Diaphragm valve housing

Abstract

Diaphragm valve housing, with at least two axially extending fluid channels (10, 12) which are aligned with and converge towards each other, a partition (38) between the fluid channels (10, 12) which has a free end directed towards a lateral valve chamber (32) and with its free end forms a valve seat (26) which lies between adjacent openings (28, 30) of the fluid channels (10, 12), wherein the fluid channels (10, 12) each have a cylindrical axial section (34, 36) and a channel end section (40, 42) adjoining it, which extends laterally and obliquely towards each other relative to the axial direction (A) of the axial sections (34, 36), towards the valve chamber (32), and which are separated by the partition (38), wherein the partition (38) in axial longitudinal section view serves to delimit the fluid channels (10, 12) a side section inclined to the axial direction (A), linear in axial longitudinal section view (44,46) on both sides of the valve seat (26), wherein the two linear side sections (44, 46) transition into the valve seat in a curved transition section (100), characterized in that each transition section (100) has, starting from the linear side section (44, 46) in axial longitudinal section view, a first section (102) with a curvature (K1) and subsequently a second section (104) with a lesser curvature (K2), which forms the longest part of the transition section (100).

Description

[0001] The invention relates to a diaphragm valve housing with at least two axially extending fluid channels that are aligned with and converge towards each other, a partition between the fluid channels which has a free end directed towards a lateral valve chamber and with its free end forms a valve seat located between adjacent openings of the fluid channels, wherein each fluid channel has a cylindrical axial section and an adjoining channel end section extending laterally and obliquely towards each other relative to the axial direction of the axial sections, towards the valve chamber, which are separated by the partition, wherein the partition, viewed in axial longitudinal section, has a side section on both sides of the valve that is oblique to the axial direction and linear in longitudinal section view to limit the fluid channels.the two linear side sections transition into the valve seat via a curved transition section.

[0002] Such a diaphragm valve is known from DE 10 2013 101 497 A1. In this diaphragm valve, the partition is designed with optimized manufacturing properties; in longitudinal section, it comprises linear side surfaces that converge towards the valve seat, resulting in a trapezoidal cross-section.

[0003] DE 10 2004 001 045 A1 discloses a diaphragm valve housing with a partition between the valve channels, the course of which, viewed in longitudinal section, is a 5th-degree polynomial or a sinusoid. This design is intended to reduce pressure losses and / or increase the flow rate.

[0004] In general, "axial longitudinal section view" means that the section axis runs through the longitudinal axis of the cylindrical sections.

[0005] Diaphragm valve bodies have inlet and outlet connections that lead into fluid channels. These two aligned fluid channels, sharing a common axial axis, are typically defined by pipe sections. Shortly before the partition, the channels bend laterally and converge to open into the common valve chamber. This chamber is then closed by a diaphragm against the valve body. The diaphragm is clamped between the valve body and an actuator housing flanged to it. The actuator housing contains actuators with plungers and / or pistons that press the diaphragm against the valve seat or allow it to be lifted from the valve seat, thus connecting or separating the channels.

[0006] The object of the invention is, on the one hand, to make the manufacturability of the partition wall as simple as is the case in DE 10 2013 101 497 A1, and on the other hand, to optimize the sealing effect on the seat surface.

[0007] In a diaphragm valve of the type mentioned above, this is achieved by having each transition section, starting from the linear side section in axial longitudinal section, have a first section with a large curvature and then a second section with a smaller curvature, which forms the longest part of the transition section in longitudinal section view. Tests have shown that a perfect compromise is to have a large curvature first, followed by a small curvature, before reaching the valve seat. If only a large curvature were provided, the axial width of the valve seat would be reduced. Increasing the axial width results in a larger sealing surface, which in turn ensures a better seal.Conversely, if the transition section were designed with only a single, very small radius of curvature, the result would be a wide valve seat but an angular transition to the valve seat that would be very difficult to produce smoothly. This would necessitate manual post-processing by polishing, significantly increasing the manufacturing costs of the diaphragm valve housing. The terms "large" and "small" are used solely to clarify the distinguishability of the curvatures and indicate that the curvature of the first section is greater than that of the second.

[0008] The transition section can have a third section that connects directly to both the second section and the valve seat, effectively forming the link between the second section and the valve seat. This curved third section eliminates the need for a sharp edge at this point. Such an edge can have negative effects on fluid flow. However, minor edges can be tolerated as an alternative.

[0009] The first, second, and / or third section can each be formed by a single radius. This simplifies the design and manufacturability.

[0010] A particular embodiment results from the fact that the theoretical circle of the radius of the second section, in an axial sectional view, does not transition tangentially into the valve seat and / or the side section, but rather intersects them. In the prior art, a radius was always used as the transition point that transitioned tangentially into both the side section and the valve seat. Figuratively speaking, the theoretical circle of the radius of the second section is, so to speak, moved further outwards, away from the partition, so that the circle lies partially above the valve seat or to the side of the partition. This circle theoretically intersects the line through the valve seat and / or the side section. By shifting the circle partially outside the partition, the wall thickness of the partition near the valve seat and the width of the valve seat, measured in the axial direction, are increased. This, in turn, improves the sealing.

[0011] For easier manufacturing, the first and third sections can be formed by the same radius.

[0012] The dimensions of the transition section should differ significantly between the radius of the second section and that of the first section to fully exploit their respective advantages. The radius of the second section should be at least 5 times, and ideally at least 8 times, larger than that of the first section.

[0013] The two side sections, which are linear in cross-section, form an angle ranging from 50° to 70°. Smaller angles reduce the load-bearing capacity of the partition and result in poorer fluid deflection. Larger angles improve fluid deflection but increase the axial installation space due to the thickened partition at its base.

[0014] The side sections are each either a cylindrical or a flat surface. In particular, the side sections are mirror-symmetrical about a radial plane in the axial direction that passes through the axial center of the valve seat.

[0015] Manufacturing in the area of ​​the base of the partition is facilitated if the side sections each terminate at their end furthest from the valve seat on a steep section that takes a larger angle to the axial direction than the second section.

[0016] This steeper section forms the transition to the adjacent axial section of the fluid channel.

[0017] A lateral annular flange for attaching a diaphragm can also be integrally formed on the diaphragm valve housing, with the valve seat connecting opposing sections of the annular flange. Viewed from above, the fluid channels can have a semicircular opening.

[0018] Preferably, the diaphragm valve housing according to the invention is exclusively machined, without hand polishing in the area of ​​the partition.

[0019] A valve housing blank for manufacturing a diaphragm valve housing according to the invention can be produced in various ways. For example, the blank can be a forged stainless steel blank or a cast blank. The process offers such significant cost savings that the blank can also be a solid block or cuboid from which the housing is machined "from a solid piece." Such a process still offers cost advantages compared to previous methods.

[0020] One aspect of the invention provides that the axial sections are produced first, followed by the side sections. When milling the side sections, the milling cutter is inserted to such a depth that the channel end sections are already connected to the axial sections. This means that the so-called offset milling can potentially be completely eliminated, or at least minimized.

[0021] After creating the inclined section, the steeper section(s) should be removed or milled away, or the steeper section can be rotated during the creation of the axial sections. In this case, the end face resulting from the rotation forms the steeper section, which thus runs radially to the axial direction of the axial section of the corresponding channel. This radial surface can also be chamfered in the transition area to the side section.

[0022] Further features and advantages of the invention will become apparent from the following description and from the following drawings, to which reference is made. The drawings show: - Fig. 1 a top view of a valve housing blank from which the diaphragm valve housing according to the invention is manufactured, - Fig. 2 a perspective view of the valve housing blank after Fig. 1, - Fig. 3 a longitudinal section view through the valve housing blank after Fig. 1, - Fig. 4. the valve housing blank Fig. 1 when milling fluid channels in perspective view, - Fig. 5 Another perspective view of the valve housing blank during milling, - Fig. 6 a top view of a first embodiment of the diaphragm valve housing according to the invention, - Fig. 7 a longitudinal section view through the diaphragm valve housing Fig. 6, - Fig. 8 a longitudinal sectional view through a second embodiment of a diaphragm valve housing according to the invention, - Fig. 9 a top view of the diaphragm valve housing according to Fig. 8, - Fig. 10 a radial section view through the diaphragm valve housing along line XX in Fig. 9, - Fig. 11 a greatly enlarged detail view through the partition wall of the diaphragm valve housing according to the invention in the transition section from the valve seat to a side section in axial longitudinal section view, and - Fig. 12a and Fig. 12b Variants of the in Fig. 11 shown transition section.

[0023] In the Fig. 6 and Fig. Figure 7 shows a first embodiment of a diaphragm valve housing, which is made from a one-piece valve housing blank, for example as described in the Fig. The product shown in 1 to 3 is manufactured.

[0024] The diaphragm valve housing has two axially extending fluid channels 10, 12 along a common central axis A, extending towards each other and aligned accordingly. These fluid channels 10, 12 extend partially into the nozzle-like, tubular ends 14, 16, at which the diaphragm valve housing is connected to fluid lines.

[0025] In addition to the nozzle-shaped ends 14, 16, the diaphragm valve housing has a lateral annular flange 18 formed, which is preferably flat, extends parallel to the axis A and against which a diaphragm 20 is pressed (see Fig. 7).

[0026] The diaphragm 20 is pressed between the diaphragm valve housing and an actuator housing 22, in which a pressure piece 24, axially movable by an actuator, is radially mounted. The actuator for the pressure piece 24 can be a magnetic, hydraulic, pneumatic, or other type of actuator. The pressure piece 24 rests against the rear of the diaphragm 20 and can press it against a valve seat 26 in the diaphragm valve housing to separate the two fluid channels 10 and 12 from each other.

[0027] The fluid channels 10 and 12 each have an outlet opening 28 and 30, respectively, in the region of the ring flange 18, through which the fluid channels 10 and 12 open into a common valve chamber 32, which is formed above the valve seat 26 when the diaphragm 20 is lifted. The fluid channels 10 and 12 are optionally interconnected via the valve chamber 32.

[0028] The fluid channels 10, 12 therefore have, with reference to Fig. 7, each a circular cylindrical axial section 34 or 36, wherein this section is the section of the fluid channels 10, 12 in which these run axially and are aligned with each other. The two axial sections 34, 36 terminate at a partition 38, which is an integral part of the valve housing. The partition 38 then defines, section by section, the channel end sections 40 and 42 that adjoin the axial sections 34, 36. These channel end sections form the transition from the axial sections 34, 36 to the outlet openings 28 and 30, respectively, and run obliquely towards each other and towards the valve chamber 32 in the axial direction. The respective channel end sections 40, 42 are thus bounded section by section by the partition wall 38 and otherwise by side walls, which are partly formed in the stub-shaped ends 14, 16 and partly at the ring flange 18.

[0029] In Fig. Figure 6 shows that the openings 28, 30 are kidney-shaped or, in the broadest sense, semicircular or segment-shaped, and that the two flat sides face each other. The valve seat 26 extends between the flat sides of the two kidney-shaped openings 28, 30, forming the upper surface of the web-like partition 38 facing the valve chamber 32. This valve seat 26 lies slightly lower than the upper surface of the annular flange 18 and can also have a slight arc shape in the axial direction, that is, it extends from the flange surface towards its center below the plane of the annular flange 18 and then rises again towards the plane of the annular flange 18.

[0030] The partition wall 38, with its free end towards the valve chamber 32, forms the valve seat, so to speak.

[0031] In Fig. Figure 7 shows that the partition 38 has several sections to delimit the two fluid channels 10, 12. Starting from the valve seat 26, the partition 38 forms a side section 44, 46 close to the valve seat 26, which is flatter in the axial direction, i.e., towards axis A, and a subsequent steeper section 48, 50. The flatter side sections 44, 46 give the partition 38 a trapezoidal shape in this area (see Figure 7). Fig. 7) A transition section 100 forms the transition from the valve seat 26 to the respective adjacent side section 44, 46.

[0032] In the embodiment according to the Fig. 6 and Fig. 7. The flatter side sections 44, 46 are each formed by a flat surface, which is also in Fig. 6 can be seen. However, this should not be understood as a limitation.

[0033] In this embodiment, the steeper sections 48, 50 are designed as surfaces that run perpendicular to the plane of the ring flange 18, and section by section, preferably in the area where they adjoin the side sections 44, 46, as planar radial surfaces, that is, as surface sections that lie perpendicular to the axis A.

[0034] In Fig. Figure 7 shows that the steep sections 48, 50 then transition into the respective cylinder wall in a small radius, which limits the axial sections 34, 36.

[0035] The flat side sections 44, 46 end on both lateral directions, see Fig. 6, in arc-shaped sections 52, 54.

[0036] Viewed from the valve seat 26 along the side sections 44, 46, the bend between the side sections 44, 46 and the steeper sections 48, 50 results in an undercut which bears the reference numerals 56, 58.

[0037] If fluid flows from fluid channel 10 into fluid channel 12, turbulence forms in the undercut 58, which would carry away any particles possibly carried in the fluid from the undercut 58.

[0038] The side sections 44, 46 and, in the present embodiment, also the steep sections 48, 50 are each formed by straight segments in longitudinal section view.

[0039] In the illustrated embodiment, the arc-shaped sections 52, 54 transition into the steep section 48, 50, specifically into a top view (see Fig. 6) cylindrical segment-shaped section 60 of the steeper section 48, 50 above.

[0040] The method for manufacturing the diaphragm valve housing according to the Fig. 6 and Fig. 7 will be discussed below using the following examples: Fig. 1 to 5 explained. The blank already forms recesses 62, 64 as well as a base for the partition wall.

[0041] Preferably, the stub-shaped ends 14, 16 are first machined externally and internally, preferably by turning, so that the two cylindrical axial sections 34, 36 are produced first. During this turning, the workpiece is cut so deeply that the end face of the resulting opening already forms the steeper section 48, 50.

[0042] Subsequently, the channel end sections 40 and 42 are produced by milling, as shown in the Fig. 4 and Fig. 5 can be seen. The milling cutter bears the reference number 70.

[0043] The milling cutter 70 is positioned at an angle to the plane of the ring flange 18 and, in this embodiment, does not need to produce the corresponding opening by countersinking, but preferably entirely by hobbing. The preferably flat side sections 44, 46, in particular, can be produced very quickly.

[0044] Finger milling cutters with a cylindrical outer contour can be used here, although a slightly conical outer contour is also possible. The cutter tip can optionally also have a spherical shape.

[0045] In Fig. 5 is only a part of the corresponding channel end section 40 that is outlined with a thick line, whereas the channel end section 42 has already been milled.

[0046] The surface can then optionally be sanded, although in the embodiment shown this can only be done by machine.

[0047] The embodiment according to the Fig. Sections 8 to 10 correspond to the previous embodiment except for the design of the steeper section 48, 50, so only the differences need to be discussed below. The corresponding sections, parts, or surfaces retain their reference numerals; full reference can be made to the previous description.

[0048] In the embodiment according to the Fig. 8 to 10, the respective steeper section 48, 50 is identical in its basic form to the embodiment according to the Fig. 6 and Fig. 7, however, the edge is 80 (see Fig. 8, arrow with reference numeral 80) in the area of ​​the transition from the side section 44, 46 to the section 48, 50 running perpendicular to the plane of the ring flange 18, is milled section by section, i.e. chamfered. In Fig. Figure 9 shows that the arc-shaped milling creates additional surfaces 82, 84 in the steeper section. These sections 82, 84 are also oriented at a steeper angle to the axial direction A than the corresponding side sections 44, 46.

[0049] How Fig. As can also be seen from Figure 9, the milled, arc-shaped steep sections 82, 84 are only present in the area of ​​the flat areas of the side section 44, 46, i.e. following it, so that the arc-shaped sections 52, 54, as in the previous embodiment, transition directly into the arc-shaped sections 60 of the steeper sections running perpendicular to the plane of the ring flange 18.

[0050] The diaphragm valve housing is manufactured as in the previously described embodiment. The only difference is that at the end of the manufacturing process for producing the channel end sections 40, 42, the edge 80 on both channel end sections 40, 42 is milled off section by section by tilting the milling cutter.

[0051] It should be emphasized that, of course, the production of the cylindrical axial sections 34, 36 can also take place at the end of the production process in both embodiments, so that the channel end sections 40, 42 are produced at the beginning.

[0052] Furthermore, the diaphragm valve housing can also be manufactured from a cast blank or a forged stainless steel blank.

[0053] The flatter side sections 44, 46 can also be designed as cylindrical surface sections or conical sections (e.g. of an oblique cone).

[0054] In the Fig. 11 and Fig. 12a and Fig. 12b shows options for the design of the transition sections 100, which connect the linear side sections 44, 46 with the valve seat 26 (see Fig. 7 and Fig. 8) connect. It should be emphasized that for all embodiments the partitions 38 according to the Fig. 7 and Fig. 8 are designed to be mirror-symmetrical about a radial plane through the center of the partition 38. Thus, the transition section 100 between the side section 44 and the valve seat 26 is identical to the transition section 100 between the side section 46 and the valve seat 26, only mirrored.

[0055] The transition section according to Fig. 11 comprises, starting from the side section 46 in the direction of the valve seat 26, a first section 102 with a curvature K1, which is relatively large, then a second section 104 with a curvature K2, which is significantly smaller than the curvature K1, and, optionally, a third section 106 with a curvature K3, which preferably corresponds to the curvature K1. In the sectional view according to the Fig. 11 and Fig. 12a and Fig. Figure 12b shows that the second section is significantly longer than the first and third sections.

[0056] The curvatures K1 to K3 are preferably defined in axial longitudinal section view by a radius, wherein the radius of the second section 104 is at least a factor of 5, preferably at least a factor of 8, greater than the radius of the first section 102.

[0057] In Fig. Figure 11 also shows the theoretical circle 108 of the radius of curvature K2, represented by dashed lines. It can be seen that this circle does not merge tangentially into the valve seat 26, but rather intersects the line through the valve seat 26 in the region of the third section 106. Similarly, the circle 108 intersects the line through the side section 46 and does not merge tangentially into it. The point of intersection lies in the region of the first section 102.

[0058] In the embodiment according to Fig. In section 12a, the theoretical circle 108 intersects the side section 46 and the line along the side section 46, but transitions tangentially into the valve seat 26. However, a large curvature K1 with a small radius (indicated by a small circle) is still provided in the first section 102 as a transition between the side section 46 and the second section 104 with a small curvature. Here too, the second section 104 is defined by the circle 108.

[0059] In the embodiment according to Fig. In section 12b, the second section 104 transitions tangentially into the valve seat 26. The first section 102 is again defined by a small radius (indicated by a small circle). The second section 104 has a significantly smaller curvature than the first section 102, but not just one curvature, rather several: a first concave curvature, indicated by circle 108, and a subsequent convex curvature, where the transition to the valve seat 26 is tangential. This second curvature, which is convex, is also defined by a radius. Here too, circle 108 intersects the line defined by side section 46 in axial longitudinal section view and does not transition tangentially into it.

[0060] In Fig. Figure 11 clearly shows that by shifting circle 108 upwards and to the right (relative to the plane of the drawing), i.e., away from partition 38, more material remains at the top of the partition, i.e., closer to the valve seat 26, than in a transition section formed only by circle 108, where circle 108 transitions tangentially into both side section 46 and valve seat 26. The same applies to the Fig. 12a and Fig.12b. The theoretical linear extensions of the valve seat 26 and the side section 46, represented by dashed lines 110, also show that without the curved transition section 100, the flow would be obstructed by a separation edge, and that this angular section is relatively difficult to machine in such a way that all surfaces should be as smooth as possible and a predefined transition between the surfaces of the side section 44, 46 and the valve seat 26, which must be adhered to within narrow limits, must be maintained. This would not be the case if this edge had to be machined manually.

Claims

[1] Diaphragm valve housing, with at least two axially extending fluid channels (10, 12) which are aligned with one another and run towards one another, a partition wall (38) between the fluid channels (10, 12), which has a free end directed towards a lateral valve chamber (32) and forms with its free end a valve seat (26) which is located between adjacent mouth openings (28, 30) of the fluid channels (10, 12), wherein the fluid channels (10, 12) each have a cylindrical axial section (34, 36) and an adjoining channel end section (40, 42) which runs laterally and obliquely towards one another with respect to the axial direction (A) of the axial sections (34, 36) towards the valve chamber (32), which are separated by the partition wall (38), wherein the partition wall (38) seen in an axial longitudinal sectional view serves to delimit the fluid channels (10, 12) each have a side section (44,46) on both sides of the valve seat (26), wherein the two linear side sections (44, 46) merge into the valve seat in a curved transition section (100), , characterized by that each transition section (100) starting from the linear side section (44, 46) has, in axial longitudinal section view, a first section (102) with a curvature (K1) and then a second section (104) with a smaller curvature (K2), which forms the longest part of the transition section (100). [2] Diaphragm valve housing according to claim 1, characterized by that the transition section (100) has a third section (106) which directly adjoins both the second section (104) and the valve seat (26). [3] Diaphragm valve housing according to claim 1, characterized by that at least the first and / or the second section (102, 104) is each formed by a radius, or according to claim 2, characterized bythat at least the first, the second and / or the third section (102, 104, 106) is each formed by a radius. [4] Diaphragm valve housing according to claim 3, characterized by that the theoretical circle (108) of the radius of the second section (104) does not merge tangentially into the valve seat (26) and / or the side section (44, 46) in an axial sectional view, but rather, seen in an axial longitudinal sectional view, intersects a straight line through the valve seat (26) or the side section (44, 46). [5] Diaphragm valve housing according to claim 2 or one of claims 3 and 4, if dependent on claim 2, characterized by that the first and third sections (102, 106) are formed by a radius and the radius of the first and third sections (102, 106) is the same. [6] Diaphragm valve housing according to one of the preceding claims, characterized bythat the radius of the second section (104) is at least a factor of 5, in particular at least a factor of 8, larger than that of the first section (102). [7] Diaphragm valve housing according to one of the preceding claims, characterized by that the two side sections (44, 46) enclose an angle in a range of 50 to 70° with each other. [8] Diaphragm valve housing according to one of the preceding claims, characterized by that the side sections (44, 46) are each a cylindrical, conical or flat surface. [9] Diaphragm valve housing according to one of the preceding claims, characterized by that the valve seat (26) runs linearly and parallel to the axial direction in an axial longitudinal section view. [10] Diaphragm valve housing according to one of the preceding claims, characterized bythat the side sections (44, 46) each end at their end remote from the valve seat (26) at a steep section which forms a larger angle to the axial direction than the side section (44, 46). [11] Diaphragm valve housing according to claim 10, characterized by that the steeper section (48, 50, 82, 84) forms the transition to an adjacent axial section (34, 36) of the fluid channel (10, 12). [12] Diaphragm valve housing according to one of the preceding claims, characterized by that a lateral annular flange (18) for attaching a diaphragm is formed on the diaphragm valve housing, wherein the valve seat (26) connects opposite sections of the annular flange (18) to one another. [13] Diaphragm valve housing according to claim 12, characterized by that, when viewed from above onto the annular flange (18), the fluid channels have a semicircular opening (28, 30).

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