Solenoid valve

Abstract

Provided is a solenoid valve that has low flow path resistance.　A solenoid valve 1 comprises a driving unit 20 that includes a coil 21, a fixed iron core 22, and a movable iron core 23 and a valve body 30 that uses the driving unit 20 so as to adjust the degree of opening of a flow path 15, wherein: the movable iron core 23 is provided so as to be rotatable with respect to a rotation axis 17 by energizing the coil 21; the coil 21 is disposed in such a manner as to surround the rotation axis 17; and the rotation of the movable iron core 23 causes the valve body 30 to move in a direction that crosses the flow path 15.

Description

solenoid valve

[0001] The present invention relates to a solenoid valve, for example, a solenoid valve that opens and closes a flow path through which a fluid flows or switches the flow path.

[0002] In various industrial fields, fluid circuits are used in which a fluid supply source and a fluid load such as a fluid actuator or a heat exchanger are connected by a flow path. Some of these fluid circuits are provided with solenoid valves for opening and closing the flow path or for switching between flow paths.

[0003] For example, the solenoid valve disclosed in Patent Document 1 includes a drive unit having a coil, a main valve element that adjusts the opening of a flow path in response to drive of the drive unit, and a housing. The drive unit is primarily composed of a coil, a plunger, an attractor, and a spring. The attractor is magnetized when current is applied to the coil and attracts the plunger. As the plunger moves, the main valve element moves away from the valve seat in the housing, opening the flow path. This allows fluid to pass from below the main valve element to the side. Furthermore, when current is stopped from passing through the coil, the spring moves the plunger together with the main valve element in the return direction, causing the main valve element to contact the valve seat in the housing and close the flow path.

[0004] JP 2019-7572 A (pages 6 and 7, Figure 1)

[0005] In the solenoid valve of Patent Document 1, a part of the flow path near the main valve body needs to be perpendicular to the main valve body and extend in the direction of movement of the main valve body. As a result, when the flow path is opened, the fluid changes direction near the main valve body, which causes a problem of high flow path resistance and a tendency for pressure loss to occur.

[0006] The present invention has been made in view of these problems, and has as its object to provide a solenoid valve with low flow resistance.

[0007] In order to solve the above problems, the solenoid valve of the present invention is a solenoid valve comprising: a drive unit having a coil, a fixed iron core, and a movable iron core; and a valve element that adjusts the opening of a flow path by the drive unit, wherein the movable iron core is rotatable about a rotation axis when current is applied to the coil, the coil is arranged to surround the rotation axis, and the valve element moves in a direction across the flow path as the movable iron core rotates. In this way, not only is the coil arranged to surround the rotation axis, but the valve element moves in a direction across the flow path, making it possible to form a flow path with low flow resistance.

[0008] The fixed core may be provided at a portion of the circumferential direction of the coil, whereby the stopping position of the movable core can be determined by adjusting the position of the fixed core.

[0009] The fixed core may be provided along the outer periphery of a housing that accommodates the movable core, which facilitates assembly because the coil and the movable core can be assembled separately from the housing.

[0010] The coils may be arranged in two stages in the axial direction, whereby the magnetic force can be switched by switching the coils to be energized.

[0011] The coils may be arranged in two stages in the axial direction, and the fixed cores may be arranged at positions where the coils are in different phases in the circumferential direction. In this way, forward rotation control and reverse rotation control can be reliably performed by switching the coils to be energized.

[0012] The fixed core may be arc-shaped, which makes the distance between the fixed core and the movable core substantially constant, thereby allowing a magnetic force to be applied to the movable core efficiently.

[0013] The movable core may have an arc shape along the fixed core, which allows a magnetic force to be applied to the movable core more efficiently.

[0014] FIG. 1 is a top view showing an open state of a solenoid valve according to a first embodiment of the present invention. (a) is a cross-sectional view taken along line A-A in FIG. 1 , and (b) is a cross-sectional view taken along line B-B in FIG. 1 . FIG. 2 is a top view showing a closed state of the solenoid valve according to the first embodiment. (a) is a top view showing a solenoid valve according to a second embodiment of the present invention, and (b) is a cross-sectional view taken along line C-C in (a) . FIG. 3 is a top view showing a closed state of the solenoid valve according to the second embodiment. (b) is a top view showing a solenoid valve according to a third embodiment of the present invention. (c) is a top view showing a solenoid valve according to a fourth embodiment of the present invention. (d) is a top view showing an example of another shape of the outer diameter side end of the movable core.

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A solenoid valve according to the present invention will be described below with reference to the following examples.

[0016] A solenoid valve according to a first embodiment will be described with reference to Figures 1 to 3. In the following description, the top and bottom of Figure 2 will be taken as the top and bottom of the solenoid valve.

[0017] As shown in FIGS. 1 and 2, a solenoid valve 1 of the present invention is used to open and close a fluid circuit.

[0018] The solenoid valve 1 is mainly composed of a housing 10 , a solenoid 20 as a drive unit, and a valve body 30 .

[0019] The housing 10 is mainly composed of a cap 11 and a case 12. The cap 11 and the case 12 are made of non-magnetic stainless steel. In Figures 1 and 3, the cap 11 is shown by a two-dot chain line to clearly show the valve body 30 and other components. The cap 11 and the case 12 may be made of resin, or may be made of any other non-magnetic material as appropriate.

[0020] Referring to Figure 2, the cap 11 is fixed by having the male threads on the side of a cylindrical male thread portion that extends axially downward from the radial center of the disk and is screwed into the female threads formed on the inner periphery of the case 12.

[0021] A communication passage 11a is formed in the cap 11, linearly penetrating a portion of the cap 11 between its radial center and its radially outer edge in the axial direction. The upper opening of the communication passage 11a is an inlet port P1 through which the fluid flows in.

[0022] Furthermore, the communication passage 11a is formed so as to substantially coincide with the axis of a communication passage 15, which will be described later, when the cap 11 is fixed to the case 12.

[0023] An O-ring 50 is provided as a sealing member between the cap 11 and the case 12. This more reliably seals the gap between the cap 11 and the case 12, preventing fluid leakage. Note that the sealing member is not limited to the O-ring 50 and may be changed as appropriate to a gasket or the like.

[0024] The cap 11 also has a recess 11c that is circular in bottom view and located at the center of the diameter of its lower portion. The recess 11c is recessed axially upward from the lower end surface 11b of the cap 11 and opens axially downward. The upper portion of the tension spring 18 is fixed to the recess 11c. The lower portion of the tension spring 18 is fixed to a shaft portion 27 of the movable core 23, which will be described later. For ease of understanding, the movable core 23 is indicated by a dot.

[0025] The case 12 includes a base 13 extending in the axial direction, and a cylindrical peripheral wall 14 extending axially upward from the outer diameter side edge of the base 13 .

[0026] The base 13 is connected to an extension 13a extending axially downward from a portion between the radial center and the radial outer edge thereof.

[0027] 2(a), a communication passage 15 is formed in the base 13, penetrating linearly along the center of the extension 13a from the lower end of the extension 13a to the upper end of the base 13. The lower opening of the communication passage 15 is an outlet port P2 through which the fluid flows out.

[0028] When the cap 11 is fixed to the case 12, the upper end surface 13b of the base 13 is located lower than the lower end surface 11b of the cap 11. In other words, a space S is left between the lower end surface 11b of the cap 11 and the upper end surface 13b of the base 13. The communication passage 11a in the cap 11 and the communication passage 15 in the case 12 communicate with the space S.

[0029] 1, the gray painted portion of the upper end surface 13b of the base 13 surrounding the communication passage 15 is the valve seat 31 in this embodiment. The valve seat 31 and the valve element 30 form a valve 40.

[0030] A groove 16 having a shape of a roughly one-third arc in top view is formed at the outer diameter end of the base 13. The groove 16 is recessed axially downward from the upper end surface 13b and opens axially upward. The groove 16 extends from roughly the 7 o'clock direction to roughly the 11 o'clock direction in top view. Furthermore, the vertical dimension, i.e., the depth dimension, of the groove 16 is roughly the same as the axial dimension of two coils 21U and 21D, which will be described later (see FIG. 2).

[0031] 2, a recess 13c that is circular in top view is formed in the upper part of the base 13. The recess 13c is recessed axially downward from the upper end surface 13b in the radial center of the base 13 and is open axially upward. A rotation shaft 17 is fixed on the axis of the recess 13c in the radial center.

[0032] The axis of the rotary shaft 17 is substantially parallel to the axis of the communication passages 11 a and 15 .

[0033] The peripheral wall 14 has an internally threaded portion formed on the inside at its axial upper end, where the above-mentioned internal thread is formed.

[0034] The solenoid 20 is mainly composed of two tiers of coils 21U and 21D, one above the other, wound around the rotating shaft 17, the other at the center, and surrounding the rotating shaft 17, a fixed iron core 22 arranged to surround the rotating shaft 17, and a movable iron core 23 arranged inside the housing 10.

[0035] 2, the upper coil 21U is wound around an annular bobbin 21a. The bobbin 21a is fitted around and fixed to the housing 10. The coil 21U may be wound directly around the fixed core 22 without the bobbin 21a, or may be wound in a different manner as appropriate. The same applies to the coil 21D.

[0036] The lower coil 21D is wound around an annular bobbin 21b, which is separate from the upper bobbin 21a and is fixed to the housing 10 below the bobbin 21a.

[0037] For convenience of explanation, direct illustration is omitted, but the coils 21U, 21D, bobbins 21a, 21b, and fixed core 22 are molded together with the case 12 while the case 12 is inserted into the housing 10, thereby forming them into one unit with the case 12.

[0038] In addition, at least one of coils 21U, 21D, bobbins 21a, 21b, and fixed iron core 22 may be fixed to case 12 by adhesive or welding, and at least one of coils 21U, 21D, bobbins 21a, 21b, and fixed iron core 22 may be integrated with coil 21 in whole or in part by molding.

[0039] 2, the stator core 22 includes an annular yoke 24, an upper outer diameter side yoke piece 25, and a lower outer diameter side yoke piece 26. The stator core 22 is made of steel, i.e., a magnetic material. However, the stator core 22 may be made of iron, or may be made of any other magnetic material as appropriate.

[0040] The annular yoke 24 has an annular plate portion 24a having an annular plate shape, an upward piece 24b (see FIG. 2(a)) extending upward generally perpendicular to a portion of the circumferential direction of the inner diameter edge of the annular plate portion 24a, and a downward piece 24c (see FIG. 2(b)) extending downward generally perpendicular to another portion of the circumferential direction of the inner diameter edge of the annular plate portion 24a. In other words, the upward piece 24b and the downward piece 24c are located at positions out of phase with each other in the circumferential direction. The upward piece 24b and the downward piece 24c are each arranged over a portion of approximately 60 degrees when viewed from above.

[0041] The annular plate portion 24a is disposed axially between the upper bobbin 21a and the lower bobbin 21b.

[0042] As shown in FIG. 2A, the upward piece 24b is disposed along the inner peripheral surface of the upper bobbin 21a.

[0043] As shown in FIG. 2B, the downward piece 24c is disposed along the inner peripheral surface of the lower bobbin 21b.

[0044] 1, the outer diameter side yoke piece 25 on the upper stage is curved along the outer peripheral surface of the upper stage bobbin 21a. The outer diameter side yoke piece 25 on the upper stage is arranged from approximately 9:30 to approximately 11:30 in a top view, i.e., over an approximately 60-degree portion.

[0045] As shown in FIG. 2( a), the outer diameter side yoke piece 25 on the upper side has a cross section formed in an upside-down L shape, and has a radial plate-like portion 25 a extending radially and an axial plate-like portion 25 b extending downward substantially perpendicular to the outer diameter edge of the radial plate-like portion 25 a.

[0046] The axial plate portion 25b of the upper outer diameter yoke piece 25 is fixed to the outer diameter end of the annular plate portion 24a. The radial plate portion 25a of the upper outer diameter yoke piece 25 is disposed along the upper end surface of the upper bobbin 21a, and the axial plate portion 25b is disposed along the outer peripheral surface of the upper bobbin 21a.

[0047] The outer diameter side yoke piece 25 on the upper stage, together with the annular plate portion 24a and the upward piece portion 24b of the annular yoke 24, surrounds the portion of the upper stage coil 21U located from approximately 9:30 to approximately 11:30 when viewed from above.

[0048] 1 and 2, the lower-stage outer yoke piece 26 is curved along the outer peripheral surface of the lower-stage bobbin 21b. The lower-stage outer yoke piece 26 is disposed from approximately 6:30 to approximately 8:30 in a top view. In FIG. 1, the upper-stage bobbin 21a and the lower-stage bobbin 21b have approximately the same shape and are disposed approximately coaxially.

[0049] As shown in FIG. 2( b), the outer diameter side yoke piece 26 on the lower side has a cross section formed in a left-right inverted L shape, and has a radial plate-like portion 26 a extending radially and an axial plate-like portion 26 b extending axially upward and generally perpendicular to the outer diameter edge of the radial plate-like portion 26 a.

[0050] The axial plate portion 26b of the lower outer diameter yoke piece 26 is fixed to the outer diameter end of the annular plate portion 24a. The radial plate portion 26a of the lower outer diameter yoke piece 26 is disposed along the lower end surface of the lower bobbin 21b, and the axial plate portion 26b is disposed along the outer peripheral surface of the lower bobbin 21b.

[0051] The lower-stage outer diameter side yoke piece 26, together with the annular plate portion 24a and downward piece portion 24c of the annular yoke 24, surrounds the portion of the lower stage coil 21D located from approximately 6:30 to approximately 8:30 when viewed from above.

[0052] 1 and 2, the movable core 23 includes a shaft portion 27 rotatably fitted onto the rotary shaft 17, arm portions 28 extending radially outward from the shaft portion 27, outer diameter side end portions 29 having a one-sixth circular arc shape in top view extending circumferentially on both sides from the arm portions 28, and a disk-shaped valve body 30 fixed to the shaft portion 27. The movable core 23 is made of steel, i.e., a magnetic material.

[0053] The movable core 23 may be made of iron, a magnet, or any other suitable magnetic material. The movable core 23 only needs to have its outer diameter end 29 made of a magnetic material, and the shaft 27, arm 28, and valve element 30 may be made of a non-magnetic material.

[0054] The shaft portion 27 is formed in a cylindrical shape that extends in the axial direction and has a bottom at its lower side. The bottom of the shaft portion 27 is also penetrated in the axial direction. A bearing 32 is fitted and fixed inside the shaft portion 27.

[0055] The arm portion 28 is formed in the shape of a narrow flat plate, in other words, a strip, and is continuous with the upper end of the shaft portion 27.

[0056] The outer diameter side end portion 29 has a generally one-sixth circular arc shape in top view, and its circumferential center is continuous with the arm portion 28. More specifically, the outer diameter side end portion 29 has a flat horizontal plate portion 29a (see FIG. 1) that is continuous with the arm portion 28 in the horizontal direction, and a curved vertical plate portion 29b (see FIG. 2(a)) that is bent at approximately 90 degrees from the outer diameter end of the horizontal plate portion 29a toward the axially downward side and extends axially downward.

[0057] Referring to FIG. 1, the horizontal plate portion 29 a extends in the circumferential direction along the groove 16 in the housing 10 .

[0058] The vertical plate portion 29b is formed so as to follow the groove 16 in the housing 10, more specifically so as to pass through the radial center of the groove 16, and its outer peripheral surface is located on the inner diameter side of the outer peripheral surface of the groove 16. The vertical plate portion 29b has an inner peripheral surface located on the outer diameter side of the groove 16 in the case 12. In other words, the vertical plate portion 29b is prevented from coming into contact with the outer diameter side peripheral surface or the inner diameter side peripheral surface of the groove 16.

[0059] As shown in FIG. 2, the vertical plate portion 29b is formed so as to overlap the upper coil 21U and the lower coil 21D in the radial direction.

[0060] As shown in FIG. 1, when the valve 40 is in an open state, the valve body 30 is located at approximately the 6 o'clock position in the shaft portion 27 when viewed from above.

[0061] Next, opening and closing of the flow passage by the solenoid valve 1 will be described.

[0062] As shown in FIG. 1, when the outer diameter side end portion 29 is positioned so as to overlap radially with the outer diameter side yoke piece 25 on the upper stage side, the valve body 30 is spaced from the valve seat 31 and the valve 40 is open.

[0063] 2(a), when the valve 40 is in an open state, the fluid that has flowed into the space S from the communication passage 11a in the cap 11 passes through the communication passage 15 in the case 12. Because the communication passage 15 extends linearly in the axial direction, the flow resistance is small and pressure loss is unlikely to occur.

[0064] Furthermore, when fluid continues to flow into the space S from the communication passage 11a, the movable core 23 is pushed axially downward by the fluid pressure, and the arm portion 28 abuts against the upper end surface 13b of the case 12. This prevents the movable core 23 from rotating unintentionally.

[0065] To close the valve 40, first the inflow of fluid is stopped. This reduces the force pressing the movable core 23 downward due to fluid pressure. This force exceeds the elastic return force of the tension spring 18, and as the tension spring 18 elastically returns, the movable core 23 moves axially upward along the pivot shaft 17 and stops below the bottom end surface 11b of the cap 11. This helps to reduce friction generated by contact with the bottom end surface 11b of the cap 11 and the top end surface 13b of the case 12 as the movable core 23 rotates.

[0066] Next, when current begins to flow through the lower-stage coil 21D, magnetic flux is generated. The fixed core 22 forms a magnetic path that collects the magnetic flux generated in the lower-stage coil 21D by the annular plate portion 24a, downward piece 24c, and lower-stage outer diameter side yoke piece 26 of the annular yoke 24. In other words, the annular plate portion 24a, downward piece 24c, and lower-stage outer diameter side yoke piece 26 are primarily magnetized.

[0067] Furthermore, the upward piece 24b and the upper-stage outer diameter side yoke piece 25 are arranged in a different phase in the vertical and circumferential directions from the downward piece 24c and the lower-stage outer diameter side yoke piece 26. As a result, even if the downward piece 24c and the lower-stage outer diameter side yoke piece 26 are magnetized, the upward piece 24b and the upper-stage outer diameter side yoke piece 25 are less likely to be magnetized.

[0068] Also, referring to Figure 2(a), the upper end of the upward piece 24b is spaced apart from the inner diameter end of the radial plate portion 25a of the outer diameter side yoke piece 25 on the upper side, and referring to Figure 2(b), the lower end of the downward piece 24c is spaced apart from the inner diameter end of the radial plate portion 26a of the outer diameter side yoke piece 26 on the lower side.

[0069] As a result, when current is applied to the lower coil 21D, magnetic flux generated between the lower outer diameter side yoke piece 26 and the movable core 23 is less likely to flow from the movable core 23 to the upper outer diameter side yoke piece 25. As a result, even if the downward piece 24c and the lower outer diameter side yoke piece 26 are magnetized, the upward piece 24b and the upper outer diameter side yoke piece 25 are less likely to be magnetized.

[0070] As a result, the outer end 29 is attracted to the lower outer yoke piece 26 and moves counterclockwise when viewed from above. Accordingly, the movable core 23 rotates about the rotation shaft 17 counterclockwise when viewed from above.

[0071] The rotation of the movable core 23 is stopped when the end 29c of the outer diameter side end 29 on the counterclockwise side in top view abuts against the side surface 16a of the groove 16 on the counterclockwise side in top view. As the movable core 23 rotates, the valve element 30 moves counterclockwise in top view and stops at a position where it overlaps with the valve seat 31 in the axial direction (see FIG. 3).

[0072] Thereafter, when fluid flows into the space S from the communication passage 11a, the movable core 23 is pushed axially downward by the fluid pressure, and the valve element 30 is seated on the valve seat 31. This closes the valve 40 (see FIG. 3). In addition, the movable core 23 is prevented from unintentionally rotating and opening the valve 40.

[0073] To open the valve 40, the inflow of fluid is first stopped. When the power supply to the lower coil 21D is stopped and the power supply to the upper coil 21U is started from the state shown in Figure 3, magnetic flux is generated. The fixed core 22 forms a magnetic path that collects the magnetic flux generated in the upper coil 21U by the annular plate portion 24a, upward piece 24b, and upper outer diameter yoke piece 25 of the annular yoke 24. In other words, the annular plate portion 24a, upward piece 24b, and upper outer diameter yoke piece 25 are primarily magnetized.

[0074] Furthermore, the downward piece 24c and the lower-stage outer diameter side yoke piece 26 are arranged in a different phase in the vertical and circumferential directions from the upward piece 24b and the upper-stage outer diameter side yoke piece 25. As a result, even if the upward piece 24b and the upper-stage outer diameter side yoke piece 25 are magnetized, the downward piece 24c and the lower-stage outer diameter side yoke piece 26 are less likely to be magnetized.

[0075] As described above, the upper end of the upward piece 24b is spaced apart from the inner diameter end of the radial plate portion 25a of the outer diameter side yoke piece 25 on the upper side (see FIG. 2(a)), and the lower end of the downward piece 24c is spaced apart from the inner diameter end of the radial plate portion 26a of the outer diameter side yoke piece 26 on the lower side (see FIG. 2(b)).

[0076] This makes it difficult for magnetic flux generated between the upper-stage outer diameter side yoke piece 25 and the movable core 23 when current is applied to the upper-stage coil 21U to flow from the movable core 23 to the lower-stage outer diameter side yoke piece 26. As a result, even if the upward-facing piece 24b and the upper-stage outer diameter side yoke piece 25 are magnetized, the downward-facing piece 24c and the lower-stage outer diameter side yoke piece 26 are less likely to be magnetized.

[0077] As a result, the outer end 29 is attracted to the upper outer yoke piece 25 and moves clockwise in top view, causing the movable core 23 to rotate clockwise around the rotation shaft 17 in top view.

[0078] The rotation of the movable core 23 is stopped when the end 29d of the outer diameter side end 29 on the clockwise side in top view abuts against the side surface 16b of the groove 16 on the clockwise side in top view. As the movable core 23 rotates, the valve element 30 moves in the clockwise direction in top view and leaves the valve seat 31, thereby opening the valve 40 (see FIG. 1).

[0079] After the rotation of the movable iron core 23 has stopped, the current supply to the upper coil 21U and the lower coil 21D may be stopped.

[0080] In addition, although the inflow of fluid is stopped before the movable iron core 23 is rotated, the inflow of fluid does not have to be stopped. In such a configuration, the tension spring 18 may be omitted.

[0081] As described above, in the solenoid valve 1 of this embodiment, the upper coil 21U and the lower coil 21D are arranged to surround the rotary shaft 17. In addition, the valve element 30 moves in a direction crossing the communication passage 15. As a result, the solenoid valve 1 can form a linear communication passage 15 that extends in the axial direction, thereby reducing flow resistance.

[0082] Furthermore, since the communication paths 11a and 15 are arranged in a substantially straight line, the flow path resistance can be further reduced.

[0083] Furthermore, the axes of the communication passages 11a and 15 are substantially parallel to the axis of the rotary shaft 17, which further reduces the flow resistance.

[0084] Furthermore, since the solenoid valve 1 has a space S between the communicating passages 11a and 15, the flow path resistance can be reduced even when the communicating passages 11a and 15 are arranged at different phases in the circumferential direction or when one or more communicating passages other than the communicating passage 11a are formed in the cap 11.

[0085] Furthermore, the fixed core 22 is provided with an annular plate portion 24a, an upward piece 24b, and an upper-stage outer diameter side yoke piece 25 of the annular yoke 24 at a portion of the circumference of the upper-stage coil 21U. Furthermore, the annular plate portion 24a, a downward piece 24c, and a lower-stage outer diameter side yoke piece 26 of the annular yoke 24 are provided at a portion of the circumference of the lower-stage coil 21U. Therefore, the stopping position of the movable core 23 can be determined by adjusting the position of the fixed core 22.

[0086] Furthermore, since the fixed core 22 is provided along the outer periphery of the housing 10, the upper and lower coils 21U and the movable core 23 can be assembled separately from the housing 10. This makes the solenoid valve 1 easy to assemble.

[0087] Furthermore, since the solenoid valve 1 is provided with the upper coil 21U and the lower coil 21D, the magnetic force may be switched by switching between energizing the upper coil 21U and energizing the lower coil 21D. With this configuration, the angle by which the movable iron core 23 is rotated can be changed in accordance with the generated magnetic force, thereby adjusting the opening degree of the valve 40.

[0088] The solenoid valve 1 is also provided with an upper coil 21U and a lower coil 21D, and the upward piece 24b of the annular yoke 24 and the upper outer diameter side yoke piece 25 are arranged in different circumferential phases from the downward piece 24c of the annular yoke 24 and the lower outer diameter side yoke piece 26. As a result, forward rotation control and reverse rotation control can be reliably performed by switching between supplying electricity to the upper coil 21U and the lower coil 21D.

[0089] The annular yoke 24, the upper-stage outer diameter side yoke piece 25, and the lower-stage outer diameter side yoke piece 26 are each formed in an arc shape with ends that curves along the upper-stage coil 21U and the lower-stage coil 21D. Furthermore, since the grooves 16 in the housing 10 are formed along the upper-stage coil 21U and the lower-stage coil 21D, the annular yoke 24, the upper-stage outer diameter side yoke piece 25, and the lower-stage outer diameter side yoke piece 26 are shaped along the rotation direction of the movable core 23. As a result, the distance between the fixed core 22 and the movable core 23 is approximately constant throughout the range in which the movable core 23 rotates, and magnetic force can be efficiently applied to the movable core 23.

[0090] Furthermore, since the outer diameter side end portion 29 of the movable core 23 of the fixed core 22 extends circumferentially along the annular yoke 24, the upper-stage outer diameter side yoke piece 25, and the lower-stage outer diameter side yoke piece 26, magnetic force can be efficiently applied to the movable core 23.

[0091] Furthermore, the fixed core 22 is formed so that the outer diameter side end 29 of the movable core 23 overlaps radially with the upper coil 21U and the lower coil 21D, so that magnetic force can be efficiently applied to the movable core 23 whether current is passed through the upper coil 21U or the lower coil 21D.

[0092] Furthermore, since the valve element 30 is disk-shaped, resistance is less likely to occur when the valve element 30 moves in the circumferential direction, and the torque required to rotate the movable iron core 23 can be reduced.

[0093] Furthermore, since the arm portion 28 is narrow and lightweight, the torque required to rotate the movable iron core 23 can be reduced.

[0094] In addition, since the arm portion 28 is narrow and has a small contact area with the upper end surface 13b of the housing 10, the frictional force generated by contact with the upper end surface 13b is low, and the torque required to rotate the movable iron core 23 can be reduced.

[0095] Furthermore, since the outer diameter side end 29 of the movable core 23 abuts against either of the side surfaces 16a, 16b of the movable core 23, rotation is restricted, and therefore the amount of current supplied to the solenoid 20 can be easily controlled.

[0096] In this embodiment, the rotation of the movable core 23 is restricted by the contact of the movable core 23 with either the side surface 16 a or 16 b of the groove 16, but this is not limiting, and a stopper for restricting the rotation of the movable core 23 may be provided on the housing 10, or other suitable modifications may be made. Also, such a means for restricting the rotation of the movable core 23 may not be provided.

[0097] Furthermore, the fixed core 22 has a structure in which the annular yoke 24 has an upward piece 24b and a downward piece 24c, and further the upper outer diameter side yoke piece 25 and the lower outer diameter side yoke piece 26 share the annular plate portion 24a of the annular yoke 24, so that the structure is simple and can be made compact.

[0098] Furthermore, since the fixed core 22 is formed by integrating the annular yoke 24, the upper outer diameter side yoke piece 25, and the lower outer diameter side yoke piece 26, there is no misalignment of the circumferential positions of the upper outer diameter side yoke piece 25 and the lower outer diameter side yoke piece 26, and the position at which the movable core 23 is magnetically attracted and stops is stable.

[0099] The fixed core 22 may be divided into upper and lower sections and may be separate bodies. For example, in Example 2 described later, the upper outer diameter side yoke piece 25 and the upper inner diameter side yoke piece 124 (see FIG. 4B) may be the upper yoke, and the lower outer diameter side yoke piece and the lower inner diameter side yoke piece may be the lower yoke, although not shown directly in the drawings. These may be modified as appropriate.

[0100] In addition, in this embodiment, the valve body 30 is described as being configured to be seated directly on the valve seat 31, but this is not limited to this, and a gasket may be arranged along the lower end of the valve body 30 or the valve seat 31.

[0101] Furthermore, in this embodiment, one outer diameter side end portion 29 is configured to radially overlap one or the other of the outer diameter side yoke pieces 25, 26 when the valve 40 is in the open or closed state. However, this is not limited to this, and an outer diameter side end portion that radially overlaps with the outer diameter side yoke piece 25 and an outer diameter side end portion that radially overlaps with the outer diameter side yoke piece 26 may be provided.

[0102] Next, a solenoid valve according to a second embodiment will be described with reference to Figures 4 and 5. Note that a description of the same configuration as in the first embodiment will be omitted.

[0103] 4, in the solenoid valve 101 of the second embodiment, the solenoid 120 is mainly composed of a coil 121, a fixed core 122, a movable core 123, and a torsion coil spring 126. In other words, the coil in this embodiment has only one stage.

[0104] The coil 121 is wound around a bobbin 121a.

[0105] As shown in FIG. 4B , the fixed core 122 includes an inner diameter side yoke piece 124 and an outer diameter side yoke piece 25 .

[0106] The inner diameter side yoke piece 124 has a cross section formed in an inverted L shape, and has a radial plate-like portion 124a extending radially and an axial plate-like portion 124b extending axially upward and approximately perpendicular to the inner diameter end edge of the radial plate-like portion 124a.

[0107] The radial plate portion 124a of the inner diameter side yoke piece 124 is disposed along the lower end surface of the bobbin 121a, and the axial plate portion 124b is disposed along the inner peripheral surface of the lower bobbin 121a. The inner diameter side yoke piece 124 is disposed over an area of ​​approximately 60 degrees when viewed from above.

[0108] The movable core 123 is formed so that the vertical plate portion 129b at the outer diameter side end portion 129 radially overlaps the coil 121. The depth of the groove 116 in the housing 110 is also matched to the vertical dimension of the vertical plate portion 129b.

[0109] The spring 126 is disposed on a step 113d that is one-third of a circle when viewed from above and is formed on the upper part of the base 113 of the case 112 in the housing 110. The step 113d is recessed axially downward from the upper end face 113b that is on the outer diameter side of the recess 13c, and is open axially upward and toward the outer diameter side.

[0110] 4A, the step 113d has a side wall 113e on the counterclockwise side in a top view and a side wall 113f on the clockwise side in a top view. The communication passage 15 is formed on the clockwise side of the side wall 113f in a top view.

[0111] Further, a shaft 119 is fixed to the step portion 113d at the center of the corner formed by the side walls 113e and 113f. A coil of a spring 126 is fitted onto the shaft 119. The spring 126 is a so-called return spring.

[0112] The arm 126a of the spring 126 located on the counterclockwise side in top view is fixed to an end 129c of the vertical plate portion 129b on the counterclockwise side in top view (see FIG. 4B). The arm of the spring 126 located on the counterclockwise side in top view is fixed to a side wall 113f of the step portion 113d on the clockwise side in top view.

[0113] Furthermore, the spring 126 disposed on the step 113d is located below the upper end surface 113b of the base 113, and is prevented from coming into contact with the movable iron core 123 when the movable iron core 123 rotates. Furthermore, the step 113d is a location where fluid flow is unlikely to occur, and the spring 126 is unlikely to obstruct the flow of fluid.

[0114] 4B, the cap 111 of the housing 110 does not have a recess 11c formed therein, unlike the cap 11 of the first embodiment. The tension spring 18 is also omitted.

[0115] 4(b), when the movable core 123 is supported by the rotary shaft 17, the arm 28 is placed on the upper end surface 113b of the case 112. The movable core 123 is also disposed below the lower end surface 111b of the cap 11 to prevent contact with the lower end surface 111b.

[0116] When the electromagnetic force generated by energizing the coil 121 exceeds the biasing force of the spring 126, the outer diameter side end portion 129 is attracted toward the outer diameter side yoke piece 25, and the valve 40 is opened (see FIG. 4A).

[0117] When the supply of current to the coil 121 is stopped, the biasing force of the spring 126 moves the outer diameter side end 129 counterclockwise in top view. Accordingly, the movable core 123 rotates counterclockwise in top view around the rotation shaft 17. When the counterclockwise end 129c of the outer diameter side end 129 in top view abuts against the side surface 116a of the groove 116, the rotation of the movable core 23 stops. As the movable core 123 rotates, the valve element 30 moves counterclockwise in top view and seats on the valve seat 31, thereby closing the valve 40 (see FIG. 5 ).

[0118] The solenoid valve 101 in this embodiment is of a normally closed type in which the valve 40 is closed when the coil 121 is not energized, but is not limited to this and may be of a normally open type.

[0119] Furthermore, the method of returning the movable iron core 123 by de-energizing is not limited to the structure in which the torsion coil spring 126 is placed in the step portion 113d of the housing 10, but may also be, for example, a single spiral spring fixed across the recess 113c of the housing 10 and the shaft portion 27 of the movable iron core 123, or may be modified as appropriate.

[0120] Next, a solenoid valve according to a third embodiment will be described with reference to Fig. 6. Note that the configuration is the same as that of the second embodiment, and therefore a description of the configuration that overlaps with the second embodiment will be omitted.

[0121] As shown in FIG. 6 , in the solenoid valve 201 of the third embodiment, the movable iron core 223 of the solenoid 220 includes a shaft portion 27, an arm portion 28, a cylindrical outer diameter side end portion 229 extending circumferentially from the outer diameter end of the arm portion 28, and a valve body 30.

[0122] The outer diameter side end portion 229 is composed of a first circumferential extension portion 229a made of a magnetic material and a second circumferential extension portion 229s made of a non-magnetic material. The first circumferential extension portion 229a and the second circumferential extension portion 229s have substantially the same shape as the outer diameter side end portion 129 of the second embodiment.

[0123] The groove 216 in the housing 210 is annular and can accommodate the cylindrical outer diameter side end 229 .

[0124] As a result, only the first circumferential extension portion 229a of the movable iron core 223 is attracted by the electromagnetic force generated by energizing the coil 121, so that the movable iron core 223 can be rotated in the same manner as in the second embodiment.

[0125] Furthermore, since the outer diameter side end portion 229 is cylindrical and continues without interruption in the circumferential direction, it has better strength than the outer diameter side end portion 129 of the second embodiment, which is formed in the shape of a one-sixth of a circle.

[0126] Furthermore, since the outer diameter side end 229 is cylindrical and continues without interruption in the circumferential direction, weight imbalance at various points in the circumferential direction is less likely to occur, i.e., the weight balance is better, compared to the outer diameter side end 129 formed in the shape of a one-sixth circle in the second embodiment. Therefore, the movable iron core 223 can rotate smoothly around the rotation shaft 17.

[0127] Next, a solenoid valve according to a fourth embodiment will be described with reference to Fig. 7. Note that the configuration is the same as that of the second embodiment, and therefore a description of the configuration that overlaps with the second embodiment will be omitted.

[0128] As shown in FIG. 7, in the solenoid valve 301 of the fourth embodiment, the communication passages 15 and 315 are formed concentrically in the housing 310.

[0129] As a result, when the solenoid 120 is energized, the valve element 30 closes the communication passage 315 and opens the communication passage 15. Although not shown directly, when the solenoid 20 is not energized, the valve element 30 closes the communication passage 15 and opens the communication passage 315. In other words, the solenoid valve 301 is a selector valve. The number of communication passages may be changed as appropriate.

[0130] Furthermore, since the solenoid valve 301 has a space S (see FIG. 4(b)) between the communication passage 11a (see FIG. 4(b)) and the communication passages 15 and 315, the flow path resistance can be reduced whether the communication passage 11a is connected to the communication passage 15 or whether the communication passage 11a is connected to the communication passage 315.

[0131] Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention also includes modifications and additions that do not deviate from the gist of the present invention.

[0132] For example, in Examples 1 to 4, the communicating passage formed in the housing is described as extending linearly and approximately parallel to the rotation axis, but this is not limited to this. The communicating passage may be inclined or curved relative to the rotation axis as long as the shape of the flow path is not such that it increases flow path resistance, such as by bending the flow path.

[0133] In addition, in the first embodiment, the fixed core is described as being composed of an annular yoke and one or more yoke pieces, but this is not limited thereto, and the fixed core may be provided at least at the stop position of the movable core, and may be modified as appropriate. Similarly, in the second to fourth embodiments, the fixed core is described as being composed of an inner diameter yoke and an outer diameter yoke, but this is not limited thereto, and the fixed core may be provided at least at the stop position of the movable core, and may be modified as appropriate.

[0134] In addition, in the first to fourth embodiments, the outer diameter side end of the movable core has been described as being arc-shaped or cylindrical, but this is not limited to this, and the outer diameter side end that is attracted to the fixed core does not have to be arc-shaped, as in outer diameter side end 429 shown in Fig. 8, and this part may be approximately the same as the circumferential width of the arm portion, and the shape of the outer diameter side end may be changed as appropriate. Furthermore, the movable core may consist of only the arm portion.

[0135] Furthermore, in Examples 1 to 4, the arm portion of the movable core is described as being narrow and rectangular when viewed from above, but this is not limited to this and may be fan-shaped with a diameter that increases as it moves away from the shaft portion, and the shape may be changed as appropriate.

[0136] Furthermore, in the above-described Examples 1 to 4, the movable iron core has been described as having a vertical plate portion extending axially downward, but this is not limited to this, and the vertical plate portion may extend axially upward, or the vertical plate portion may extend axially upward and downward, respectively, and may be modified as appropriate.

[0137] REFERENCE SIGNS LIST 1 solenoid valve 10 housing 17 rotating shaft 20 solenoid 21D lower coil 21U upper coil 22 fixed core 23 movable core 30 valve body 31 valve seat 40 valve 101 solenoid valve 110 housing 120 solenoid 121 coil 122 fixed core 123 movable core 201 solenoid valve 210 housing 220 solenoid 223 movable core 301 solenoid valve 310 housing 315 communicating passage P1 inlet port P2 outlet port S space

Claims

1. A solenoid valve comprising: a drive unit having a coil, a fixed iron core, and a movable iron core; and a valve body that adjusts the opening of a flow path by the drive unit, wherein the movable iron core is rotatable about a rotation axis when electricity is passed through the coil, the coil is disposed so as to surround the rotation axis, and the valve body moves in a direction crossing the flow path as the movable iron core rotates.

2. A solenoid valve as set forth in claim 1, wherein said fixed core is provided at a portion of the circumference of said coil.

3. A solenoid valve as set forth in claim 1, wherein said fixed core is provided along the outer periphery of a housing that accommodates said movable core.

4. A solenoid valve according to claim 1, wherein the coil is provided in two stages in the axial direction.

5. A solenoid valve according to claim 1, wherein the coil is provided in two stages in the axial direction, and the fixed core is provided at positions of different phases in the circumferential direction of the coil.

6. A solenoid valve as claimed in any one of claims 1 to 5, wherein said fixed core is arc-shaped.

7. The solenoid valve according to claim 6, wherein said movable core is arcuate along said fixed core.

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