Valve and valve group

Abstract

The invention relates to a valve (100) for a valve group, comprising a valve housing (110) and a fluid channel (120) which is formed in the valve housing (110) and extends between an inlet connection and an outlet connection, in which fluid channel a valve element (140) is received in a linearly movable manner along a movement axis (301) between a first functional position and a second functional position, wherein the valve element (140) is provided with a permanent magnet (144) and is kinematically coupled to a drive mechanism associated with the valve housing (110), and wherein a magnetic field sensor for detecting the position of the valve element (140) is arranged in the valve housing (110), characterized in that a shield plate (150) is arranged on a side surface (112) of the valve housing (110) at the height of the permanent magnet (144), in order to reduce the magnetic flux density provided by the permanent magnet (144) in a spatial region of the outside of the valve housing (110) which adjoins the side surface (112).

Description

Technical Field

[0001] This invention relates to a valve and a valve assembly. Background Technology

[0002] Valves are used to control the flow rate of working fluids, such as compressed air. Each valve has a fluid passage and a valve element movably arranged within the fluid passage, which can locally influence the cross-section of the released fluid passage. In this way, a large amount of working fluid can pass through the fluid passage with a large released fluid passage cross-section, and a small amount of working fluid can pass through the fluid passage with a small released fluid passage cross-section, or no working fluid can pass through the fluid passage with no released fluid passage cross-section. The position of the valve element in the fluid passage provides information about the set released fluid passage cross-section and can be detected by a position sensor. For this purpose, a magnetic field sensor with a permanent magnet assigned to it is provided, for example. Multiple valves can be combined in a valve assembly to centralize the supply and / or control of the working fluid. Summary of the Invention

[0003] The objective of this invention is to improve the accuracy and robustness of sensing and detecting the position of valve elements in a valve assembly.

[0004] This task is accomplished using a valve that has the following characteristics: The valve for a valve assembly according to the invention has a valve housing and a fluid passage constructed in the valve housing extending between an inlet connector and an outlet connector, wherein a valve element is received in the fluid passage in a manner linearly movable along a motion axis between a first functional position and a second functional position, wherein the valve element is provided with a permanent magnet and is kinetically coupled to a drive mechanism assigned to the valve housing, and wherein a magnetic field sensor for detecting the position of the valve element is arranged in the valve housing, wherein a shielding plate is arranged on the side of the valve housing at the height of the permanent magnet in order to reduce the magnetic flux density provided by the permanent magnet in the space region adjacent to the outside and side of the valve housing.

[0005] The valve body is pre-shaped to fit the valve's external form and can be made of plastic. A fluid passage extends within the valve body. Working fluid is conducted through this passage. Working fluid, particularly compressed air, enters the fluid passage through an inlet connector and exits through an outlet connector. More than one inlet connector and more than one outlet connector can be provided. Specifically, a working fluid source is connected to the inlet connector, and a fluid load, such as a pneumatic actuator or pneumatic cylinder, is connected to the outlet connector.

[0006] The valve element is linearly movably received within the fluid passage along its axis of motion. The valve element influences the cross-section of the released fluid passage, that is, it expands and / or contracts the cross-section of the released fluid passage depending on the outlet position. The cross-section of the released fluid passage is related to the amount of working fluid that can be delivered through the fluid passage per unit time. The smaller the cross-section of the released fluid passage, the less working fluid can be delivered through the fluid passage per unit time. If the fluid passage is closed, no more working fluid can be delivered through the fluid passage.

[0007] The valve element is movable between a first functional position and a second functional position. The first and second functional positions differ from each other in the cross-sectional area of ​​the released fluid passage assigned to each individual functional position. For example, the first functional position may have the largest released fluid passage cross-section, while the second functional position may have the fluid passage closed. Furthermore, the valve can be configured to place the valve element in another functional position between the first and second functional positions. Such a valve is called a proportional valve.

[0008] The axis of motion of the valve element can extend parallel to or obliquely to the longitudinal axis of the fluid passage, particularly perpendicular to it. A valve seat can be arranged in the fluid passage, wherein the valve element has a sealing section that seals against or rests on the valve seat in a first functional position. The valve can be configured such that the outer circumferential surface of the sealing section abuts against the valve seat in a second functional position. Such a valve is called a spool valve. Alternatively, the valve can be configured such that the end face of the sealing section rests on the valve seat in the second functional position. Such a valve is called a center valve. A rubber-resilient seal can be fixed to the sealing section. In particular, the sealing section has a groove in which a rubber-resilient sealing ring is received.

[0009] To detect the position of a valve element in the fluid passage, the valve element is equipped with a permanent magnet and arranged within the valve housing of a magnetic field sensor. The magnetic field sensor is configured to output a specific sensor signal based on the magnetic field surrounding it. The permanent magnet influences the magnetic field surrounding the sensor such that the smaller the distance between the permanent magnet and the sensor, the stronger the magnetic field, and vice versa. Because the permanent magnet is coupled to the valve element, the movement of the valve element or its position in the fluid passage affects the strength of the permanent magnet surrounding the sensor. Therefore, the position of the valve element in the fluid passage can be inferred from the strength of the magnetic field surrounding the sensor, as detected by the magnetic field sensor.

[0010] A recess extending into the valve element can be constructed at the first apex of the valve element, which is located externally about the axis of motion, and a permanent magnet can be received in the recess. Alternatively, the permanent magnet can be constructed as a ring arranged on the outer circumferential surface of the valve element.

[0011] The valve element is kinematically coupled to a drive mechanism assigned to the valve housing. Correspondingly, the valve element can be moved by means of the drive mechanism or positioned in different positions within the fluid passage by means of the drive mechanism. The drive mechanism can have an electric, electromagnetic, or pneumatic actuator. In particular, the drive mechanism has a pneumatically operating pre-control valve. The pre-control valve is coupled to a pressure chamber in which a first tip of the valve element is sealed, and the area below this pressure chamber is referred to as a first pressure chamber. If the pre-control valve is manipulated to introduce working fluid, particularly compressed air, into the pressure chamber, the volume in the pressure chamber increases, causing the valve element to move outward, i.e., away from the pressure chamber, along a first direction of motion parallel to the axis of motion.

[0012] To enable the valve element to move in a second direction of motion, extending opposite to the first axis of motion, a second pressure chamber can be provided. This second pressure chamber is fluidly coupled to another pre-control valve if necessary, and a second tip arranged opposite to the first tip is received in a sealed manner within the second pressure chamber. If the valve element is moved in the second direction of motion, pressure is applied to the second pressure chamber by means of the delivery of working fluid, and pressure is reduced in the first pressure chamber if necessary, for example, by venting the first pressure chamber. A single pre-control valve, distributed to both pressure chambers, can be provided instead of two pre-control valves (one of which is assigned to one pressure chamber). This single pre-control valve allows for simultaneous ventilation of the first pressure chamber while venting the second pressure chamber, and vice versa. Such a single pre-control valve can be configured as a 3 / 2 directional valve. Furthermore, a pre-stressed spring coupled to the second tip can be provided instead of or as a supplement to the second pressure chamber, causing the valve element to move in the second direction of motion when no pressure is applied to the first pressure chamber. Furthermore, the valve can be configured as a 5 / 3 directional valve, wherein springs under prestress are respectively provided as a supplement to the first pressure chamber and as a supplement to the second pressure chamber, wherein when no pressure is applied to the two pressure chambers, the two springs under prestress preferably place the valve element in another intermediate position configured as an intermediate position, between the first functional position and the second functional position.

[0013] According to the present invention, a shielding plate is arranged on the side of the valve housing at the height of the permanent magnet. This reduces the magnetic flux density provided by the permanent magnet in the space adjacent to the outer side of the valve housing. This reduction in magnetic flux density in the space adjacent to the outer side of the valve housing reduces the influence of the permanent magnet on the magnetic field sensors of adjacent valves that should also be arranged on the valve assembly. This improves the accuracy and robustness of detecting the position of valve elements in adjacent valves using sensors. This is particularly advantageous when the valves are arranged very closely side-by-side on the valve assembly, for example, with a spacing of only a few millimeters or a fraction of a millimeter relative to each other.

[0014] The reduction in magnetic flux density is achieved by using a shielding plate to redirect the magnetic field lines of the magnetic field provided or induced by the permanent magnet, so that they do not penetrate the shielding plate but extend within it. This prevents the redirected magnetic field lines from entering the valve housing of adjacent valves and affecting their magnetic field sensors. Furthermore, the shielding plate prevents magnetic fields formed outside the valve housing from intruding into it and affecting the magnetic field sensors. These external magnetic fields are particularly those formed by the permanent magnets of adjacent valves.

[0015] The valve housing is oriented with the shielding plates on its sides, particularly perpendicular to the arrangement direction of the valve assembly, along which the valves are arranged. It can be specified that shielding plates are arranged at the height of the permanent magnets on two opposing sides of the valve housing. This ensures that the magnetic field lines induced by the permanent magnets will not enter the valves arranged adjacent to either side, or will not pass through either side to enter the valves.

[0016] Advantageous improvements of the invention are the subject of the dependent claims.

[0017] Preferably, the shielding plate extends beyond the permanent magnet in a first functional position and a second functional position, respectively, along the axis of motion from the inlet connector and from the outlet connector. Considering that the magnetic field is particularly spherically shaped along each spatial direction, the magnetic field exists not only perpendicular to the axis of motion surrounding the permanent magnet in the form of a cylindrical section, but also obliquely along the axis of motion. The magnetic field existing in a horizontal plane opened by the axis of motion and a normal axis extending perpendicularly to the sides, and obliquely but not perpendicular to the axis of motion, is at least partially shielded by the shielding plate extending beyond the permanent magnet as described above. In particular, the shielding plate is configured such that it at least shields the portion of the magnetic field sensor of the adjacent valve that would otherwise affect the magnetic field existing in the horizontal plane and obliquely but not perpendicular to the axis of motion.

[0018] Preferably, the extension of the shielding plate along the axis of motion is at least 20%, preferably at least 50%, and particularly preferably at least 100% larger than the displacement segment swept by the permanent magnet between the first and second functional positions. This displacement segment is generated as the distance between the position of the permanent magnet in the first functional position facing the first outer side of the first functional position and the position of the permanent magnet in the second functional position facing the second functional position and oriented opposite to the first outer side. Correspondingly, this displacement segment is generated as the sum of all the following positions in which the permanent magnet can be positioned. This displacement segment depends on the extension of the permanent magnet along the axis of motion, which is generated by the distance between the first and second outer sides of the permanent magnet, and on the other hand, on the distance between the first and second functional positions. In particular, this displacement segment is generated as the sum of the extension of the permanent magnet along the axis of motion and the distance between the first and second functional positions.

[0019] As an example only, the extension of the shield along the axis of motion is at least 150% greater than the displacement segment swept by the permanent magnet between the first and second functional positions.

[0020] Furthermore, preferably, the extension of the shielding plate along the axis of motion is 500% larger than the displacement segment swept by the permanent magnet between the first functional position and the second functional position, preferably 300% larger and particularly preferably 250% larger.

[0021] Preferably, the extension of the shield along the axis of motion is at least 50%, more preferably at least 100%, and particularly preferably at least 200% greater than the extension of the permanent magnet along the axis of motion.

[0022] Preferably, the shielding plate extends beyond the permanent magnet along a transverse axis that is perpendicular to the axis of motion and parallel to the side, towards the direction of the magnetic field sensor and in a direction away from the direction pointed by the magnetic field sensor.

[0023] Preferably, the extension of the shielding plate along the transverse axis is at least 50%, more preferably at least 100%, and particularly preferably at least 250% greater than the extension of the permanent magnet.

[0024] The magnetic field existing in a vertical plane spanned by the transverse and normal axes and obliquely to the normal line is at least partially shielded by the following method: the shielding plate along the transverse axis is greater than the corresponding extension of the permanent magnet, as previously described. In particular, the shielding plate is configured such that it at least shields the portion of the magnetic field sensor of the adjacent valve that would otherwise affect the magnetic field existing in the vertical plane and obliquely to the normal axis.

[0025] Preferably, the extension of the shielding plate along the transverse axis is 1000% greater than the extension of the permanent magnet, more preferably 800%, and particularly preferably 600%.

[0026] The preferred shielding plate has a higher permeability than the sides. Permeability corresponds to the material's passability to magnetic fields, whereby as permeability increases, the material's passability to magnetic fields also increases, thereby decreasing the resistance to the magnetic field. The direction of the magnetic field is thus affected by the resistance to the magnetic field, causing the magnetic field to extend where the resistance is minimal. Correspondingly, the magnetic field extends in regions with locally highest permeability. Because the shielding plate has a higher permeability than the sides on which it is arranged, the magnetic field induced by the permanent magnet in the lateral regions primarily extends through the shielding plate and does not extend through the sides.

[0027] The shielding plate is preferably made of steel, especially ferritic steel and / or martensitic steel. Steel has high magnetic permeability. Ferritic steel has higher magnetic permeability than martensitic steel. Martensitic steel has higher magnetic permeability than austenitic steel. The shielding plate is preferably made of stainless steel. This provides a shielding plate with high corrosion resistance.

[0028] The preferred magnetic field sensor is a magnetoresistive sensor or a Hall sensor. This allows for the provision of a magnetic field sensor with a small size, thereby enabling the valve housing to be designed to be smaller.

[0029] Preferably, shielding plates are arranged at the height of the permanent magnet on two opposing sides of the valve housing, so as to reduce the magnetic flux density provided by the permanent magnet in the space adjacent to the respective sides on the outside of the valve housing. The scheme mentioned above for a single shielding plate is applied in the same way to each of two individual shielding plates.

[0030] Furthermore, the task is accomplished by a valve assembly having the features described below: The valve assembly according to the invention has a base plate having an air supply passage, an air exhaust passage and a plurality of interfaces, wherein at at least two interfaces a valve configured as described above is fluidly coupled to the valve assembly, and wherein the valves are arranged side by side along an arrangement direction extending particularly perpendicular to the axis of motion such that their sides are oriented substantially parallel to each other. Attached Figure Description

[0031] The invention will now be explained in detail with the aid of the accompanying drawings, in which: Figure 1 Three valves are shown arranged side by side along the arrangement direction; Figure 2 The valve is shown in longitudinal section; and Figure 3 The cross-section is shown in Figure 2 The valve shown in the image. Detailed Implementation

[0032] Figure 1 Three valves 100 are shown arranged side by side along the arrangement direction 305. The valves 100 extend along a motion axis 301 that is perpendicular to the arrangement direction 305, a normal axis 303 that is parallel to the arrangement direction 305, and a transverse axis 302 that is perpendicular to both the motion axis 301 and the normal axis 303.

[0033] Figure 2 The longitudinal section shows the... Figure 1 The valve 100 is shown at the very front. The longitudinal section is from... Figure 1 The cross-section 401 shown is generated. The cross-section 401 is spread apart by the motion axis 301 and the normal axis 303.

[0034] Valve 100 has a valve housing 110. Within the valve housing 110, a fluid passage 120 extends along a motion axis 301 between an inlet connector (not shown) and an outlet connector (not shown). A valve element 140 is received within the fluid passage 120. The valve element 140 is received in a manner that allows linear movement along the motion axis 301 between a first functional position and a second functional position (not shown). Figure 2 In the middle, valve element 140 is in the first functional position.

[0035] As an example only, a stop 114 is constructed in the valve housing 110. In a first functional position, the valve element 140 is spaced apart from the stop 114 by a second tip 149 toward the stop 114. In a second functional position, the valve element 140 rests against the stop 114 with its second tip 149. A lift 180 is created between the first and second functional positions, allowing the valve element 140 to move within the fluid passage 120 by said lift.

[0036] By way of example only, valve 100 has an actuation mechanism (not shown) with a pre-control valve 160. The pre-control valve 160 is arranged on a first tip 148 of valve element 140 away from stop 114. Figure 2 In the first functional position shown, the pre-control valve 160 is controlled such that the valve element 140 does not operate against the spring 162 arranged on the second tip 149 of the valve element 140. If the pre-control valve 160 is manipulated such that the valve element 140 operates against the spring 162 and overcomes the elastic force caused by the spring 162, the valve element 140 is placed in the second functional position.

[0037] The valve element 140 is provided with a permanent magnet 144. By way of example only, a recess 142 extending into the valve element 140 is constructed in the first top end 148, in which the permanent magnet 144 is received.

[0038] A shielding plate 150 is arranged on the side 112 of the valve housing 110 at the height of the permanent magnet 144 to reduce the magnetic flux density provided by the permanent magnet 144 in the space region adjacent to the side 112 outside the valve housing 110.

[0039] As an example only, a valve seat 124 is arranged in the fluid passage 120, wherein the valve element 140 has a sealing section 146 that seals against the valve seat 124 in a first functional position. Figure 2 The valve 100 shown is configured as a slide valve purely by way of example.

[0040] By way of example only, valve element 140 has multiple sealing sections 146 and multiple valve seats 124 arranged in fluid passage 120. For clarity, in Figure 2 Reference numerals are provided for only a single sealing section 146 and a single valve seat 124, respectively. By way of example only, in both the first and second functional positions, several sealing sections 146 abut against the valve seat 124 to which they are assigned. Here, several sealing sections 146 that abut against the valve seat 124 to which they are assigned in the first functional position do not abut against the valve seat 124 to which they are assigned in the second functional position, and conversely, several sealing sections 146 that do not abut against the valve seat 124 to which they are assigned in the first functional position abut against the valve seat 124 to which they are assigned in the second functional position.

[0041] As an example only, valve 110 is configured as a 5 / 2 directional valve, wherein four sealing sections 146 and four valve seats 124 are provided.

[0042] By way of example only, the shielding plate 150 extends beyond the permanent magnet 144 in a first functional position and in a second functional position respectively, along the axis of motion 301 from the direction of the inlet connector and from the direction of the outlet connector, that is, from the direction of the first tip 148 and the second tip 149 respectively.

[0043] As an example only, a rubber-resilient seal 147 is fixed to the sealing section 146. Furthermore, as an example only, the sealing section 146 has a groove (not shown in the figures) in which the seal 147, configured as a rubber-resilient sealing ring, is received.

[0044] Figure 3 The cross-section is shown in Figure 2 Valve 100 is shown in the diagram. The cross-section is from... Figure 2 It is generated in the cross section 402 shown in the figure. The cross section 402 is supported by the transverse axis 302 and the normal axis 303.

[0045] A magnetic field sensor 130 for detecting the position of valve element 140 is arranged in the valve housing 110.

[0046] As an example only, the shielding plate 150 extends beyond the permanent magnet 144 along the transverse axis 302 toward the magnetic field sensor 130 and in a direction away from the magnetic field sensor 130.

[0047] As an example only, valve 100 has a coupling section 170, which allows valve 100 to be coupled to an interface of a valve assembly (not shown).

Claims

1. A valve (100) for a valve assembly, having a valve housing (110) and a fluid passage (120) constructed in the valve housing (110) extending between an inlet and an outlet, wherein a valve element (140) is received in the fluid passage in a manner linearly movable along a motion axis (301) between a first functional position and a second functional position, wherein the valve element (140) is provided with a permanent magnet (144) and is kinetically coupled to a drive mechanism assigned to the valve housing (110), and wherein a magnetic field sensor (130) for detecting the position of the valve element (140) is arranged in the valve housing (110), characterized in that, A shielding plate (150) is arranged on the side (112) of the valve housing (110) at the height of the permanent magnet (144) to reduce the magnetic flux density provided by the permanent magnet (144) in the space region adjacent to the side (112) outside the valve housing (110).

2. The valve (100) according to claim 1, characterized in that, The shielding plate (150) extends beyond the permanent magnet (144) in a first functional position and a second functional position, respectively, along the motion axis (301) from the direction of the inlet connector and from the direction of the outlet connector.

3. The valve (100) according to claim 2, characterized in that, The extension of the shield (150) along the axis of motion (301) is at least 20%, preferably at least 50%, and particularly preferably at least 100% greater than the displacement segment swept by the permanent magnet (144) between the first functional position and the second functional position.

4. The valve (100) according to any one of the preceding claims, characterized in that, The shielding plate (150) extends along a transverse axis perpendicular to the axis of motion (301) and parallel to the side (112) with an extension that is at least 50%, preferably at least 100%, and particularly preferably at least 250% greater than that of the permanent magnet (144).

5. The valve (100) according to any one of the preceding claims, characterized in that, The shielding plate (150) has a higher permeability than the side surface (122).

6. The valve (100) according to any one of the preceding claims, characterized in that, The shielding plate (150) is made of steel, especially ferritic steel and / or martensitic steel.

7. The valve (100) according to any one of the preceding claims, characterized in that, The magnetic field sensor (130) is a magnetoresistive sensor or a Hall sensor.

8. A valve assembly having a base plate having an air supply passage, an air exhaust passage and a plurality of interfaces, wherein at at least two interfaces a valve (100) according to any one of the preceding claims is fluidly coupled to the valve assembly, and wherein the valves (100) are arranged side by side along an arrangement direction (305) extending particularly perpendicular to the axis of motion (301) such that the sides (112) of the valves are oriented substantially parallel to each other in planar respect.

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