GB2404237A

GB2404237A - Butterfly valve

Info

Publication number: GB2404237A
Application number: GB0317045A
Authority: GB
Inventors: Paul Adrian Wareham
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-07-22
Filing date: 2003-07-22
Publication date: 2005-01-26
Also published as: GB0317045D0

Abstract

A butterfly valve (10) comprises a valve body (12) having a passageway (22) therethrough, a spindle (14) mounted for rotation in the valve body 12 about the axis of the spindle and extending across the passageway, and a butterfly valve member (16 figure 5) mounted in the passageway on the spindle for rotation with the spindle. A detent arrangement (20) releasably holds the spindle 14 in its position extending across the passageway 22, and the spindle is mounted for sliding movement in the valve body so that, upon release of the detent arrangement 20, the spindle 14 can be withdrawn from the valve body by movement in the direction of the spindle axis. The valve member has a vane portion (40) that is offset from the spindle axis, and the vane portion has a peripheral sealing surface (50) that is part-spherical about a sphere axis that is generally coincident with the spindle axis. The valve body has an annular groove (28) offset from the axis of the spindle 14, and a resilient annular seal element (18) is seated in the annular groove for sealing with the peripheral sealing surface of the vane portion when the spindle is in its closed position. The body is formed with a hole (30) extending to the root of the groove 30 into which an element can be inserted to dislodge the seal element from the groove.

Description

TITLE

Butterfly Valves

DESCRIPTION

This invention relates to butterfly valves.

More particularly, a first aspect of this invention relates to a butterfly valve of the type comprising a valve body having a passageway therethrough, a spindle mounted for rotation in the valve body about the axis of the spindle and extending across the passageway, and a butterfly valve member mounted in the passageway on the spindle for rotation with the spindle so that, in a closed position of the spindle, the valve member extends in a direction across the passageway and, in an open position of the spindle, the valve member extends in a direction along the passageway.

Various designs of such butterfly valves are known and are used in various applications, including controlling the flow of fluid or particulate food products. In this case, there is a need for the valve to be kept clean. This can be done by cleaning the valve regularly. In one design of butterfly valve, the valve member is secured to the spindle by releasable fasteners such as screws. Once the valve member has been removed from the spindle, the spindle can be removed from the valve body and the various parts can be cleaned. In another design, the valve body can be split so that the valve member and spindle can be removed, and the various parts can then be cleaned. Alternatively, cleanliness can be maintained by using disposable valves that are replaced regularly, but this is wasteful.

The first aspect of the invention is concerned with providing a butterfly valve that can be more easily disassembled for cleaning.

In the butterfly valve of the first aspect of the invention, a detent arrangement is provided for releasably holding the spindle in its position extending across the passageway, the spindle is mounted for sliding movement in the valve body so that, upon release of the detent arrangement, the spindle can be withdrawn from the valve body by movement in the direction of the spindle axis, and the valve member and spindle are mounted for relative sliding movement in the direction of the spindle axis to permit such withdrawal of the spindle.

Accordingly, in order to disassemble the valve, it is merely necessary to release the detent arrangement, withdraw the spindle and remove the valve member. - 2

In one embodiment of the invention, the detent arrangement is engageable with a groove or shoulder forming part of, or fixed relative to, the spindle, for example so as to enable rotation of the spindle but prevent longitudinal sliding of the spindle.

In another embodiment, the detent arrangement comprises an element that moves with the spindle and engages in a slot in the housing.

The detent arrangement is preferably held captive on the valve body and/or on the spindle whether or not the spindle is released, so that the detent arrangement cannot be mislaid.

In the case where a manually-operable handle is provided at one end of the spindle, the detent arrangement is preferably provided adjacent that end of the spindle. When the valve is installed in a crowded location, this is therefore likely to make the detent arrangement more easily accessible.

The detent arrangement may also be arranged to limit the rotational movement of the spindle and/or to lock the spindle releasably in its open and closed positions.

Preferably, the spindle engages in a passageway through the valve member. In this case, IS the spindle and the passageway are preferably formed with a complementary keyway and key, or with complementary splining, so that in use the valve member turns with the spindle, but so that the spindle can be slid out of the passageway.

The valve member may have a vane portion that is offset from the spindle axis. In the case where the passageway has a circular cross-section, the vane portion preferably has a peripheral sealing surface that is partspherical about a sphere axis that is generally coincident with the spindle axis. Accordingly, when the valve is closed, sealing can occur between the valve member and the valve body in a plane that is offset from the spindle axis so that the spindle does not interfere with the seal. By providing the part-spherical sealing surface, an effective seal can be achieved over a range of positions of the valve member, rather than merely in one precise position.

This latter feature may be provided independently of some of the other features of the first aspect of the invention. Accordingly, a second aspect of the invention provides a butterfly valve comprising a valve body having a circular cross-section passageway therethrough, a spindle mounted for rotation in the valve body about the axis of the spindle and extending across the passageway, and a butterfly valve member mounted in the passageway on the spindle for rotation with the spindle, the valve member having a vane portion arranged so that, in a closed position of the spindle, the vane portion extends in a direction across the passageway and, in an open position of the spindle, the vane portion extends in a direction along the passageway. The vane portion is offset from the axis of the spindle and has a peripheral sealing surface that is part-spherical about a sphere axis that is generally coincident with the spindle axis.

Preferably, the valve body has an annular groove offset from the axis of the spindle, and a resilient annular seal element is seated in the annular groove for sealing with a peripheral sealing surface of the vane portion when the spindle is in its closed position. In this case, the body is preferably formed with a hole extending to the root of the groove into which an element can be inserted to dislodge the seal element from the groove. This simplifies removal of the seal element and reduces the risk of damage to the seal during removal.

This latter feature may be provided independently of some of the other features of the second aspect of the invention. Accordingly, a third aspect of the invention provides a butterfly valve comprising a valve body having a passageway therethrough, a spindle mounted for rotation in the valve body about the axis of the spindle and extending across the passageway, and a butterfly valve member mounted in the passageway on the spindle for rotation with the spindle, the valve member having a vane portion arranged so that, in a closed position of the spindle, the vane portion extends in a direction across the passageway and, in an open position of the spindle, the vane portion extends in a direction along the passageway. The vane portion is offset from the axis of the spindle. The valve body has an annular groove offset from the axis of the spindle. A resilient annular seal element is seated in the annular groove for sealing with a peripheral sealing surface of the vane portion when the spindle is in its closed position, and the body is formed with a hole extending to the root of the groove into which an element can be inserted to dislodge the seal element from the groove.

Because the seal element is offset from the axis of the spindle, the seal element may be of uniform cross-section. In other words, a very simple design of seal element may be employed.

Specific embodiments of the present invention will now be described, purely by way of example, with reference to the accompanying drawings, in which: Figure 1 is a cross-sectioned side view of a first embodiment of butterfly valve, taken on the section line 1-1 in Figure 2A, with the valve closed; - 4 Figure 2A is a cross-sectioned plan view of the valve, taken on the section line 2-2 in Figure 1, with the valve in its closed position; Figure 2B is similar to Figure 2A, but with the valve in its open position; Figure 3A is a cross-sectioned end view of the valve, taken on the staggered section lines 3A-3A in Figures 2A and 4A, with the valve in its closed position; Figure 3B is an end view of the valve, as viewed in the direction 3B shown in Figure 2B, with the valve in its closed position; Figure 4A is an underplan view of the valve, as viewed in the direction 4 shown in Figure 3B, with the valve in a locked state; Figure 4B is similar to Figure 4A, but with the valve in an unlocked state; Figure 5 is an isometric view of part of the valve; Figure 6 is an isometric view of a second embodiment of butterfly valve; Figures 7A-7D show various positions of a detent system of used in the valve of Figure 6; and Figure 8 is an isometric view of a third embodiment of butterfly valve.

IS Referring to Figures I to 5 of the drawings, the first embodiment of butterfly valve 10 primarily comprises a valve body 12, an operating spindle 14, a valve member 16, a seal 18 and a locking clip 20.

The valve body 12 is cylindrical, defining a fluid passageway 22, and may be coupled in a fluid path by any suitable means such as screw-threading, push-fit or clip-fit. Part-way along its length, the wall of the body 12 is formed with diametrically opposite holes 24,26, the upper hole 24 being plain and the lower hole 26 being shouldered. Longitudinally adjacent the holes 24,26, the inner surface of the body 12 is formed with an annular groove 28. Parallel to the upper hole 24, a small diameter hole 30 extends through the wall of the body 12 to the root of the groove 28.

The spindle 14 is shaped and sized to fit in the holes 24,26 in the body 12 and has upper and lower grooves receiving O-rings 32,34 to seal the spindle 14 in the holes 24,26. The lower end of the spindle 14 projects from the body 12 and has an annular groove 36 in the projecting portion 37. The upper end of the spindle 14 projects from the body 12 and may be provided - s - with an operating handle or crank (not shown) or may be coupled to an electric actuator or the like (not shown) in a conventional manner. The spindle 14 has a keyway 38 (Figure 2A) extending part-way along its length from the lower end of its larger diameter portion.

The valve member 16 has a vane portion 40 and a raised mounting portion 42 formed diametrically across one side of the vane portion 40. The other side of the vane portion 40 has a recess 44 so as to reduce the weight of the valve member 16. A hole 46 extends diametrically through the mounting portion 42 to receive the spindle 14 and is formed part-way along its length with a key 48 (Figure 2A) that engages the keyway 38 of the spindle 14 so that the valve member 16 rotates with, but can slide relative to, the spindle 14. The peripheral surface SO of to the vane portion 40 is part-spherical, lying on a sphere indicated by dash-dot line 52 that is centred on the intersection 54 of the axes of the spindle 14 and the passageway 22, and that has a diameter that is a clearance fit for the diameter of the passageway 22.

The seal 18 is annular and is seated in the groove 28 in the body 12. The seal 18 is of the type known as a "D-seal" and is formed of any suitable material, but preferably of Viton.

synthetic rubber. The cross-section of the seal 18 is uniform all the way around the seal 18. The seal 18 and the groove 28 each have a depth that is substantially greater than their width so that the seal 18 is not easily dislodged from the groove 28. The face of the seal 18 is rounded and projects from the groove 28 so as to engage, with a degree of pressure, all around the peripheral surface SO of the valve member 16 when the valve 10 is closed.

When the valve 10 is assembled as shown in the drawings, the spindle 14 is locked in place by the clip 20. The clip 20 is of spring strip formed as shown in Figures 3A and 3B to have a central portion 56 and two wing portions 58 that generally follow the contour of the outer surface of the body 12, and two folded portions 60 that join the wing portions 58 to the central portion so as to enable the clip 20 to be grasped. Referring in particular to Figures 4A and 4B, the central portion 56 is formed with a keyhole having a hole 62 that is slightly larger in diameter than the projecting portion 37 at the lower end of the spindle 14 and a slot 64 that is slightly wider than the diameter of the groove 36 in the lower end of the spindle 14. The wing portions 58 of the clip 20 are each formed with bent slots 66. Headed pins 68 pass through the bent slots 66 into the valve body 12 to hold the clip 20 captive on the body 12.

In the position shown in Figure 4A, the slot 64 of the keyhole engages the groove 36 in the lower end of the spindle 14 to prevent removal of the spindle 14. From that position, the clip can be twisted anticlockwise and moved upwardly to the position shown in Figure 4B in which the hole 62 of the keyhole is aligned with the head 37 at the lower end of the spindle 14 - 6 so that the spindle 14 can be withdrawn from the body 12. Once the spindle has been withdrawn, the valve member 16 can then be removed from the body 12.

In order to dislodge the D-seal 18 from the groove 28, a piece of wire or the like can be inserted into the hole 30 in the body 12 and used to press part of the D-seal 18 out of the groove sufficiently that it can be grasped from within the passageway 22 and completely removed.

After cleaning of the parts of the valve 10, the parts may be reassembled in the reverse order.

It will be appreciated that many modifications and developments may be made to the first embodiment of the invention described above. For example, the locking clip 20 may alternatively be provided adjacent the upper end of the spindle 14, and other forms of releasable detent may alternatively be employed. However, the detent is preferably such that it can be released without requiring the use of a tool.

Referring now to Figures 6 to 7D, the second embodiment of butterfly valve 10 is similar to the first embodiment described above, except in the following respects.

A locking clip (20 in Figures l to 5) is not provided at the lower end of the spindle 14, and indeed the lower end of the spindle 14 does not project from the valve body 12, but instead is seated in a blind hole in the valve body 12 without the need for an O-ring (24 in Figures 1 to 5) around the lower end of the spindle 14.

A handle 70 projects generally at right angles from the upper end of the spindle 14 and has a first portion 72 that is fixed to the spindle 14 and a second portion 74 that is telescopically mounted on the first portion 72 and is urged by a spring (not shown) in the direction of the arrow 76 towards the spindle 14. A peg 78 projects downwardly from the second portion 74 of the handle 70. The lower end 80 of the peg 78 is enlarged and engages in a detent slot 82 formed in the valve body 12. The detent slot 82 is generally quarter-circular and has two notches 84 at its ends and extending towards the spindle 14 and a further notch 86 midway between its ends and extending away from the spindle 14. The edges of the slot 82 and end notches 84 have an undercut 88 to receive the enlarged lower end 80 of the peg 78. The further notch 86 is not undercut but is larger than the end notches 84.

Referring specifically to Figure 7A, when the valve 10 is open, the peg 78 is urged by the handle-spring into engagement with one of the end notches 84 to hold the valve 10 open, and the enlarged lower end 80 of the peg 78 engages in the undercut 88 to prevent the spindle 14 being withdrawn from or falling out of the valve body 12. In order to close the valve 10, the 7 second portion 74 of the handle 70 is manually pulled against the spring action away from the spindle 14 so that the peg 78 moves out of the end notch 84, and the handle 70 can then be manually swung a quarter of a turn clockwise, past the position shown in Figure 7B, to the other end of the slot 82, and the peg 78 can then engage in the other notch 84, as shown in Figure 7C, where the valve 10 is held closed and the spindle 14 is prevented by the enlarged lower end 80 of the peg 78 and the undercut 88 from being withdrawn from or falling out of the valve body 12. In order to remove the spindle 14 from the valve body 12 so that the valve 10 can be disassembled and cleaned, the handle 70 is moved to the position shown in Figure 7B, and the second portion 74 of the handle 70 is manually pulled further away from the spindle 14 so that the peg 78 and its enlarged lower end 80 move into the further notch 86 and so that the enlarged lower end 80 of the peg 78 disengages from the undercut 88 on the opposite side of the slot 82 to the further notch 86. This then enables the handle 70 to be lifted and the spindle 14 to be withdrawn from the valve body 12 and the valve member 16.

Referring now to Figure 8, the third embodiment of butterfly valve 10 is similar to the second embodiment described above, except in the following respects.

The handle 70 is integrally formed with the spindle 14; it is not telescopic and does not have a peg (78 in Figure 6). A disc 90 is fixed to the spindle 14 immediately above the valve body 12. The disc 90 is generally circular, but has a peripheral notch 92 extending around just over one quarter of a turn of the disc 90. A headed screw 94 is screwed into a hole in the valve body 12 and has a shaft (not shown) that engages in the notch 92 so as to limit turning movement of the spindle/handle 14, 70 to one quarter of a turn, the limits of the turning movement corresponding to the open and closed positions of the valve 10. The head of the screw 94 overlaps the disc 90 to prevent the spindle 14 being withdrawn from or falling out of the valve body 12. In order to remove the spindle 14 from the valve body 12 so that the valve 10 can be disassembled and cleaned, the screw 94 is removed, and the spindle 14 can then be withdrawn from the valve body 12 and valve member 16.

It will be appreciated that many modifications and developments may be made to the third embodiment of the invention described above. For example, the screw 94 may be replaced by a spring-loaded catch which normally engages in the notch 92 and overlaps the disc 90, but which can be manually slid against the spring action away from the spindle 14 so that the catch no longer overlaps the disc 90. - 8

It should be noted that the embodiments of the invention has been described above purely by way of example and that many other modifications and developments may be made thereto within the scope of the present invention. - 9 -

Claims

1. A butterfly valve comprising: a valve body having a passageway therethrough; a spindle mounted for rotation in the valve body about the axis of the spindle and extending across the passageway; and a butterfly valve member mounted in the passageway on the spindle for rotation with the spindle so that, in a closed position of the spindle, the valve member extends in a direction across the passageway and, in an open position of the spindle, the valve member extends in a direction along the passageway; wherein: a detent arrangement is provided for releasably holding the spindle in its position extending across the passageway; the spindle is mounted for sliding movement in the valve body so that, upon release of the detent arrangement, the spindle can be withdrawn from the valve body by movement in the direction of the spindle axis; and the valve member and spindle are mounted for relative sliding movement in the direction of the spindle axis to permit such withdrawal of the spindle.

2. A butterfly valve as claimed in claim 1, wherein the detent arrangement is engageable with a groove or shoulder forming part of, or fixed relative to, the spindle.

3. A butterfly valve as claimed in claim 1 or 2, wherein the detent arrangement comprises an element that moves with the spindle and engages in a slot in the housing.

4. A butterfly valve as claimed in any preceding claim, wherein the detent arrangement is held captive on the valve body and/or on the spindle whether or not the spindle is released.

5. A butterfly valve as claimed in any preceding claim, wherein a handle is provided at one end of the spindle, and the detent arrangement is provided adjacent that end of the spindle. -

6. A butterfly valve as claimed in any preceding claim, wherein the detent arrangement is also arranged to limit the rotational movement of the spindle.

7. A butterfly valve as claimed in any preceding claim, wherein the detent arrangement is also arranged to lock the spindle releasably in its open and closed positions.

8. A butterfly valve as claimed in any preceding claim, wherein the spindle engages in a passageway through the valve member.

9. A butterfly valve as claimed in claim 7, wherein the spindle and the passageway are formed with a complementary keyway and key, or with complementary splining.

10. A butterfly valve as claimed in any preceding claim, wherein the valve member has a vane portion that is offset from the spindle axis.

11. A butterfly valve as claimed in claim 10, wherein: the passageway has a circular cross-section; and the vane portion has a peripheral sealing surface that is part-spherical about a sphere axis that is generally coincident with the spindle axis.

12. A butterfly valve comprising: a valve body having a circular crosssection passageway therethrough; a spindle mounted for rotation in the valve body about the axis of the spindle and extending across the passageway; and a butterfly valve member mounted in the passageway on the spindle for rotation with the spindle, the valve member having a vane portion arranged so that, in a closed position of the spindle, the vane portion extends in a direction across the passageway and, in an open position of the spindle, the vane portion extends in a direction along the passageway; wherein: the vane portion is offset from the axis of the spindle; and - 11 the vane portion has a peripheral sealing surface that is part-spherical about a sphere axis that is generally coincident with the spindle axis.

13. A butterfly valve as claimed in any of claims 10 to 12, wherein: the valve body has an annular groove offset from the axis of the spindle; and a resilient annular seal element is seated in the annular groove for sealing with a peripheral sealing surface of the vane portion when the spindle is in its closed position.

14. A butterfly valve as claimed in claim 13, wherein the body is formed with a hole extending to the root of the groove into which an element can be inserted to dislodge the seal element from the groove.

15. A butterfly valve comprising: a valve body having a passageway therethrough; a spindle mounted for rotation in the valve body about the axis of the spindle and extending across the passageway; and a butterfly valve member mounted in the passageway on the spindle for rotation with the spindle, the valve member having a vane portion arranged so that, in a closed position of the spindle, the vane portion extends in a direction across the passageway and, in an open position of the spindle, the vane portion extends in a direction along the passageway; wherein: the vane portion is offset from the axis of the spindle; the valve body has an annular groove offset from the axis of the spindle; a resilient annular seal element is seated in the annular groove for sealing with a peripheral sealing surface of the vane portion when the spindle is in its closed position; and the body is formed with a hole extending to the root of the groove into which an element can be inserted to dislodge the seal element from the groove.

16. A butterfly valve as claimed in any of claims 13 to 15, wherein the seal element is of uniform cross-section. - 12

17. A butterfly valve, substantially as described with reference to the drawings.