EP4689457A1

EP4689457A1 - A normally open valve

Info

Publication number: EP4689457A1
Application number: EP24781393.4A
Authority: EP
Inventors: Joakim SOMMANSSON
Original assignee: Staccato Technologies AB
Current assignee: Staccato Technologies AB
Priority date: 2023-03-30
Filing date: 2024-03-12
Publication date: 2026-02-11
Also published as: SE547572C2; JP2026511641A; MX2025011578A; WO2024205465A1; CN120344790A; SE2350366A1

Abstract

Described is, among other things, a valve (1) comprising a plunger (2), a valve inlet port, and a valve outlet port. The valve has a valve seat (3) comprising an inner sealing edge and an outer sealing edge. The valve seat is adapted to allow for a flow between the valve inlet port and the valve outlet port when the valve is in an open position, via the inner sealing edge and the outer sealing edge, respectively. The flow via the inner sealing edge flows via an inner path. The valve further comprises a pin (4) extending through the valve seat. The pin connects a seal (6) to the plunger.

Description

A Normally Open Valve TECHNICAL FIELD The present disclosure relates to a valve. In particular the present disclosure relates to a valve to be operated in a normally open configuration. BACKGROUND For many applications a normally open valve, i.e., a valve that only closes when the valve is activated, is desired. For example, different safety features rely on that a valve is open even if the valve cannot be activated. Further WO2016/167699 describes a valve that can reduce the required air gap in a valve. There is a constant desire to improve the operation of valves. Hence, there exists a need for an improved valve. SUMMARY It is an object of the present invention to provide an improved valve. This object and/or others are, at least partly, obtained by the valve as set out in the appended claims. As has been realized by the inventor a normally open valve can be advantageous in many applications. At the same time the valve should be robust and efficient. In accordance with one embodiment, a valve comprising a plunger, a valve inlet port, and a valve outlet port is provided. The valve has a valve seat comprising an inner sealing edge and an outer sealing edge forming a sealing area such that a fluid passing over the sealing area pass both over the inner sealing edge and the outer sealing edge. The valve seat is adapted to allow for a flow between the valve inlet port and the valve outlet port when the valve is in an open position, via the inner sealing edge and the outer sealing edge, respectively. The valve further comprises a pin extending through the valve seat and where the pin connects a seal in one end of the pin to the plunger at the other end of the pin, The valve is configured to, when the plunger is activated, move the seal to a sealing position pressing against the inner sealing edge and an outer sealing edge closing the valve. Hereby the activation of the plunger can enable the seal to act on the other side of the valve seat as seen from the side of where the plunger is located, and the seal does to need to be in the side of the valve seat facing the plunger so that other configurations of the valve can be made possible. In particular the valve can be operative to work as a normally open valve. In accordance with one embodiment, the valve is configured so that when the plunger is not activated, the seal is adapted to be in a resting position distanced apart from the inner sealing edge and the outer sealing edge. Hereby a normally it is ensured that the valve is open when not activated. In accordance with one embodiment, the pin is provided directly at a top end part to of the plunger. Hereby an efficient connection between the plunger and the pin can be provided. Also, the pin can be hollow to allow for an increased amount of air to exit along the pin towards to plunger. In accordance with another embodiment, the pin can be sealed towards the plunger to prevent air from exiting along the pin towards the plunger. In accordance with one embodiment, the pin is provided with a top end section extending laterally in the transverse direction of the longitudinal extension of the pin extending in the inner path. Hereby the seal can be attached in a secure and robust manner to the pin by letting the seal rest against the top part. In accordance with one embodiment, the inner sealing edge can be round, in particular circular. Also, the outer sealing edge can be round, and in particular circular. Hereby an efficient valve can be implemented. In accordance with one embodiment, the inner sealing edge and the outer sealing edge are located in the same plane. Hereby the seal can be made flat. In accordance with one embodiment, wherein at least two supply channels are provided. Hereby a symmetric and efficient supply can be provided. In accordance with one embodiment, the valve is an electromagnetic valve. Hereby a valve with fast response times and which can close and open fast can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described in more detail by way of non-limiting examples and with reference to the accompanying drawings, in which: - Fig.1 is a cross sectional view of a valve, - Fig.2 is a cross-sectional view in perspective of a valve seat, - Figs.3 and 4 are cross-sectional views of a valve in an open position, and - Figs.5 and 6 are cross-sectional views of a valve in a closed position. DETAILED DESCRIPTION In the below description the valve in which the valve seat is present can be an electromechanical valve (solenoid valve) as exemplified below. However, the principles described herein are not limited to such a valve, but the valve can be used in any type of valve. Further, only the parts of the valve relating to the valve seat are described in detail including the sealing of the valve when opening /closing the valve. Thus, some parts that are normally present in a complete valve are omitted in the below description. In Fig.1 an exemplary valve 1, and in particular the parts of a valve seat arrangement, is depicted in an axial sectional view. The valve 1 comprises a plunger 2. In accordance with one embodiment, when the plunger is activated such by providing a current to a coil if the valve is an electromagnetic valve, the plunger is lifted. When the valve is de-activated, the plunger can return by means of a spring force or the like. The valve also comprises a valve seat 3. The valve seat 3 can be generally of the type described in WO2016/167699. The valve seat 3 typically has a circular cross section in a plane perpendicular to the movement of the plunger 2. The valve seat comprises an area, a sealing area, facing a sealing of the valve. The sealing area is formed (limited) by an inner sealing edge and an outer sealing edge so as to let a fluid passing over the sealing area pass both over the inner sealing edge and the outer sealing edge. The sealing area is located on the side of the valve seat opposite to the side where the plunger is located. The valve 1 can typically have additional parts such as parts used to control the plunger, a housing etc. However, for clarity reasons, such parts are not shown in Fig.1. The valve seat described in WO2016/167699 is adapted to allow for a flow of a working medium between an inlet port and an outlet port when the valve is in an open position. The flow path in the open position is both via the inner sealing edge and the outer sealing edge, respectively. Hence, the flow through the valve exits (or enters) the sealing area of the valve from two different direction, via an inner sealing edge and via an outer sealing edge. This provides for a total perimeter of the sealing area that is increased in comparison with a conventional valve seat having a sealing area with only one perimeter. The increased perimeter can reduce the stroke length required for the plunger operating in the valve, which is advantageous. However, such a valve seat is difficult to operate in a normally open configuration of the valve. In order to benefit from the characteristics of the valve seat described above in a normally open valve configuration, a pin can be arranged to extend through the valve seat 3. Thus, in accordance with the embodiment of Fig.1 The plunger 2 is connected to a pin 4. The pin 4 can be configured to run centrally through the valve seat 3. In accordance with one embodiment, the pin 4 is provided directly on the plunger 2. For example, the pin can be located at a top, end part to of the plunger 2. The pin 4 is passed through the valve seat. In particular the pin can be located in an inner path of the valve seat. The pin 4 can then act on the opposite side of the valve seat 3 compared to a normally closed valve. In other words, one end of the pin is located on the side of the plunger and the other end of the pin is located on the opposite side of the valve seat where the sealing area is located. In another embodiment, not shown, the pin is connected to the plunger via at least one intermediate member. Further, a seal 6 is connected to the pin 4. The seal 6 is arranged at the other end of the pin than where the plunger 2 is provided. In accordance with some embodiments such as shown in Fig.1, the seal 6 is attached directly to the pin 4. However, the seal 6 can also be attached to the pin via some other member. When the plunger 2 is maneuvered (activated), the seal 6 close the gap in the sealing area between an inner sealing edge and an outer sealing edge of the valve seat 3 at the sealing area. Thus, when the plunger 2 is activated, the plunger moves the pin 4 in a direction towards the sealing area thereby moving the seal 6 attached to the pin 4 to a position sealing the sealing area thereby closing the valve 1. The seal 6 can be circular and formed by a material having good sealing properties such as elastomers or polyurethane of different types, HNBR, FKM, PUR etc. Thus, when the plunger 2 is not activated, the seal 6 is adapted to be in a resting position distanced apart from the inner sealing edge and the outer sealing edge. Also, when the plunger 2 is activated, the seal 6 is configured to be in a sealing position pressing against the inner sealing edge and the outer sealing edge. In accordance with some embodiments the pin 4 is provided with a top section 5 at the seal end of the pin 4 extending laterally in the transverse direction of the longitudinal extension of the pin running centrally in the valve seat 3. The seal 6 can then be attached to the top section 5. The top section 5 can be circular and can also extend over the width of the seal 6 in order to make the seal 6 press efficiently against the sealing area when the plunger 2 is activated. The top section 5 can be formed as a separate part attached to the pin 4 or it can be formed as an integral part of the pin 4. The pin 4 can have different designs. In accordance with one embodiment the pin 4 is provided with a sealing 9 at a top end part at the end facing the plunger 2 to prevent air from exiting via the pin 4 towards the plunger 2 when the valve is open. In accordance with another embodiment, the pin 4 can be formed as a pipe with air flowing through the center of the pin towards the plunger 2 when the valve is in an open position. The pin 4 can typically have a circular cross-section, but in some embodiments the pin can have another cross section such as oval or rectangular. In accordance with one embodiment the valve can be an electromagnetic valve. The valve can be adapted to use air as working medium. In other embodiments other working medias can be used such as water, oil and the like. In Fig.2, a cross-sectional view in perspective of an exemplary valve seat 3 that can be used is shown. The arrows show the flow of a fluid when the valve is open. In Fig. 2, there is flow from at least one pressurized inlet port 11. The flow path in the open position flow through a sealing area being in contact with an outlet port 12 via an inner sealing edge 13 and an outer sealing edge 14, respectively. Hence, the flow through the valve exits (or enters) the sealing area of the valve in two different flows, via the inner sealing edge 13 and via an outer sealing edge 14 where the outer sealing edge is located radially outside the inner sealing edge. This provides for a total perimeter of the sealing area that is increased in comparison with a conventional valve seat having a sealing area with only one perimeter. The increased perimeter can reduce the stroke length required for the plunger 2 operating in the valve, which is advantageous. In accordance with one embodiment the sealing area is formed in the top area of a recess 15 formed in the valve seat 3. Advantageously the inner sealing 13 edge is round, in particular circular. Also, the outer sealing edge 14 can in some embodiments also be round, and in particular circular. The sealing inner and outer sealing edges can, but do not have to be, located in the same plane. When the inner and outer edges, delimiting the sealing area are located in the same plane, the seal used to seal the sealing area can be made flat. Thus, as indicated by the arrows in Fig.2, a flow can exit the sealing area over two different sealing edges 13 and 14. One flow is via a first outlet path, here, directing a flow from the valve inlet port 11 to an orifice, here a vertical inner path 16. The inner path 16 is typically centrally located in the valve seat 3. In some embodiments a plurality, at least two, supply channels 17 are provided extending between the valve inlet port 11 and the orifice at the sealing area. For example, four supply channel 17 can be provided. The flow entering the sealing area flows to the outlet port 12 in a flow directly to the outlet port 12 over the outer sealing 14 and also via the inner sealing 13 via the inner path 16 to the outlet port 12 of the valve via at least one outer path 18. In some embodiment some air can also exit the valve along the pin 4. As set out above, the pin can be hollow to allow for air to exit via the pin 4. If nor air is desired to exit along the pin 4, the pin 4 can be sealed to prevent air to exit upwards in Fig 2 via the inner path 16 along the pin 4. As set out above, the valve seat 3 described above can comprise an inner path 16 the inlet (outlet) perimeter of which can form an inner sealing edge 13. By letting the working media (in this example air) flow to the outlet port 12 via an outlet area in the sealing surface of the valve seat that has both an inner and an outer perimeter (inner and outer sealing edges), it will be possible to increase the total perimeter of the outlet area in the sealing surface facing the sealing 6 of the valve. Such an arrangement with an increased perimeter of the outlet area being in contact with the sealing 6 operated via the plunger 2 will improve the working of the valve. Thus, in accordance with embodiments described herein the perimeter of the area at the outlet, the sealing area, adapted to be sealed by the sealing of the valve, here the sealing 6, connected to the plunger 2, is increased. The sealing area delimited by the outer and inner sealing edges can for example be ring-shaped as in the example described above and depicted in Fig.2, but other shapes are possible as long as there is both an inner and outer perimeter of the sealing area. The perimeters can be in the same plane but can also be in different planes. This will depend on the geometry of the sealing provided to seal the inlet of the valve from the outlet of the valve. In this example the sealing 6 is generally flat, and the perimeters, i.e., the sealing edges 13 and 14 in this example, are then located in the same plane. Thus, the contact area between the sealing 6 and the sealing edges 13, 14 can be, but do not have to be, flat. The distance between the sealing edges 13 and 14 and the seal 6 can therefore be smaller compared to a conventional valve. The sufficient cross section can be achieved with a smaller distance. Example for 4mm with inner diameter (d1) = 8,05 mm and outer diameter (d2) = 9 mm: Cross section: ^^^^^^^^ = ((^1²×^)−(^2² ×^)) => 12,72 mm² Margin example 10%: ^_^^^^= ^_^^^^^^^ ×1,1 => 13,992 mm² Cylindric flow in air gap: ^_^^^^=((^1 × ^)+(^2 ^ ^))×^ = > L = ^_^^^^/((^1×^)+(^2 ^ ^)) = 0,2614mm ^^^^^^^^ = Orifice Area in (mm2) ^^^^^ = Cross section area in the radial lift (mm2) L = actual lift height in (mm) The larger the radius on the inner and outer sealing edges are the lower the lift height can be achieved, and lower force/power is needed to move the valve. The same is true for the working stroke of the spring of the plunger which then can be reduced, and with reduced working stroke the force of the spring in active state can also be reduced. In Fig.3, a first cross- sectional view from the side of the valve 1 is shown when the valve 1 is in a passive state. The valve 1 is normally open so when the valve is in a passive state (the plunger is not actuated) the valve is open. In the open state the fluid, in this example air, flows from the pressurized side to the through the valve 1 as illustrated by the arrows in Fig.3. Thus, pressurized air enters the valve from a valve inlet and passes through the inlet channel(s) 17 and over the sealing area. In the sealing area the air flow can flow both over the inner sealing edge 13 and the outer sealing edge 14. The air flow over the outer sealing edge is directed directly to the outlet port 12 of the valve and the air flow over the inner sealing edge flows to the outlet port 12 via the inner path 16 as is shown better in Fig.4. Fig.4 is similar to Fig 3, but rotated 90 degrees, and shows a second cross- sectional view from the side of the valve 1 when the valve is in a passive state. Here outer paths 18 that connects the inner path 16 to the outlet port 12 are shown. In accordance with one embodiment at least two outer paths 18 are provided. Fig.5 shows a first cross- sectional view from the side of the valve 1 when the valve 1 is in an active state. The valve 1 is normally open so when the valve is in an active state (the plunger is actuated) the valve is closed. Thus, the plunger 2 is maneuvered thereby activating the pin 4 to move the seal 6 to close the sealing area formed by the inner sealing edge 13 and the outer sealing edge 14, respectively. In the closed state, the fluid, in this example air, is stopped from flowing from the pressurized side through the valve 1 as illustrated by the arrows in Fig.5. As is seen, the pressure in the closed state will be the same at the outlet port 12 as in the inner channel 16 so there is no pressure difference over the seal 6. This is further illustrated in Fig.6. Fig.6 is similar to Fig 5, but rotated 90 degrees, and shows a second cross- sectional view from the side of the valve 1 when the valve is in an active state, i.e., closed. Here outer paths 18 that connects the inner path 16 to the outlet port 12 are shown. The air pressure in the outer path is also the same as the air pressure at the outlet port, typically ambient air pressure. By providing a valve where a pin extends through an inner path of the valve seat, an efficient implementation of a valve that can operate in a normally open configuration while allowing for the valve seat to have a configuration that allows the flow in the valve seat to pass the sealed section of the valve over both an inner sealing edge and an outer sealing edge whereby the lifting height of the valve can be reduced. Thus, the valve described herein can provide a shorter stroke compared to existing valve types operating as normally open valves, The response time will be improved. Also, a lower kinetic energy will be present that can reduce wear and extend the life time of the valve. It is to be understood that the features from different embodiments can be combined and that no feature of an embodiment is essential unless explicitly so expressed. Hence, the person skilled in the art can select which features and dimensions that are deemed to be advantageous for a particular implementation. The valve and valve seat above are described in an implementation where the valve is an electromagnetic valve being generally cylindrically shaped and with a generally cylindrically shaped valve seat and designed to use air as working medium. The principles as set out herein are however applicable to other types of valves having other general shapes and also to valves using other types of working medium such as liquid working mediums. The shape of the inner and outer sealing edge can have different forms such as oval or even rectangular.

Claims

CLAIMS 1. A valve (1) comprising: - a plunger (2), - a valve inlet port (11) - a valve outlet port (12) - a valve seat (3) comprising an inner sealing edge (13) and an outer sealing edge (14) forming a sealing area such that a fluid passing over the sealing area pass both over the inner sealing edge and the outer sealing edge, and wherein said valve seat (3) is adapted to allow for a flow between the valve inlet port (11) and the valve outlet port (12) when the valve is in an open position, via the inner sealing edge (13) and the outer sealing edge (14), respectively, the valve further comprising - a pin (4) extending through the valve seat and connecting a seal (6) in one end of the pin to the plunger (2) at the other end of the pin, wherein the valve is configured to, when the plunger (2) is activated move the seal (6) to a sealing position pressing against the inner sealing edge (13) and an outer sealing edge (14) closing the valve. 2. The valve according to claim 1, wherein when the plunger (2) is not activated the seal (6) is adapted to be in a resting position distanced apart from the inner sealing edge (13) and the outer sealing edge (14). 3. The valve according to any one of claims 1 - 2, wherein the pin (4) is provided directly at a top end part to of the plunger (2). 4. The valve according to any one of claims 1 - 3, wherein the pin (4) is provided with a top end section (5) extending laterally in the transverse direction of the longitudinal extension of the pin (4). 5. The valve according to any one of claims 1 - 4, wherein the inner sealing edge (13) is round. 6. The valve according to any of claims 1 – 5, wherein the outer sealing edge (14) is round. 8. The valve according to any of claims 1 – 7, wherein the inner sealing edge (13) and the outer sealing edge (14) are located in the same plane. 9. The valve according to any of claims 1 – 8, wherein at least two supply channels (17) are provided. 10. The valve according to any of claims 1 – 9, wherein the pin (4) is hollow. 11. The valve according to any of claims 1 – 10, wherein the pin (4) is provided with a sealing (9).

12. The valve according to any one of claims 1 - 11 wherein the valve is an electromagnetic valve.