diaphragm valve

Abstract

The invention relates to a diaphragm valve (1) for controlling a fluid medium, comprising a solenoid armature (10) which is arranged to be longitudinally movable in an interior space (31) of a pole tube (30) which is closed by a diaphragm (20) and which is connected with the diaphragm (20) in such a way that the diaphragm (20) is configured to be transferred by a longitudinal displacement of the solenoid armature (10) between a closed position in which the solenoid armature (10) pushes the diaphragm (20) onto a sealing seat (41) and closes a fluid passage (42), in particular a fluid inlet (43), and an open position in which the solenoid armature (10) lifts the diaphragm (20) from the sealing seat (41) and opens the fluid passage (42), in particular the fluid inlet (43). The invention is characterized in that the interior space (31) of the pole tube (30) contains a fluid (32) which represents a fluid volume and a gas (33) which represents a gas volume, wherein the fluid volume is greater than the gas volume.

Description

Technical Field

[0001] According to the preamble of claim 1, the present invention relates to a diaphragm valve, specifically a diaphragm valve for controlling a fluid medium. This type of diaphragm valve is known in practice. Background Technology

[0002] Known diaphragm valves include a solenoid armature arranged longitudinally movable within the internal space of an electrode. This internal space is closed by a diaphragm that structurally and sealingly separates the electrode's internal space from a valve chamber or flow chamber. The solenoid armature is connected to the diaphragm such that longitudinal displacement of the solenoid armature allows the diaphragm to move from a closed position to an open position. In the closed position, the solenoid armature pushes the diaphragm against a sealing seat, thereby closing the fluid passage, specifically the fluid inlet. In the open position, the solenoid armature lifts the diaphragm from the sealing seat, thereby opening the fluid passage, specifically the fluid inlet.

[0003] Typically, the fluid inlet of a diaphragm valve is arranged coaxially with the solenoid armature. Therefore, the central sealing portion of the diaphragm is configured to press well against the sealing seat and reliably close the fluid inlet. Similarly, the fluid outlet, leading to the valve flow chamber, is typically offset relative to the fluid inlet. Fluid at the inlet acts on the diaphragm at a first fluid pressure within the sealing seat region. Fluid at the outlet acts on the diaphragm at a second fluid pressure within the region surrounding the sealing seat. Ambient air is typically sealed within the electrode's internal space, reaching the electrode during assembly at atmospheric pressure.

[0004] In the closed position of the diaphragm valve, a reset element acting on the solenoid armature prevents the diaphragm from lifting off the sealing seat. For example, this reset element could be a compression spring acting on the solenoid armature to ensure the closed position is maintained. The reset force applied by the reset element is designed to be greater than the force exerted on the diaphragm by the first fluid pressure at the fluid inlet. For this, a relatively small reset force is required because the contact area between the fluid and the fluid inlet and the diaphragm is relatively small. However, if the fluid pressure at the fluid outlet is greater than the fluid pressure inside the electrode space, this second fluid pressure acts on a larger area of ​​the diaphragm, generating a larger force that counteracts the reset force of the reset element. Therefore, the relatively low pressure at the fluid outlet may cause the valve to open undesirably. To prevent this, the reset element must be designed to apply a correspondingly higher preload force to the solenoid armature. However, this results in a greater magnetic force required to open the valve, thus increasing the energy consumption for starting the solenoid valve. Summary of the Invention

[0005] In this context, the object of the present invention is to provide a diaphragm valve that can achieve reliable function with low energy consumption. Specifically, the diaphragm valve should reduce its sensitivity to changes in external pressure at the sealing seat, particularly in the fluid outlet region.

[0006] This objective is achieved by a diaphragm valve incorporating the features of claim 1.

[0007] Therefore, the present invention provides a diaphragm valve for controlling a fluid medium, comprising a solenoid armature arranged to move longitudinally within the internal space of an electrode tube closed by a diaphragm and connected to the diaphragm, such that the diaphragm is configured to transfer between a closed position and an open position by longitudinal displacement of the solenoid armature. In the closed position, the solenoid armature pushes the diaphragm against a sealing seat and closes the fluid passage, specifically the fluid inlet. In the open position, the solenoid armature lifts the diaphragm from the sealing seat and opens the fluid passage, specifically the fluid inlet. According to the invention, the internal space of the electrode tube contains a fluid having a fluid volume and a gas having a gas volume, wherein the fluid volume is larger than the gas volume.

[0008] Unlike previously known diaphragm valves (where the internal space of the electrode is filled only with ambient air, i.e., gas), this invention specifies that the internal space of the electrode is primarily filled with fluid. This reduces the gas volume within the internal space. Thus, due to the relatively small deformation of the diaphragm and the resulting change in the volume of the enclosed gas, the pressure inside the electrode can adapt to the pressure in the fluid passage more quickly. This reduces the pressure generated on the diaphragm, thereby reducing the reset force required by the reset element to hold the valve in the closed position, and therefore the force required to open the diaphragm valve is relatively small. This reduces the energy demand of the diaphragm valve. Specifically, it reduces the pressure difference between the fluid pressure at the fluid inlet or outlet and the internal space of the electrode, thereby reducing the effective pressure on the diaphragm and consequently reducing the impact of pressure changes on valve function. Therefore, the diaphragm valve according to the invention is highly effective and relatively unaffected by pressure differentials.

[0009] The insensitivity of the diaphragm valve to differential pressure directly relates to the size of the remaining gas volume in the internal space of the electrode. In this case, the smaller the gas volume, the better. Simultaneously, the gas volume should be suitable for compensating for the volume change during the transition of the diaphragm from the closed position to the open position, and vice versa, as well as the thermal expansion effect of the fluid caused by temperature changes. In this case, it has proven particularly advantageous if the fluid volume and gas volume together form the total volume, wherein the fluid volume accounts for at least 50%, particularly at least 60%, particularly at least 70%, particularly at least 80% of the total volume. In this case, the fluid volume can account for at most 98%, particularly at most 95%, particularly at most 90%, particularly at most 85% of the total volume. The total volume can correspond to the complete free internal space volume of the electrode, i.e., the internal space volume of the electrode minus the volume of components located within the electrode. For example, these components may include a solenoid armature, a reset element, and / or a guiding element, specifically a spring-loaded guiding element for the reset element.

[0010] To ensure the diaphragm valve performs as expected in all operating states and under all operating conditions, it is advantageous if the fluid is a liquid and exhibits low viscosity under all expected operating conditions, specifically at different ambient temperatures. In this sense, the fluid is preferably incompressible. Therefore, the fluid largely fills only the internal space of the electrode, thus preserving a relatively small gas volume and forming the compressible portion.

[0011] In a preferred embodiment of the diaphragm valve according to the invention, the solenoid armature includes a through-channel that fluidly connects the diaphragm-side portion of the internal space to the return spring-side portion of the internal space. For effective operation of the diaphragm valve, it is advantageous to have a uniform pressure within the internal space of the electrode. Since the solenoid armature is arranged longitudinally movable within the electrode, different pressures will occur in the diaphragm-side region and the return spring-side region of the internal space (i.e., the two sides of the solenoid armature) during armature movement. A through-channel is provided to compensate for this pressure difference. In this case, the through-channel is preferably sized to allow fluid and gas to be conducted from one side of the solenoid armature to the other side.

[0012] The solenoid armature can be operably connected to a solenoid coil extending around the electrode. The electrode can essentially be configured as a type of CAN, where, in a conventional CAN motor, the solenoid armature and solenoid coil are separated. Current can be supplied to the solenoid coil to create an electromagnetic field that moves the solenoid armature longitudinally through the internal space of the electrode. Due to the fluid within the electrode's internal space and related effects, the solenoid coil can be relatively small, resulting in less force consumption when opening the diaphragm valve. This not only improves the energy efficiency of diaphragm valve operation but also reduces material consumption and costs associated with the solenoid coil. Specifically, the cost of copper wire can therefore be reduced because the wire thickness or number of windings in the solenoid coil can be chosen to be relatively small.

[0013] In this invention, a return spring is preferably used as the return element. The solenoid armature can be supported on the axial end flange of the electrode tube by a return spring on the opposite side of the diaphragm. The return spring can be specifically configured as a helical compression spring. This makes the design particularly economical and simple. Furthermore, this type of return spring is particularly reliable and can be easily adapted to the expected pressure.

[0014] In a preferred embodiment of the invention, a diaphragm sealably separates the internal space of the electrode from the valve flow chamber. The valve flow chamber is configured to substantially correspond to the valve chamber. Thus, the diaphragm simultaneously seals off the internal space of the electrode. In this case, it is advantageous if the diaphragm is formed of a flexible material, such as plastic, specifically an elastomer. The diaphragm may also be curved, specifically having a cross-sectional profile that is at least partially cap-shaped, so as to accurately follow movement from the open position to the closed position and vice versa.

[0015] In addition, a fluid passage, specifically a fluid inlet, can be provided, entering the valve flow chamber and configured to be closed by a sealing portion of the diaphragm. The diaphragm can preferably present a circular sealing portion, specifically in the central region. The sealing portion is preferably coaxially configured with the fluid inlet, specifically coaxially configured with the solenoid armature and / or pole. In the sealing portion, the diaphragm can have increased wall thickness to ensure a sufficiently reliable seal at the sealing seat.

[0016] The fluid passage, specifically the fluid inlet, preferably opens coaxially into the valve flow chamber. Therefore, the valve flow chamber can also have a geometry including a central longitudinal axis. In this respect, the valve flow chamber can have a rotationally symmetrical shape. The fluid inlet is preferably arranged coaxially in this rotationally symmetrical shape. This ensures a uniform pressure distribution within the valve flow chamber or valve chamber.

[0017] In the diaphragm valve according to the invention, an additional fluid passage, specifically a fluid outlet, can be provided, eccentrically opening into the valve flow chamber. This additional fluid passage can be permanently fluidly connected to the valve flow chamber, regardless of the diaphragm position. In this respect, the additional fluid passage is permanently open. The diaphragm of the diaphragm valve only opens and closes the first fluid passage or fluid inlet. When the fluid inlet is open, fluid can flow from the fluid inlet through the valve flow chamber to the fluid outlet. When the diaphragm is pushed against the sealing seat by the reset force of the reset element, fluid flow is stopped, thereby closing the fluid inlet. The solenoid armature, driven by the solenoid coil, acts in the opposite direction to this reset force, lifting the diaphragm from the sealing seat and releasing the flow path from the fluid inlet through the valve flow chamber to the fluid outlet. Attached Figure Description

[0018] The invention will now be explained in more detail with reference to the accompanying schematic diagrams, based on exemplary embodiments. Wherein: Figure 1 This is a longitudinal cross-sectional view of the diaphragm valve in the closed position according to the present invention; and Figure 2 It is through the open position Figure 1 The diagram shows a longitudinal cross-sectional view of the diaphragm valve. Detailed Implementation

[0019] The accompanying drawings show a diaphragm valve 1, which includes a solenoid armature 10 arranged longitudinally movable within an electrode 30. The solenoid armature 10 is fixedly connected to a diaphragm 20, which encloses the internal space 31 of the electrode 30. In this configuration, the diaphragm 20 separates the internal space 31 from the valve flow chamber 45. In this configuration, the diaphragm 20 provides a tight seal, forming a sealing boundary between the internal space 31 of the electrode 30 and the valve flow chamber 45.

[0020] The electrode 30 is connected to the valve housing 40, in which a valve flow chamber 45 is disposed. Furthermore, the electrode 30 extends into the drive housing 16, which also includes a solenoid coil 15 operatively connected to a solenoid armature 10. When a current 47 is supplied, the solenoid coil 15 generates a magnetic field that causes the solenoid armature 10 to move longitudinally through the internal space 31 of the electrode 20.

[0021] The electrode 30 also includes an end flange 34 in the internal space 31, wherein a reset spring 12, serving as a reset element, is located between the end flange 34 and the solenoid armature 10. In the exemplary embodiment shown, the reset spring 12 is configured as a helical compression spring.

[0022] The return spring 12 is aligned coaxially with the solenoid armature 10. To maintain this alignment, in each case, a spring guide element 13, which is substantially cylindrical in configuration and extends coaxially into the return spring 12, is provided on both the pole 30 and the solenoid armature 10.

[0023] The solenoid armature 10 also includes a through-passage 11 that passes eccentrically through the solenoid armature 10. The through-passage 11 connects the reset element side subspace of the internal space 31 to the diaphragm side subspace of the internal space 31.

[0024] The solenoid armature 10 is connected to the diaphragm 20 by a connecting bolt 14, the bolt 14 being inserted into the diaphragm 20 in a shape-matching manner through a bolt head. Specifically, the diaphragm 20 can be formed by injection molding the bolt head. Alternatively, the bolt head can be vulcanized into the diaphragm 20. The connecting bolt 14 also includes a bolt extension with external threads that screw into internal threads located within the armature 10. In this way, the diaphragm 20 is securely coupled to the solenoid armature 10. Furthermore, the diaphragm 20 is clamped between the pole tube 30 and the valve housing 40. This clamping fastener can also have a shape-matching component, as the diaphragm 20 and its outer edge form an undercut that engages with a corresponding groove in the valve housing 40.

[0025] The diaphragm 20 includes a central sealing portion 21, in Figure 1 The closed position shown is located on the sealing seat 41, thereby closing the fluid passage 42, specifically the fluid inlet 43.

[0026] Fluid passage 42 or fluid inlet 43 extends coaxially through valve housing 40 to solenoid armature 10. In this case, fluid inlet 43 opens into valve flow chamber 45. In addition to fluid inlet 43, another fluid passage 42 is disposed in valve housing, specifically fluid outlet 44. Fluid outlet 44 passes substantially obliquely through valve housing 40 and opens eccentrically into or out of valve flow chamber 45.

[0027] To enable the integration of the diaphragm valve into a fluid flow system, an external seal 46 is provided on the valve housing 40, configured to seal the diaphragm valve 1 relative to the valve block. Therefore, the diaphragm valve 1 can be integrated into the corresponding fluid flow system with a simple and effective sealing method.

[0028] In the prior art, the internal space 31 of the electrode 30 is typically filled with air, especially at atmospheric pressure. This presents a challenge, particularly if the pressure at the fluid outlet 44 is greater than the pressure within the internal space 31. The fluid pressure at the fluid outlet 44 acts on the diaphragm 20 through its relatively large surface area. This is structurally relevant, from... Figure 1 and Figure 2As can be clearly seen, when pressure from fluid inlet 43 impacts a relatively small area of ​​diaphragm 20, pressure from fluid outlet 44 exists throughout the valve flow chamber 45 and thus acts on a larger area of ​​diaphragm 20. Even though the fluid pressure in fluid outlet 44 is relatively low, this results in a relatively large force acting on diaphragm 20, which includes a principal component opposite in direction to the return force of return spring 12. Therefore, the relatively low fluid pressure in fluid outlet 44 can easily cause diaphragm 20 to move, thereby no longer ensuring a seal between diaphragm 20 and sealing seat 41. This is typically compensated for by a correspondingly higher preload of return spring 12. However, the increased preload of return spring 12 requires a correspondingly larger electromagnetic force to move solenoid armature 10 to open diaphragm valve 1, i.e., to lift diaphragm 20 off sealing seat 41 against the return force of return spring 12.

[0029] The fluid 32 provided by this invention eliminates this problem. Specifically, in the diaphragm valve 1 according to the invention, the internal space 31 of the electrode 30 is mainly filled with fluid 32. In addition, gas 33 is also disposed in the internal space 31 of the electrode 30. A decisive aspect of the function or efficiency of the invention is that the fluid volume of fluid 32 is greater than the gas volume of gas 33 in the internal space 31 of the electrode 30.

[0030] When the solenoid armature 10 moves against the return force of the return spring 12, the total volume of the internal space 31 of the electrode 30 decreases. However, since the fluid is almost incompressible or not incompressible at all, the gas 33 contained in the internal space 31 of the electrode must absorb this volume change. If the gas volume is relatively small, the pressure will increase rapidly, and therefore the pressure in the internal space 31 of the electrode 30 will adapt to the pressure in the valve flow chamber 45 more quickly. Therefore, a smaller return force of the return spring 12 can be selected to move the solenoid armature 10 with relatively less force consumption, thereby improving the overall efficiency of the diaphragm valve 1. In general, the impact of pressure changes on valve function can be significantly reduced. Therefore, the reliability of valve function is increased, especially in the case of pressure fluctuations, which may be caused by changes in ambient temperature and / or the fluid temperature of the fluid medium to be controlled.

[0031] Figure 1 and Figure 2 The operating status of diaphragm valve 1 is displayed. Figure 1The diagram shows diaphragm valve 1 in the closed position. This means that sealing portion 21 supports sealing seat 41 in a sealing manner, thereby closing fluid inlet 43. Solenoid coil 15 is preferably de-energized in this position so that the seal of diaphragm 20 relative to sealing seat 41 is primarily achieved by return spring 12, which pushes solenoid armature 10 toward fluid inlet 43. If the pressure in fluid inlet 43 now increases, return spring 12 will continue to ensure the seal between diaphragm 20 and sealing seat 41 through its preload. For this purpose, a relatively small rebound force is required because the pressure from fluid inlet 43 impacts a relatively small area of ​​diaphragm 20 ( Figure 1 ).

[0032] With the increased pressure in fluid outlet 44, a relatively larger force acts on diaphragm 20 because the pressure in fluid outlet 44 is distributed over a larger area of ​​diaphragm 20, and therefore the force acting on diaphragm 20 is stronger. This hydraulic pressure also pushes solenoid armature 10 against the preload of return spring 12. However, at the same time, the relatively small volume of gas within electrode 30's internal space 31, which is connected to the main fluid 32, ensures that the pressure is distributed within electrode 30, thereby reducing the load on return spring 12. In other words, return spring 12, equipped with a relatively low preload, can still apply sufficient force to seal inlet 43.

[0033] from Figure 1 It can be clearly seen that gas 33 occupies the gas volume formed between fluid 32 and diaphragm 20. As the solenoid armature 10 now moves along the end flange 34 of pole 30, gas 33 is compressed, thus its volume decreases. Since fluid 32 is incompressible, its volume remains essentially constant. Therefore, diaphragm 20 can be lifted from sealing seat 41 to release fluid from fluid inlet 43 through valve flow chamber 45 to fluid outlet 44. Figure 2 Therefore, relatively low force consumption is required, allowing for a smaller size for the solenoid coil 15 and / or the solenoid armature 10. This significantly improves energy efficiency but also enables a more compact design.

[0034] Generally, this applies to all exemplary embodiments, and the fluid 32 used is preferably a liquid under all temperature and other environmental conditions that occur during the operation of the diaphragm valve 1. Furthermore, the fluid 32 should exhibit low viscosity under all possible operating conditions. It is also advantageous if the fluid 32 has a relatively low coefficient of thermal expansion to prevent temperature changes from impairing the operation of the diaphragm valve 1. Additionally, it may be advantageous if the fluid has properties that inhibit corrosion and / or reduce friction. In all cases, it proves particularly advantageous if the fluid 33 is chemically compatible with other materials within the electrode 30.

[0035] List of reference numerals 1 Diaphragm valve 10-Solenoid Armature 11 Through-passage 12 return springs 13 Spring Guide Element 14 connecting bolts 15 Solenoid Coil 16 drive housing 20 diaphragms 21 Sealing Part 30 diode 31 Interior Space 32 fluids 33 Gases 34-end flange 40 valve housing 41 Sealing seat 42 fluid channels 43 fluid inlet 44 fluid outlet 45 valve flow chamber 46 External Seals

Claims

1. A diaphragm valve (1) for controlling a fluid medium, comprising a solenoid armature (10) arranged longitudinally within an internal space (31) of a pole (30) closed by a diaphragm (20) and connected to the diaphragm (20), such that the diaphragm (20) is configured to transfer between a closed position and an open position by longitudinal displacement of the solenoid armature (10), wherein in the closed position the solenoid armature (10) pushes the diaphragm (20) against a sealing seat (41) and closes the fluid passage (42), specifically the fluid inlet (43), and in the open position the solenoid armature (10) lifts the diaphragm (20) from the sealing seat (41) and opens the fluid passage (42), specifically the fluid inlet (43). Its features are, The internal space (31) of the electrode (30) contains a fluid (32) having a fluid volume and a gas (33) having a gas volume, wherein the fluid volume is larger than the gas volume.

2. The diaphragm valve (1) according to claim 1, characterized in that, The fluid volume and the gas volume together form the total volume, wherein the fluid volume accounts for at least 50% of the total volume, specifically at least 60%, specifically at least 70%, specifically at least 80%.

3. The diaphragm valve (1) according to claim 1 or 2, characterized in that, The fluid (32) is substantially incompressible compared to the volume of the gas.

4. The diaphragm valve (1) according to any one of the preceding claims, characterized in that, The solenoid armature (10) includes a through channel (11) that fluidly connects the diaphragm side portion of the internal space (31) to the return spring side portion of the internal space (31).

5. The diaphragm valve (1) according to any one of the preceding claims, characterized in that, The solenoid armature (10) is operatively connected to a solenoid coil (15) extending around the pole (30).

6. The diaphragm valve (1) according to any one of the preceding claims, characterized in that, The solenoid armature (10) is supported on the axial end flange (34) of the pole tube (30) by a return spring (12) on the opposite side of the diaphragm (20).

7. The diaphragm valve (1) according to any one of the preceding claims, characterized in that, The diaphragm (10) seals the internal space (31) of the electrode (30) from the valve flow chamber (45).

8. The diaphragm valve (1) according to claim 7, characterized in that, The fluid passage (42), specifically the fluid inlet (43), opens into the valve flow chamber (45) and is configured to be closed by the sealing portion (21) of the diaphragm (20).

9. The diaphragm valve (1) according to claim 8, characterized in that, The fluid passage (42), specifically the fluid inlet (43), opens coaxially into the valve flow chamber (45).

10. The diaphragm valve (1) according to any one of the preceding claims, characterized in that, Another fluid passage (42), specifically a fluid outlet (44), is eccentrically opened into the valve flow chamber (45).

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