The invention relates to a quarter-turn valve comprising a valve housing including a flow channel through which a fluid flow may be guided and a blocking element arranged to rotate between a closed and an open position in the fluid flow to block the fluid flow through the flow channel.

Background of the invention

Quarter-turn valves are a type of valves which enable the user to quickly actuate the valve by a quarter-turn of the operating handle - i.e. the operating handle is turned ninety degrees between fully open and fully closed positions. One of the most common types of quarter-turn valves are the ball valve but other quarter turn valves are also widely used - such as the butterfly valve, the plug valve, the eccentric plug valve and other.

Quarter-turn valves are typically manually operated - although actuated or motorized operation also exist - but with larger valves, or if the valve over time gets a little stuck, it can require a substantial torque to rotate the blocking element in the valve.

Thus, from United States patent no. US 9,377,121 B2 it is known to provide a quarter-turn valve with a worm gearing enabling that the valve can be operated with less torque. However, this requires that the valve is mounted on its side to allow ground level operation of a buried valve as disclosed in United States patent no. US 7,549,440 B l and this valve design is therefore quite space consuming, particularly with larger gear ratios.

An object of the invention is therefore to provide for an advantageous and more compact technique for actuating a quarter-turn valve. The invention

The invention provides for a quarter-turn valve comprising a valve housing including a flow channel through which a fluid flow may be guided. The quarter-turn valve further comprises a blocking element arranged to rotate between a first position, in which said blocking element allows flow through the flow channel, and a second position in which the blocking element blocks flow through the flow channel, and the valve comprises a stem arranged to actuate the blocking element through a gearing. The gearing of the quarter turn valve comprises a gear nut arranged to engage the stem so that when the stem and the gear nut are mutually rotated, the gear nut is displaced along the longitudinal direction of the stem, and a gear sleeve comprising a sleeve helical track, wherein the gear sleeve is connected to the blocking element. The gearing of the quarter turn valve also comprises a gear housing including a housing helical track, wherein the gear housing is fixed in relation to the valve housing, and wherein the gear nut is arranged to engage both the sleeve helical track and the housing helical track.

Forming the gear nut so that it engages both the sleeve helical track and the housing helical track is advantageous in that the rotation of the gear sleeve - connected to and driving the blocking element - is then geared by both helical tracks. I.e. in a relatively tight space the rotation of the gear sleeve can be geared by two helical tracks. Furthermore, by this design the enables that the rotational axis of the quarter turn blocking element is coaxial with the gearing (the rotational axis of the stem) further enabling a compact valve design. It should also be noted that in this context the term "the gear sleeve is connected to the blocking element" does both include directly and indirectly connected to the blocking element. I.e. the gear sleeve could be directly connected to the blocking element to rotate the blocking element in and out of the flow channel or the gear sleeve could be indirectly connected to the blocking element through a further part such as a blocking shaft. In an aspect of the invention, the gear sleeve comprises at least two sleeve helical tracks, wherein the gear housing comprises at least two housing helical tracks and wherein the gear nut is arranged to engage the at least two sleeve helical tracks and the at least two housing helical tracks.

Forming the gearing so that the gear nut engages at least two sleeve helical tracks and at least two housing helical tracks is advantageous in that the load on the nut, the sleeve and the housing can be more evenly distributed and in that the load can be distributed over a larger area.

In an aspect of the invention, the gear nut is arranged to extend through the sleeve helical track and into the housing helical track. Forming the helical track in the gear sleeve through-going so that the gear nut may extend through the sleeve helical track and into the housing helical track is advantageous in that this provide for a simple and compact gearing design. I.e. because the helical tracks can be formed radially overlapping the total vertical (longitudinal) extent of the gearing - particularly the gear sleeve and gear housing - can be reduced to form a compact gearing.

In an aspect of the invention, the stem comprises an externally threaded part arranged to engage an internally threaded part of the gear nut. Forming the stem and the nut so that they mutually engage through a threaded connection is advantageous in that this provides simple and efficient means for ensuring that when the stem (or the nut) is rotated, the nut is displaced along the longitudinal direction of the stem. In an aspect of the invention, the gear sleeve is arranged to enclose a part of the stem. Forming the gear sleeve so that it encloses at least a part of the stem is advantageous in that this enables a compact gearing design

In an aspect of the invention, the gear housing is arranged to enclose a part of the gear sleeve.

Forming the gear housing so that it encloses at least a part of the gear sleeve is advantageous in that this enables a compact gearing design

In an aspect of the invention, the gear sleeve is arranged to rotate inside the gear housing.

Arranging the gear sleeve so that it rotates inside the gear housing is advantageous in that the gear sleeve and bearings etc. enabling this mutual rotation hereby is better protected and in that this enables a more compact design.

In an aspect of the invention, the gear sleeve is made in a first material, wherein the gear nut is made in a second material and wherein the first material is different from the second material.

The nut will engage the sleeve through surfaces running against each other. Thus, to reduce wear and to reduce the risk of seizing and other types of mechanical damage it is advantageous to form the two contact surfaces in different materials - preferably materials of different hardness.

In an aspect of the invention, the gear nut is predominantly made from brass. Brass - such as the brass alloy sold under the trademark name "Eco Brass" - has good bearing properties and is easy to machine and it is therefore advantageous to form the gear nut predominantly from brass. In an aspect of the invention, the pitch of the sleeve helical track is substantially identical with the pitch of the housing helical track.

Forming the sleeve helical track and the housing helical track with a substantially identical pitch is advantageous in that the loads are hereby more evenly distributed.

In an aspect of the invention, the pitch of the sleeve helical track and the pitch of the housing helical track are substantially constant.

Forming the sleeve helical track and the housing helical track with substantially constant pitch is advantageous in that the loads are hereby more evenly distributed.

In an aspect of the invention, the sleeve helical track and the housing helical track spiral in opposite directions. Forming the pitch of the sleeve helical track and the housing helical track in opposite directions is advantageous in that the gearing effect hereby is increased.

The invention further provides for use of a quarter-turn valve according to any of the above-mentioned quarter-turn valve as a valve.

Hereby is achieved an even more advantageous embodiment of the invention.

In an aspect of the invention, the gear sleeve and the stem are coaxially arranged to ensure simple and precise operation of the valve. In an aspect of the invention, the gear sleeve and the stem are formed as two separate individual parts to ensure simple and precise operation of the valve.

In an aspect of the invention, the gear sleeve and the stem are connected through a blocking shaft.

Connecting the gear sleeve and the stem through a blocking shaft is advantageous, in that it enables that the gearing and the blocking element may be spaced further apart and in that it enables further advantageous quarter turn valve designs.

It should be noted that the blocking shaft at least partly could be an individual part or it could be formed integrally with the gear sleeve and/or the stem.

Figures

An embodiment of the invention will be described, by way of non-limiting example, in the following with reference to the figures in which: illustrates a cross section through the middle of quarter- turn valve in the form of a ball valve in open position, as seen from the side, fig. 2 illustrates a cross section through the middle of the bottom part of the quarter-turn valve disclosed in fig. 1, as seen from the side, fig. 3 illustrates a cross section through the middle of a quarter- turn valve in the form of an eccentric plug valve, as seen from the side, fig. 4 illustrates a gear housing, as seen in perspective, fig. 5 illustrates a gear nut, as seen in perspective, fig. 6 and illustrates a gear sleeve, as seen in perspective, and fig. 7 illustrates a gearing of a quarter-turn valve, as seen in perspective.

Detailed description

Fig. 1 illustrates a cross section through the middle of quarter-turn valve 1 in the form of a ball valve in open position, as seen from the side, and fig. 2 illustrates a cross section through the middle of quarter-turn valve 1 in the form of a ball valve in closed position, as seen from the side. With quarter-turn valves 1, it is important that the flow through the flow channel 21 is substantially unobstructed, primarily to minimize pressure drop but also to make the quarter turn valve 1 more insensitive to hard particles and other objects in the medium flowing through the valve 1. A quarter-turn valve also offers easy insertion and retrieval of pipe inspection and maintenance equipment.

In this embodiment, the quarter-turn valve 1 comprises a valve housing 2 through which the fluid flows when the quarter turn valve 1 is open.

In this embodiment, the flow channel 21 is substantially horizontal but in another embodiment, the flow channel 21 could be arranged slanted or even vertical.

In this embodiment, the fluid flow through the flow channel 21 can optionally be blocked by means of a blocking element 3 arranged in or at least around the flow channel 21. In this embodiment the blocking element 3 is a blocking ball 13 comprising a through bore 16 enabling through flow when the valve 1 is open. In this embodiment, the valve 1 comprises a stem 4 including an interaction part 14 arranged at the upper end of the stem 4. In this embodiment, the interaction part 14 is formed with an external conical square shape so that the stem 2 may be engaged and manually operated by means of a matching key (not shown). However, in another embodiment, the interaction part 14 could be formed with another shape - such as triangular, polygonal, oval or other - and/or the interaction part 14 could also or instead be arranged internally in or at the end of the stem 2. Also, in another embodiment the stem 4 could be operated automatically by means of a rotating actuator such as a motor driving the rotation of the stem 4.

In this embodiment, the stem 4 extends almost all the way down to a blocking shaft 22 connected to the blocking element 3 but in another embodiment, it could stop earlier and it is important to note that the stem 4 and the blocking shaft 22 and/or blocking element 3 are two individual and separate parts although they are arranged coaxially.

In this embodiment the stem 4 engages a gear nut 6 through external thread 11 on the stem 4 meshing with matching internal thread 12 on the gear nut 6. The stem 2 is longitudinally fixed - among other through a bearing arrangement 15 - so that the stem 4 may be rotated but it cannot be axially displaced.

In this embodiment, the gear nut 6 extends into the sleeve helical track 8 of an enclosing gear sleeve 7 and further into a housing helical track 10 in a further enclosing gear housing 9.

However, in another embodiment the nut 6 could be arranged to engage the sleeve helical track 8 and the housing helical track 10 by separate means e.g. by means of arms engaging sleeve helical track 8 and other arms reaching past the gear sleeve 7 and into the housing helical track 10. In this embodiment the gear sleeve 7 is rigidly connected to the blocking element 3 through the blocking shaft 22 but in another embodiment the gear sleeve 7 could be connected directly to the blocking element 3 and the blocking shaft 22 could be omitted.

In this embodiment, the gear sleeve 7 is axially fixed but free to rotate while the gear housing 9 and thereby the housing helical track 10 is fixed against both axial displacement and rotation. Thus, the nut 6 is rotationally locked against rotation by the housing helical track 10 so that when the stem 4 is rotated the meshing threaded parts 11, 12 will result in the nut 6 being displaced axially - i.e. vertically in the present embodiment - while being forced to follow the curvature of the housing helical track 10 so that the nut 6 is forced to rotate a little as it is forced up or down. In turn the nut 6 will drive a rotation of the gear sleeve 7 - both by the axial displacement of the nut 6 and the rotation generated by the nut 6 engaging the housing helical track 10 - and since the gear sleeve 7 is also provided with a sleeve helical track 8, the axial motion of the nut 6 will force the gear sleeve 7 to rotate (even if the housing helical track 10 was just a straight vertical track).

In this embodiment, the gear sleeve 7 is rigidly connected to the blocking shaft 22 which in turn is rigidly connected to the blocking element 3. I.e. when the gear sleeve 7 is rotated it will rotate the blocking shaft 22 which in turn will rotate the blocking element 3 to block or open flow through the quarter turn valve 1.

Thus, through this design the axial displacement of the gear nut 6 will generate double rotation of the gear sleeve 7 from both the sleeve helical track 8 and the housing helical track 10 so that the pitch of the helical tracks 8, 10 may be formed relatively steep without increasing the vertical extent of the blocking arrangement 13. Thus, through this design the blocking arrangement 13 can be formed both durable, simple, efficient and compact.

In this embodiment, the pitch of the sleeve helical track 8 and the housing helical track 10 is approximately 300 mm per rotation all the way - i.e. in this embodiment the pitch of the sleeve helical track 8 is substantially identical to the pitch of the housing helical track 10 and the pitch of the sleeve helical track 8 and the housing helical track 10 are substantially constant all the way. However, in another embodiment the pitch of the sleeve helical track 8 and/or the housing helical track 10 could be smaller - such as 250, 200, 150 mm/rotation or even smaller - and/or the pitch of the sleeve helical track 8 and/or the housing helical track 10 could be bigger - such as 350, 400, 500 mm/rotation or even bigger - e.g. adapted to the specific material of the nut 6, the sleeve 7 and/or the housing 9 and/or the specific use and/or the pitch of the sleeve helical track 8 and/or the housing helical track 10 could be varying.

Thus, in this embodiment the sleeve helical track 8 and the housing helical track 10 are substantially identically except the fact that they spiral in opposite directions so that the resulting rotation of the gear sleeve 7 in principle is doubled as opposed to if the gear nut 6 did only engage the sleeve helical track 8.

In this embodiment, the gearing 5 only comprises a single gear nut 6 but in another embodiment, the gearing 5 could comprise two, three, four or even more gear nuts 6 either interconnected or arranged separately.

An alternative to the ball valve could be a plug valve where the ball instead is formed as a cylinder or a cone comprising a through opening arranged perpendicularly to the rotational axis of the cylinder or cone. Fig. 3 illustrates a cross section through the middle of a quarter-turn valve 1 in the form of an eccentric plug valve, as seen from the side.

In this embodiment, the blocking element 3 in the quarter-turn valve 1 is a so-called eccentric plug 17 where the actual blocking face is displaced in relation to the rotational axis, so that when the plug 17 is turned 90 degrees to fully open the valve 1 (in fig. 3 the eccentric plug 17 is shown in closed position), the plug 17 is rotated substantially fully out of the flow channel. E.g. as opposed to a quarter turn butterfly valve (not shown) where the blocking disc coincides with the rotational axis so that the blocking disc will be present in the flow channel both in closed and open state.

Typically, quarter turn valves such as the ball valve disclosed in figs. 1 and 2 will only be supported at one side - i.e. the side where it is connected to the gear sleeve 7. However, quarter turn valves 1 such as eccentric plug valves, plug valves and butterfly valves will typically be supported on both sides of the blocking element 3 - as disclosed in fig. 3 where the eccentric plug 17 is supported both where it is connected to the gear sleeve 7 through a blocking shaft 22 and by a tilting joint 18 arranged on the opposite side of the blocking element 3. In this embodiment the fluid flowing through the valve 1 is water but in another embodiment, it could be fuel, slurry, juice or another liquid or oxygen, C02, nitrogen or any other kind of gas.

Fig. 4 illustrates a partial cross section through a gear housing 9, as seen in perspective.

In this embodiment, the housing helical track 10 is formed integrally in the inside wall of the gear housing 9. However, in another embodiment at least some of the housing helical track 10 could be formed in a separate part inserted into and rigidly connected to the rest of the gear housing 9. In this embodiment, the gear housing 9 is provided with mounting holes 19 enabling that the gear housing 9 can be rigidly fixed to the rest of the quarter turn valve 1 by means of bolts, so that the position of the gear housing 9 - and thereby the housing helical track 10 - is fixed in relation to the valve housing 2.

However, in another embodiment the gear housing 9 can be rigidly fixed to the rest of the quarter turn valve 1 by other means - such as rivets, welding, adhesive and/or other and/or the gear housing 9 and the valve housing 2 could be more or less integrally formed.

In this embodiment, the gear housing 9 is made entirely from cast iron enabling simple and inexpensive manufacturing of this relatively complex part. However, in another embodiment the housing 9 could only predominantly be made from cast iron or the housing 9 could also or instead be made from another material such as stainless steel, plastic, a composite material, aluminium, brass or other.

Fig. 5 illustrates a gear nut 6, as seen in perspective. In this embodiment, the gear nut 6 is provided with substantially flat sliding surfaces 20 matching the pitch of the respective helical tracks 8, 10 that the surfaces 20 engage. However, in another embodiment the gear nut 6 could be designed differently - e.g. with round, oval or polygonal surfaces 20. In this embodiment, the gear nut 6 is made entirely from brass providing good bearing qualities when being driven against the matching surfaces of the sleeve helical track 8 and the housing helical track 10. However, in another embodiment the nut 6 could predominantly be made from brass or the nut 6 could also or instead be made from another material such as stainless steel, plastic, a composite material, ceramic or other. Fig. 6 illustrates a gear sleeve 7, as seen in perspective.

In this embodiment, the gear sleeve 7 is made entirely from cast stainless steel enabling simple and inexpensive manufacturing of this relatively complex part while at the same time ensuring that the sleeve 7 is more durable. However, in another embodiment the gear sleeve 7 could only predominantly be made from stainless steel or the sleeve 7 could also or instead be made from another material such as cast iron, plastic, a composite material, aluminium or other.

In the embodiment disclosed in fig. 1-6 the gearing 5 is disclosed where the gear sleeve 7 comprises two sleeve helical tracks 8, the gear housing 9 comprises two housing helical tracks 10 and the gear nut 6 is arranged to engage both sleeve helical tracks 8 and both housing helical tracks 10 at once.

However, in another embodiment the gear sleeve 7 would comprise another number of sleeve helical tracks 8 - such as one, three, four or even more -, the gear housing 9 would comprise another number of housing helical tracks 10 - such as one, three, four or even more - and the gear nut 6 would then be arranged to engage the corresponding number of helical tracks 8, 10.

Fig. 7 illustrates an assembled gearing 5 for a quarter-turn valve 1, as seen in perspective. In this embodiment the housing helical tracks 10 are reflected on the outside of the wall of the gear housing 9 but in another embodiment the housing helical tracks 10 could only be identified in the inside of the wall of the gear housing 9.

The invention has been exemplified above with reference to specific examples of quarter turn valves 1, blocking elements 3, gearing sleeves 7 and other. However, it should be understood that the invention is not limited to the particular examples described above but may be designed and altered in a multitude of varieties within the scope of the invention as specified in the claims.

List

1. Quarter turn valve

2. Valve housing

Blocking element

4. Stem

5. Gearing

6. Gear nut

7. Gear sleeve

8. Sleeve helical track

9. Gear housing

10. Housing helical track

11. Externally threaded part of stem

12. Internally threaded part of gear nut

13. Blocking ball

14. Interaction part

15. Bearing arrangement

16. Through bore

17. Eccentric plug

18. Tilting joint

19. Mounting hole

20. Sliding surface

21. Flow channel

22. Blocking shaft