MIXING VALVE AND HEATING OR COOLING SYSTEM

Abstract

A mixing valve having a first inlet port (4), a second inlet port (6) extending transverse to said first inlet port (4) and an outlet port (8). The inlet ports (4, 6) open out into a valve chamber (10) and the outlet port (8) branches off this valve chamber (10), inside which a movable valve element (12) is arranged, having an obstruction (32) inside the second inlet port (6), which protrudes from an inner circumference (36) of the second port (6) into an interior thereof. The obstruction (32) extends at least along a portion of the inner circumference (36), which portion of the circumference (36) is located on an inner side of the second inlet port (6) being distant from the first inlet port (4). A heating or cooling device includes such a mixing valve.

Claims

1. A mixing valve comprising: a first inlet port; a second inlet port extending transverse to said first inlet port; an outlet port, wherein the inlet ports open out into a valve chamber and the outlet port branches off the valve chamber; a movable valve element arranged inside the valve chamber; and an obstruction inside the second inlet port, the obstruction protruding from an inner circumference of the second inlet port into an interior of the second inlet port, and extending along at least a portion of the inner circumference, which portion of the inner circumference is located on an inner side of the second inlet port that is distant from the first inlet port.

2. A mixing valve according to claim 1, wherein the first inlet port and the outlet port are arranged on opposite sides of the valve chamber with the second inlet port being arranged between the first inlet port and the outlet port.

3. A mixing valve according to claim 1, wherein the obstruction is arranged in a half of the inner circumference of the second inlet port located on an inner side of the second inlet port that is distant from the first inlet port.

4. A mixing valve according to claim 1, wherein the obstruction extends along the inner circumference of the second inlet port in an angle greater 90°.

5. A mixing valve according claim 1, wherein: the obstruction has a first surface on a downstream side, downstream with respect to a flow direction along a longitudinal axis of the second inlet port; the first surface extends angled with respect to the longitudinal axis of the second inlet port.

6. A mixing valve according to claim 5, wherein the first surface is angled for a flow direction at an angle between 15° and 90° with respect to the longitudinal axis.

7. A mixing valve according to claim 1, wherein the obstruction and an adjacent circumferential wall define a pocket area on a downstream side of the obstruction.

8. A mixing valve according to claim 1, wherein a radial extent of the obstruction with respect to the longitudinal axis of the second inlet port is in the range of 3% to 25% of an inner diameter of the second inlet port.

9. A mixing valve according claim 1, wherein a distance between an outer circumferential surface of the valve element, with the second inlet port closed, and a free end of the obstruction closest to the valve element is in a range between zero and a length of the inner diameter of the second inlet port.

10. A mixing valve according to claim 1, wherein the obstruction is at least partly arranged on an insert which is inserted into the second inlet port.

11. A mixing valve according to claim 1, wherein at least a portion of the obstruction is integrally formed with a valve element comprising a valve seat for the valve element.

12. A mixing valve according to claim 1, wherein at least a portion of the obstruction is integrally formed with at least a portion of a valve housing defining the second inlet port.

13. A mixing valve according to claim 1, wherein the cross-section of the second inlet port is enlarged upstream of said obstruction.

14. A mixing valve according to claim 1, wherein the valve element is ball shaped.

15. A mixing valve according to claim 1, further comprising a temperature sensor arranged on or in the second inlet port, upstream of the obstruction.

16. A heating or cooling system comprising mixing valve, the mixing valve comprising: a first inlet port; a second inlet port extending transverse to said first inlet port; an outlet port, wherein the inlet ports open out into a valve chamber and the outlet port branches off the valve chamber; a movable valve element arranged inside the valve chamber; and an obstruction inside the second inlet port, the obstruction protruding from an inner circumference of the second inlet port into an interior of the second inlet port, and extending at least along a portion of the inner circumference, which portion of the inner circumference is located on an inner side of the second inlet port that is distant from the first inlet port, wherein the first inlet port and the second inlet port are configured to deliver fluid flows of different temperature and in at least one operational condition the flow through the second inlet port is lower than the flow through the first inlet port.

17. A heating or cooling system according to claim 16, further comprising: a heat source; and a return line of at least one heating or cooling circuit, wherein the first inlet port is connected to the heat source and the second inlet port is connected to the return line.

18. A heating or cooling system according to claim 16, wherein the first inlet port and the outlet port are arranged on opposite sides of the valve chamber with the second inlet port being arranged between the first inlet port and the outlet port.

19. A heating or cooling system according to claim 16, wherein the obstruction extends along the inner circumference of the second inlet port in an angle greater 90°.

20. A heating or cooling system according to claim 16, wherein: the obstruction has a first surface on a down-stream side, downstream with respect to flow direction along a longitudinal axis of the second inlet port; and the first surface extends angled with respect to the longitudinal axis of the second inlet port.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In the drawings:

[0028] FIG. 1 is a cross sectional view of a mixing valve according to a first embodiment of the invention;

[0029] FIG. 2 is a schematic top view of a mixing valve according to the invention;

[0030] FIG. 3 is a cross sectional view of a mixing valve according to a second embodiment;

[0031] FIG. 4 is a cross sectional view of a mixing valve according to a third embodiment;

[0032] FIG. 5 is a cross sectional view of a mixing valve according to a fourth embodiment;

[0033] FIG. 6 is a cross sectional view of a mixing valve according to a fifth embodiment; and

[0034] FIG. 7 is a schematic diagram of a heating device comprising a mixing valve.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0035] Referring to the drawings, in all the shown embodiments the mixing valve comprises a valve housing 2 defining a first inlet port 4, a second inlet port 6 and an outlet port 8. The two inlet ports 4 and 6 and the outlet port 8 are connected to a valve chamber 10 inside the valve housing 2. This means the two inlet ports 4 and 6 open out into the valve chamber 10 and the outlet port 8 branches off this valve chamber 10. Inside the valve chamber 10 there is arranged a movable valve element 12, which in this embodiment is ball-shaped. The valve element 12 comprises an opening or cut out 14 enabling a flow path from the first inlet port 4 and/or the second inlet port 6 towards the outlet port 8. In the shown position of the valve element both inlet ports 4 and 6 are open towards the outlet port 8, such that two flows from the inlet ports 4 and 6 are mixed in the valve chamber. The ball-shaped valve element 12 in this embodiment is rotatable about a rotational axis R extending normal to the plane of the figures. The valve element 12 may be rotatable about the axis R by a drive motor 16 as schematically shown in FIG. 7. Depending on the rotational position of the valve element 12 the first inlet port 4 can be fully closed or the second inlet port 6 can be fully closed. In intermediate positions the two inlet ports can be partly open with changing flow ratio depending on the rotational position of the valve element 12.

[0036] The mixing valve as shown in FIGS. 1 to 6 can for example be used in a heating circuit or system as shown in FIG. 7. In this example the mixing valve 18 is connected to a heat source 20, for example a boiler, and a heating circuit 22, for example a floor heating circuit of a building. In the feed line towards the heating circuit 22 there is arranged a circulator pump 24 for providing a fluid flow through the heating circuit 22. The outlet port 8 of the mixing valve 18 is connected to this feed line of the heating circuit 22. The first inlet port 4 of the mixing valve 18 is connected to an outlet of the heat source 20 and the second inlet port 6 of the mixing valve 18 is connected to a return line 26 of the heating circuit 22. The return line 26 is connected to the inlet of the heat source 20. A connection to the second inlet port 16 branches off this return line 26. The mixing valve 18 allows to admix a return flow from the return line 26 via the second inlet port 6 into a fluid flow of heating medium or fluid from the heat source 20 to adjust the temperature in the feed line of the heating circuit 22. By admixing fluid from the return line the temperature can be reduced in known manner. A similar design can be used for a cooling circuit. In a cooling circuit the heat source 20 would be replaced by a cooling device. In case of a cooling system, thus, warm water from the return line 26 would be admixed to the flow of cool water to adjust the temperature.

[0037] For the control of the mixing valve there is arranged at least one temperature sensor 28 at least inside the second inlet port 6. Detecting the temperature inside the second inlet port 6 may be problematic in case that the fluid flow or pressure inside the first inlet port 4 is higher than in the second inlet port 8. Under these circumstances there may occur the problem that a fluid flow from the first inlet port enters into the second inlet port 6 against or upstream the usual flow direction 30 inside the second inlet port 6. This would influence the temperature detected by temperature sensor 28. To reduce or eliminate this problem, there is arranged an obstruction 32 inside the second inlet port 6. In the embodiments shown in FIGS. 1 and 3 to 6 the obstruction 32 is ring-shaped extending along the entire inner circumference of the second inlet port 6 about the longitudinal axis X in flow direction 30. However, as explained with reference to FIG. 2 it would be sufficient to arrange the obstruction 32 on one side of the inner circumference of the second inlet port 6 only. The obstruction 32 should be arranged at least on the inner side which is distant from the first inlet port 4, i.e. on the side of the inlet port 6, which is closer to the outlet port 8. In these preferred embodiments the first inlet port 4 and the outlet port 8 extend along the same longitudinal axis Y, with the second inlet port 6 extending transverse. This means, when seen in FIG. 2 the obstruction 32 is arranged on a diameter side, with reference to the longitudinal direction X, of the second inlet port 6, which is away from the side on which the first inlet port 4 is located. The obstruction 32 is arranged on the side towards the outlet port 8. Thus, the obstruction 32 is arranged on a inner side of the second inlet port 6 which is facing the first inlet port 4. Thus, a fluid flow from the first inlet port 4 would primarily impinge on the side opposite, i.e. facing the first inlet port 4 which is the side with the obstruction 32. Thus, the obstruction 32 can influence a fluid flow entering from the first inlet port 4 into the second inlet port 6. Preferably, the obstruction 32 extends at least along an angle of 90° about the longitudinal axis X, preferably at least along an angle of 180° and further preferred along the entire circumference as shown in the other figures.

[0038] The obstruction 32 as shown, is angled with respect to the longitudinal axis X such that it forms a pocket-like area 34 facing down-stream in flow direction 30, i.e. facing towards the valve chamber 10. By this, the obstruction 32 can deflect a fluid flow entering in a direction opposite to the flow direction 30 and/or block such fluid flow. By this, it is prevented that the fluid flows further upstream against the usual flow direction 30, so that an influence on the temperature in the area, in which the temperature sensor 38 is located, can be reduced or eliminated.

[0039] Concerning the size and position of the obstruction 32 there are some preferred parameters. For example the distance d between the inner free end of the obstruction 32 and the outer circumference of the ball-shaped valve element 2 should be larger than zero and smaller than the inner diameter D of the second inlet port 6 adjacent to the valve chamber 10. The angle A between the obstruction 32 and the inner circumferential wall 36 of the second inlet port 6, i.e. the angle A between the obstruction 32 and the longitudinal axis X should preferably be in a range between 15° and 90°. The angle A is the angle between a surface on the downstream side of the obstruction 32, seen in usual flow direction, and the inner circumferential wall 36 of the second inlet port 6 adjacent to the valve chamber 10. The radial extension r of the obstruction 32 is preferably larger than three percent of the diameter D and smaller than 25 percent of the diameter D described above. The radial extension r is the radial distance of the inner free end of the obstruction 32 from the inner circumferential wall 36 of the second inlet port 6 adjacent to the valve chamber 10. The obstruction 32 extends from the inner circumferential wall 36 into the interior of the second inlet port 6 by the radial extension r. At the same time the obstruction 32 is angled or extends obliquely to the inner circumferential wall 36 by the angle A to form the pocket-like area or space 34.

[0040] Beside this general preferred structure of the obstruction 32 there are several possibilities to arrange or provide such an obstruction 32 inside the second inlet port 6. As shown in the example in FIG. 1 the obstruction 32 is provided on an insert 38 inserted into the second inlet port 6 and at the same time forming a valve seat for the valve element 12. Furthermore, in this design the obstruction 32 has the shape of a ring-shaped lip extending into the interior of the second inlet port 6. FIG. 3 shows a similar embodiment with an insert 38′. In this embodiment the valve seat is enlarged so that also the valve seat 40 comprises a portion extending into the interior of the second inlet port 6.

[0041] In the embodiment according to FIG. 4 the obstruction 32 is integrally formed with the valve housing 2, i.e. with the portion of the valve housing 2 defining the second inlet port 6. In this embodiment only the valve seat 40′ is formed as an insert.

[0042] Also in the further embodiment shown in FIG. 5 the obstruction 32 is integrally formed with the portion of the valve housing 2 defining the second inlet port 6. However, in this embodiment the obstruction 32 is not lip-shaped but has a shape of a shoulder defining the pocket-like area 34. In longitudinal direction, i.e. in direction of the longitudinal axis X the obstruction 32 forms a reduction in diameter inside the second inlet port 6 extending in upstream direction. Further upstream the diameter is enlarged.

[0043] Also in the embodiment according to FIG. 6 the obstruction 32 is formed on an insert 42. However, in this embodiment the insert 42 defining the obstruction 32 is independent from the insert 40′ defining the valve seat.

[0044] It has to be understood that all the dimensions explained with reference to FIG. 1 could be used in the same way for the embodiments shown in FIGS. 3 to 6. Furthermore, other possibilities to arrange an obstruction 32 on the inner circumference of the second inlet port 6 can be used to achieve similar effects.

[0045] While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

TABLE-US-00001 Reference characters 2 valve housing 4 first inlet port 6 second inlet port 8 outlet port 10 valve chamber 12 valve element 14 opening 16 drive motor 18 mixing valve 20 heat source 22 heating circuit 24 circulator pump 26 return line 28 temperature sensor 30 flow direction 32 obstruction 34 pocket-like area 36 inner circumferential wall 38, 38′ insert 40, 40′ valve seat, insert forming valve seat 42 insert R rotational axis x, y longitudinal directions d distance D diameter A angle r radial extension