GB2376056A

GB2376056A - Off-centre valve

Info

Publication number: GB2376056A
Application number: GB0204067A
Authority: GB
Inventors: Alan Frederick Rees
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-02-24
Filing date: 2002-02-21
Publication date: 2002-12-04
Anticipated expiration: 2022-02-21
Also published as: GB0204067D0; GB2376056B

Abstract

A compact plug valve, preferably for a radiator, has a sealing plug which can be rotated about a pivot, wherein the axis of the pivot is offset from the centre line of the valve. The plug may be a part sphere. The angle of rotation may be limited by the pivot. The valve may only use two 'O' rings. In an open position the plug may sit in a area of the valve having a wider cross-section than the rest of the valve. The plug may stop automatically when the valve is fully open or fully closed.

Description

COMPACT FLUID CONTROL VALVE This invention relates to the fitting of a second valve within the limited size of existing central heating radiator valves.

Existing central heating radiators are connected to the pipe-work by a pair of shut off (radiator) valves. If the radiator has to be removed the valves are shut off and the radiator can be detached.

However, there is then nothing to stop the water from flowing out of the radiator. It is desirable to be able to seal the ends of the radiator before the main valves are disconnected. The normal construction of each radiator valve is that the connecting piece between the radiator and the valve is so short that it is very difficult to fit an auxiliary valve into that connecting piece, commonly termed'The Tail'a further problem is that the construction of most accepted form of valves that might fit into a tail restrict water flow to an unacceptable extent.

It is the object of this invention to over come both the problem of length and water flow and provide an auxiliary valve which will fit within the length of the standard tail and not restrict the water flow to

a level which would make the valve fail to comply with the appropriate British Standard.

J The proposed valve consists of three parts and 2'0'ring seals. These parts are (Drawing A) the tubular valve body'1'i. e. the tail, the valve disc'2', the valve stem'3'the main'0'ring seal 4 and the stern'0'ring seal'5'.

The valve is constructed by the main 0 ring'4'sitting in a groove'6'within the disc, which is inserted from the threaded end'7'of the tail, the spindle'3'is inserted through a bore'8'in the valve body into a press fit bore'9'in the disc, it is pressed on into a blind bore hole'10'in the body and is sealed by the smaller ring'5'the spindle can be turned by a screwdriver slot in the head'11'and is free to turn in the main body bores but is a fixed press fit into the disc, thus when the spindle rotates 90 the disc moves with it.

The disc of this valve is formed from the central section of a sphere the front and rear of the disc is flattened or hollowed 12-13 for minimum restriction of water flow. The longitudinal equator of the disc carries a groove, which houses the main'0'ring.

Since the'0'ring is located on the longitudinal equator of the disc it is impossible for the spindle to also be located centrally and rotate the disc in the normal way therefore the spindle is located off centre at 45 to the discs central point, thus when the spindle is turned, the disc moves 90 to a position at right angles to the closed position, with the equator running down the centre of the valve bore, but it does not rotate around its own'Pole'point, the pole point actually moves in an arc around the spindle position.

To provide a firm closed position the valve bore has a step 13 formed into it, the disc stops fully sealed when it comes into contact with this step, because the disc is bored'off centre'and rotates in an arc around an off centre point, the shorter side of the disc is able to rotate to the open position without coming into contact with the bore step (dotted arc marked on drawing'B') in the open position the front and rear flats allow maximum flow over the disc.

The spindle serves the dual purpose of rotating the disc and locating and holding the disc in its correct location the actual valve assembly is positioned to take advantage of the extra thickness provided by the hexagon to achieve maximum bore and minimum flow restriction when open, the disc moves into a wider section of the bore when open, again to maximise water flow.

One potential problem is that when in the open position it is possible for the disc and pin to rise, this is offset as shown in drawing"C". The head of the pin is slightly overlapped by the head of a small rivet fitted alongside the pin head, since the pin only rotates a quarter turn from fully open to fully

closed, the rivet can be positioned on the opposite quarter position so as not to interfere with the movement, but to simply hold down the pin, this rivet has the added advantage of adding to the resistance to the pin movement helping to reduce any chance of the water flow pushing the valve closed, since it has a very free moving design.

Drawing"D"represents a variation, here the body of the vaive (I) is basically the same as drawing "A''but the internal configuration is different, the other main difference is that the valve disc is a quarter sphere and it is drilled and swings on a centrally located pin. The main ring (6) is located in the valve body and the domed area (5) of the quarter ball seats onto this ring when closed, the valve operates in exactly the same way as type (A) i. e. the pin is a rotating fit in the body and a press fit into the ball, to open the valve the pin is rotated a quarter turn.

To accommodate the whole ball or to allow this quarter ball to rotate a quarter turn the valve body has a suitable size bore, and this bore is of such a size that even with the quarter ball inserted into it, the space around the quarter ball when open is sufficient for the valve to pass the amount of water required to comply with the appropriate British standard.

A problem is that there is nothing to stop the core from rotating fully and therefore it may not centre perfectly in either the open or closed position. To offset this problem (drawing"E") the head of the pin is designed to protrude slightly and a small groove is formed around one quarter of it, a small rivet is fitted alongside the pin head so that the rivet head (14) fits into the milled recess thus the pin can only turn a quarter turn and perfectly position the ball in both the open or closed position.

A potential problem with the valve shown in diagram'D'is that in closing it is possible for the'0' ring to move ahead of the dome and pop out of its ring since it is being compressed from one side as the valve closes. Drawing'F'shows a method to offset this potential problem. The pin opens and closes the valve in the same way as the first two examples i. e. press fit into the ball, rotate fit in the valve body, but now the non circular head of the pin fits into a shaped recess and the bottom of the pin which is shaped identically to the top into a shaped recess formed into the inside bottom of the valve body. Both top and bottom of the pin is shaped oval with flattened sides. Drawing'F'No 16 the recess No 17 is formed of 2 circles with their centres (in the example) 2mm apart running down the centre line of the valve, the circle centre nearest the thread end is 2mm further back from the ideal closed position of the quarter dome, whilst the circle centre point of the front circle is perfectly positioned to compress the "0" ring to the desired pressure.

When open the pin oval lies across the valve centre line in the rear circle, as it is rotated to close the shape of the recess pushes the pin and therefore the quarter ball forward 2mm, thus compressing the ring as it rotates into position but not forcing the ring out of its locating groove. To further improve the flow it is possible to now flatten the dome apex since this domed shape is no longer required to slip gently across the'0'ring as the valve closes.

Claims

OFF-CENTRE FLUID VALVE MK 5 CLAIMS 1. A valve which rotates open by moving the valve plug in an arc.
2. A valve, as claimed in one which uses a part sphere as its plug.
3. A valve as in claims I and 2 which uses only 2"0"rings.
4. A valve, in accordance with claims 1, 2 and 3 in which the turn-pin also acts to hold the assembled valve together.
5. A valve as in claims I to 4 which on opening the plug moves and parks in a wider bored area of the valve.
6. A valve as in claims 1 to 5 stops automatically when fully opened or closed.
7. A valve as in claims 1 to 6 in which the turn key and plug is bored"off centre".
8. A valve as in claims 1 to 7 in which the sealing ring is shown machined into the plug, but in which the plug could be machined smooth and the ring fitted into the body.
9. A valve as in claims 1 to 8 where when closed the greater the pressure on the valve the tighter it closes.
10. A valve as in claims 1 to 9 which is so machined as to take advantage of the valves widest exterior area to position its widest internal bored area.
11. A valve as in claims 1 to 10 which will hold a wide range of fluids and gasses by varying the material of the seal rings and materials of which the body is formed.
12. A valve as in claims 1 to 11 in which the plug can move forward or rearward to seal or unseal as it is rotated.