Compact electromechanical valve

Abstract

The electromechanical valve (10) comprises a valve mechanism within a housing (20). The valve mechanism includes a core (34) of magnetizable material surrounded by a coil (32) to which an exciting current is supplied, a stack (36) of plates of magnetic material fixed to its first end, and a valve seat (38). The stack of plates (36) is provided in the space between the core (34) and the valve seat (38), and when an exciting current is supplied to the coil (32), the stack of plates (36) is displaced from the valve seat, thereby opening and closing the valve according to the exciting current supplied to the coil (32). The stack of plates provides a return spring force when the stack of plates is attracted by the energized coil. The core (30) is plate-shaped and has a thickness of less than 3 mm.

Description

Technical Field

[0001] The present disclosure generally relates to valves, and more particularly to electromechanical valves. The present disclosure also relates to configurations including such valves.

Background Art

[0002] In some applications, it is desirable to arrange pneumatic valves in high density. One such application is the sorting of articles by air burst. Sorting by air burst is common in applications for sorting grains, seeds, and other fairly light items by quality and / or characteristics, but is not limited thereto. This is generally done for food, recyclable items, manufacturing, and mineral concentration.

[0003] Sorting is performed by identifying items to be placed on an alternative path and separating them from the main flow. Feeding can be done by hoppers, belts, special cavity drums, or other means.

[0004] For example, US2012152810 describes a sorting device for sorting parts by air blast. This sorting device includes an air blast generator having at least one reversibly deflectable diaphragm unit that bounds a working chamber connected to a discharge opening. By the operation of the diaphragm unit, an air blast is discharged from the working chamber through the discharge port.

[0005] It is always desirable to improve the performance and robustness of valves used in various applications such as sorting devices. Accordingly, there is a need for improved valves, particularly valves suitable for sorting applications.

Summary of the Invention

[0006] The object of the present invention is to overcome or at least partially alleviate the drawbacks of existing valves, and to provide an improved valve that can be used, for example, in sorting applications and as a sorting device.

[0007] Another object is to provide a compact valve that can be used in applications where a plurality of valves are stacked to form an assembly. Here, a plurality of valves can be arranged adjacent to each other and detachably coupled to each other. In order to obtain an efficient assembly of the stacked valves, the valves preferably have a flat design when viewed in the stacking direction.

[0008] These objects and / or others are at least partially achieved by the electromechanical valve according to the present invention described in the appended claims.

[0009] According to the present invention, an electromechanical valve is provided. This valve includes a valve mechanism within a housing. The valve mechanism includes a core of magnetizable material surrounded by a coil to which an excitation current is supplied, and a stack of plates of magnetizable material fixed to its first end. The valve mechanism further includes a valve seat. The stack of plates is provided in the space between the core and the valve seat, and opens and closes the valve according to the excitation current supplied to the coil by displacing the stack of plates from the valve seat when an excitation current is supplied to the coil. The stack of plates provides a return spring force when the energized coil attracts the stack of plates, and the core is plate-shaped with a thickness of 3 mm or less. Thereby, the valve can be made very thin as desired for many applications such as sorting applications.

[0010] According to one embodiment, the core has an attraction section facing the stack of plates, and no coil is wound around the attraction section. Thereby, the valve can be made thinner without degrading the performance of the valve. The attraction section can form a protrusion from the flat core. According to some embodiments, the protrusion is a lip offset from the plane of the core. Thereby, a thinner valve can be provided.

[0011] According to some embodiments, the flat core has a rectangular cross-section. The thickness of the core can be less than 1 mm.

[0012] According to one embodiment, the valve sheet has a slit-shaped sheet opening. Thereby, the performance of the valve can be improved and more air can be passed through in a short time. The slit-shaped sheet opening can have a wider middle portion. Thereby, since the air pressure is more easily equalized, the valve opening time can be shortened.

[0013] According to some embodiments, a plurality of outlets are provided in the housing. Also, at least two valve assemblies are provided in the housing, and each of the at least two valve assemblies is associated with a respective outlet. Thereby, since there is no need to provide a wall between two adjacent outlets, the dimensions of the housing can be reduced and the outlets can be arranged close to each other.

[0014] According to one embodiment, the core is U-shaped with two legs. Thereby, a space-efficient mounting of the core can be obtained. According to some embodiments, the coil is wound only around one of the legs of the U-shaped core or around a part of one of the legs of the U-shaped core. Thereby, space is saved.

[0015] The present invention also extends to a manifold including a plurality of laminated valves according to the above. Thereby, an assembly that can be used for sorting applications can be provided, and since the distance between consecutive air outlets is very short, an air blast van can be provided at a narrow pitch.

Brief Description of the Drawings

[0016] Hereinafter, the present invention will be described in more detail by way of non-limiting examples with reference to the accompanying drawings.

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5a

Figure 5b

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11a

Figure 11b

Figure 11c

Best Mode for Carrying Out the Invention

[0018] Next, aspects of the present invention will be described in more detail. Like numbers refer to like components throughout. Well-known functions or structures are not necessarily described in detail to facilitate understanding and / or clarity. Further, it should be understood that the features described can be combined in any suitable way to meet different implementation requirements. Some components can be omitted in some embodiments. Further, although the exemplary embodiments described herein are generally illustrated by a rectangular housing, other designs can also be used.

[0019] FIG. 1 shows a side view of one embodiment of an electromechanical valve 10. The valve can typically be designed as a pneumatic valve. However, fluids other than air can also be envisioned. In the following exemplary embodiments, it is assumed that air is used as the pressurized fluid. The valve 10 is provided within a housing 12. In the following description, the housing 12 is designed to have one inlet and one air outlet for pressurized air. However, it is also envisioned that a housing can have multiple outlets. In embodiments having multiple outlets, each outlet can be controlled by a valve mechanism consisting of a controllable electromagnet. In such embodiments, the outlets can be stacked closer to each other.

[0020] In FIG. 1, the housing 12 has an air inlet P to which pressurized air is supplied. The housing 12 further has an air outlet A. In the embodiment of FIG. 1, the air inlet P and the air outlet A are arranged on the same plane. However, it is envisioned that other positions for the inlet P and the outlet A can exist. The housing 12 can be provided with an electrical connector 14 for supplying power to the electromechanical valve. Further, a positioning plug 16 can be provided on the housing 12. The positioning plug can be formed as a protrusion formed on the housing 12. The plug 16 can be used to position the valve 10 relative to some configuration or device.

[0021] The housing 12 can have a generally rectangular shape when viewed from the side. The dimensions can be small, with the width W being less than 100 mm, typically less than 50 mm. Similarly, the height H can be less than 100 mm, typically less than 50 mm. The housing 12 can be made of a non-magnetic / non-magnetizable material, such as an aluminum or plastic material.

[0022] It should be understood that the position of the inlet P is not limited, and the position of the inlet P depends on the purpose of use of the valve 10, and thus can be arranged at any appropriate position according to the field of use of the valve 10. Similarly, the outlet A can be arranged at any appropriate location according to the field of use of the valve 10.

[0023] FIG. 2 shows a top view of the valve 10. As can be seen, the valve 10 can be made very flat. The thickness T of the valve 10 can be on the order of several millimeters, such as 10 mm or less, about 5 - 6 mm, or 4 mm or less. In particular, the thickness T can be a fraction of the height H or width W of the valve. For example, the thickness T can be 1 / 5 or less of the height H and / or width W of the valve, or 1 / 10 or less of the height H and / or width W of the valve 10. A surface having such dimensions can be referred to as a narrow surface.

[0024] According to some embodiments, part or all of the inlet P, the outlet A, and the electrical connector 14 can be provided on a narrow side with respect to the other sides. In the embodiment shown in the present specification, the inlet P and the outlet A are provided on a common narrow surface. According to some embodiments, the electrical connector 14 can be provided on a narrow surface opposite to the narrow surface on which the inlet P and / or the outlet A are provided.

[0025] Figure 3 shows an exploded view of the valve 10. The valve 10 includes an air inlet P, an air outlet A, and an electrical connector 14 attached to a housing 12. In this exemplary embodiment, the housing 12 is formed by a first cover 22 facing the pneumatic side where the air inlet P and the air outlet A are located. The housing 12 is further formed by a second cover 24 where the electrical connector is disposed. When the housing 12 is formed by a plurality of parts as in this exemplary embodiment, different parts of the housing 12, here the first cover 22 and the second cover 24, can be joined together. The different parts of the housing can be joined by some fastening means such as screws 25 or some other means such as snap fits.

[0026] Inside the housing 12, a valve mechanism is provided. The valve mechanism includes an electromagnet, a stack of plates, and a valve seat. Accordingly, an electromagnet 30 is disposed inside the housing 12. The electromagnet 30 is here formed by a coil 32 wound around a core 34 including a magnetizable material such as iron or cobalt, or a soft magnetic material. The core 34 can also include a magnetizable alloy such as FeCo. The electromagnet 30 cooperates with a stack 36 of a plurality of layers of a magnetizable material forming a blade spring. The stack 36 can be formed by laminating thin plates including a magnetizable material such as iron or cobalt. The stack 36 is disposed on the valve seat 38.

[0027] The stack 36 can be fixed using some suitable means 37 such as screws or rivets. The valve seat can be provided with a sealing property or, according to some embodiments, is formed of a material having a sealing property such as a plastic material or a reinforced plastic material.

[0028] By activating the electromagnet 30, the stack 36 moves between a first position where the valve is closed and a second position where the valve is open, using a mechanism as described, for example, in WO2015126304. Thus, when an exciting current is supplied to the coil 32 surrounding the core 34 to magnetize the core 34, the stack 36 cooperates with the magnetized core 34, i.e., is attracted by the magnetized core 34 and opens the outlet A. When no exciting current is applied, the stack 36 returns to its initial position due to the inherent spring force. In this embodiment, the initial position is the position where the stack 36 is stationary relative to the valve seat 38 and forms a normally closed valve. In other words, the valve opens when an exciting current is applied to actuate the valve. In another embodiment, the valve can be designed to be normally closed such that the valve opens when no exciting current is supplied.

[0029] Accordingly, in the embodiment of FIG. 3, the valve seat 38 communicates the pressurized air inside the housing with the air outlet A. By activating the electromagnet formed by the core 34 around which the coil 32 is wound, when the stack 36 is lifted from its initial position by the magnetic force applied when the electromagnet is activated, the pressurized air inside the housing is discharged to the air outlet A through the valve seat 38. If a plurality of air outlets A are provided within the same housing 12, each air outlet A can be individually controlled by a separate assembly of the electromagnet 30, the stack of plates 36, and the valve seat 38. Thus, each air outlet A can be individually connected to such an assembly and thereby individually controlled. This allows the housing to be made simpler and the outlets to be placed closer together so that the housing walls can be removed when providing a plurality of air outlets. This enables a more compact design when providing a plurality of individually controlled outlets A.

[0030] FIG. 4 shows a top view of the valve 10 in an exploded state. In order to provide a very thin pneumatic valve having a thickness of only a few millimeters, such as less than 3 mm, the electromagnet 30 can have a core 34 with a flat design and can form a molded plate with a thickness of only 0.2 to 3 mm formed as a strip. Typically, the core can be thinner than 1 mm. However, the strip forming the core 34 can be wide and can have a width of at least 10 mm or more, such as 30 to 50 mm. In particular, the width is much larger than the thickness, thereby providing a thin core that can provide a large magnetic flux. For example, the width can be at least 5 times or 10 times the thickness of the plate-shaped core.

[0031] FIG. 5a shows detail C of FIG. 4. In order to provide a very thin pneumatic valve having a thickness of only a few millimeters, the electromagnet can have a core 34 with a flat design and can be formed with a thickness of only 0.2 to 3 mm. The core 34 typically has a generally rectangular cross-section and can be made thin to form a plate-like structure. A coil 32 is wound around at least a part of the flat plate-shaped core.

[0032] Also, as shown in FIG. 5a, the flat core 34 can be formed to have a protrusion formed by a lip 35 at the end facing the stack 36. The lip 35 can be offset from the plane of the flat plate core by a curved portion. The curved portion can be, for example, S-shaped. Thereby, the stack 36 can be disposed under the lip 35 so that the dimensions of the valve 10 can be further reduced. Thus, in such an embodiment, the coil is not wound around the core where the lip 35 is formed. The protrusion forms an attracting portion of the core 34. In other words, the protrusion is the portion of the core 34 with which the stack 36 cooperates to open and close the valve. In an alternative embodiment, the protrusion from the flat core 34 can be formed as an extension from the flat plate-shaped core 34. And the protrusion is formed thinner than the rest of the core and can be located at the top as shown in FIG. 5a. In other words, it is at the maximum distance from the valve sheet so as to increase the space between the valve sheet 38 and the attracting portion of the core 34. In FIG. 5a, the valve is not actuated and no exciting current is applied to the coil. At this time, the stack 36 is stationary with respect to the valve sheet 38.

[0033] According to some embodiments, the core 34 is generally U-shaped. The embodiment of FIG. 5a shows such a U-shaped core 34. The core 34 has two legs. As shown in FIG. 5a, one upper leg 34a around which the coil 32 is wound and a lower leg 34b. By providing the coil 32 on only one of the legs 34a, 34b, space can be saved and the valve 10 can be made thinner. The lower leg 34b can be fixed to the stack 36 and the valve sheet 38. The two legs 34a, 34b can be connected by a magnetizable material such as a material containing iron in a suitable manner. According to some embodiments, the U-shaped core is formed as one integral element.

[0034] When the core 34 is U-shaped, the stack 36 and the valve seat 38 can be arranged between the ends of the legs 34a, 34b. Thus, when an exciting current is applied to the coil 32 and the core is magnetized, the magnetic flux in the U-shaped core can be closed via the stack 36. Fig. 5a shows such an embodiment.

[0035] Fig. 5b shows a part of the core 34. Only the upper leg 34a is shown in Fig. 5b, and a connecting element 34c for connecting to the lower leg is provided at the rear part of the upper leg 34a. As can be seen in Fig. 5b, the lip 35 is offset from the main plane of the upper leg 34 via the bent portion 34d of the core 34.

[0036] Fig. 6 shows a view similar to Fig. 5. Here, an exciting current is applied so that the electromagnet operates. The stack 36 made of a magnetic material is attracted by the core 34 of the electromagnet so as to be displaced from the normal rest position shown in Fig. 5a. Thereafter, the valve of this exemplary embodiment is opened and air is discharged from the discharge port A. At the same time, since the coil can be arranged near the air path passing through the valve 10, the coil can be air-cooled by the air flowing through the valve 10.

[0037] Fig. 7 shows a detailed view of the plate 39 of the stack 36. The plate 39 can generally have a rectangular design. Fixing holes for fixing the stack to the valve housing or the core 34 can be provided in the part facing away from the core. The top plate 39a facing the core and lifted by the core can be different from the other plates 39. This top plate 39a can be shaped to hold the other plates together. Also, the top plate 39a can be made of a different material, particularly a non-magnetic material. Cuts 41 for adjusting the spring force of the stack 36 can also be provided in the top plate 39a. The cuts 41 can be divided by a bridge portion 42. Furthermore, the thickness of the top plate 39a can be different from that of the other plates 39 of the stack 36.

[0038] Figure 8 shows the valve seat 38. The valve seat can have at least one outlet channel 46 operably connected to the air outlet A. In the embodiment of Figure 8, a plurality of outlet channels are formed in the valve seat 38, and four outlet channels 46 are formed. The valve seat 38 has a valve seat opening 47 adapted to cooperate with the stack 36. The valve seat opening 47 forms an inlet channel to the valve. Thus, when the stack 36 is stationary relative to the valve seat opening 47, the air communication between the pressurized air from the air inlet P in the valve 10 and the air outlet A via the outlet channel 46 is closed. When the stack 36 is lifted from its stationary position (see Figure 6), air can flow through the valve 10 from the air inlet P through the seat opening 47, through the outlet channel 46, and to the air outlet A.

[0039] To increase the air flow, the seat opening 47 can be in the form of a slit having an elongated shape. Typically, the seat opening 47 can be elongated in the same direction as the plate of the stack 36. By making the seat opening 47 in the form of a slit, a high air flow can be achieved at a relatively low lift height of the stack 36 compared to the case where a circular seat opening is used. Further, a widened portion 49 can be formed in the middle of the slit-shaped seat opening 47. Thereby, when an excitation current is applied, air begins to flow quickly within the valve 10. This helps when lifting the stack in that the pressure is quickly equalized. As a result, the time from when no air flows into the bellows until air completely flows into the valve can be shortened.

[0040] By using the valve as described above, a sorting device can be obtained. In many applications, it is desirable to stack a large number of valves in close proximity. The valve 10 described in this specification is particularly suitable for such applications. FIG. 9 shows a state in which a plurality of valves 10 are stacked to form a manifold 50 for sorting articles such as grains. The sorting device formed by the manifold 50 can also be used for sorting other items by air blast.

[0041] Combine the manifolds 50 to form a manifold arrangement 60 having a plurality of stack valves arranged in parallel. By reducing the offset between the parallel stack valves, the incremental distance between consecutive valves can be reduced. For example, when the thickness of the valve is 6 mm and three parallel stack valves 10 are arranged with an offset pitch of 2 mm. In such an arrangement, the distance between two valves is only 2 mm. FIG. 10 shows such a manifold arrangement 60. In this way, with multiple rows of offset valves, the number of air passages can be increased over a distance. For example, with three rows of 6-mm valves, the offset is 2 mm, and with six rows, it is 1 mm.

[0042] By using the valve described in this specification, it becomes possible to stack valves with a narrow pitch. Furthermore, this design enables a relatively large air flow rate with respect to the small size of the valve. In other words, the flow rate relative to the size of the valve can be made larger than that of other types of valves. The valve has a long life and can withstand many cycles without losing its good characteristics. Furthermore, the response time is short compared to other types of valves. Therefore, for example, in sorting applications, sorting can be performed at a higher cycle (frequency). The fast response time and high air flow capacity are also effective in other applications. In air blow applications, spray applications, and dispensing applications, since the pressure gradually increases while the valve is open, an improved effect and accuracy can be obtained with a fast operation time. This is very important in sorting by air burst and in precision spraying such as inkjet. Figure 11 shows various ink patterns formed by air burst. Figure 11a shows a desirable "complete" ink dot. Figure 11b shows an ink dot formed when the pressure rises slowly. Finally, Figure 11c shows the result with a faster valve.

Claims

1. An electromechanical valve (10), The housing (20) includes a valve mechanism, The valve mechanism is, A core (34) of a magnetizable material surrounded by a coil (32) to which an excitation current is supplied, A stack (36) of plates of magnetizable material fixed to the first end, Including a valve seat (38), The plate stack (36) is provided in the space between the core (34) and the valve seat (38), and when an excitation current is supplied to the coil (32), the plate stack (36) is displaced from the valve seat, thereby opening and closing the valve in accordance with the excitation current supplied to the coil (32). The plate stack provides a return spring force when the plate stack is attracted to the energized coil. The core (34) is plate-shaped with a thickness of 3 mm or less. Electromechanical valve (10).

2. The core has an induction section facing the plate stack (36), and no coil is wound around the induction section. The electromechanical valve (10) according to claim 1.

3. The attracting part forms a protrusion from the core. The electromechanical valve (10) according to claim 2.

4. The projection is a lip (35) offset from the plane of the core. The electromechanical valve (10) according to claim 3.

5. The core thickness is less than 1 mm. The electromechanical valve (10) according to claim 1.

6. The valve seat (38) has a slit-shaped seat opening (47). The electromechanical valve (10) according to claim 1.

7. The slit-shaped sheet opening (47) has a wider intermediate portion (49), The electromechanical valve (10) according to claim 6.

8. Multiple outlets are provided within the housing (12). At least two valve assemblies are provided within the housing, and each of the at least two valve assemblies is associated with its respective outlet. The electromechanical valve (10) according to claim 1.

9. The core (34) is U-shaped and has two legs (34a, 34b). The electromechanical valve (10) according to claim 1.

10. The coil is wound around only one of the legs of the U-shaped core, or only a portion of one of the legs of the U-shaped core. The electromechanical valve (10) according to claim 9.

11. The core (34) has a cross-section in which the width of the core is at least five times its thickness. The electromechanical valve (10) according to claim 1.

12. A sorting manifold comprising a plurality of electromechanical valves (10) according to any one of claims 1 to 11, stacked on top of each other.

Images