An adjustable regulator insert

The invention concerns an adjustable regulator insert for valves according to the preamble of claim 1.

Such inserts for valves are known from WO 95/12082 where the area of the inlet area is adjustable by having two plates arranged close together with a number of holes, where the plates can be rotated around one common axis. The area of the inlet opening is then the area of the regions where holes in both of the two individual plates overlap such that a fluid may pass directly through the two plates. The area of the inlet opening may be adjusted by rotating one of the plates into a position where e.g. the holes in one plate partly faces holes in the other plate and partly faces the other solid plate to an extend where the needed area of the inlet opening is achieved. The setting of the area of the inflow opening is applied for advance setting of the desired constant flow through the insert.

Furthermore, the insert according to WO 95/12082 is configured with a roller membrane that closes off the outflow openings to a smaller or larger degree in response to variation in pressure across the insert, so as to accomplish an essentially constant flow of liquid through the insert.

Often it is necessary to preset this type of inserts for valves to a given maximum flow depending on the installation of which the insert is a part, e.g. for protecting other components. At the same time it is necessary to provide a possibility for automatically adjusting the flow between a minimum flow and this maximum set flow. This automatic adjustment could be in relation to a temperature measurement.

It has been found that this objective can be achieved with simple and reliable means by an insert according to the characterizing part of claim 1.

One advantage of the invention is that the two operations: 1 ) the setting of the maximum flow and 2) the continuous adjustment (e.g. performed automatically) are both performed by the same mechanical means which offers the possibility of a simple and reliable construction.

In the following the invention will be described in further details with reference to the figures.

Figure 1 shows an adjustable regulator insert for a valve according to an embodiment of the invention.

Figure 2 shows a cross sectional view of an adjustable regulator insert for a valve according to an embodiment of the invention.

Figure 3 illustrates the inner part of the means defining the area of the inlet opening of the insert.

Figure 4 illustrates a cross sectional view of the inner part of the means defining the area of the inlet opening of the insert.

Figure 5 illustrates an outer cup shaped part of the insert.

Figure 6 illustrates a cross sectional view of the outer cup shaped part of the insert.

Figure 7 illustrates the principle in an embodiment of the invention with the two plate shaped elements each having an opening.

Figure 8 illustrates a partly exploded view of the insert with a valve housing.

Figure 9 illustrates details of a bayonet socket for connecting a mounting part of the insert to a cup shaped part.

The adjustable regulator insert shown in figure 1 comprises a cup shaped part 2 having inlet openings 10 and outlet openings 20 for the fluid, typically water (e.g. for heating or cooling purposes), and a mounting part 3 e.g. having a thread 4 for placing and securing the insert 1 in a valve housing (not shown). The mounting part 3 is often made from a metal, e.g. brass, while the cup shaped part 2 is often made from a plastic material. The two parts may be connected by a bayonet socket (to be described below according to figure 9).

The insert has sealing means, e.g. an O-ring, for sealing the inflow from the outflow, when the insert is placed in a valve housing. The insert furthermore, comprise adjustments means 5 and 6 adjusting the area of the inflow openings 10. The first adjustment means 5 is moveable in the vertical direction of figure 1 , i.e. along the longitudinal axis of the insert 1. This adjustment means 5 is used for adjusting the area of the inflow openings in one direction. The second adjustment means 6 is rotatable around the longitudinal axis of the insert. This second adjustment means is used for adjusting the area of the inflow openings in a second direction. The two adjustment means 5 and 6 can be operated in different ways, i.e. one or both could be operated by an electrical actuator or a motor, or, one or both could be operated manually.

In the cross sectional view of a regulator insert shown in figure 2 it is seen that the adjustment means 5 and 6 are in engagement through a drive mechanism 31 with a central shaft 30 of the insert. The drive mechanism 31 will transfer both a rotational movement of the second adjustment means 6 and a displacement of the first adjustment means 5 to the central shaft 30 of

the insert. The displacement of the first adjustment means 5 is transferred to the shaft 30 without displacing the second adjustment means 6.

The central shaft 30 continuous towards the bottom 25 of the cup shaped part 2. In the cup shaped part 2 the central shaft 30 is connected to an inner basically cylindrical shaped part 35 (see also figure 3 and 4), which will be rotated with rotation of the shaft 30 and displaced in the longitudinal direction of the insert with a displacement of the shaft. This inner cylindrical shaped part is provided with flow passages 15, which flow passages 15 together with flow passages 16 in the cup shaped part 2 defines the area of the inlet openings 10, of which the area is varied by moving the two sets of flow passages in relation to each other such that they will overlap to a smaller or larger extend. This is described in further details below with reference to figures 3 - 7.

Figure 2 also illustrates the mechanisms for regulating the effective area of outflow openings 20. This mechanism is described in further details in WO 95/12082 and in WO 2005/038314. The mechanism is a part of the flow regulating function of the insert where displacement of the inflow in one direction is applied for setting a maximum flow, and displacement in a second direction is used for setting the actual flow, while the mechanism at the outflow openings 20 is used for ensuring a constant flow despite variations in the pressure difference across the insert.

The mechanism provides a roller membrane 21 at the outflow openings which closes off the outflow openings to a larger or smaller degree, in response to the pressure conditions across the insert. The spring 22 will press the roller membrane 21 away from the outflow openings such that these will be fully open when there is no pressure drop across the insert. The pressure of the fluid at the inlet openings 10 is transferred to the space 23 behind the roller membrane 21 through a passage in the central shaft 30, e.g.

from an opening in the bottom 25 of the cup shaped part. When the roller membrane 21 is in balance, the force exerted from the pressure drop across the insert will equals the force from the spring 22. An increased pressure drop will therefore press the roller membrane 21 downwards (in relation to figure 2) and thereby reducing the effective output opening area, while the spring 22 will force the roller membrane upwards (in relation to figure 2) at a reduced pressure drop. Thereby, this mechanism will provide a more constant flow through the insert.

Figure 2 furthermore illustrates that the insert 1 comprise a second spring 11 acting on the combined central shaft 30 and inner cylindrical shaped part 35 in order to press this upwards (in relation to figure 2) such that the first adjustment means 5 is pressed in the direction out of the insert 1. Therefore, when the insert is in use, means such as an actuator needs to be provided for pressing the first adjustment means 5 into the needed position and hold it there, such that the inlet opening will achieve the needed area. If the first adjustment means 5 is not pressed into position, e.g. by an actuator, the inlet opening will ( in a standard version of the insert) due to the pressure of the second spring 11 be pressed to be fully open in the direction controlled by the first adjustment means 5.

Figure 3 shows the combination of the central shaft 30 and the inner basically cylindrical shaped part 35 of the inner part defining the area of the inlet openings of the insert. The two parts will preferably have their longitudinal axis in common, and will be connected by one or a few bridging elements (not shown). The inner cylindrical part will at its outer surface preferably be provided with recesses 36 for placement of sealing means, such as O-rings. These will preferably provide a leak-tight connection to the cup shaped part 2, which is an outer cylindrical part.

It is also seen from figure 3 that the top part of the shaft 30 is provided with slots 37 for engaging with the drive mechanism 31. The first adjustment means 5 are movable within the second adjustment means 6. The first adjustment means will be able to displace the shaft 30, such that engagement means (not shown) of the second adjustment means 6 will stay in engagement with said slots 37. The engagement means will simply be displaced within the slots 37.

Figure 4 shows a cross sectional view of the inner cylindrical part 35 of the section A-A in figure 3. This illustrates two inlet flow passages 15. It is seen that these flow passages 15 is having a length extending along the periphery of the inner cylindrical part 15, and a width extending in a direction substantially parallel with the directional axis of the shaft 30. Often the length of the inlet flow passages will extend 90 - 180 degrees around the 360 degree periphery of the cylinder, preferably the length of the inlet flow passages will extend 120 - 160 degrees, and even more preferably it will extend approximately 140 degrees around the periphery of the cylinder.

Figure 5 shows the cup shaped part 2 with one visible flow passage 16 for inlet, and a number of outlet openings 20. It is seen that the outlet openings 20 differ in their length, which has the effect that the roller membrane 21 will not be able to close the outlet openings 20 completely and momentarily. This will help in avoiding pulsations in the flow system of which the regulator insert is a part. Figure 6 shows a cross sectional view of the cup shaped outer part 2 of the insert.

Figure 7 illustrates the basic principle of adjustment of the inlet area according to a preferred embodiment of the invention where a first plate shaped element 2', comprising a first flow passage 16', and a second plate shaped element 35' comprising a second flow passage 15' are displaceable relative to each other. The second plate shaped element 35' is displaceable

in the X direction indicated in figure 7, and independently of this displacement it can also be moved in a rotational direction Y indicated in figure 7.

The active area of the inlet opening 10' through which the fluid will flow is defined by the overlapping area of the first 16' and the second 15' flow passages.

The plate shaped elements could have any shape but are preferably cylindrically shaped. The important issue is that the two plate shaped elements can be displaced independently in two directions, such that when you have adjusted the displacement between the first 16' and the second 15' flow passages, a maximum obtainable overlapping area is defined.

Figure 8 illustrates how the cup shaped part 2 of the insert and the mounting part 3 of the insert is mounted in a valve housing 8. The parts may be assembled by a thread, by clicking means or by a bayonet socket (i.e. a bayonet joint). Preferably the cup shaped part 2 the mounting part 3 are assembled by a bayonet socket.

Figure 9 illustrates such a bayonet socket where the mounting part 3 of the insert is having a ring part 40 in the end which is to be connected to the cup shaped part 2. This ring part has protrusions 41 extending along the periphery of the ring part 40. Preferably the ring part 40 is provided with at least two protrusions 41 , where two protrusions 41 is the preferred embodiment.

The upper circular part (facing the mounting part 3) of the cup shaped part 2 is provided with a number of recesses 42 equal to the number of protrusions 41 in the ring part 40. The recesses are formed slightly conical such that the inner radius of the recess 42 in relation to the centre axis of the cup shaped part 2, is larger at the top part 44 of the recess 42 than the equivalent inner

radius at the bottom part 45 of the recess 42. This means that when the mounting part 3 (made from a metal) is inserted into the cup shaped part 2 (made from a plastic material), the protrusions 41 of the mounting part 3 will exert a pressure on the upper part of the cup shaped part 2 as the protrusions 41 are moved from the top part 44 of the recesses towards the bottom part 45 of the recesses 42.

In connection to the bottom part 45 of the recess 42 a slot 43 is provided. The protrusion 41 can, when reaching the bottom 45 of the recess 42, be entered into this slot by a rotational movement of the mounting part 3 in relation to the cup shaped part 2, where the rotational movement is in relation to the longitudinal axis of the insert.

As the inner radius in the slot 43 in relation to the centre axis of the cup shaped part 2, is larger than the equivalent inner radius at the bottom part 45 of the recess 42, the protrusion 41 will be locked in the position when it has been fully entered into the slot 43. This locking is due to the slight expansion of the cup shaped part 2 when the protrusions 41 are situated at the bottom part 45 of the recesses 42. The expansion is possible because of some elasticity in the plastic material from which the cup shaped part 2 is made. When the protrusion 41 is moved from the bottom part 45 of the recess 42 and into the slot 43, the expansion disappears.

When the insert 1 is placed in the valve housing 8 a close fitting between this upper part of the cup shaped part 2 and the valve housing 8 ensures that the upper part of the cup shaped part 2 will not be able to expand. The valve housing will prevent such expansion. Therefore, the bayonet socket assembling the mounting part 3 and the cup shaped part 2 will be kept in a locked position as long as the insert is placed in the valve housing 8.