Solenoid valve

Abstract

An electromagnetic valve (1) with: a movable core (40) having a first end on one side in an axial direction (L) and a second end on the other side in the axial direction (L), wherein the movable core (40) moves in response to an excitation of an electromagnet in the axial direction (L), a valve body (10) with a plurality of ports (A, P, R) into or from which a pressure fluid flows, and a valve box (11) with which the ports (A, P, R) are connected, and a valve disc (3) which is received in the valve box (11), wherein the valve disc (3) moves towards and away from a valve seat (12) in the valve box (11) in accordance with the displacement of the movable core in the axial direction (L) in order to change connection states between the ports (A, P, R), wherein the movable core (40) comprises an iron core (43) which is located closer to the first end and is formed into a plate with a substantially rectangular cross-section, and a valve holding section (45) which is located closer to the second end and merges into the iron core (43), wherein both surfaces of the movable core (40), which are oriented in a thickness direction, are single, flat, parallel surfaces and extend continuously from the iron core (43) to the pair of retaining arms (45), and wherein the valve disc (3) is held between the pair of retaining arms (45) characterized in that the valve retaining section (45) has a pair of retaining arms (45) and wherein the pair of retaining arms (45) is arranged side by side in a width direction of the movable core (40) such that they are parallel to each other and integrally formed with the iron core (43).

Description

Technical field

[0001] The present invention relates to an electromagnetic valve which excites an electromagnet to move a movable core and which actuates a valve disc in a direction in which the movable core is moved in order to change the connection state between several ports. State of the art

[0002] An electromagnetic valve which excites an electromagnet to move a movable core and which actuates a valve disc in a direction in which the movable core is moved in order to change connection states between several ports is well known as described in patent document (PTL) 1.

[0003] The movable core of the solenoid valve disclosed in PTL 1 has a substantially rectangular cross-section, and the valve disc, including an elastic section made of plastic material, is axially fixed to one end of the movable core. A valve chamber, which receives the valve disc, is formed within a valve body. Several ports are connected to the valve chamber. An opening, connected to one of the ports, is formed in a bottom surface of the valve chamber. A valve seat, which surrounds the circumference of the opening and to which the elastic section of the valve disc moves, is provided.

[0004] The familiar solenoid valve typically has a complex structure for the connection between the moving core and the valve disc, and its design usually results in high manufacturing costs. Therefore, further reductions in manufacturing costs are just as desirable as improvements towards a more efficient design.

[0005] Another solenoid valve is known from DE 602 08 965 T2. List of documentsPatent literature

[0006] PTL 1: JP 2003 - 172 472 A Summary of the invention: Technical problem

[0007] It is a technical object of the present invention to propose, at low cost, an electromagnetic valve which is improved with regard to a more reasonably designed structure, wherein the electromagnetic valve has a structure which actuates a valve disc according to the displacement of a movable core by exciting an electromagnet. Solution to the task

[0008] To solve the above-mentioned problem, an electromagnetic valve according to the present invention comprises a movable core having a first end on one side in an axial direction and a second end on the other side in the axial direction, wherein the movable core moves in the axial direction according to an excitation of the electromagnet, a valve body with a plurality of ports into or out of which a pressure fluid flows, and a valve box with which the ports communicate, as well as a valve disc which is received in the valve box, wherein the valve disc moves towards and away from a valve seat in the valve box when the movable core moves in the axial direction in order to change connection states between the ports.The movable core comprises an iron core located near the first end and formed into a plate with a substantially rectangular cross-section, and a valve retention section located near the second end and merging into the iron core. The valve retention section has a pair of retention arms. The pair of retention arms is arranged side by side in a width direction of the movable core such that they are parallel to each other and are integrally formed with the iron core. Both surfaces of the movable core that point in a thickness direction are single, flat, parallel surfaces that extend continuously from the iron core to the pair of retention arms. The valve disc is held between the pair of retention arms.

[0009] In the present invention, the iron core and the valve retention section of the movable core are seamlessly integrated (formed in one piece), thus reducing the number of components and simplifying the design or shape of the movable core. This, in turn, reduces manufacturing costs.

[0010] According to the present invention, the valve disc is preferably held between the pair of retaining arms such that it is axially displaceable relative to the retaining arms. An elastic element arranged in the valve housing positions the valve disc on the valve seat by pressing the valve disc towards the valve seat. Each pair of retaining arms has a valve engagement section that engages with an engagement section of the valve disc that rests on the valve seat when the movable core moves in a direction opposite to the direction in which the elastic element presses the valve disc, thus separating the valve disc from the valve seat against the preload force of the elastic element.

[0011] As described above, instead of being attached to the movable core, the valve disc is provided separately, allowing for a more flexible design of the valve holding section of the movable core and enabling a simpler construction or shape.

[0012] When the valve disc is placed on the valve seat by the elastic element, when the movable core is moved in the direction in which the elastic element pushes the valve disc, the valve engagement section in particular is not in contact with the valve disc.

[0013] This prevents the kinetic energy of the moving core from being directly transferred to the valve disc when the disc strikes the valve seat. This reduces the external force exerted on the valve disc in the axial direction. This prevents the valve disc from wearing down or becoming irreversibly deformed (permanently deformed) due to repeated external force. It also prevents the axial dimension of the valve disc from changing over time. Consequently, it prevents the stroke of the moving core, i.e., the distance between the valve seat and the valve disc, from varying. This minimizes any variation in the flow rate of the fluid through the valve seat or the response behavior of the solenoid valve.

[0014] According to a preferred embodiment of the present invention, the valve seat is provided on a bottom wall surface of the valve housing, which faces the second end of the movable core. The free end faces of the retaining arms are flat surfaces perpendicular to an axis. The bottom wall surface has an arm contact surface. The arm contact surface is a flat surface parallel to the free end faces of the retaining arms. The free end faces move towards and away from the arm contact surfaces in accordance with a displacement of the movable core. When the valve disc contacts the valve seat as the movable core is displaced towards its second end, the free end faces of the retaining arms rest against the arm contact surface, and a gap with a size in the axial direction that is smaller than the stroke of the movable core is formed between the valve engagement section and the engagement section of the valve disc.

[0015] This ensures that the movable core is accurately positioned relative to the valve body when the valve disc strikes the valve seat to engage. This allows for more precise control of the solenoid valve's response.

[0016] According to a preferred embodiment of the present invention, a first valve seat is formed on the bottom wall surface of the valve housing, and a second valve seat is provided in the valve housing at a position facing the first valve seat along its axis. The valve disc is arranged between the first and second valve seats and is continuously pressed towards the first valve seat by the elastic element. The valve engagement section of the pair of retaining arms is formed by a thin plate that is elastic in the axial direction.The valve engagement section is brought into engagement with the engagement section of the valve disc seated on the first valve seat when the movable core moves from the second end to the first end, and separates the valve disc from the first valve seat against the preload force of the elastic element to cause the valve disc to seat on the second valve seat.

[0017] Thus, the valve engagement section provided on the pair of retaining elements is formed by a thin plate that is elastic in the axial direction. When the valve disc abuts the second valve seat to seat, the external force exerted on the valve disc in the axial direction can be absorbed and reduced by the valve engagement section. This design can therefore prevent, as far as possible, wear or irreversible deformation (permanent deformation) of the valve disc when such an external force is repeatedly applied to it.

[0018] According to a preferred embodiment of the present invention, the pair of retaining arms comprises engagement hooks at their free end sections, projecting away from one another. A cap element, formed from a thin metal plate with a substantially U-shaped cross-section, is arranged between the free end sections of the pair of retaining arms. The cap element has a pair of engagement openings that engage with the engagement hooks of the pair of retaining arms, and a valve opening formed between the pair of engagement openings, which allows the valve disc to be placed on the first valve seat through the valve opening. The valve engagement section is provided on a circumferential section of the valve opening. The engagement section is provided on an end face of the valve disc that faces the first valve seat.

[0019] Thus, the cap element, formed from a thin metal plate and having a simple structure, enables the valve disc to be attached to the valve holding section of the movable core and the formation of the valve engagement section.

[0020] In an electromagnetic valve according to the present invention, the valve disc preferably comprises a pair of guide grooves that open in opposite directions and extend in the axial direction, wherein the pair of retaining arms is inserted into the pair of guide grooves in such a way that they are movable relative to each other in the axial direction, and wherein the valve disc is held between the pair of retaining arms in such a way that it can slide in the axial direction.

[0021] This design prevents movement of the valve disc in a direction perpendicular to the axis of the movable core and also eliminates any deviation of the valve disc's axis. This ensures that the valve disc is securely seated on the valve seat.

[0022] The valve seat is preferably located on a bottom wall surface of the valve box facing the second end of the movable core. The pair of retaining arms includes engagement hooks projecting away from each other. A cap element formed from a thin metal plate with a substantially U-shaped cross-section is positioned between the free end sections of the pair of retaining arms. The cap element has a pair of engagement openings that engage with the engagement hooks of the pair of retaining arms, and a valve opening formed between the pair of engagement openings, which allows the valve disc to be placed on the first valve seat through the valve opening. The valve engagement section is located on a circumferential section of the valve opening.The valve engagement section engages with an end face of the valve disc facing the valve seat when the movable core moves from the second end to the first end.

[0023] This allows the cap element, formed from a thin metal plate and having a simple structure, to be attached to the valve retaining section of the movable core and to form the valve engagement section.

[0024] In an electromagnetic valve according to the present invention, the electromagnetic valve preferably comprises a solenoid section and the solenoid section comprises a coil body and a solenoid ring, wherein the coil body has a central hole into which an iron core of the movable core is inserted so that it can slide in the axial direction, wherein the coil body has a coil wound around the outer circumference of the coil body and wherein the solenoid ring is arranged so that it surrounds an opening of the central hole at an end of the coil body that is closer to the valve body.The central hole of the coil former has a substantially rectangular cross-section and features a pair of first inner surfaces and a pair of second inner surfaces. The pair of first inner surfaces faces a pair of faces of the iron core that are parallel to each other and extend along both sides in a thickness direction of the iron core. The pair of second inner surfaces faces a pair of end faces of the iron core that are parallel to each other and extend along both ends in a width direction of the iron core. Stepped sections are provided on both end sections of the pair of first inner surfaces in a width direction of the first inner surfaces to reduce the spacing between the first inner surfaces to a distance shorter than the spacing between middle sections. The stepped sections transition into the second inner surfaces.A pair of convex threads extending in the axial direction are provided on the pair of second inner surfaces. The pair of end faces of the iron core are held by the pair of convex threads so that they can slide in the axial direction. The pair of faces of the iron core are held by the stepped sections so that it can slide in the axial direction. The iron core extends through the magnetic ring and has a free (distal) end that projects toward the valve body.

[0025] In this design, both end faces of the movable core and both side sections of the pair of faces are held by the convex threads and the stepped sections so that they can slide in the central hole of the coil former. This reliably prevents the axis of the movable core from shifting.

[0026] Preferably, a pair of projecting engagement walls, extending axially from the pair of second inner surfaces, is provided at the opening of the central hole. The magnet ring has an engagement hole section into which the projecting engagement walls are inserted. The magnet ring is positioned coaxially with the coil former because the projecting engagement walls are inserted into the engagement hole section. This design can more reliably prevent a reduction in the efficiency of the magnet section caused by contact between the moving core and the magnet ring. Advantageous effects of the invention

[0027] As described above, the solenoid valve according to the present invention can reduce the number of components and simplify the design or shape of the moving core by seamlessly integrating the iron core and the valve retention section of the moving core. This design can reduce manufacturing costs. Brief description of the drawings Fig. Figure 1 is a section through an electromagnetic valve according to an embodiment of the present invention in a demagnetized state. Fig. Figure 2 is a vertical section through the solenoid valve according to Fig. 1. Fig. 3 is an enlarged schematic section through a main section, showing a state around a valve box in Fig. 1 shows. Fig. Figure 4 is a side section through the solenoid valve in an energized state. Fig. Figure 5 is a vertical section through the solenoid valve according to Fig. 4. Fig. 6 is a schematic section through a main section, showing the state around a valve box in Fig. 4 shows. Fig. Figure 7 is a schematic perspective exploded view of components relating to a magnetic section according to the present embodiment. Fig. Figure 8 is an enlarged section of a connected segment along line VIII-VIII in Fig. 4. Fig. Figure 9 is a schematic perspective view of the movable core before a cap element is attached to a pair of support arms. Fig. Figure 10 is a schematic perspective view of the state when the state is in Fig. Nine guide grooves of a valve disc are inserted between the pair of retaining arms. Fig. Figure 11 is a schematic perspective view of the state when the cap element changes from the state in Fig. 10 extends between the pair of support arms. Fig. Figure 12 is a schematic section of the state when the movable core is received in a central hole of a coil former. Fig. Figure 13 is a schematic top view of an opening of the coil body, which is located closer to the valve body. Fig. 14 is an enlarged section through a main section along line XIV-XIV in Fig. 1. Fig. Figure 15 is a schematic perspective view of the state in which a magnetic ring is attached to engagement projections of the coil body. Description of embodiments

[0028] The Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7, Fig. 8, Fig. 9, Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14 to Fig. Figure 15 illustrates an electromagnetic valve according to an embodiment of the present invention. An electromagnetic valve (solenoid valve) 1 according to the present invention essentially comprises a main valve section 2 with a valve disc 3 for switching a flow passage through which a pressurized fluid, for example air, flows, and a solenoid section 7 which actuates the valve disc 3 of the main valve section 2. The main valve section 2 and the solenoid section 7 are connected in series in one direction along an axis L of the electromagnetic valve 1.

[0029] As can be seen from the Fig. 1 and Fig. As shown in section 2, the main valve section 2 comprises a valve body 10 with a rectangular cross-section. A supply port P, an outlet port A, and an exhaust port R are formed in a first side face of the valve body 10. A valve housing 11, to which the supply port P, the outlet port A, and the exhaust port R are connected, is formed within the valve body 10. A seal 29 is attached to these ports.

[0030] As in Fig. 1 and Fig. As shown in Figure 4, a first valve seat 12 and a second valve seat 13, towards and away from which the valve disc 3 moves, are provided in the valve housing 11. The first valve seat 12 and the second valve seat 13 are arranged so that they face each other in the direction of the axis L. The first valve seat 12 is located on a bottom wall surface 14 of the valve housing 11 such that it surrounds a supply through-hole 15 in a substantially central section of the bottom wall surface 14 and projects towards the solenoid section 7. The supply through-hole 15 is connected to a supply connection passage 16, which is located closer to a base of the valve body 10 than the bottom wall surface 14. The supply connection passage 16 is connected to the supply port P. Thus, the supply port P communicates with the valve housing 11 through the supply through-hole 15.

[0031] On the other hand, the second valve seat 13 is provided on a holder 17, which is attached to the valve box 11. The holder 17 is made of a resin or plastic material and is received in the valve box 11 at a section that is closer to an opening edge of the valve box 11 than to the valve disc 3 (closer to the solenoid section 7). The holder 17 comprises an annular outer circumferential section 20 that fits into the inner circumferential wall of the valve box 11, and a projection 19 that is provided within the annular outer circumferential section 20 such that it projects towards the first valve seat 12.

[0032] As in Fig. 1 and Fig. As shown in Figure 2, an exhaust passage 21, which communicates with the exhaust port R, is formed on a front section (tip) of the projection 19 of the holder 17. The second valve seat 13, which has an annular shape, is provided around the exhaust passage 21. An annular groove 22 is formed in the annular outer circumferential section 20. Sealing elements 23 are attached to both sides of the annular groove 22 in the direction of the axis L to hermetically seal the interior of the valve housing 11. The annular groove 22 communicates with an exhaust connection passage 24, which communicates with the exhaust passage 21. Thus, the exhaust port R communicates with the interior of the valve housing 11 via the annular groove 22, the exhaust connection passage 24, and the exhaust passage 21.Between the projection 19 and the annular outer circumferential section 20 is a pair of insertion holes 25, through which a pair of retaining arms 45 of a later described movable core 40 is inserted (cf. . Fig. 1 and Fig. 9), trained.

[0033] As in Fig. 1 and Fig. As shown in Figure 4, the valve disc 3, which is a poppet or poppet valve, is located in the valve body 11 in the space between the first valve seat 12 and the second valve seat 13. The valve disc 3 is made of a resin or plastic material with elastic and sealing properties, such as rubber, and is shaped into an essentially rectangular form. The valve disc 3 moves towards and away from the first valve seat 12 and the second valve seat 13 to change the connection states between the ports P, A, and R. An elastic element 26, formed by a coil spring, is arranged between the valve disc 3 and the holder 17, fixed to the valve body 10. The elastic element 26 continuously pushes the valve disc 3 towards the first valve seat 12.When the magnetic section 7 is in a non-excited state (demagnetized state), the valve disc 3 is placed on the first valve seat 12 by the preload force of the elastic element 26 (cf. . Fig. 1 to Fig. 3) In the present embodiment, the base end of the projection 19 of the holder 17 serves as a spring seat for the elastic element 26.

[0034] As in Fig. As shown in Figure 8, the valve disc 3 comprises the end faces of the valve disc 3 in the width direction (left-right direction). Fig. 8) A pair of guide grooves 3a opening in opposite directions and extending along the axis L. When a pair of retaining arms 45 of the movable core 40, described below, are inserted into the guide grooves 3a, the valve disc 3 is held between the pair of retaining arms 45 so that it can slide along the axis L. This assembly, including the guide grooves 3a, prevents the valve disc 3 from moving in a direction perpendicular to the axis of the movable core 40 and avoids any displacement (tilting) of the axis of the valve disc 3. Thus, the valve disc 3 can be securely seated on the first valve seat 12 and the second valve seat 13.

[0035] The following section describes magnetic section 7. As in Fig. 1 and Fig. As shown in Figure 7, the magnetic section 7 has a magnetic cover 30 with a rectangular cross-section, the first end of which (upper end in Fig. 1) is closed in the direction of the axis L by a cap 31. As in Fig. As shown in Figure 1, within the magnetic cover 30 are provided a coil former 60 around which an excitation coil 32 is wound, a stationary core 35 which is mounted in a central hole 60a of the coil former 60, the movable core 40 which is inserted into the central hole 60a so that it can slide in the direction of the axis L, and a magnetic ring 80 which is provided at one end of the coil former 60 near the valve body 10 so that it surrounds the opening of the central hole 60a. As shown in Fig. 1 and Fig. As shown in Figure 4, annular grooves 60b are formed between the cap 31 and the coil former 60, and between the coil former 60 and the magnet ring 80. Sealing elements 38 are installed in the respective annular grooves 60b. A pair of coil terminals 39, which are electrically connected to the excitation coil 32, project from the side surface of the magnet cover 30. Conducting wires are connected to the coil terminals 39.

[0036] The stationary core 35 is made of a metal material and is formed into an essentially rectangular plate. The stationary core 35 comprises flanged sections 35a at a first end (upper end in Fig. 1) in the direction of the axis L. The stationary core 35 is held between the coil former 60 and the cap 31, with the flange sections 35a engaging with an end section of the coil former 60 near the cap 31.

[0037] On the other hand, the movable core 40 is displaced in the direction of the axis L by excitation and demagnetization effects of the magnetic section 7. The displacement of the movable core 40 in the direction of the axis L places the valve disc 3 onto the first valve seat 12 and the second valve seat 13. When the excitation coil 32 is in a switched-on state (excited state), as described in the Fig. 4, Fig. 5 to Fig. As shown in Figure 6, in particular the movable core 40 is attracted to the stationary core 35, so that the valve disc 3 releases the first valve seat 12 and rests on the second valve seat 13, so that the supply port P and the outlet port A are connected to each other through the valve box 11.

[0038] If, on the other hand, the excitation coil 32 is not switched on (demagnetized state), as is the case in the Fig. 1, Fig. 2 to Fig. As shown in Figure 3, the movable core 40 is lifted off the stationary core 35, so that the valve disc 3 releases the second valve seat 13 and is placed on the first valve seat 12. The outlet port A and the exhaust port R are connected to each other via the valve box 11.

[0039] The movable core 40 has a first end at one end in the direction of the axis L and a second end at the other end in the direction of the axis L. An iron core 43 with a plate shape and a substantially rectangular cross-section is provided at the side of the first end. Valve retaining sections (retaining arms 45), projecting in the direction of the axis L beyond an end face 43a of the iron core 43, are provided at the side of the second end. The iron core 43 faces the stationary core 35 and is attracted to or separated from the stationary core 35 when the excitation coil 32 is switched on or off.

[0040] As in Fig. 1 and Fig. As shown in Figure 4, the valve retaining section comprises a pair of retaining arms 45 that seamlessly transition into the iron core 43. These retaining arms 45 are located side by side at both ends of the movable core 40 in the lateral direction (left-right direction). Fig. 1) arranged so that they are symmetrical on both sides relative to the axis L. The movable core 40 is formed from a single magnetic metal plate. By stamping out this metal plate, the iron core 43 and the valve retaining section (i.e., the retaining arms 45) are formed in one piece. As in Fig. 2 and the Fig. 9, Fig. 10 to Fig. As shown in Figure 11, there is thus a pair of surfaces (side faces) 50 which are parallel to each other on both sides in the thickness direction of the movable core 40 (left-right direction). Fig. 2) run from individual flat surfaces that extend continuously from the iron core 43 to the retaining arms 45.

[0041] As in Fig. 1 and Fig. As shown in Figure 4, the pair of retaining arms 45 extends in the valve box 11 of the valve body 10 through the pair of insertion holes 25 that open in the holder 17 and is inserted inside the valve box 11 into the pair of guide grooves 3a (see Figure 4). Fig. 8), which are formed in the valve disc 3, so that they are displaceable in the direction of the axis L relative to the valve disc 3. Thus, the valve disc 3 is held between the pair of retaining arms 45 so that it can slide in the direction of the axis L.

[0042] Instead of being fixed to the movable core 40, the valve disc 3 is movably held by the movable core, so that the valve holding section of the movable core 40 can be designed more freely and a simpler structure or shape can be achieved.

[0043] As in Fig. 3 and Fig. As shown in Figure 6, the pair of retaining arms 45 each comprises engagement hooks 47 at their free ends, projecting in directions away from each other. Each of the engagement hooks 47 has an inclined surface 47a at its free end section. The inclined surface 47a is gradually inclined towards the axis L as it approaches a free end surface 46 of the corresponding retaining arm 45. Each of the engagement hooks 47 has an engagement surface 47b at its base end section, which is formed at an end surface perpendicular to the axis L.

[0044] As in Fig. 3, Fig. 6 and Fig. As shown in Figure 9, a cap element 70 extends between the free end sections of the pair of retaining arms 45. The cap element 70 is formed from an elastic thin metal plate with a substantially U-shaped cross-section. The cap element 70 comprises a pair of engagement openings 71 that engage with the engagement hooks 47, and a valve opening 72 located between the pair of engagement openings 71. The valve disc 3 is placed onto the first valve seat 12 through the valve opening 72.

[0045] As in Fig. As shown in Figure 9, the cap element 70 comprises a thin, plate-shaped valve engagement section 73 extending in a direction perpendicular to the axis L and elastic in the direction of the axis L, and a pair of locking sections 74 extending from the left and right ends of the valve engagement section 73 in a substantially perpendicular direction. Connecting sections between the valve engagement section 73 and the locking sections 75 are slightly arcuate. When the movable core 40 is attracted to the stationary core 35, the valve engagement section 73 engages with a contact surface 4 (end surface facing the first valve seat 12) of the valve disk seated on the first valve seat 12, as shown in Figure 9. Fig. Figure 6 shows that the valve disc 3 is lifted from the first valve seat 12 against the preload force of the elastic element 26 and placed on the second valve seat 13. The valve engagement section 73 has the valve opening 72. As shown in Fig. As shown in Figure 3, the valve disc 3 can be placed on the first valve seat 12 through the valve opening 72.

[0046] As in Fig. As shown in Figure 9, the engagement openings 71 are rectangular and formed on sections over the valve engagement sections 73 and the locking sections 74. Curved sections 75, which are bent outwards, are formed at the free ends of the locking sections 74. As described above, the cap element 70, which is formed from a thin metal plate and has a simple structure, allows the valve disc 3 to be attached to the valve retaining section (retaining arms 45) of the movable core 40 and forms the valve engagement section 73.

[0047] The cap element 70 is attached between the retaining arms 45 as described below. First, as shown in Fig. As shown in Figure 9, the movable core 40, the holder 17, the elastic element 26, the valve disc 3, and the cap element 70 are prepared. The elastic element 26, formed by the coil spring, is attached to the outer circumference of the projection 19 of the holder 17. The axes of the movable core 40 and the holder 17, to which the elastic element 26 is attached, are then aligned with each other, and the pair of retaining arms 45 is inserted from one side of the holder 17 into the insertion holes 25 of the holder 17 in the direction of axis L (the side opposite the projection 19). Simultaneously, the valve disc 3 is pressed against the preload force of the elastic element 26 from the side opposite the movable core 40 (the retaining arms 45) (from the side of the projection 19) toward the holder 17. Thus, the grooves 3a of the valve disc 3 are placed onto the pair of retaining arms 45, which extend from the insertion holes 25 (cf. ). Fig. 10). In this state, the cap element 70 is attached between the retaining arms 45.

[0048] When the cap element 70 is pressed relative to the retaining arms 45, with the opening side (side of the locking sections 74) of the cap element 70 facing the free end surfaces 46 of the retaining arms 45, the following occurs, as shown in Fig. Figure 10 shows the curved sections 75 of the pair of locking sections 74 of the cap element 70 on the inclined surfaces 47a of the engagement hooks 47 at the free end sections of the retaining arms 45. This elastically increases the distance between the pair of locking sections 74. Then, the opening edges (free ends) of the engagement openings 71 of the locking sections 74 are shifted to the positions of the engagement surfaces 47b of the engagement hooks 47, and the positions of the engagement opening 71 and the positions of the engagement hooks 47 are aligned with each other. Thus, the widened locking sections 74 elastically return to their original position, and the engagement hooks 47 enter the engagement openings 71, as shown in Figure 10. Fig. Figure 11 is shown. This completes the attachment of the cap element 70 to the retaining arms 45.

[0049] As in the Fig. 3, Fig. 4 and Fig. As shown in Figure 6, the flat end surfaces 46 of the pair of retaining arms 45 are flat surfaces perpendicular to the axis L. On the other hand, a pair of arm contact surfaces 27 is formed on the bottom wall surface 14 of the valve box 11, which faces the free end surfaces 46. The free end surfaces 46 move away from these contact surfaces. The pair of arm contact surfaces 27 are flat surfaces parallel to the free end surfaces 46 of the retaining arms 45. The arm contact surfaces 27 are provided on both sides of the first valve seat 12 on the bottom wall surface 14, that is, on both sides of the valve body 10 in the lateral direction (left-right direction). Fig. 3) and protrude from the magnetic section 7. The height of the arm contact surfaces 27, by which the arm contact surfaces 27 project from the bottom wall surface 14 into the valve box 11, is less than the height by which the first valve seat 12 projects from the bottom wall surface 14 into the valve box 11. In particular, the arm contact surfaces 27 are arranged closer to the bottom wall surface 14 than the first valve seat 12.

[0050] As in the Fig. 1 and Fig. As shown in Figure 3, in the present embodiment the free end surfaces 46 of the pair of retaining arms 45 rest against the arm contact surfaces 27 when the movable core 40 is moved to the second end (to the first valve seat 12) and the valve disc 3 is placed on the first valve seat 12. As shown in Figure 3, the free end surfaces 46 of the pair of retaining arms 45 rest against the arm contact surfaces 27 when the movable core 40 is moved to the second end (to the first valve seat 12) and the valve disc 3 is placed on the first valve seat 12. Fig. As shown in Figure 3, at this time the valve engagement section 73 of the cap element 70 is not in contact with the engagement section 4 of the valve disc 3. A gap G, which is smaller than a stroke of the movable core 40, is formed between the valve engagement section 73 and the engagement section 4.

[0051] As in Fig. As shown in Figure 12, the central hole 60a of the coil former 60, which receives the movable core 40, has a substantially rectangular cross-section with a pair of first inner surfaces 61 and a pair of second inner surfaces 65. The first inner surfaces 61 face a pair of surfaces 50 on both sides of the movable core 40 in the thickness direction, and the second inner surfaces 65 face a pair of end surfaces 51 that are parallel to each other at both ends of the movable core 40 (iron core 43) in the width direction (left-right direction). Fig. 12) run, facing.

[0052] On both side sections 62 of the pair of first inner surfaces 61 in the width direction, stepped sections 64 are formed to reduce the distance between the first inner surfaces 61 so that it is smaller than the distance between middle sections 63 held between the two side sections 62. The stepped sections 64 extend in the direction of the axis L and are connected to the second inner surfaces 65 of both side sections 62 of the first inner surfaces 61 in the circumferential direction of the central hole 60a. A pair of convex threads 66 is formed on the pair of second inner surfaces 65 such that they extend in the direction of the axis L. The convex threads 66 are formed on the second inner surfaces 65 such that they face each other (facing inwards) and have a circular arc cross-section.

[0053] When the iron core 43 of the movable core 40 is inserted into the central hole 60a of the coil former 60, the pair of end faces 51 are held by the pair of convex threads 66 so that they can slide in the direction of the axis L, and the pair of surfaces 50 are held by the stepped sections 64 so that they can slide in the direction of the axis L. The movable core 40 extends through the magnet ring 80 so that its free end projects towards the valve body 10.

[0054] In the present embodiment, both end faces 51 of the movable core 40 and both side sections of the pair of surfaces 50 are held by the convex threads 66 and the stepped sections 64 so that they can slide in the central hole 60a of the coil former 60. This effectively prevents displacement of the axis of the movable core 40.

[0055] As in Fig. 7 and the Fig. 13, Fig. 14 to Fig. As shown in Figure 15, a pair of projecting engagement walls 67 are provided in the opening of the central hole 60a, facing the valve body 10. The projecting engagement walls 67 extend from the pair of second inner surfaces 65 in the direction of the axis L. The magnet ring 80, which is designed to surround the central hole 60a, has an engagement hole section 81. When the projecting engagement walls 67 are inserted into the engagement hole section 81, the magnet ring 80 is positioned so that it is coaxial with the coil body 60.

[0056] As in Fig. 7 and the Fig. 13, Fig. 14 to Fig. As shown in Figure 15, the protruding engagement walls 67 of the coil body 60 each have a side wall section 68 facing both side sections 51 of the movable core 40, and semicircular arcuate wall sections 69 on both sides (upper and lower sides in Fig. 13) of side wall section 68. As in Fig. 7 and Fig. 14 and Fig. As shown in Figure 15, the engagement hole section 81 of the magnetic ring 80 has, on the other hand, a pair of first surface sections 82 extending parallel to each other, so that they face the pair of surfaces 50 of the movable core 40, and second surface sections 83 on both sides of the first surface sections 82. The distance between the first surface sections 82 is greater than the thickness of the movable core 40 (distance between the pair of surfaces 50) and the distance between the middle sections 63 of the first inner surfaces 61 of the central hole 60a.

[0057] Every second surface section 83 comprises a straight section 84, at which the engagement projection 67 engages and which extends in the direction perpendicular to the first surface section 82, and semicircular arc sections 85 on both sides of the straight section 84. The straight section 84 engages with the outer circumferential surface of the side wall section 68 of the associated projecting engagement wall 67. The arc sections 85 engage with the outer circumferential surfaces of the arc-shaped end sections 69 of the projecting engagement wall 67.

[0058] As in Fig. As shown in Figure 14, the magnetic ring 80 has an outer circumferential surface, which is essentially rectangular in a plan view, and a pair of recesses 86 in both side faces of the outer circumferential surface in the width direction. The pair of recesses 86 engages with a pair of inwardly directed projections 28 provided in the valve box 11 of the valve body 2.

[0059] When the magnetic ring 80 is attached to the opening of the central hole 60a, as shown in Fig. As shown in Figure 14, the engagement projections 67 of the coil former 60 and the engagement hole section 81 of the magnetic ring 80 engage with each other in the manner described above, and the recesses 86 and the inwardly directed projections 28 engage with each other. Thus, the axes of the magnetic ring 80 and the central hole 60a of the coil former 60 are aligned with each other. When the magnetic ring 80 is attached to the opening of the coil former 60, the engagement projections 67 are positioned between the two side sections 51 of the movable core 40 and the second surface sections 83 of the magnetic ring 80. In this state, a gap is formed between the first surface sections 82 of the magnetic ring 80 and the respective associated surface 50 of the movable core 40. This configuration prevents the movable core 40 and the magnetic ring 80 from coming into direct contact with each other.This reliably prevents a decrease in the efficiency of magnetic section 7.

[0060] While the excitation coil 32 in the solenoid valve 1 with the above-described setup is not switched on (demagnetized state), as is the case in Fig. 1 and Fig. As shown in Figure 2, the movable core 40 is spaced apart from the stationary core 35. When the excitation coil 32 is in the demagnetized state, the valve disc 3 rests on the first valve seat 12, with the preload force of the elastic element 26 applied to it by the holder 17 to block a connection between the supply port P and the valve box 11. At this time, the second valve seat 13, which is arranged so that it faces the first valve seat 12 in the direction of the axis L, is open, and the outlet port A is connected to the outlet port R through the outlet passage 21 and the outlet connection passage 24 in the valve box 11. Thus, the pressurized fluid in the valve box 11 is discharged to the outside through the outlet port R, which is connected to the environment.

[0061] In the present embodiment, when the excitation coil 32 is in the demagnetized state as described in Fig. As shown in Figure 3, the free end surfaces 46 of the pair of retaining arms 45 of the movable core 40 rest against the pair of arm contact surfaces 27 of the bottom wall section 14 of the valve box 11. The valve disc 3 sits on the first valve seat 12 in the valve opening 72 of the cap element 70 between the pair of retaining arms 45. At this time, the end surface (attack section 4) of the valve disc 3, which faces the first valve seat 12, and the valve engagement section 73 of the cap element 70 are not in contact with each other, and a gap G, which is smaller than one stroke of the movable core 40, is formed between the attack section 4 and the valve engagement section 73.

[0062] When the excitation coil 32 is switched on in this state, so that it is in the energized state, the movable core 40 is attracted to the stationary core 35 and, contrary to the preload force of the elastic element 26, which pushes the valve disc 3 towards the first valve seat 12, towards the stationary core 35 in the direction of the axis L, as shown in Fig. 4 to Fig. 6 is shown. As in Fig. Figure 6 shows that when the movable core 40 is displaced in the direction of the axis L, the pair of retaining arms 45 of the movable core 40 is spaced apart from the arm contact surfaces 27, and the valve engagement section 73 of the cap element 70, which is mounted between the retaining arms 45, engages with the engagement surface 4 of the valve disc 3. The valve disc 3, which rests on the first valve seat 12, is displaced to the second valve seat 13, with the guide grooves 3a being supported by the retaining arms 45.

[0063] As described above, a gap G is formed between the attack section 4 of the valve disc 3 and the valve engagement section 73 of the cap element 70. When the excitation coil 32 is switched to the energized state, instead of the valve disc 3 moving towards the second valve seat 13, the gap G between the attack section 4 and the valve engagement section 73 is initially compressed (contracted) simultaneously with the movement of the movable core 40. After the gap G has been reduced to zero, the valve engagement section 73 comes into contact with the attack section 4 of the valve disc 3, and the valve disc 3 moves towards the second valve seat 13.

[0064] By attracting the movable core 40, the valve disc 3 is placed on the second valve seat 13 to close the outlet opening 21 and to expose the first valve seat 12, which faces the second valve seat 13. Accordingly, the supply port P communicates with the outlet port A through the supply opening 15 and the valve body 11, and the pressurized fluid supplied by the supply port P is discharged through the outlet port A (see figure). Fig. 4 to Fig. 6) Here, the valve engagement section 73 of the cap element 70, which is arranged on the pair of retaining elements 45, is formed by a thin plate that is elastic in the direction of the axis L. When the valve disc 3 contacts the second valve seat 13, the force exerted on the valve disc 3 in the direction of the axis L can be absorbed by the valve engagement section 73. This design can prevent the valve disc 3 from wearing down or becoming irreversibly deformed (permanently deformed) when such a force is repeatedly applied to the valve disc 3.

[0065] When the excitation coil 32 is no longer energized and switches to the demagnetized state, as described in the Fig. 1, Fig. 2 to Fig.As shown in Figure 3, the movable core 40 is spaced apart from the stationary core 35, and the valve disc 3 is lifted from the second valve seat 13 by the preload force of the elastic element 26. As described above, the valve disc 3 closes the first valve seat 12 and exposes the second valve seat 13, so that the outlet port A communicates with the exhaust port R through the valve body 11 and is exposed to the environment. At this time, the flat free end faces of the pair of retaining arms 45 rest against the pair of arm contact surfaces 27, which are parallel to the free end faces 46, so that the movable core 40 is accurately positioned relative to the valve body 10. This further controls the response behavior of the solenoid valve.

[0066] When the free end faces 46 of the retaining arms 45 rest against the arm contact surfaces 27, the valve disc 3 is placed on the first valve seat 12, forming the gap G between the attack section 4 facing the first valve seat 12 and the valve engagement section 73 of the cap element 70. This design prevents the kinetic energy of the movable core 40 from being directly transferred to the valve disc 3 when the valve disc 3 is placed on the first valve seat 12, thereby reducing the external force applied to the valve disc 3 in the direction of the axis L. This prevents the valve disc 3 from wearing down or becoming irreversibly deformed (permanently deformed) when such an external force is repeatedly applied to it. Thus, a change in the dimensions of the valve disc 3 in the direction of the axis L over time is prevented.

[0067] Accordingly, changes in the stroke of the movable core 40, i.e., the distance from the first valve seat 12 to the valve disc 3, can be prevented. Thus, variations in the flow rate of the fluid flowing through the valve seat 12 or in the response behavior of the solenoid valve can be avoided as far as possible.

[0068] As described above, the solenoid valve 1 according to the present invention can reduce the number of components and simplify the structure and shape of the movable core 40 by seamlessly integrating the iron core 43 and the valve retention section of the movable core 40. This design can thus reduce manufacturing costs.

[0069] So far, an electromagnetic valve according to the present invention has been described. However, the invention of the present application is not limited to the above embodiment and its design can of course be modified in many respects within the scope of protection without departing from the scope of the claims.

[0070] Although the above example describes a three-way solenoid valve, the number of connections is not limited to this and can also be two. Reference symbol list 1 solenoid valve 3 Valve disc 3a Guide groove 4 Attack Section 7 Magnetic section 10 valve bodies 11 Valve box 12 first valve seat 13 second valve seat 14 floor wall area 26 elastic element 27 Arm contact area 40 movable core 43 Iron core 43a End area 45 Retaining arm (valve retaining section) 47 locking hooks 50 surface 51 Side end area 60 coil bodies 60a central hole 61 first inner surface Section 62 63 middle section 64th step section 65 second inner surface 66 convex thread 67 projecting intervention wall 70 cap element 71 Access opening 72 Valve opening 73 Valve intervention section 80 magnetic ring 81 Intervention hole section A Output port P Supply connection R outlet connection

Claims

[1] An electromagnetic valve (1) with: a movable core (40) having a first end on one side in an axial direction (L) and a second end on the other side in the axial direction (L), wherein the movable core (40) moves in response to an excitation of an electromagnet in the axial direction (L), a valve body (10) with a plurality of ports (A, P, R) into or from which a pressure fluid flows, and a valve box (11) with which the ports (A, P, R) are connected, and a valve disc (3) which is received in the valve box (11), wherein the valve disc (3) moves towards and away from a valve seat (12) in the valve box (11) in accordance with the displacement of the movable core in the axial direction (L) in order to change connection states between the ports (A, P, R), wherein the movable core (40) comprises an iron core (43) which is located closer to the first end and is formed into a plate with a substantially rectangular cross-section, and a valve holding section (45) which is located closer to the second end and merges into the iron core (43), wherein both surfaces of the movable core (40), which are oriented in a thickness direction, are single, flat, parallel surfaces and extend continuously from the iron core (43) to the pair of retaining arms (45), and wherein the valve disc (3) is held between the pair of retaining arms (45) characterized by , that the valve retaining section (45) has a pair of retaining arms (45) and wherein the pair of retaining arms (45) are arranged side by side in a width direction of the movable core (40) such that they are parallel to each other and integrally formed with the iron core (43). [2] The solenoid valve (1) according to claim 1, wherein the valve disc (3) is held between the pair of retaining arms (45) such that it can move relative to the retaining arms (45) in the axial direction (L), wherein an elastic element (26) is arranged in the valve box (11), wherein the elastic element (26) pushes the valve disc (3) towards the valve seat (12) to cause the valve disc (3) to seat on the valve seat (12), and wherein the pair of retaining arms (45) each has a valve engagement section (73) which engages with an attack section (4) of the valve disc (3) which sits on the valve seat (12) when the movable core (40) moves in a direction opposite to the direction in which the elastic element (26) pushes the valve disc (3) and lifts the valve disc (3) away from the valve seat (12) against a preload force of the elastic element (26). [3] The solenoid valve (1) according to claim 2, wherein when the valve disc (3) is placed on the valve seat (12) by the elastic element (26), when the movable core (40) moves in the direction in which the elastic element (26) pushes the valve disc (3), the valve engagement section (73) is not in contact with the valve disc (3). [4] The solenoid valve (1) according to claim 3, wherein the valve seat (12) is provided on a bottom wall surface (14) of the valve box (11) which faces the second end of the movable core (40), wherein free end faces of the support arms (45) are flat surfaces perpendicular to an axis (L), wherein the bottom wall surface (14) has an arm contact surface (27), wherein the arm contact surface (27) is a flat surface parallel to the free end surfaces of the retaining arms (45), and wherein the free end surfaces move towards and away from the arm contact surface (27) according to a displacement of the movable core (40), and wherein, when the valve disc (3) rests on the valve seat (12), when the movable core (40) is moved to the second end, the free end surfaces of the retaining arms (45) rest against the arm contact surfaces (27) and a gap (G) with a dimension in the axial direction (L) that is smaller than a stroke of the movable core (40) is formed between the valve engagement section (73) and the attack section (4) of the valve disc (3). [5] The solenoid valve (1) according to claim 2, wherein the valve seat (12) is a first valve seat (12) formed on the bottom wall surface (14) of the valve box (11), and a second valve seat (13) provided in the valve box (11) at a position facing the first valve seat (12) along the axis (L), wherein the valve disc (3) is provided between the first valve seat (12) and the second valve seat (13) and is continuously pressed towards the first valve seat (12) by the elastic element (26), and wherein the valve engagement section (73) on the pair of retaining arms (45) is formed by a thin plate which is elastic in the axial direction (L), and wherein the valve engagement section (73) engages with the engagement section (4) of the valve disk (3) seated on the first valve seat (12) when the movable core (40) moves from the second end to the first end, and the valve disk (3) lifts off the first valve seat (12) against a preload force of the elastic element (26) to cause the valve disk (3) to seat on the second valve seat (13). [6] The solenoid valve (1) according to claim 5, wherein the pair of retaining arms (45) has engagement hooks (47) at free end sections which project away from each other in one direction, wherein a cap element (70) formed from a thin metal plate with an essentially U-shaped cross-section is attached between the free end sections of the pair of retaining arms (45) and the cap element (70) has a pair of engagement openings (71) which engage with the engagement hooks (47) of the pair of retaining arms (45), and a valve opening (72) formed between the pair of engagement openings (71) and which allows the valve disc (3) to be placed on the first valve seat (12) through the valve opening, wherein the valve engagement section (73) is provided on a circumferential section of the valve opening (72), and wherein the attack section (4) is provided on an end face of the valve disc (3) which faces the first valve seat (12). [7] The solenoid valve (1) according to claim 2, wherein the valve disc (3) has a pair of guide grooves (3a) opening in opposite directions and extending in the axial direction (L), wherein the pair of retaining arms (45) is inserted into the pair of guide grooves (3a) such that they are movable relative to each other in the axial direction (L), and wherein the valve disc (3) is held by the pair of retaining arms (45) such that it can slide in the axial direction (L). [8] The solenoid valve (1) according to claim 7, wherein the valve seat (12) is provided on a bottom wall surface (14) of the valve box (11) which faces the second end of the movable core (40), wherein the pair of retaining arms (45) has engagement hooks (47) that project in directions away from each other, wherein a cap element (70) formed from a thin metal plate with an substantially U-shaped cross-section is arranged between free end sections of the pair of retaining arms (45) and wherein the cap element (70) has a pair of engagement openings (71) which engage with the engagement hooks (47) of the pair of retaining arms (45), and a valve opening (72) formed between the pair of engagement openings (71) and through which the valve opening (72) allows the valve disc (3) to be placed on the first valve seat (12), and wherein the valve engagement section (73) is provided on a circumferential section of the valve opening (72) and wherein the valve engagement section (73) engages with an end face of the valve disk (3) facing the valve seat (12) when the movable core (40) moves from the second end to the first end. [9] The solenoid valve (1) according to claim 1, wherein the solenoid valve (1) has a magnetic section (7) and the magnetic section (7) comprises a coil former (60) and a magnetic ring (80), wherein the coil former (60) has a central hole (60a) in which an iron core (43) of the movable core (40) is inserted such that it can slide in the axial direction (L), wherein the coil former (60) comprises a coil wound around an outer circumference of the coil former (60), wherein the magnetic ring (80) is arranged such that it surrounds an opening of the central hole (60a) at an end of the coil former (60) which is closer to the valve body (10), wherein the central hole (60a) of the coil former (60) has a substantially rectangular cross-section and a pair of first inner surfaces (61) and a pair of second inner surfaces (65), wherein the pair of first inner surfaces (61) faces a pair of surfaces (50) of the iron core (43) parallel to each other and on both sides in a thickness direction of the iron core (43), and wherein the pair of second inner surfaces (65) faces a pair of end faces (51) of the iron core (43) parallel to each other and on both ends in a width direction of the iron core (43), wherein step sections (64) are provided on both end sections of the pair of first inner surfaces (61) in a width direction of the first inner surfaces (61) to shorten a distance between the first inner surfaces (61) such that it is shorter than a distance between middle sections (63),wherein the step sections (64) transition into the second inner surfaces (65) and wherein a pair of convex threads (66) extending in the axial direction (L) is provided on the pair of second inner surfaces (65), and, wherein the pair of side end faces (51) of the iron core (43) is held by the pair of convex threads (66) so that they can slide in the axial direction (L), wherein the pair of surfaces (50) of the iron core (43) is held by the step sections (64) so ​​that they can slide in the axial direction (L), and wherein the iron core (43) extends through the magnetic ring (80) and its free end projects towards the valve body (10). [10] The solenoid valve (1) according to claim 9, wherein a pair of projecting engagement walls (67) extending in the axial direction (L) from the pair of second inner surfaces (65) is provided at the opening of the central hole (60a), and wherein the magnetic ring (80) has an engagement hole section (81) in which the projecting engagement walls (67) are inserted, and wherein the magnetic ring (80) is positioned coaxially to the coil body (60) by the fact that the projecting engagement walls (67) are inserted into the engagement hole section (81).

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