GB2446459A

GB2446459A - Hatch having two wings each connected to a common opening and closing pressure supply

Info

Publication number: GB2446459A
Application number: GB0702492A
Authority: GB
Inventors: Rex Michau
Original assignee: TEC ARMECH Ltd
Current assignee: TEC ARMECH Ltd
Priority date: 2007-02-12
Filing date: 2007-02-12
Publication date: 2008-08-13
Anticipated expiration: 2027-02-12
Also published as: GB2446459B; GB0702492D0

Abstract

A hatch 2 comprises two doors 6,7 hinged to opposite sides of an aperture. A first door 6, the first to be opened and the second to be closed, has a lip 8 which overlaps the top of the second door 7. Fluid filled actuated piston and cylinder actuators 12, 13, are provided for opening and closing the doors. Each door has at least one actuator for opening the door and at least one actuator for closing the door, each opening actuator is connected to a common pressure supply and each closing actuator is connector to a common pressure source. The opening actuator of the first door provides a greater opening force or torque than the actuator of the second door and the first door opens first ahead of the second door. The closing actuator of the second door provides a greater closing force or torque than the actuator of the first door and the second door begins to close before the first door. The increased opening and closing forces/torques of the respective actuators may be due to a mechanical advantage or may be due to an increased piston area of the actuator. In one arrangement (fig. 4) actuators 11,12 are connected to the first door 6 and actuators 13,14 are connected to the second door 7. Pneumatic ducts 18,19 for opening and closing pressurised air are provided from connections 20,21 and associated vents 22,23. The ducts are connected to the actuators in the manner shown in Figure 4. Opening pressure supply duct 18 is connected to two actuators 11, 12, on the first door and a single actuator 13 on the second door. Closing pressure supply 19 is connected to a single actuator 12 on the first door and two actuators 13, 14 on the second door.

Description

HATCH

The present invention relates to a hatch, in particular though not exclusively a roof hatch for a transport container.

Roof hatches having two partially overlapping doors require for these doors to be opened sequentially. Systems for this have involved the use of control valves by throttling the valves or complicated piloting valves or mechanically contacting a roller when rams end a stroke. Such systems are liable to be complex, expensive and/or unreliable.

The object of the present invention is to provide a hatch having two partially overlapping doors.

:, According to the invention there is provided a hatch arranged to openably :..::: close an aperture in a structure comprising: first and second hatch doors, the first hatch door overlapping the second hatch door at an overlap extending across the aperture and * * * a system of fluid actuated piston and cylinder actuating devices acting *.. :20 between the structure and the hatch doors for opening and closing the hatch * doors, the system comprising: * . at least one actuating device for opening the first hatch door and at least one actuating device for opening the second hatch door, * these actuating devices having opening pressure sides of the actuating devices connected in common to a opening pressure supply duct, * the opening actuating device(s) for the first hatch door being adapted and arranged to generate a hatch door opening force or torque which is greater than that of the opening actuating device(s) for the second hatch door when both hatch doors are closed and a common opening pressure is applied to the actuating devices, whereby the first hatch door is opened first, * the first hatch door having a limited travel to its open position, in which its actuating device(s) are stopped, whereby the opening pressure can rise to open the second hatch door and * at least one actuating device for closing the first hatch door nd at least one actuating device for closing the second hatch door, * these actuating devices having closing pressure sides of the actuating devices connected in common to a closing pressure supply duct, * the closing actuating device(s) for the second hatch door being adapted and arranged to generate a hatch door closing force or torque which is greater than that of the closing actuating device(s) for the first hatch door when both hatch doors are open and a common closing pressure is applied to the actuating devices, whereby the second hatch door is closed first, * the second hatch door having a limited travel to its closed position, in : . 15 which its actuating device(s) are stopped, whereby the closing pressure can rise to close the first hatch door. * S..

. * It can be envisaged that the arrangement for causing the first hatch door to open first and the second hatch door to be closed first can be achieved by causing the * :*. 20 first hatch door's opening actuating device(s) to act at great mechanical advantage than that or those for the second hatch door, whereby the same force exerted by the S.....

* actuating devices for the two hatch doors at the same opening pressure creates a greater opening torque for the first hatch door, which opens first. Alternatively and preferably, the acted-on-area of the first hatch door's opening actuating device(s), i.e. the effective piston area exposed to the opening pressure, can be greater for the same mechanical advantage than that for the second hatch door, whereby first hatch door is opened first. The same alternatives are available for closing the second hatch door first.

Various configurations for the actuating devices can be envisaged. They can all be single acting actuators, at least four such actuators being provided.

Alternatively they can be double acting actuators, in which case the opening and closing actuating devices for the respective hatch doors can be opposite ends of the ta same actuators, with their piston and rod diameters chosen to provide for the opening acted-on-area for the first hatch door to be greater and the closing acted-on-area for the second hatch door to be greater.

In the preferred embodiment, four identical actuators are provided, with selected ends connected to the two ducts such that two of the actuators have opening pressure applied to cause the first hatch door to open first and the other two actuators have closing pressure applied first to cause the second hatch door to close first.

Normally, as in the preferred embodiment, the hatch doors will be hinged to the structure at opposite sides of the aperture. However again alternatives can be envisaged such as the hatch doors being linked to the structure by parallelogram linkages for translational, as opposed to rotational, opening movement.

:*. 15 To help understanding of the invention, a specific embodiment thereof will S.:: now be described by way of example and with reference to the accompanying *.

drawings, in which: Figure 1 is a perspective view of a transport container having a hatch according to the invention; *:*. 20 Figure 2 is a scrap plan view of the hatch of Figure 1; Figure 3 is a scrap cross-sectional end view on the line Ill-Ill in Figure 2 of S.. .** the hatch; and Figure 4 is a pneumatic diagram for the hatch.

Referring to the drawings, a bulk powder transport container 1 has an filling hatch 2 in its top and a discharge point 3 at its bottom. The hatch is at an aperture 4 having a surrounding frame 5 and a pair of doors 6,7 hinged to opposite sides of the aperture and frame. One of the doors, the first to be opened and the second to be closed has a lip 8, which seals over the top of the adjacent edge of the other door.

Each door has a pair of arms 9 extending downwards and outwards of the hatch aperture. Actuators 11,12,13,14 are connected from the distal ends 15 of the arms 9 to anchor points 16 on the sides of the container. The actuators 11,12 are connected to the first door 6 and the actuators 13,14 are connected to the second door 7.

Typically all the actuators have a 4 inch -100mm internal diameter cylinders and I inch -25mm -diameter piston rods. Thus they have approximately 7850mm2 full acted on area 16 and 7360 mm2 rod-side acted on area 17.

Pneumatic ducts 18,19 for opening and c1ning preuried air are provided in container from connections 20,21 and assoc&ated vents 22,23. The ducts are connected to the actuators in the manner shown in Figure 4.

In particular, the "Open" duct 18 is connected to the full area side 16 of the first door actuators 11,12 and the full area side 16 of one only of the second door actuators 13. The doors are of similar weight and connected similar to the frame 5, their arms and their actuators. Thus application of a unit of pressure to the duct 18 will provide twice the lifting torque from the first door opening actuators 11,12 as from the second door opening actuator 13. As soon as the pressure reaches a level sufficient to raise the first door, it will open and fully so since as it opens the door's weight acts at a reducing lever arm about its hinge 24. The second door has not moved since the opening pressure is still only half of that required to lift it. Once the *...

first door is fully open and stopped, by the actuators reaching the ends of their stroke, * :* . the pressure rises and the second door is opened by its opening actuator 13.

Pneumatic pressure for this operation can be applied via the connection 20. Pressure *. : 20 which might buildup behind the pistons on their rod side 17, is vented via the "Close" * duct 19 and its vent 23. It will be noted that the full area side 16 of the actuator 14 is *se,..

* not acted on by the "Open" duct; rather it is permanently connected to a closed void in the frame 25 of the container. The volume of the void is such that the resultant force acting on the actuator is negligible and has no material effect on the operation of opening and closing of the hatch.

For closure of the hatch, the Open duct is vented to atmosphere via its vent 22 and pneumatic pressure is applied to the Close duct via its connection 21. This pressure acts on the rod side areas 17 of the two actuators 13,14 connected to the second door and on the same side of the one actuator 11 of the first door. Thus in a manner analogous the opening of the first door first, the second door closes first, followed by the first door. The only significant difference is that the second door stops moving not as a result of bottoming its actuators, but closing against the hatch seals 26, whereupon the first door closes as the pressure builds in the actuator 11. -5

As with the frill area side of the actuator 14, the reduced area side of the actuator 11 is connected to the frame void and plays no significant part in the opening and closing sequence.

The Opening and the Closing pressure is convenient applied to the Open and Close ducts by manual connection of a pressure air line to the ducts. The vents 22,23 are conveniently manually operated.

The invention is not intended to be restricted to the details of the above described embodiment. For instance, the vents 22,23 can be operated by pilot valves.

The vents are urged normally closed by springs, but opened by application of pressure from the opposite line to the respective valve, whereby application of pressure to either of the lines automatically vents the other. I... * . *,.. * S * . S * ** S.

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Claims

CLAIMS: I. A hatch arranged to openably close an aperture in a

structure comprising: * first and second hatch doors, the first hatch door when closed overlapping the second hatch door at an overlap extending across the aperture and S * a system of fluid actuated piston and cylinder actuating devices acting between the structure and the hatch doors for opening and closing the hatch doors, the system comprising: * at least one actuating device for opening the first hatch door and at least one actuating device for opening the second hatch door, * these actuating devices having opening pressure sides of the actuating devices connected in common to a opening pressure supply duct, * the or each opening actuating device for the first hatch door being adapted and arranged to generate a hatch door opening force or torque which is greater than that of the or each opening actuating device for the second hatch door when both hatch doors are closed and a common opening pressure is applied to the actuating devices, whereby the first hatch door is opened first, * the first hatch door having a limited travel to its open position, in which its actuating device(s) are stopped, whereby the opening pressure can rise to open the second hatch door and * at least one actuating device for closing the first hatch door and at least one actuating device for closing the second hatch door, **..

* these actuating devices having closing pressure sides of the actuating devices connected in common to a closing pressure supply duct, * the or each closing actuating device for the second hatch door being adapted and arranged to generate a hatch door closing force or torque which is greater than that of the or each closing actuating device for the first hatch door when both hatch doors are open and a common closing pressure is applied to the actuating devices, whereby the second hatch door is closed first, * the second hatch door having a limited travel to its closed position, in which its actuating device(s) are stopped, whereby the closing pressure can rise to close the first hatch door.
2. A hatch as claimed in claim I, wherein the or each actuating device for opening the first hatch door is arranged to act on the first hatch door at a greater mechanical advantage than the or each actuating device for opening the second hatch door is arranged, whereby the same force exerted by the actuating devices for the two hatch doors at the same opening pressure creates a greater torque or force for opening the first hatch door, which opens first.
3. A hatch as claimed in claim 2, wherein the or each actuating device for closing the second hatch door is arranged to act on the second hatch door at a greater mechanical advantage than the or each actuating device for closing the first hatch door, whereby the same force exerted by the actuating devices for the two hatch doors at the same opening pressure creates a greater torque or force for closing the second hatch door, which closes first.
4. A hatch as claimed in claim 1, wherein the or each actuating device for opening the first hatch door has a greater effective piston area arranged to act on the first hatch IS door than the effective piston area of the or each actuating device for opening the second hatch, whereby the force exerted by the actuating devices for the two hatch doors at the same opening pressure creates a greater torque or force for opening the first hatch door, which opens first.
5. A hatch as claimed in claim 4, wherein the or each actuating device for closing the second hatch door has a greater effective piston area arranged to act on the second hatch door than the effective piston area of the or each actuating device for closing the * *.

*... first hatch door, whereby the force exerted by the actuating devices for the two hatch *IdI doors at the same opening pressure creates a greater torque or force for closing the second hatch door, which closes first.
6. A hatch as claimed in any preceding claim, wherein all the actuating devices are : * single acting actuators of which at least four are provided.
7. A hatch as claimed in any one of claims I to 5, wherein all the actuating devices **.

are double acting actuators of which at least two are provided, with the opening and closing actuating devices for the respective hatch doors being opposite ends of the same actuators and with their piston and rod diameters providing for the opening acted-on-area for the first hatch door to be greater and the closing acted-on-area for the second hatch door to be greater.
8. A hatch as claimed in claim 7, wherein: four identical double acting actuators are provided; * two of the actuators are connected to the first door; * the other two of the actuators are connected to the second door; * opening pressure ends of the two first door actuators and one second door actuator are connected to the opening pressure supply duct to cause the first hatch door to open first; and * closing pressure ends of the two second door actuators and one first door actuator are connected to the closing pressure supply duct to cause the second hatch door to close first.
9. A hatch as claimed in any preceding claim, wherein the hatch doors are hinged or i 0 connected by parallelogram linkages to the structure at opposite sides of the aperture.
10. A hatch as claimed in claim 9, wherein springs are provided for biasing the doors closed.
11. A hatch as claimed in claim 9, wherein the doors are arranged to open upwards whereby their weight biases them closed.

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12. A hatch arranged to openably close an aperture in a structure substantially as hereinbefore described with reference to the accompanying drawings. * ** S. S * .5 S... * S *5 3 * S. * S. *Se

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