fluid. In some examples, the piston and the actuator may be integrally formed, while in other examples, the piston and the actuator may be separate components. Actuation by turning the actuator may provide a simple way of a user applying a large increase in pressure of hydraulic fluid with minimal effort and thereby counteract the biasing member for unlocking.

The biasing member may be a helical spring, a leaf spring, an elasticated member, or any other appropriate component providing the desired biasing force. Having the biasing member will permit the locking mechanism to have a fail-safe function, thereby secure the safety of user of the closure. In the event of a leakage or removal of hydraulic fluid pressure, the biasing member may ensure a locking action is still in place.

The locking mechanism may comprise a locking member that, when the locking mechanism is in the locked configuration, extends outwardly from the centre of the closure. According to some examples, the locking mechanism may be positioned on the cover such that, in the locked configuration, the locking member protrudes outwardly of the periphery of the cover. As such, the enclosure may be usable to engage with brackets or engagement profiles positioned adjacent the opening, for example adjacent the periphery of the opening.

The locking mechanism may be able to completely disengage from a bracket and/or engagement profile on a surface adjacent the opening, which may permit the closure to be very easily removed from the opening, and if desired replaced.

The hydraulic chamber may be connected to the locking mechanism via a fluid conduit. As such, the fluid conduit may permit a dedicated fluid channel through which hydraulic fluid may flow.

The closure may comprise a plurality of locking mechanisms, for example the closure may comprise four locking mechanisms. Having multiple locking mechanisms may reduce the any forces acting on the locking mechanisms when in the locked configuration and, for example, a high-pressure differential is acting across the closure.

The cover may be circular in shape. Such a circular shape may be suitable for using the closure to close a porthole.

The cover may comprise a peripheral (e.g. a circumferential) seal, that may be designed to seal against the periphery (e.g. the circumference) about the opening, thereby enabling the cover to effectively restrict fluid flow through the opening.

The closure may comprise a plurality of locking mechanisms evenly radially spaced on the cover. The even spacing may assist to prevent fluid flow through an opening when the closure is in place. Having an even spacing of locking mechanisms may more reliably or more stably hold the locking mechanism in place over an opening.

The locking mechanism may be coupled to the cover via a secondary member, such as a protective cover. The protective cover may be designed to protect the cover against corrosion, or damage of another kind. The cover may be a plastic cover, for example, or a water repellant coating.

The actuator may be remotely operable. The actuator may comprise a receiver and computer-processing unit such that it is able to receive signals from a user indicating that the opening mechanism should be actuated or otherwise. In such examples, the user may not require a physical key to operate the closure.

The actuator may comprise a surface profile for insertion of a key therein. The surface profile may be prismic in form (e.g. a triangular, cubic prism, or the like) and may permit the user to apply a large amount of torque to the actuator so that the actuator is able to be rotated as required.

The closure may prevent passage through the opening. For example, passage of a fluid or passage of tooling, equipment, etc.

The opening may be a porthole. As such, the opening may be particularly useful in industries where portholes are a common occurrence, such as in the offshore industry.

The actuator may be accessible from a first side of the cover and the locking mechanism may be arranged on a second, opposite, side of the cover. As such, the locking mechanism may be arranged on the inside of an opening while the closure can be operated from the outside.

The hydraulic chamber, a part of the actuator, and/or the fluid conduit may, additionally or alternatively, be arranged on the second side.

The locking mechanism may be fixed to the cover via attachments which are accessible from a first side of the cover while the locking mechanism is arranged on a second, opposite, side of the cover. This may, for example, allow the locking mechanism to be dismantled in the event of a failure of the locking mechanism.

According to a second, not claimed aspect, there is provided a method for closing an opening with a closure, comprising:

providing a closure according to the first aspect, for example having a cover and a hydraulically actuated locking mechanism and a hydraulic chamber coupled thereto;

locating the closure over an opening so as to restrict passage through the opening;

activating the locking mechanism to secure the closure in place over the opening.

Effects and features of the second aspect are to a large extent analogous to those described above in connection with the first aspect. Embodiments mentioned in relation to the first aspect are largely compatible with the second aspect.

The present disclosure will become apparent from the detailed description given below. The detailed description and specific examples disclose preferred embodiments of the disclosure by way of illustration only. Those skilled in the art understand from guidance in the detailed description that changes and modifications may be made within the scope of the disclosure.

Hence, it is to be understood that the herein disclosed disclosure is not limited to the particular component parts of the device described since such device may vary. It is also to be understood that the terminology used herein is for purpose of describing particular embodiments only, and is not intended to be limiting. It should be noted that, as used in the specification and the appended claim, the articles "a", "an", "the", and "said" are intended to mean that there are one or more of the elements unless the context explicitly dictates otherwise. Thus, for example, reference to "a unit" or "the unit" may include several devices, and the like. Furthermore, the words "comprising", "including", "containing" and similar wordings does not exclude other elements or steps.

As will further be understood, references to “upper”, “lower” or similar terms relate only to the orientation as illustrated in the figures, to aid understanding when reading the present disclosure. In use, any closure discussed herein may be arranged in any suitable orientation, such as horizontally, vertically, or at an angle to the horizontal or vertical.

Brief descriptions of the drawings

The above objects, as well as additional objects, features and advantages of the present disclosure, will be more fully appreciated by reference to the following illustrative and non-limiting detailed description of example embodiments of the present disclosure, when taken in conjunction with the accompanying drawings.

Figures 1a and 1b are perspective views of an example of a closure.

Figure 2 is a plan view of the top of an example of a closure.

Figure 3 is an elevation view of an example of a closure.

Figure 4 is a sectional view of an example of a closure.

Figure 5 is a sectional view of Section A-A as shown in Figure 2.

Figure 6 is a close-up view of detail B as illustrated in Figure 5.

Detailed description

The present disclosure will now be described with reference to the accompanying drawings, in which preferred example embodiments of the disclosure are shown. The disclosure may, however, be embodied in other forms and should not be construed as limited to the herein disclosed embodiments. The disclosed embodiments are provided to fully convey the scope of the disclosure to the skilled person.

The embodiments described here may be suitable, for example, for onshore industry or to marine architecture including ships, barges, and other vessels having hatches or manholes of various sizes and shapes, necessary for access to or egress from a compartment or area on the remote side of a deck, floor, wall or the like, and, optionally, with sealing means to prevent the leakage of water or other liquid therethrough.

Figure 1a illustrates an example of a closure 10 having a cover 12 that is planar and circular in shape, although the cover 12 may in other embodiments have a different shape, such as rectangular. The closure 10 may, for example, be a closure for a hatch or manhole. In this example, the cover 12 comprises four locking mechanisms 14, although the skilled reader will appreciate that a closure 10 having more or fewer locking mechanisms 14 would be possible, in light of the following description. Located centrally on a flat surface of the circular closure 10 is a hydraulic fluid chamber 16. The hydraulic fluid chamber is able to hold a volume of hydraulic fluid, and in this case is fluidly connected to each of the four locking mechanism 14 via hydraulic conduit 18. As is visible in Figure 1a, the hydraulic chamber 16 is connected to each of the four locking mechanisms 14 in a series arrangement, although the skilled reader will appreciate that other arrangements may be possible, for example the hydraulic chamber 16 may comprise a direct connection to each of the locking mechanisms 14.

Each of the four locking mechanisms 14 comprises a locking member 20, which may be selectively extended and withdrawn in order to selectively lock and release the closure 10, as will be described. In this example, each of the four locking mechanisms is positioned such that the locking member 20 is proximate the outer circumference 22 (e.g. the rim) of the cover 12. In Figure 1a, the locking member 20 is illustrated in the extended configuration (e.g. the locked configuration). In this configuration, when viewed at an angle perpendicular to the flat surface of the cover 12, a portion of the locking member 20 extends radially past the outer circumference 22 of the cover 12. This portion of the locking member 20 may engage an external surface and may, for example, secure the closure 10 over an opening (not shown). When the locking member 20 is in the withdrawn or retracted configuration, the locking member 20 will not extend past the outer circumference 22. In the example provided, each of the locking mechanisms 14 may completely disengage from an external structure, and permit the complete removal of the closure 10, for example if the closure 10 needs to be replaced or simply removed.

In this example, each of the four locking mechanisms 14 are evenly circumferentially distributed around the cover 12, such that each is offset by 90 degrees compared to those circumferentially adjacent. The skilled person will realise that, were more or fewer locking mechanisms 14 to be used, then even circumferential placement would be possible by offsetting each locking mechanism 14 by a different angle. Similarly, the skilled reader will understand that even circumferential placement of the locking mechanisms 14 is not essential, and an uneven arrangement may equally be possible.

As can be seen in Figure 1a, each of the locking mechanisms 14 are substantially identical, and comprise an outer housing 24 that houses internal moving parts. Each of the housings 24 comprise a first hydraulic fluid port 26a for introducing hydraulic fluid into the housing 24 to increase the fluid pressure therein. In this example, three of the locking mechanisms 14 comprise a second hydraulic fluid port 26b, which may connect the housing 24 of the locking mechanism to a first hydraulic port 26a of an adjacent locking mechanism 14, thereby enabling flow of a hydraulic fluid between each of the locking mechanisms 14 in a series arrangement.

Figure 1b is a perspective view from above the closure 10, and shows a cover 12 and two of the four locking mechanisms 14 located on a lower surface of the cover 12. In this example the locking mechanisms 14 are attached to the cover 12 via bolts 28, which can be seen on the upper surface 12a of the cover 12. Additionally illustrated is part of an actuator 30 which is usable to vary the pressure in the hydraulic chamber (see Figure 1a). In this example, the actuator 30 comprises a surface profile, for insertion of a key therein. In this example, the surface profile is in the shape of a cubic or cuboid-shaped depression. In use, a key may be inserted into the surface profile of the actuator 30 and turned to vary the pressure in the hydraulic chamber, as will be described in more detail in the following paragraphs. Varying the pressure in the hydraulic chamber may be used to force hydraulic fluid from the hydraulic chamber and into the housings of the locking mechanisms 14, thereby configuring the locking mechanisms between the locked and unlocked configurations. Although the actuator 30 is illustrated on an upper surface 12a of the cover 12, the skilled reader will appreciate that it may be located on a lower surface 12b thereof. Similarly, it may be possible to position the hydraulic chamber 16 on an upper surface 12a, as opposed to the lower surface 12b as illustrated in Figure 1a.

Further, while the actuator 30 is illustrated as being located on the cover 12 in Figure 1b, it may additionally be possible to have an externally located actuator that is connected to a hydraulic power unit, that is then able to provide pressurised hydraulic fluid to the locking mechanisms 14.

In Figure 2 is illustrated a plan view of the closure 10 shown in Figs 1a and 1b. Figure 3 is an elevation view of the closure 10, with the locking mechanism 14 in the locked configuration, and as such the locking members 20 in the extended position. As is also evident from Figure 3, the cover is planar in shape having a significantly larger width and length as compared to thickness.

Figure 4 illustrates an example of a closure 10, which may be locked in place over an opening 32, and which is illustrated in a cross-sectional view. In this example, the closure 10 is positioned such that, when located over the opening 32, the upper surface of the cover 12 lies flush with a surface 32a adjacent the opening. In addition, set back from the opening is a ridge 33 which is able to be engaged by the locking mechanism 14 of the closure 10, enabling the closure 10 to be locked in place. The ridge 33 may, for example, be a protrusion or bar arranged in or adjacent the opening 32. Optionally, the locking mechanism 14 may engage a different part of the structure 39 around the opening 32.

In any of the embodiments described herein, the ridge 33 may be arranged to receive the cover 12 and support the cover 12 thereon in the closed position. The cover 12 may, for example, rest on an upper surface of the ridge 33. The ridge 33 may extend continuously about the opening 32 (e.g. circumferentially in the case of a circular opening 32), or the ridge 33 may be made up of spaced sections, for example four sections spaced 90 degrees about the opening 32. A continuously arranged ridge 33 may be an advantage for enhanced support of the cover 12 when installed, and/or if using a seal 35 as described below.

In this example, between the closure 10 and the ridge 33 is located a seal 35.

Optionally, a seal 35 may be arranged between the closure 10 and a different part of the structure around the opening 32. Therefore, in this example, the closure 10 may be able to completely prevent passage of fluid through the opening 32.

The structure 39 around the opening 32 comprises an engagement surface 37 configured for engagement with the locking member(s) 20. In the examples shown here, the engagement surface is arranged on the underside of the ridge 33. (See Fig.4.) Providing the engagement surface 37 at an opposite side of the support surface on which the cover 12 lands (in this case, the upper side of the ridge 33) allows for enhanced locking capability.

Optionally, the engagement between the locking member(s) 20 and the engagement surface 37 can be arranged at an angle. For example, the ridge 33 may have a bevel of five degrees, which may act as a force multiplier of e.g. ten times the axial spring force of the closure 10 to provide a downward force on the cover 12 against the support surface. Such a compressive force may, for example, be advantageous if using a seal 35, thereby enhancing the sealing capabilities.

The skilled reader will recognize, however, that in some examples the cover 12 may not sit flush with the opening 32 (e.g. it may be located forward or backwards of the opening 32), and in some cases the closure may secure itself directly to the structure 39 around the opening 32, and the opening may not comprise a protrusion or ridge onto which the closure is fastened.

As in previous examples, the locking mechanism 14 comprises a locking member 20, which may be extended or retracted from the locking mechanism 14 to configure the locking mechanism between a locked and an unlocked configuration. In Figure 4, the locking member 20 is illustrated in a retracted configuration (and therefore the locking mechanism is illustrated in the unlocked configuration), with the position of the locking member 20 being illustrated in faded/broken outline in the extended configuration (and the locking mechanism being in the locked configuration).

Advantageously, in any of the embodiments described herein, the locking member(s) 20 may be movable in a direction which is parallel to the planar cover 12. (I.e. horizontally as shown in Figures 3-6, where the cover 12 is arranged horizontally.)

In Figure 4 it is visible that the housing 24 of the locking mechanism 20 comprises a cavity 34 therein which partially houses the locking member 20, and also houses a biasing member 36, which in this example is in the form of a helical spring, although the skilled reader will appreciate that other forms of biasing member may be equally appropriate. Here, the biasing member 36 acts to urge the locking member 20 towards the extended configuration, thereby configuring the locking mechanism 14 to the locked configuration. As such, the locking mechanism 14 can be considered to be a fail-close mechanism, as in the event of loss or removal of hydraulic pressure, the biasing member 36 will urge the locking mechanism 14 to the locked configuration.

Here, the hydraulic chamber 16 is also illustrated in cross section. As previously described, the hydraulic chamber 16 may comprise an actuator 30 which has a profile for engagement of a key. Inside the hydraulic chamber 16 is a piston 38 which may be used to increase or decrease the pressure of a hydraulic fluid in the hydraulic chamber 16. The piston is sealed relative to the walls of the hydraulic chamber (and comprises a sealing arrangement therefor). Here, the hydraulic chamber 16 comprises a threaded member 40 located therein, while the piston 38 comprises a threaded aperture in which the threaded member 40 is positioned. The user may be able to turn the threaded member by inserting a key into the actuator 30 and turning the actuator, thereby raising or lowering (depending on the direction in which the key is turned) the piston 38 and increasing or decreasing the pressure of the hydraulic fluid contained in the hydraulic chamber 16.

In the example of Figure 4, the actuator 30 is axially displaced from the threaded member 40. Axial movement of the actuator 30 may be possible to engage the actuator 30 with the threaded member 40, thereby enabling turning of the threaded member 40 only when an axially directed force is applied to the actuator 30. This feature may improve the safety of the closure 10 by preventing or reducing the likelihood of unintentional reduction or increase in hydraulic fluid pressure.

Figures 5 illustrates a further cross sectional view of the closure 10, while Figure 6 illustrates detail B as indicated in Figure 5. In the example of Figure 5, the actuator 30 and the threaded member 40 are combined into a single member. As such, no axially directed force may be necessarily applied to the actuator 30 in order to turn the threaded member 40 and vary the pressure of hydraulic fluid in the hydraulic chamber 16. Also illustrated here is a fluid port 42 in the hydraulic chamber 16 which may be used to deliver hydraulic fluid to/from the hydraulic conduit 18.

In Figure 6, detail B of Figure 5 is illustrated. Here, the locking member 20 is illustrated in an extended configuration, and therefore the locking mechanism may be considered to be in a locked configuration. Here, part of the locking member 20 is located in the housing 24. The housing is in this case made from two parts that may be connected together in any appropriate way (e.g. by screwing, chemical bonding, welding, or the like). A radially inner part of the housing 24a houses part of the biasing member 36, while a radially outer part of the housing 24b houses the remaining part of the biasing member 36, as well as part of the locking member 20.

Here, the locking member 20 is able to move axially within the housing 24, similar to a piston in a cylinder. The locking member 20 comprises a part thereof in the shape of a piston 46 (e.g. having an increased diameter in relation to the rest of the locking member 20), with a circumferential seal 44 positioned between the housing and the increased diameter portion 46. The piston portion then creates an annulus 47 that is located between the locking member 20 and the housing, and is located radially outwardly of the piston 46. A seal 48 can also be located on the locking member 20 between the housing and the locking member to prevent leakage of hydraulic fluid therebetween.

As shown in Figure 6, the biasing member 36 provides a force on the locking member 20 to urge the locking member into the extended configuration, thereby configuring the locking mechanism 14 to the closed configuration. Although not shown in detail, the hydraulic chamber 16 is connected to the annulus 47 such as to allow hydraulic fluid to be provided to the annulus 47 via the conduit 18. Thus, if the annulus is filled with hydraulic fluid, the locking member 20 is withdrawn into the housing, and the locking mechanism 14 moves to the open configuration. As such, an increase in the pressure of the hydraulic fluid in the hydraulic chamber has the effect of configuring the locking mechanism to the unlocked configuration, overcoming the force of the biasing member 36.

Advantageously, in any of the embodiments described herein, the actuator 30 may be accessible from a first side, in this case the upper side, while the locking member(s) 20 are arranged on a second side (here: the underside) of the cover 12. The hydraulic fluid chamber 16, a part of the actuator 30, and/or the conduit(s) 18 may be arranged on the second side.

As can be seen in Figure 4, the locking mechanisms 14 may be attached to the cover 12 via attachments, in this example bolts 28. If a failure in the locking mechanism occurs, the closure 10 may be opened by unscrewing the bolts 28 and removing the cover 12.

Advantageously, the attachments (here: bolts 28) are accessible from the first side (here: the upper side) in order that the locking mechanism(s) 14, if necessary, can be released from the cover 12 from the upper side. The attachments can be any suitable attachment means.

The person skilled in the art will realise that the present disclosure is not limited to the preferred embodiments described above. The person skilled in the art further realizes that modifications and variations are possible within the scope of the appended claims.

Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed disclosure, from a study of the drawings, the disclosure, and the appended claims.

Claims

1. A closure (10) for an opening (32), the closure (10) comprising:

a cover (12);

a locking mechanism (14), at least a part thereof being coupled to the cover (12), configurable between a locked configuration in which the closure (10) is secured over the opening (32) and restricts passage therethrough, and an unlocked configuration, in which the closure may be removed from the opening (32) and provides no restriction to passage through the opening (32),

the locking mechanism (14) comprising a locking member (20) configured to engage a structure (39) around the opening (32) in the locked configuration, a biasing member (36) arranged to urge the locking member (20) towards the locked configuration, and a hydraulically actuated opening mechanism (44,47) operable to move the locking member (20) towards the unlocked configuration;

a hydraulic chamber (16), at least part thereof being coupled to the cover (12), and being configurable to hold a volume of hydraulic fluid, the hydraulic chamber (16) being in fluid communication with the opening mechanism (44,47); and

an actuator (30) configurable to increase the pressure in the hydraulic chamber (16) to provide a flow of hydraulic fluid from the hydraulic chamber (16) and to the opening mechanism (44,47).

wherein the actuator (30) is in the form of a piston (38) and is positioned within the hydraulic chamber (16), and axial movement of the actuator (30) relative to the hydraulic chamber (16) varies,

characterized in that the actuator (30) is threadedly connected to the hydraulic chamber (16), and the pressure of the hydraulic fluid in the chamber (16) may be varied by rotation of the actuator (30).

2. The closure (10) of claim 1, wherein the locking member (20), when the locking mechanism (14) is in the locked configuration, extends outwardly from the centre of the closure (10).

3. The closure (10) of claim 2, wherein the locking mechanism (14) is positioned on the cover such that, in the locked configuration, the locking member (20) protrudes outwardly of the periphery of the cover (12).

4. The closure (10) of any preceding claim, wherein the hydraulic chamber (16) is connected to the locking mechanism (14) via a fluid conduit (18).

5. The closure (10) of any preceding claim, comprising a plurality of locking mechanisms (14).

6. The closure (10) of any preceding claim, wherein the actuator (30) comprises a surface profile for insertion of a key therein.

7. The closure (10) of any preceding claim, wherein the actuator (30) is accessible from a first side of the cover (12) and the locking mechanism (14) is arranged on a second, opposite, side of the cover (12).

8. The closure (10) of claim 7, wherein the hydraulic chamber (16), a part of the actuator (30), and/or the fluid conduit (18) are arranged on the second side.

9. The closure (10) of any preceding claim, wherein the locking mechanism (14) is fixed to the cover (12) via attachments (28), and wherein the attachments (28) are accessible from a first side of the cover (12) and the locking mechanism (14) is arranged on a second, opposite, side of the cover (12).