GB2397359A

GB2397359A - Pressure vessel with a safety closure mechanism

Info

Publication number: GB2397359A
Application number: GB0226130A
Authority: GB
Inventors: Charles Albert Prior
Original assignee: PRIORCLAVE Ltd
Current assignee: PRIORCLAVE Ltd
Priority date: 2002-11-08
Filing date: 2002-11-08
Publication date: 2004-07-21
Anticipated expiration: 2022-11-08
Also published as: GB2397359B; GB0226130D0

Abstract

A pressure vessel (2) comprising a body (4), a door and a closure mechanism (8), the closure mechanism (8) comprising a pivoting arm arrangement (14, 16, 18) that moves to an over-centre position (10) for maintaining the door (6) in a closed position, whereby the door (6) will remain closed irrespective of pressure within the body (4).

Description

A PRESSURE VESSEL WITH

A SAFETY CLOSURE MECHANISM

This invention relates to a pressure vessel and, more especially, this invention relates to a pressure vessel with a safety closure mechanism. The pressure vessel may be an autoclave, a steriliser or any other suitable and appropriate type of pressure vessel.

Pressure vessels are well known and they are used for a wide variety of industrial, medical and scientific purposes. The pressure vessels comprise a body and a door, and the door is required to stay closed against various pressures within the body of the pressure vessel. These pressures are often relatively high. Escape of pressurised gas or vapour from within a pressure vessel can be harmful or even fatal to persons in the vicinity of the pressure vessel. In order to keep the door closed, various different types of closure mechanisms are employed. The integrity of the closure mechanisms is of paramount importance and, as such, reliance on just one form of closure mechanism without additional protection has been seen to be undesirable. Hitherto, pressure vessel closure mechanisms have included inflatable door seals, gear boxes or electro-mechanical clutches, all of which can fail for one reason or another.

It is an aim of the present invention to reduce the above mentioned problems.

Accordingly, in one non-limiting embodiment of the present invention, there is provided a pressure vessel comprising a body, a door and a closure mechanism, the closure mechanism comprising a pivoting arm arrangement that moves to an over-centre position for maintaining the door in a closed position, whereby the door will remain closed irrespective of pressure within the body and also in the advent of pressure failure or removal of a driving power source for effecting the closure of the closure mechanism.

The pressure vessel of the present invention is thus able to be used in safety with the knowledge that the door will remain safely sealed with a positive and safe action. In normal circumstances, the door will not be able to be forced open by pressure from within the body of the pressure vessel, and also In the advent of pressure failure or removal of a driving power source for effecting the closure of the closure mechanism, because the pivoting arm arrangement will be in an over-centre position and thus is effectively locked in position.

The pressure vessel may be one in which the closure mechanism comprises drive means, a reciprocating member which is driven by the drive means, a first pivot arrangement, at least one arm, at least one second pivot arrangement, at least one third pivot arrangement, and at least one clamping means for clamping the door in the closed position, the closure mechanism being such that the reciprocating member is connected at a first end to the first pivot arrangement, the arm is connected at a first end to the first pivot arrangement and at a second end to the second pivot arrangement, the clamping means is connected to the second pivot arrangement, the clamping means is pivotally mounted by the third pivot arrangement, movement of the reciprocating member in a first direction causes the first and second pivot arrangements to move in a first direction with the first pivot arrangement being in the over-centre position and the clamping means clamping the door shut, and movement of the reciprocating member in a second direction causes the first and second pivot arrangements to move in a second direction and the clamping means to unclamp the door.

If the pressure vessel has a hinged door arrangement, then only one arm, one second pivot arrangement, one third pivot arrangement and one clamping means may need to be employed. However if the door is to be completely removed from the pressure vessel or the hinge arrangement is not to be relied upon, then the pressure vessel may be one in which there are two of the second pivot arrangements, and in which the over-centre position is achieved when the first pivot arrangement is moved by the reciprocating member to a position beyond an imaginary centre line between the two second pivot arrangements. There will also then usually two of the third pivot arrangements and two of the clamping means, there being one of the third pivot arrangements and one of the clamping means at each of two opposite sides of a front face of the door.

The reciprocating member is preferably a shaft but other types of reciprocating member may be employed if desired.

The drive means is preferably a piston and cylinder drive means.

The piston and cylinder drive means may be a hydraulic, pneumatic, or electric piston and cylinder drive means. Alternatively, the drive means may be an electric motor, for example a linear motor. Any suitable and appropriate drive means may be employed.

The clamping means preferably comprises at least one cam member mounted on a rod which pivots in the third pivot arrangement. Preferably there are three of the cam members mounted on the rod but more or less than three of the cam members may be employed as may be desired. Other types of clamping means may also be employed.

The pressure vessel may include stop means against which the pivoting arm arrangement abuts in the over-centre position. Any suitable and appropriate type of stop means may be employed.

An embodiment of the invention will now be described solely by way of example and with reference to the accompanying drawings in which: Figure 1 is a top plan view of a pressure vessel, the top plan view concentrating on a closure mechanism of the pressure vessel, and the closure mechanism, which in this case is mounted under the vessel, being shown in full lines for ease of illustration; and Figure 2 is a front view of the pressure vessel and the closure mechanism shown in Figure 1.

Referring to the drawings, there is shown a pressure vessel 2 comprising a body 4 and a door 6. The pressure vessel 2 also comprises a closure mechanism 8. As can best be appreciated from Figure 1, the closure mechanism 8 is a pivoting arm arrangement that moves to an over- centre position 10 for maintaining the door 6 in a closed position, whereby s the door 6 will remain closed irrespective of pressure within the body 4 of the pressure vessel 2.

The closure mechanism 8 comprises drive means 12, a reciprocating member 14 which is driven by the drive means 12, and a first pivot arrangement 16. The closure mechanism 8 also comprises two arms 18, two second pivot arrangements 20, two third pivot arrangements 22, and two clamping means 24 for clamping the door 6 in the closed position. The closure mechanism 8 is such that the reciprocating member 14 is connected at a first end 26 to the first pivot arrangement 16. The arms 18 are each connected at a first end 28 to the first pivot arrangement 16, and at a second end 30 to the second pivot arrangement 20. The clamping means 24 is pivotally mounted by the third pivot arrangement 22.

Movement of the reciprocating member 14 in a first direction 32 causes the first and second pivot arrangements 16, 20 to move in a first direction with the first pivot arrangement 16 being in the over-centre position 10, and the clamping means 24 clamping the door 6 shut. Movement of the reciprocating member 14 in a second direction 34 causes the first and second pivot arrangements 16, 20 to move in a second direction, and the clamping means 24 to unclamp the door 6. As can be seen from Figure 1, the over-centre position 10 is achieved when the first pivot arrangement 16 is moved by the reciprocating member 14 to a position beyond an imaginary centre line 36 joining the two second pivot arrangements 20.

As shown in Figure 1, the reciprocating member 14 is a shaft, and the drive means 12 is a piston and cylinder drive means 12 having a piston 38 connected to the reciprocating member 14, and operating in a cylinder 40.

The piston and cylinder drive means 12 may be hydraulically or pneumatically operated via fluid inlets 42, 44 as shown.

The clamping means 24 comprises three cam members 46 each mounted on a rod 48 which pivots in the third pivot arrangement 32. As can best be seen from Figure 2, there are two of the rods 48 positioned one on either side of a front face 50 of the door 6. Each cam member 46 has a rubber or plastics buffer member 52 for ensuring that the front face 50 of the door 6 does not become damaged by the clamping pressure from the cam members 46 which act as clamps.

As can be seen from Figure 1, in the over-centre position 10, the first pivot arrangement 16 is able to abut against a stop means 54. Any suitable and appropriate type of stop may be employed for the stop means 54.

The pressure vessel 2 is able to operate with a considerable degree of safety. During use, hydraulic liquid or compressed air is able to be applied to the inlet 42 of the cylinder 40. The piston 38 within the cylinder moves in the first direction 32 and the first pivot arrangement 16 adopts the over-centre position 10 and the cam members 46 clamp onto the door 6.

No further forward movement of the reciprocating member 14 is possible since the reciprocating member 14 is abutting against the stop means 54.

The clamping means 24 will have operated such that the cam members 46 will have rotated on the rods 48 and the clamping means 24 will then be in full operation clamping against the door 6. The door 6 is thus pressed inwardly to seal against a gasket 56 so that the door 6 is easily, positively ) 7 and safely closed. The door 6 can be opened simply by moving the reciprocating member 14 in the second direction 34, using hydraulic liquid or compressed air in the inlet 44.

It is to be appreciated that the embodiment of the invention described above with reference to the accompanying drawings has been given by way of example only and that modifications may be effected. Thus, for example, the pressure vessel 2 may be an autoclave, a steriliser or any other suitable and appropriate type of pressure vessel. Other types of drive means 12, reciprocating members 14, arms 18, and pivot arrangements 16, 20, 22 may be employed.

Claims

CLAIMS -

1. A pressure vessel comprising a body, a door and a closure mechanism, the closure mechanism comprising a pivoting arm arrangement that moves to an over-centre position for maintaining the door in a closed position, whereby the door will remain closed irrespective of pressure within the body.

2. A pressure vessel according to claim 1 in which the closure mechanism comprises drive means, a reciprocating member which is driven by the drive means, a first pivot arrangement, at least one arm, at least one second pivot arrangement, at least one third pivot arrangement, and at least one clamping means for clamping the door in the closed position, the closure mechanism being such that the reciprocating member is connected at a first end to the first pivot arrangement, the arm is connected at a first end to the first pivot arrangement and at a second end to the second pivot arrangement, the clamping means is connected to the second pivot arrangement, the clamping means is pivotally mounted by the third pivot arrangement, movement of the reciprocating member in a first direction causes the first and second pivot arrangements to move in a first direction with the first pivot arrangement being in the over- centre position and the clamping means clamping the door shut, and movement of the reciprocating member in a second direction causes the first and second pivot arrangements to move in a second direction and the clamping means to unclamp the door.

3. A pressure vessel according to claim 2 in which there are two of the second pivot arrangements, and in which the over-centre position is achieved when the first pivot arrangement is moved by the reciprocating member to a position beyond an imaginary centre line between the two second pivot arrangements.

4. A pressure vessel according to claim 3 in which there are two of the third pivot arrangements and two of the clamping means, there being one of the third pivot arrangements and one of the clamping means at each of two opposite sides of a front face of the door.

5. A pressure vessel according to any one of claims 2 - 4 in which the reciprocating member is a shaft.

6. A pressure vessel according to any one of claims 2 - 5 in which the drive means is a piston and cylinder drive means.

7. A pressure vessel according to claim 6 in which the piston and cylinder drive means is a hydraulic, pneumatic or electric piston and cylinder drive means.

8. A pressure vessel according to any one of claims 2 - 5 in which the drive means is an electric motor.

9. A pressure vessel according any one of the preceding claims in which I the clamping means comprises at least one cam member mounted on a rod which pivots in the third pivot arrangement.

10. A pressure vessel according to claim 10 in which there are three of the cam members mounted on the rod.

11. A pressure vessel according to any one of the preceding claims and including stop means against which the pivoting arrangement abuts in the over-centre position.

12. A pressure vessel substantially as herein described with reference to the accompanying drawings.