JP2011233790A - Solenoid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solenoid which can optionally control the position of a movable magnetic pole and which has a structure that can obtain a control stroke region of relatively bigger thrust than previous structures.SOLUTION: A salient 22 is provided in a movable magnetic pole 20 of a solenoid 10, and a concavity part 23 is provided in a fixed magnetic pole 40, trying to restrain the thrust which rapidly increases as the movable magnetic pole 20 approaches the fixed magnetic pole 40 because of the current of magnetic flux operated in the direction in which a shaft 83 progresses, namely the direction which is orthogonal to the operation direction of the thrust or the direction approximate to the orthogonal direction, namely because of the current of magnetic flux generating force which hardly or never contributes to the thrust. Therefore, the solenoid 10, which is made by the form of each implementation, can make a region of bigger thrust than the solenoids of the previous technology a control stroke region.

Description

  The present invention relates to a solenoid, and more particularly to a solenoid having a structure capable of arbitrarily controlling the position of a movable magnetic pole within a predetermined range.

  The so-called proportional solenoid, which has a structure that can arbitrarily control the position of the movable magnetic pole within a predetermined range, has a control stroke area in which the position of the movable magnetic pole can be arbitrarily controlled by the magnitude of the coil current and an approach stroke area in which the position cannot be controlled. And have. In this control stroke region, the thrust (attraction force) is almost constant regardless of the stroke (distance from the attracting point of the movable magnetic pole), but in the approach stroke region, the thrust varies greatly. In general proportional solenoids, only the control stroke area is used. Therefore, if the stroke in which the thrust is substantially constant can be increased, or if the thrust in the control stroke region can be increased, the use range of the solenoid is expanded, and various improvements have been made regarding these improvements.

  For example, in the solenoid described in Japanese Patent Application Laid-Open No. 2008-196642, a portion where the movable magnetic pole and the fixed magnetic pole are opposed to each other has a protruding portion that protrudes facing the other, and the other is opposed to the protruding portion. It has a concave portion to make. The thrust between the fixed magnetic pole and the movable magnetic pole gradually increases as the distance d between the base end of the convex portion and the distal end portion of the peripheral portion of the concave portion decreases, and thereafter, the distance d decreases within a predetermined distance range. It is set so as to decrease as the distance d further decreases and further increases as the distance d decreases. In this solenoid, the above configuration is used as a linear solenoid valve capable of changing the generated differential pressure in accordance with the current value of the coil.

  By the way, in the approach stroke region, in the region where the stroke is larger than the control stroke region, that is, the region where the convex portion and the concave portion are far from each other, the thrust decreases rapidly as the stroke increases. On the contrary, in the approach stroke region, in the region where the stroke is smaller than the control stroke region, that is, in the region where the convex portion and the concave portion are close, the thrust increases rapidly as the stroke becomes smaller. Therefore, if an attempt is made to obtain a larger thrust in the structure in which the opposing portion of the movable magnetic pole and the fixed magnetic pole is formed as a convex portion and a concave portion as described above, the thrust is increased in the approach stroke region where the stroke is larger than the control stroke region. A structure that is constant is much more advantageous than the opposite structure.

  As a means for making the thrust constant, it is known to process the outer peripheral portion of the recess into a tapered shape. However, such processing may adversely affect the reliability of the product, for example, the tapered portion may be deformed or dents may remain. Further, when the outer peripheral portion of the recess is thinned in a tapered shape, there is a problem that the thrust is reduced over the entire control stroke region.

JP 2008-196642 A

  In order to solve the above-described problems, an object of the present invention is to provide a solenoid having a structure in which a control stroke region having a relatively larger thrust than that of a conventional structure can be obtained in a solenoid capable of arbitrarily controlling the position of a movable magnetic pole. And

  According to the first aspect of the present invention, a coil, a fixed magnetic pole provided in the vicinity of the coil, and a movable provided so as to be slidable and attracted to the fixed magnetic pole when the coil is energized. In the solenoid having a magnetic pole, the fixed magnetic pole has a flat surface formed annularly or substantially annularly on the side facing the movable magnetic pole, and a recessed portion and a convex formed in a region surrounded by the flat surface. The movable magnetic pole is formed in an annular shape or a substantially annular shape on the side facing the fixed magnetic pole, and either the concave portion or the convex portion includes the other. And a concave portion and a convex portion formed in a region surrounded by the flat surface, and either one of the concave portion and the convex portion includes the other, And the recessed portion of the fixed magnetic pole and The convex part is designed to have an inverse relationship between the encapsulated part and the encapsulated part. When the coil is energized, the convex part of the movable magnetic pole is inserted into the concave part of the fixed magnetic pole. The concave portion of the movable magnetic pole is a solenoid in which the convex portion of the fixed magnetic pole is inserted.

  According to a second aspect of the present invention, in the first aspect of the present invention, the fixed magnetic pole has a through hole formed along a central axis, and the convex portion is formed at and near the center of the concave portion. One end of the through hole is opened at and near the center of the convex portion, and the movable magnetic pole has a through hole formed along a central axis, and the concave portion at the center of the convex portion and in the vicinity thereof. One end of the through hole is opened at the center of the recessed portion and in the vicinity thereof, and further, the bearing is fitted into the through hole of the fixed magnetic pole, and is fitted into the through hole of the movable magnetic pole. A solenoid having a shaft slidably supported by the bearing.

  According to a third aspect of the present invention, in the second aspect of the present invention, in the central axis direction, the fixed magnetic pole has a distance from the bottom surface of the recessed portion to the flat surface and the bottom surface of the recessed portion. The solenoid is characterized in that the distance to the tip of the convex portion is equal.

  According to a fourth aspect of the present invention, in the invention of the second or third aspect, the movable magnetic pole has a distance from a tip portion of the convex portion to the flat surface in the central axis direction, and the convex shape. The solenoid is characterized in that the distance from the tip of the part to the bottom surface of the recessed part is equal.

  The invention according to claim 5 is the invention according to any one of claims 2 to 4, wherein the fixed magnetic pole is further formed with another concave portion at the center of the convex portion and in the vicinity thereof. The movable magnetic pole has another convex part formed so as to be opposed to the other concave part of the fixed magnetic pole at the center of the concave part and in the vicinity thereof and to be inserted into the other concave part of the fixed magnetic pole. Further, the solenoid is characterized by being formed.

  According to a sixth aspect of the invention, in the fifth aspect of the invention, the movable magnetic pole is formed with a step so that one or both of the convex portion and the other convex portion has a narrow width on the tip side. It is the solenoid characterized by having.

  The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein the movable magnetic pole or the fixed magnetic pole includes the concave portion among the convex portions. The solenoid is characterized in that a cut is formed from the outer peripheral surface to the recessed portion.

  The invention according to claim 8 is the invention according to any one of claims 1 to 7, wherein a flat surface that is fixed to the movable magnetic pole and orthogonal to the operating direction of the movable magnetic pole is formed. The auxiliary magnetic pole is partly or entirely formed into a cylindrical shape, and the fixed magnetic pole is fitted therein, and a flat surface opposite to the flat surface of the auxiliary magnetic pole is formed in the vicinity of the flat surface of the auxiliary magnetic pole. The solenoid further includes a magnetic case.

  According to the first aspect of the present invention, the movable magnetic pole is operated by energizing the coil, and the convex portion of the movable magnetic pole is inserted into the concave portion of the fixed magnetic pole, or the convex portion of the fixed magnetic pole is the concave portion of the movable magnetic pole. When the two magnetic poles approach each other until they are inserted into the magnetic pole, a magnetic flux flows from the outer surface and the inner surface of the convex portion of the movable magnetic pole toward the inner surface of the concave portion of the fixed magnetic pole and the peripheral side surface of the convex portion. This flow of magnetic flux is a flow in a direction perpendicular to or close to the operation direction of the movable magnetic pole. As the convex portions of the two magnetic poles are inserted deeply into the recesses on the other side, these flows Will grow. Accordingly, in the process from when the convex portions of the two magnetic poles start to be inserted into the recesses on the other side until the flat surface of the movable magnetic pole is attracted to the flat surface of the fixed magnetic pole, the flow of the two magnetic fluxes is The thrust that increases rapidly as it approaches is reduced and made almost constant. On the other hand, in the solenoid according to the prior art, since both the convex portion and the concave portion are not formed on the two magnetic poles, the flow of magnetic flux is one. Therefore, the thrust can be made almost constant in a region where the solenoid according to the prior art cannot be realized, and the region where the thrust is larger than the conventional one can be set as the control stroke region.

  According to the second aspect of the present invention, since the fixed magnetic pole is formed so that the convex portion is included in the concave portion, the opening of the through hole is higher than the bottom surface of the concave portion, that is, the concave portion. It is located on the movable magnetic pole side from the bottom surface. Therefore, the distance from this end to the periphery of the opening of the through hole can be made longer than the distance from the end of the fixed magnetic pole opposite to the movable magnetic pole to the bottom surface of the recess, and it fits into the through hole. Longer bearings can be employed. As a result, since the shakiness of the shaft is reduced by adopting the long bearing, the sliding of the shaft becomes more stable.

  According to the third aspect of the present invention, the substantially entire process until the movable magnetic pole is attracted to the fixed magnetic pole, the outer surface and the inner surface of the convex portion of the movable magnetic pole, The flow of magnetic flux toward the peripheral side of the convex part continues to reduce the thrust. Therefore, the thrust can be made more constant.

  According to the fourth aspect of the present invention, from the outer surface and the inner surface of the convex portion of the movable magnetic pole to the inner surface of the concave portion of the fixed magnetic pole, over almost the entire process until the movable magnetic pole is attracted to the fixed magnetic pole. The flow of magnetic flux toward the peripheral side of the convex part continues to reduce the thrust. Therefore, the thrust can be made more constant.

  According to the fifth aspect of the present invention, since another concave portion is formed on the fixed magnetic pole and at the same time, another convex portion is formed on the movable magnetic pole, the direction perpendicular to the operation direction of the movable magnetic pole or this direction It is possible to generate two new magnetic flux flows in a direction close to, thereby further reducing the thrust and making the thrust more constant.

  According to the invention described in claim 6, by providing a step that narrows the width on the tip side of the convex portion, the outer surface or the inner surface of the portion above the step and the concave portion into which the convex portion is inserted. Since the distance to the outer side surface or the inner side surface is increased, the flow in the direction perpendicular to the operation direction of the movable magnetic pole or in the direction close to this direction can be slightly weakened. Therefore, it is possible to adjust the stroke that becomes the control stroke region and the thrust in the specific stroke.

  According to the seventh aspect of the present invention, the area of the outer side surface and the inner side surface of the convex portion can be reduced by the cut extending from the outer peripheral surface to the concave portion, so that the direction perpendicular to the operating direction of the movable magnetic pole or in this direction The flow in the near direction can be slightly weakened. Therefore, it is possible to adjust the stroke that becomes the control stroke region and the thrust in the specific stroke.

  According to the eighth aspect of the present invention, since the attracting force acts between the auxiliary magnetic pole and the case to increase the thrust, the thrust can be increased in a situation where the initial thrust of the movable magnetic pole is weak. Further, the size of the opposed surfaces of the movable magnetic pole and the fixed magnetic pole can be reduced by an amount corresponding to the thrust assisted by the auxiliary magnetic pole.

It is sectional drawing of the solenoid which concerns on the 1st Embodiment of this invention, (A) shows the state from which the movable magnetic pole was separated from the fixed magnetic pole, (B) shows the state by which the movable magnetic pole was adsorbed by the fixed magnetic pole. It is explanatory drawing of the solenoid which concerns on the 1st Embodiment of this invention, (A) is a front view, (B) is a right view. It is a cross-sectional perspective view of the movable magnetic pole of the solenoid which concerns on the 1st Embodiment of this invention. It is a section perspective view of the fixed magnetic pole of the solenoid concerning a 1st embodiment of the present invention. It is sectional drawing which shows the flow of magnetic flux, (A) shows the state in which the movable magnetic pole is the furthest from the fixed magnetic pole, (B) shows the state in which the movable magnetic pole approaches the fixed magnetic pole, and (C) shows the state in which energization is stopped. It is explanatory drawing of a comparative example, (A) is sectional drawing, (B) is sectional drawing which shows the flow of the magnetic flux in the state in which the movable magnetic pole approached the fixed magnetic pole. It is explanatory drawing of a comparative example, (A) is sectional drawing of a movable magnetic pole, (B) is sectional drawing of a fixed magnetic pole. It is a graph which shows the result of the comparison experiment of thrust. It is explanatory drawing of the solenoid which concerns on the 2nd Embodiment of this invention, (A) is a cross-sectional perspective view of a movable magnetic pole, (B) is a cross-sectional perspective view of a fixed magnetic pole. It is a cross-sectional perspective view of the movable magnetic pole of the solenoid which concerns on the 3rd Embodiment of this invention. It is a cross-sectional perspective view of the fixed magnetic pole of the solenoid which concerns on the 3rd Embodiment of this invention. It is a cross-sectional perspective view of the movable magnetic pole of the solenoid which concerns on the 4th Embodiment of this invention. It is sectional drawing of the solenoid which concerns on the 5th Embodiment of this invention, (A) shows the state in which the movable magnetic pole was separated from the fixed magnetic pole, (B) shows the state in which the movable magnetic pole was adsorbed by the fixed magnetic pole. It is a cross-sectional perspective view of the movable magnetic pole of the solenoid which concerns on the 5th Embodiment of this invention. It is a cross-sectional perspective view of the fixed magnetic pole of the solenoid which concerns on the 5th Embodiment of this invention. It is a cross-sectional perspective view of the movable magnetic pole of the solenoid which concerns on the 6th Embodiment of this invention. It is a cross-sectional perspective view of the fixed magnetic pole of the solenoid which concerns on the 6th Embodiment of this invention. It is a cross-sectional perspective view of the movable magnetic pole of the solenoid which concerns on the 7th Embodiment of this invention. It is a cross-sectional perspective view of the fixed magnetic pole of the solenoid which concerns on the 7th Embodiment of this invention. It is explanatory drawing of the solenoid which concerns on the 8th Embodiment of this invention, (A) is a cross-sectional perspective view of a movable magnetic pole, (B) is a cross-sectional perspective view of a fixed magnetic pole, (C) is a modification of a convex part. It is a perspective view shown. It is explanatory drawing of the solenoid which concerns on the 9th Embodiment of this invention, (A) is a cross-sectional perspective view of a movable magnetic pole, (B) is a cross-sectional perspective view of a fixed magnetic pole.

  Below, the solenoid concerning each embodiment of the present invention is explained based on a drawing. Each embodiment will be described based on a structure in which the solenoid is independent. However, each embodiment of the present invention can be preferably applied to a solenoid valve. For example, a coil, a fixed magnetic pole provided in the vicinity of the coil, a movable magnetic pole provided to be attracted to the fixed magnetic pole when the coil is energized, and a valve body connected to the movable magnetic pole, In the solenoid valve having a valve seat provided so as to be able to contact with and separate from the valve body, the fixed magnetic pole includes a flat surface formed in an annular shape, a recessed portion formed in a region surrounded by the flat surface, The movable magnetic pole is surrounded by an annular flat surface formed so as to face the flat surface of the fixed magnetic pole and the flat surface. A convex portion formed in the region so as to face the concave portion of the fixed magnetic pole, and a concave portion formed so as to face the convex portion of the fixed magnetic pole at and near the center of the convex portion. When the coil is energized, the movable magnetic pole The convex portion is inserted into the concave portion of the fixed magnetic pole, the convex portion of the fixed magnetic pole is inserted into the concave portion of the movable magnetic pole, and the valve body is attached when the movable magnetic pole is attracted to the fixed magnetic pole. It is possible to provide a solenoid valve characterized by being in contact with the valve seat.

  1A and 1B are sectional views of a solenoid according to a first embodiment of the present invention, in which FIG. 1A shows a state in which the movable magnetic pole is separated from the fixed magnetic pole, and FIG. 1B shows a state in which the movable magnetic pole is attracted to the fixed magnetic pole. 1, 10 is a solenoid, 20 is a movable magnetic pole, 22 is a convex part, 40 is a fixed magnetic pole, 48 is a lid part, 51a and 51b are screw holes, 80 is an auxiliary magnetic pole, 81 is a case, and 82 is a counter part. , 83 is a shaft, 84 is a screw hole, 85 is a coil bobbin, 86 is a coil, 87a and 87b are lead wires, 88 is an insulation coating, and 89 is a sleeve. Moreover, FIG. 2 is explanatory drawing of the solenoid which concerns on the 1st Embodiment of this invention, (A) is a front view, (B) is a right view. The reference numerals used in FIG. 2 are the same as those in FIG. 1 and other drawings describing the solenoid or each component, the right side of these drawings will be referred to as the front end side of the solenoid or each component, and the left side will be referred to as the base end side of the solenoid or each component. .

  First, an outline of the overall structure of the solenoid according to this embodiment will be described. As shown in FIGS. 1 and 2, the solenoid 10 houses the movable magnetic pole 20, the fixed magnetic pole 40, the shaft 83, the coil bobbin 85, the coil 86, and the sleeve 89 inside a short substantially cylindrical case 81, and an auxiliary magnetic pole 80 is provided outside the case 81. Furthermore, the movable magnetic pole 20 and a part of the shaft 83 are exposed outside the case 81. The case 81 is made of a magnetic material, and has a facing portion 82 on the base end side. The facing portion 82 is formed in a circular plate shape having an opening at the center. Further, in order to generate a magnetic flux flow between the coil 86 and the auxiliary magnetic pole 80 when energized, the coil 86 is provided so as to face the auxiliary magnetic pole 80, that is, in a direction orthogonal to the central axis of the shaft 83. Note that the central axis of the movable magnetic pole 20 and the central axis of the shaft 83 coincide with each other. Therefore, in the following description, for example, the surface defined as the surface orthogonal to the central axis direction of the shaft 83 is also the central axis of the movable magnetic pole 20. Orthogonal. Further, the movable magnetic pole 20 is inserted into the opening at the center of the facing portion 82, and the end of the facing portion 82 is in a state of being very close to the movable magnetic pole 20. Further, a lid 48 of the fixed magnetic pole 40 is fitted to the end of the case 81 on the front end side. Note that the outer shape of the case 81 may be formed in an elliptical cylindrical shape, a rectangular cylindrical shape, a hexagonal cylindrical shape, or the like. The case 81 may omit the facing portion 82 when the auxiliary magnetic pole 80 is not provided. Furthermore, when it is desired to form the lid 48 on the fixed magnetic pole 40, a lid may be provided separately.

  FIG. 3 is a cross-sectional perspective view of the movable magnetic pole of the solenoid according to the first embodiment of the present invention. In FIG. 3, 21 is a flat surface, 23 is a recessed portion, 24 is a bottom surface, 25 is a top surface, 26 is an outer surface, 27 is an inner surface, 28 is a large diameter portion, 29 is a small diameter portion, and 30 is a through hole. Other reference numerals are the same as those in FIG. FIG. 4 is a cross-sectional perspective view of the fixed magnetic pole of the solenoid according to the first embodiment of the present invention. In FIG. 4, 41 is a flat surface, 42 is a recessed portion, 43 is a bottom surface, 44 is an outer surface, 45 is an inner surface, 46 is a convex portion, 47 is a trunk portion, 49 is a top surface, 50 is a through hole, 51a and 51b. Is a screw hole, 52 is an edge, and the other symbols are the same as in FIG.

  As shown in FIG. 3, the movable magnetic pole 20 is a magnetic component formed in a short cylindrical shape as a whole. Further, a part on the base end side is a small diameter part 29 having a smaller diameter than the other part, and the other part is a large diameter part 28. The large diameter portion 28 has a diameter slightly smaller than the diameter of the opening formed at the center of the facing portion 82 of the case 81, and is set so that the movement of the movable magnetic pole 20 is not hindered by the opening. The small diameter portion 29 is a portion into which the auxiliary magnetic pole 80 is fitted, and is set to have a diameter suitable for fitting an opening formed at the center of the auxiliary magnetic pole 80. In addition, you may form the whole shape of the movable magnetic pole 20 in other shapes, such as a short elliptic cylinder shape, a hexagonal cylinder shape, and an octagonal cylinder shape. Furthermore, when applied to a solenoid valve, for example, a part of the movable magnetic pole 20 can be formed as a valve body, or a valve body made of a nonmagnetic material can be fixed to the distal end side of the movable magnetic pole 20. . The method for controlling the position of the movable magnetic pole 20 according to the magnitude of the current of the coil is not described because a conventional technique can be applied.

  The movable magnetic pole 20 has a through hole 30 at the center and the vicinity thereof along the central axis. The through hole 30 is a hole into which the shaft 83 is fitted, and is formed in a size in consideration of the diameter of the shaft 83. Since the shaft 83 is supported by the sleeve 89 which is a bearing, the movable magnetic pole 20 is indirectly supported by the sleeve 89. Further, the flat surface 21 of the movable magnetic pole 20 is formed in an annular shape along the edge of the side surface of the distal end of the movable magnetic pole 20, and is formed so as to be orthogonal to the central axis of the shaft 83. In the region surrounded by the flat surface 21, the convex portion 22 is formed in an annular shape. Furthermore, a concave portion 23 is formed at the center of the convex portion 22 and in the vicinity thereof. In the recessed portion 23, the opening of the through hole 30 is exposed at the center of the bottom surface 24 and in the vicinity thereof. Further, the flat surface 21 and the recessed portion 23 are disposed on the same virtual plane orthogonal to the central axis of the shaft 83, and face the flat surface 41 and the upper surface 49 of the fixed magnetic pole 40 described later. Yes.

  The convex portion 22 is formed to obtain a control stroke region having a relatively larger thrust than the conventional structure, and is a core portion of the present invention. Further, it is formed so as to face a recessed portion 42 of the fixed magnetic pole 40 described later, and the thrust in the control stroke region is adjusted by the magnetic flux flowing between the recessed portion 42 of the fixed magnetic pole 40. Further, the upper surface 25 of the convex portion 22 is formed as an annular flat surface, and is formed so as to be orthogonal to the central axis of the shaft 83. The top surface 25 faces the bottom surface 43 of the recessed portion 42 of the fixed magnetic pole 40, and acts to attract the magnetic pole 20 to the fixed magnetic pole 40, that is, the magnetic flux that attracts the top surface 25 to the bottom surface 43 when the coil 86 is energized. It becomes a path of magnetic flux to be generated. The upper surface 25 of the convex portion 22 and its vicinity can be formed as, for example, a convex curved surface or an inverted V-shaped curved surface. In this case, the upper surface 25 is parallel to the central axis of the shaft 83. Since a magnetic flux that does not flow in the flow path is generated, which causes a reduction in thrust, a flat surface is desirable.

  Further, the outer surface 26 and the inner surface 27 of the convex portion 22 are formed as surfaces parallel to the central axis of the shaft 83, respectively. Further, the outer surface 26 and the inner surface 27 face each other with respect to the outer surface 44 and the inner surface 45 of the recessed portion 42 of the fixed magnetic pole 40 when the convex portion 22 enters the recessed portion 42 of the fixed magnetic pole 40. When the coil 86 is energized, a magnetic flux also flows between them. The magnetic flux flowing between them generates a force that attracts these facing surfaces to each other, and therefore does not contribute to the thrust of the solenoid 10 or contributes little. The outer side surface 26 and the inner side surface 27 can be formed, for example, as a tapered surface or a gently curved surface, but when the convex portion 22 enters the concave portion 42 of the fixed magnetic pole 40, the solenoid 10. Since the ratio that contributes to the thrust becomes higher, it is desirable to use a vertical plane. The outer side surface 26 and the inner side surface 27 have the same length from the flat surface 21 to the upper surface 25 and the length from the bottom surface 24 to the upper surface 25. That is, although the length with respect to the central-axis direction of the movable magnetic pole 20 and the shaft 83 is made the same, these lengths may differ. However, if there is a large difference between these lengths, the magnetic fluxes flowing from the outer side surface 26 and the inner side surface 27 to the outer side surface 44 and the inner side surface 45 of the fixed magnetic pole 40 will be biased. Since the change in thrust in the process of being attracted to the fixed magnetic pole 40 becomes large, it is desirable that these lengths are the same.

  The fixed magnetic pole 40 is a magnetic component, and as shown in FIG. 4, the entire structure is provided with a substantially circular plate-like lid portion 48 on the front end side of a thick substantially cylindrical body portion 47. . The fixed magnetic pole 40 has a through hole 50 at the center and its vicinity along the central axis. The through hole 50 is a hole for fitting the sleeve 89, and is formed in a size considering the outer diameter of the sleeve 89. Note that the entire shape of the fixed magnetic pole 40 may be formed in other shapes such as a short elliptical cylinder, a hexagonal cylinder, and an octagonal cylinder, like the movable magnetic pole 20. Further, when applied to a solenoid valve, for example, a part of the fixed magnetic pole 40 can be formed as a valve seat, or a valve seat made of a nonmagnetic material can be fixed to the tip side of the fixed magnetic pole 40. . The lid 48 may be a separate body.

  The body portion 47 is a main portion constituting the magnetic circuit, and forms an annular flat surface 41 along the edge of the base end face. The flat surface 41 of the fixed magnetic pole 40 is formed so as to be orthogonal to the central axis of the shaft 83 and faces the flat surface 21 of the movable magnetic pole 20. In the region surrounded by the flat surface 41, a recessed portion 42 is formed in an annular shape. Further, a convex portion 46 is formed at the center of the concave portion 42 and in the vicinity thereof. The entire protrusion 46 is flat, and the opening of the through hole 50 is exposed at the center and the vicinity thereof. Further, the flat surface 41 and the upper surface 49 are disposed on the same virtual plane orthogonal to the central axis of the shaft 83, and face the flat surface 21 and the bottom surface 24 of the movable magnetic pole 40.

  The recessed portion 42 is formed to obtain a control stroke region having a relatively larger thrust than the conventional structure, and is a core portion of the present invention together with the convex portion 22 of the movable magnetic pole 20. In addition, the bottom surface 43 of the recessed portion 42 is formed as an annular flat surface, and is formed so as to be orthogonal to the central axis of the shaft 83. The bottom surface 43 faces the bottom surface 43 of the convex portion 22 of the movable magnetic pole 20 and acts to attract the magnetic pole 20 to the fixed magnetic pole 40, that is, the magnetic flux that attracts the top surface 25 to the bottom surface 43 when the coil 86 is energized. It becomes a path of magnetic flux to be generated. The bottom surface 43 of the recessed portion 42 can be formed as a concave curved surface or a V-shaped bent surface, for example, depending on the shape of the upper surface 25 of the convex portion 22 of the movable magnetic pole 20 and the vicinity thereof. When formed in this way, a magnetic flux that flows parallel to the central axis of the shaft 83 is generated, which causes a sudden increase in thrust.

  Further, the outer surface 44 and the inner surface 45 of the recessed portion 42 are each formed as a vertical surface parallel to the central axis of the shaft 83. The outer surface 44 and the inner surface 45 are very different from the outer surface 44 and the inner surface 45 of the recessed portion 42 of the fixed magnetic pole 40 when the convex portion 22 of the movable magnetic pole 20 enters the recessed portion 42. Face up in close proximity. In particular, when the distance between these side surfaces is closer than the distance between the bottom surface 43 of the recessed portion 42 and the upper surface 25 of the convex portion 22, the amount of magnetic flux flowing between these side surfaces is greater. The magnetic flux flowing between these side surfaces generates a force that attracts these facing surfaces to each other, and therefore does not contribute to the thrust of the solenoid 10 or contributes little, so the thrust is kept constant. It can be said that the effect is great.

  The outer surface 44 and the inner surface 45 can be formed, for example, in a tapered surface or a gently curved surface, but when the convex portion 22 of the movable magnetic pole 20 enters the concave portion 42, the solenoid 10. Since the ratio that contributes to the thrust becomes higher, it is desirable to use a vertical plane. Further, the outer surface 44 and the inner surface 45 have the same length from the bottom surface 43 to the flat surface 41 and the length from the bottom surface 43 to the upper surface 49. That is, although the length with respect to the central-axis direction of the movable magnetic pole 20 and the shaft 83 is made the same, these lengths may differ. However, if there is a large difference between these lengths, the thrust in the control stroke region is weakened, as will be described later, and it is desirable that these lengths be the same.

  Further, a convex portion 46 is formed in a region surrounded by the concave portion 42 on the base end face of the body portion 47. The convex portion 46 has an action according to the convex portion 22 of the movable magnetic pole 20. That is, the inner side surface 45 of the concave portion 42 has the same positional relationship as the outer side surface 26 of the convex portion 22 when viewed from the convex portion 46, and between the inner side surface 27 of the convex portion 22 when the coil 86 is energized. Magnetic flux flows through The magnetic flux flowing between them generates a force that tries to attract these surfaces, and therefore does not contribute to the thrust of the solenoid 10 or contributes little. Note that the inner surface of the through hole 50 does not act like the inner surface 45 because the shaft 83 is fitted therein. Further, the upper surface 49 of the convex portion 46 faces the bottom surface 24 of the concave portion 23 so that the magnetic flux that attracts the bottom surface 24 to the upper surface 49 when the coil 86 is energized, that is, the movable magnetic pole 20 is attracted to the fixed magnetic pole 40. It becomes the path of the magnetic flux acting on. Lid 48 literally serves as an end cap for case 81, but also serves as part of the magnetic circuit. The lid portion 48 is provided with screw holes 51a and 51b so that the solenoid 10 can be attached to a load device or the like.

  As shown in FIGS. 1 and 2, the auxiliary magnetic pole 80 is formed in a substantially circular plate shape, and has an opening for fitting the movable magnetic pole 20 at the center. Further, the surface on the tip side of the auxiliary magnetic pole 80 faces the facing portion 82 of the case 81, and when the coil 86 is energized, a magnetic flux flows from the facing portion 82 to the movable magnetic pole 20 via the auxiliary magnetic pole 80. A force for attracting the auxiliary magnetic pole 80 to the facing portion 82 is generated. In this embodiment, the auxiliary magnetic pole 80 is provided outside the case 81, thereby reducing restrictions on the size of the auxiliary magnetic pole 80. That is, the area of the auxiliary magnetic pole 80 is increased to increase the flow of magnetic flux so that the largest possible thrust can be obtained. In particular, since the thrust is small when the stroke is large, assisting the thrust by the auxiliary magnetic pole 80 is effective. Further, the size of the surface on the distal end side of the movable magnetic pole 20 and the base end side of the fixed magnetic pole can be reduced by an amount corresponding to the thrust assisted by the auxiliary magnetic pole 80, which contributes to miniaturization of these magnetic poles.

  The coil bobbin 85 is housed inside the case 81 and is in contact with the fixed magnetic pole 40. The coil 86 is wound around the coil bobbin 85. Note that the coil bobbin 85 and the coil 86 may have any size and shape as long as they generate a magnetic circuit to be described later. The sleeve 89 is fitted in the through hole 50 of the fixed magnetic pole 40. Instead of the sleeve 89, another type of bearing such as a linear bush may be provided. The shaft 83 is supported by the sleeve 89 on the distal end side, and supports the movable magnetic pole 20 fitted on the proximal end side. Further, a screw hole 84 is formed from the distal end of the shaft 83 toward the proximal end side to facilitate connection to the load device. Therefore, as shown in FIG. 1B, when the movable magnetic pole 20 moves away from the fixed magnetic pole 40, the auxiliary magnetic pole 80 and the shaft 89 also move together. In this embodiment, as shown in FIG. 1A, when the movable magnetic pole 20 is attracted to the fixed magnetic pole 40, the upper surface 25 of the convex portion 22 and the bottom surface 43 of the concave portion 42 come into contact with each other. Any one or both of the flat surface 21 and the flat surface 41 and the bottom surface 24 and the top surface 49 may be in contact with each other. The lead wires 87a and 87b are connected to the coil 86, and some of them are not shown, but most of them are covered with an insulating coating 88.

  Next, a comparative experiment between the solenoid to which the first embodiment of the present invention is applied and the solenoid to which the conventional structure is applied will be described. 5A and 5B are cross-sectional views showing the flow of magnetic flux. FIG. 5A is a state in which the movable magnetic pole is farthest from the fixed magnetic pole, FIG. 5B is a state in which the movable magnetic pole is close to the fixed magnetic pole, and FIG. Indicates the state. Reference numerals used in FIGS. 5 and 6 are the same as those in FIG. 6A and 6B are explanatory diagrams of a comparative example, in which FIG. 6A is a cross-sectional view and FIG. 6B is a cross-sectional view showing the flow of magnetic flux when the movable magnetic pole approaches the fixed magnetic pole. In FIG. 6, 11 is a solenoid, 37 is a convex part, 52 is an edge part, and other symbols used are the same as those in FIG. In addition, FIG. 7 is an explanatory view of a comparative example, (A) is a sectional view of the movable magnetic pole, and (B) is a sectional view of the fixed magnetic pole. In FIG. 7, 38 is an upper surface, 39 is an outer surface, 53 is a recessed portion, 54 is a flat surface, 55 is a bottom surface, 56 is an outer surface, and the other symbols used are the same as those in FIG. FIG. 8 is a graph showing the results of a thrust comparison experiment.

  In this experiment, the structure shown in FIG. 1 was used as the structure of the present invention, and the structure shown in FIGS. 6 and 7 was used as a comparative example of the conventional structure. That is, as shown in FIG. 7A, the solenoid 11 has a convex portion 37 formed on the tip side of the movable magnetic pole 20, and the only surface that is parallel to the central axis of the shaft 83 is the outer surface 39. As shown in FIG. 7B, the fixed magnetic pole 40 of the solenoid 11 has a recessed portion 53 formed in a region surrounded by the upper surface 54 of the edge portion 52, but is parallel to the central axis of the shaft 83. The only surface is the outer surface 56. In other words, the solenoid 11 has a simple uneven combination on the opposed surfaces of the movable magnetic pole 20 and the fixed magnetic pole 40. The other structures and shapes of the solenoid 11 are the same as those of the solenoid 10 of the first embodiment. The maximum stroke was set to 3.5 mm for both the present invention and the comparative example.

  The graph of FIG. 8 shows the result of measuring the thrust (attraction force) by passing a current of 0.9 A through the above two solenoids. As shown in FIG. 8, in the solenoid 10 having the structure of the present invention, the stroke is in a range slightly less than 1 mm to slightly more than 2 mm, and in the solenoid 11 having the conventional structure, the stroke is in a range slightly less than 1.5 mm to slightly more than 2.5 mm. The change in thrust is small and the curve is almost flat. That is, both have a control stroke area of slightly over 1 mm. Focusing on the magnitude of the thrust in these control stroke regions, the solenoid 10 having the structure of the present invention has a value of approximately 50 to 55 N, whereas the solenoid 11 having the conventional structure has a value of approximately 30 to 35 N. Therefore, it was found that the solenoid 10 having the structure of the present invention can obtain a control stroke region having a larger thrust than the solenoid 11 having the conventional structure.

  In addition to the above experiments, magnetic field analysis was performed on the structure of the present invention and the conventional structure, and the operation and effect of the structure of the present invention were comprehensively considered. As a result, in the solenoid 10, the concave and convex shapes on the opposite sides of the movable magnetic pole 20 and the fixed magnetic pole 40 are more complicated and have a larger surface area than the solenoid 11. Further, as shown in FIG. 5A, when the movable magnetic pole 20 and the fixed magnetic pole 40 begin to approach each other from the farthest position, the outer surface 26 of the movable magnetic pole 20 and the outer surface 44 of the fixed magnetic pole 40 and the vicinity thereof. And the magnetic flux flowing from the inner surface 27 of the movable magnetic pole 20 to the inner surface 45 of the fixed magnetic pole 40 and the vicinity thereof are larger than in the conventional structure, and the thrust is larger than that in the conventional structure.

  Then, as shown in FIG. 5B, when the movable magnetic pole 20 and the fixed magnetic pole 40 approach each other to some extent, the outer surface 26 and the outer surface 44 and the inner surface 27 and the inner surface 45 face each other while approaching each other. Therefore, the amount of magnetic flux flowing between these surfaces is relatively larger than the amount of magnetic flux flowing between the bottom surface 24 and the top surface 49, between the flat surface 21 and the flat surface 41, and the like. Therefore, the force for adsorbing the outer surface 26 and the outer surface 44 and the inner surface 27 and the inner surface 45 is relatively larger than the force adsorbing the bottom surface 24 and the upper surface 49 and the flat surface 21 and the flat surface 41. go. The force for attracting these side surfaces acts in the direction in which the shaft 83 advances, that is, in the direction orthogonal to the direction in which the thrust is applied, or in the direction close to the direction orthogonal, and therefore does not contribute or hardly contribute to the thrust. Therefore, when the force for adsorbing these side surfaces becomes relatively larger than the force for adsorbing the bottom surface 24 and the upper surface 49 and the flat surface 21 and the flat surface 41, an increase in thrust is suppressed. . When the movable magnetic pole 20 and the fixed magnetic pole 40 are very close to each other, for example, at a stroke of 1 mm or less, the bottom face 24 and the top face 49 and the flat face 21 and the flat face 41 are also very close to each other. The amount of magnetic flux is overwhelmingly larger than the amount of magnetic flux flowing between the outer surface 26 and the outer surface 44 and between the inner surface 27 and the inner surface 45. Then, as can be seen from FIG. 6, the thrust increases rapidly, so that the movable magnetic pole 20 is attracted to the fixed magnetic pole 40 as shown in FIG.

  In contrast, in the solenoid 11, the amount of magnetic flux flowing between the top surface 38 of the movable magnetic pole 20 shown in FIG. 7A and the bottom surface 55 of the fixed magnetic pole 40 shown in FIG. The amount of magnetic flux flowing between the outer surface 39 of the movable magnetic pole 20 shown in FIG. 6 and the outer surface 56 of the fixed magnetic pole 40 shown in FIG. Therefore, when the movable magnetic pole 20 and the fixed magnetic pole 40 begin to approach from the position where they are farthest, the thrust becomes relatively weak. Further, when the movable magnetic pole 20 and the fixed magnetic pole 40 are closer than the position shown in FIG. 6B, the top surface 38 and the bottom surface 55 are reduced to the extent that there is no effect of thrust suppression by the inner surface 27 and the inner surface 45 of the solenoid 10. Since the amount of magnetic flux flowing between them begins to increase rapidly, the thrust also increases at an accelerated rate. Therefore, what can be used as the control stroke area in the solenoid 11 is an area where the stroke is larger than that of the solenoid 10, that is, an area where the thrust is small. As described above, when the solenoid 10 to which the first embodiment of the present invention is applied and the solenoid 11 to which the conventional structure is applied are compared, it is found that the solenoid 10 has a larger thrust in the control stroke region.

  In the solenoid 10 used in the experiment, the outer surface 26, the outer surface 44, the inner surface 27, and the inner surface 45 have the same length in the central axis direction of the movable magnetic pole 20 and the shaft 83. When the length of the inner side surface 45 is half of the length of the outer side surface 26 and the outer side surface 44, the amount of magnetic flux flowing between the inner side surface 27 and the inner side surface 45 is reduced, and the inner side surface 27 and the inner side surface 45 are separated. The adsorbing power is also weakened. In other words, the inner side surface 27 and the inner side surface 45 and the structure of the portion closer to the shaft than these surfaces are closer to the conventional structure. Therefore, when the thrust of such a solenoid is measured, the thrust is intermediate between the structure of the present invention and the conventional structure. After all, even with such a structure, the thrust in the control stroke region can be increased to some extent, but the length of the movable magnetic pole 20 and the shaft 83 in the central axis direction on the outer surface 44, the inner surface 27 and the inner surface 45 are the same. It can be said that it is more desirable. Further, it is desirable that the distances between the outer surface 26 and the outer surface 44 and between the inner surface 27 and the inner surface 45 are as close as possible from the viewpoint of allowing more magnetic flux to flow.

  Furthermore, a solenoid according to a second embodiment of the present invention will be described. FIG. 9 is an explanatory view of a solenoid according to a second embodiment of the present invention, in which (A) is a cross-sectional perspective view of a movable magnetic pole, and (B) is a cross-sectional perspective view of a fixed magnetic pole. Reference numerals used in FIG. 9 are the same as those in FIG. In addition, the part which is not shown in figure is the same as the solenoid which concerns on 1st Embodiment except the part demonstrated below. In the solenoid according to this embodiment, the distance between the outer surface 26 and the inner surface 27 is increased by increasing the width of the convex portion 22 of the movable magnetic pole 20. Further, the distance between the outer surface 44 and the inner surface 45 of the recessed portion 42 of the fixed magnetic pole 40 also corresponds to the convex portion 22. Thus, the control stroke area is adjusted by appropriately adjusting the width of the convex portion 22, for example, the control stroke area of 1.2 mm to 2.5 mm is set to 1.0 mm to 2.3 mm, or vice versa. Can be adjusted.

  Next, a solenoid according to a third embodiment of the present invention will be described. FIG. 10 is a cross-sectional perspective view of the movable magnetic pole of the solenoid according to the third embodiment of the present invention. In FIG. 10, 31 is a convex part, 32 is a bottom face, 33 is a top face, 34 is an outer side face, 35 is an inner side face, and other symbols are the same as those in FIG. FIG. 11 is a cross-sectional perspective view of the fixed magnetic pole of the solenoid according to the third embodiment of the present invention. In FIG. 11, 57 is a recessed part, 58 is a bottom surface, 59 is an outer surface, 60 is an inner surface, 61 is an upper surface, and other symbols are the same as those in FIG. In addition, the part which is not shown in figure is the same as the solenoid which concerns on 1st Embodiment except the part demonstrated below. In the solenoid according to this embodiment, the convex portion 22 and the convex portion 31 are provided on the movable magnetic pole 20 so that the upper surface 25 and the upper surface 33 have the same width. The shape of the fixed magnetic pole 40 is also provided with a recessed portion 42 and a recessed portion 57 in accordance with the protruding portion 22 and the protruding portion 31. For example, when the diameter of the solenoid is large enough to secure the bottom surface 32 around the opening of the through-hole 30, by providing two convex portions on the movable magnetic pole 20, the outer surface 26, the inner surface 27, the outer surface Four side surfaces 34 and an inner side surface 35 are formed. Further, the fixed magnetic pole 40 also forms four side surfaces: an outer surface 44, an inner surface 45, an outer surface 59, and an inner surface 60. These four sets of opposing side faces further suppress an acceleration increase in thrust, and a control stroke region having a larger thrust can be obtained. In this embodiment, the lengths of the convex portion 22 and the convex portion 31 in the central axis direction of the movable magnetic pole 20 and the shaft 83 are the same, but they may be different. When different, the lengths of the movable magnetic pole 20 and the shaft 83 in the central axis direction of the concave portion 42 and the concave portion 57 of the fixed magnetic pole 40 need to be varied accordingly.

  Furthermore, a solenoid according to a fourth embodiment of the present invention will be described. FIG. 12 is a cross-sectional perspective view of the movable magnetic pole of the solenoid according to the fourth embodiment of the present invention. In FIG. 12, reference numeral 36 denotes a notch groove, and other reference numerals are the same as those in FIG. In addition, the part which is not shown in figure is the same as the solenoid which concerns on 1st Embodiment except the part demonstrated below. In the solenoid according to this embodiment, a notch groove 36 is formed along the central axis on the outer peripheral surface of the movable magnetic pole 20, and the notch groove 36 extends to a part of the convex portion 22. Thus, for structural reasons, the present invention can be preferably applied to a structure in which a part of the convex portion 22 is notched, such as when a groove is formed on the outer peripheral surface of the movable magnetic pole 20.

  In the above embodiment, in the fixed magnetic pole, the concave portion is included in the annular flat surface, that is, the periphery is surrounded, and the convex portion is included in the concave portion, and in the movable magnetic pole, the convex portion is included in the annular flat surface. It was included, and it was set as the structure by which the recessed part was included in the convex part. However, in the present invention, the concave and convex portions of the fixed magnetic pole and the movable magnetic pole can be arranged opposite to each other. Further, the flat surface of the fixed magnetic pole or the movable magnetic pole may be partially cut as long as it is substantially annular. Such an embodiment will be described below.

  Next, a solenoid according to a fifth embodiment of the invention will be described. FIG. 13 is a cross-sectional view of a solenoid according to a sixth embodiment of the present invention, where (A) is a state in which the movable magnetic pole is separated from the fixed magnetic pole, and (B) is a state in which the movable magnetic pole is attracted to the fixed magnetic pole. Indicates. In FIG. 13, 63 is a bottom surface, 68 is a convex part, and the other code | symbol shows the same thing as FIG. FIG. 14 is a cross-sectional perspective view of the movable magnetic pole of the solenoid according to the sixth embodiment of the present invention. In FIG. 14, 62 is a recessed part, 64 is an outer surface, 65 is an inner surface, 66 is an upper surface, 67 is a convex part, and other reference numerals are the same as those in FIGS. Furthermore, FIG. 15 is a cross-sectional perspective view of the fixed magnetic pole of the solenoid according to the sixth embodiment of the present invention. In FIG. 15, reference numeral 69 denotes a recessed portion, and other reference numerals are the same as those in FIGS. In addition, the part which is not shown in figure is the same as the solenoid which concerns on 1st Embodiment except the part demonstrated below.

  In this embodiment, as can be readily seen from FIG. 13, the concave and convex portions of the fixed magnetic pole and the movable magnetic pole are arranged in reverse. That is, as shown in FIG. 14, the flat surface 21 of the movable magnetic pole 20 is formed in an annular shape along the edge of the tip side surface of the movable magnetic pole 20, and is formed so as to be orthogonal to the central axis of the shaft 83. ing. In the region surrounded by the flat surface 21, a recessed portion 62 is formed in an annular shape. Further, a convex portion 67 is formed at the center of the concave portion 62 and in the vicinity thereof. As for the convex part 67, the opening part of the through-hole 30 is exposed in the center of the upper surface 66, and its vicinity. Further, the flat surface 21 and the upper surface 66 are disposed on the same virtual plane orthogonal to the central axis of the movable magnetic pole 20 and the shaft 83. Further, as shown in FIG. 15, the flat surface 41 of the fixed magnetic pole 40 is formed so as to be orthogonal to the central axis of the shaft 83 and faces the flat surface 21 of the movable magnetic pole 20. In the region surrounded by the flat surface 41, a convex portion 68 is formed in an annular shape. Further, a concave portion 69 is formed at the center of the convex portion 68 and in the vicinity thereof. The entire recess 69 is flat, and the opening of the through hole 50 is exposed at the center of the bottom surface 70 and in the vicinity thereof. Further, the flat surface 41 and the bottom surface 70 are arranged on the same virtual plane orthogonal to the central axis of the movable magnetic pole 20 and the shaft 83, and face the flat surface 21 and the upper surface 66 of the movable magnetic pole 40, respectively. ing.

  As described above, the concave portion 63 and the convex portion 67 of the movable magnetic pole 20 and the convex portion 68 and the concave portion 69 of the fixed magnetic pole 40 are in a relation reverse to that of the first embodiment. Further, since the magnetic flux flow substantially the same as that of the first embodiment is generated when the coil 86 is energized, the operational effects of this embodiment are also substantially the same as those of the first embodiment. However, in the first embodiment, the opening of the through hole 50 of the fixed magnetic pole 40 is exposed from the convex portion 46, whereas in this embodiment, the concave portion 69 is provided. Therefore, it can be said that the length of the movable magnetic pole 20 of the through-hole 50 and the length of the shaft 83 in the central axis direction is easier in the first embodiment. That is, in this embodiment, the lengths of the through holes 50 are not the same unless the length in the same direction is made longer than that in the first embodiment. The longer the length of the through hole 50, the longer the length of the sleeve 89 fitted into the inside. Therefore, since it is necessary to employ a long sleeve in a product that particularly requires the shaft 83 to have a small fluctuation (fluctuation), it can be said that it is advantageous to employ the configuration of the first embodiment.

  Furthermore, a solenoid according to a sixth embodiment of the present invention will be described. FIG. 16 is a cross-sectional perspective view of the movable magnetic pole of the solenoid according to the seventh embodiment of the present invention. In FIG. 16, reference numeral 74 denotes a convex portion, and other reference numerals are the same as those in FIGS. FIG. 17 is a cross-sectional perspective view of the fixed magnetic pole of the solenoid according to the seventh embodiment of the present invention. In FIG. 17, 72 is an outer surface, 73 is an inner surface, 78 is an inner surface, and 79 is an upper surface. In addition, the part which is not shown in figure is the same as the solenoid which concerns on 1st Embodiment except the part demonstrated below.

  In this embodiment, as shown in FIG. 16, a region closer to the center than the convex portion 74 of the movable magnetic pole 20 is used as the concave portion 23. In addition, as shown in FIG. 17, the region closer to the center than the recessed portion 57 of the fixed magnetic pole 40 is a convex portion 46. Therefore, when the coil 86 is energized, the convex portion 74 is inserted into the concave portion 57, and the convex portion 46 is inserted into the concave portion 23, the outer surface 26 and the outer surface 72, the inner surface 27 and the inner surface 73, In addition, the magnetic flux acting in the direction orthogonal to the direction in which the thrust is applied or a direction close to the direction orthogonal to the outer surface 34 and the inner surface 78 flows. What is characteristic in this embodiment is an inner surface 78, and this surface is both the inner surface of the recessed portion 57 and the outer surface of the convex portion 46. In other words, this embodiment can be said to have a concave portion and a convex portion provided in the intermediate configuration between the first embodiment and the third embodiment. Therefore, it is superior to the fifth embodiment of the present invention in both effects of increasing the thrust when the movable magnetic pole 20 and the fixed magnetic pole 40 are far from each other and reducing the thrust when they are close to each other. Further, since the opening of the through hole 50 of the fixed magnetic pole 40 is exposed from the convex portion 46, there is an advantage that a long sleeve can be adopted.

  Next, a solenoid according to a seventh embodiment of the present invention will be described. FIG. 18 is a cross-sectional perspective view of the movable magnetic pole of the solenoid according to the seventh embodiment of the present invention. In FIG. 18, 75a is a lower stage, 75b is an upper stage, 76 is a stepped surface, 77 is an outer surface, and other reference numerals are the same as those in FIGS. FIG. 19 is a cross-sectional perspective view of the fixed magnetic pole of the solenoid according to the seventh embodiment of the present invention. The reference numerals used in FIG. 18 are the same as those in FIGS. 4 and 11.

  In this embodiment, as shown in FIG. 18, in the convex portion 74 of the movable magnetic pole 20, the width of the upper step 75 b is narrower than the lower step 75 a and a step surface 76 is provided. Further, the convex portion 74 is higher than the convex portion 22, that is, extends toward the fixed magnetic pole 40 side from the convex portion 22. Further, the upper surface 25 and the step surface 76 are disposed on the same virtual plane orthogonal to the central axis of the movable magnetic pole 20 and the shaft 83. Further, as shown in FIG. 19, the recessed portion 42 is formed to have a width and a depth into which the protruding portion 74 can be inserted.

  Therefore, in this embodiment, when the coil 86 is energized and the movable magnetic pole 20 begins to approach the fixed magnetic pole 40, the inner side surface 78 of the convex portion 74 approaches the inner side surface 60 of the concave portion 42, and these surfaces A lot of magnetic flux begins to flow in between. However, since the outer surface 77 of the upper step 75b and the outer surface 59 of the recessed portion 42 are also separated by the width of the step surface 76, the flow of magnetic flux between them is small. Similarly, since the other opposing side surfaces are not so close to each other, the flow of magnetic flux is small. Therefore, when the movable magnetic pole 20 starts to approach the fixed magnetic pole 40, the effect of reducing the thrust is small. Further, when the movable magnetic pole 20 approaches the fixed magnetic pole 40, the outer surface 44 and the outer surface 26, the inner surface 45 and the inner surface 27, and the outer surface 59 and the outer surface 34 approach each other, and a large amount of magnetic flux is generated between them. Since it flows, the effect of thrust reduction is considerably increased. Focusing on the thrust, it can be said that the structure of this embodiment is obtained by connecting the configuration of the prior art and the configuration of the third embodiment in the direction of the central axis of the movable magnetic pole 20 and the shaft 83. Further, when the width of the stepped surface 76 is adjusted to bring the outer surface 77 closer to the outer surface 59, the configuration of the first embodiment and the configuration of the third embodiment can be combined with the movable magnetic pole 20 and the shaft 83. It becomes close to what is connected in the direction of the central axis.

  Further, an embodiment that focuses on adjusting the flow of magnetic flux that reduces thrust will be described below. 20A and 20B are explanatory views of a solenoid according to an eighth embodiment of the present invention, in which FIG. 20A is a sectional perspective view of a movable magnetic pole, FIG. 20B is a sectional perspective view of a fixed magnetic pole, and FIG. It is a perspective view which shows the modification of this. In FIG. 20, 90 is a cut, 91a, 91b, and 91c are ribs, and other reference numerals are the same as those in FIG.

  This embodiment substantially includes two further embodiments. As shown in FIG. 20 (A), the movable magnetic pole 20 of this embodiment forms a cut 90 in the convex portion 22 and further three similar cuts at intervals of 90 degrees in the circumferential direction of the convex portion 22, for a total of four. Forms a mosquito. When the fixed magnetic pole 40 of FIG. 7B is combined with the movable magnetic pole 20, the areas of the outer surface 26 and the inner surface 27 are reduced by the amount of the cut 90 and the like, so that the flow of magnetic flux that reduces thrust Can be made slightly smaller. Accordingly, there is an advantage that various thrust characteristics can be given to one ready-made product by appropriately forming such a cut in the movable magnetic pole of the ready-made solenoid.

  The fixed magnetic pole 40 of FIG. 20B is provided with a total of four ribs, ribs 91a, 91b and 91c, and ribs (not shown) at portions corresponding to the cuts 90 and the like of the movable magnetic pole 20. When the fixed magnetic pole 40 having such a rib is combined with the movable magnetic pole shown in FIG. 20A, the surface where the cut 90 is formed, that is, the surface facing the cut 90 is also the outer surface 26 and the inner side 27. Since it acts similarly, the flow of the magnetic flux which reduces thrust can be enlarged a little. Therefore, by adopting such a fixed magnetic pole, there is an advantage that a variety of thrust characteristics can be given to one ready-made product. Further, the number of cuts and ribs can be appropriately increased or decreased according to the required thrust characteristics. As shown in FIG. 20C, if the convex portion 22 is chamfered to be rounded, the area of the side surface of the convex portion 22 is further reduced, so that the thrust can be adjusted to various sizes.

  Next, a solenoid according to a ninth embodiment of the invention will be described. FIG. 21 is an explanatory view of a solenoid according to a ninth embodiment of the present invention, in which (A) is a cross-sectional perspective view of a movable magnetic pole, and (B) is a cross-sectional perspective view of a fixed magnetic pole. In FIG. 21, reference numerals 92a, 92b and 92c denote projecting portions, 93 denotes cuts and other reference numerals, which are the same as those in FIG. In this embodiment, as shown in FIG. 21 (A), a total of four projecting portions, ie, projecting portions 92a, 92b and 92c, and a projecting portion not shown are provided. Further, as shown in FIG. 21B, a total of four cuts such as a cut 93 are provided in accordance with the protrusions 92a, 92b and 92c. Therefore, the flat surface 21 of the movable magnetic pole 20 and the flat surface 41 of the fixed magnetic pole 40 are divided at four points. When the fixed magnetic pole 40 having such a cut and the movable magnetic pole shown in FIG. 20A are combined, these surfaces act in the same manner as the outer surface 26 and the inner surface 27, so that the thrust is adjusted to various sizes. it can

  As described above, in the solenoid 10 according to each embodiment of the present invention, the movable magnetic pole 20 is provided with the convex portion 22 (or the convex portion 22 and the convex portion 31), and the fixed magnetic pole 40 is provided with the concave portion 23 (or the concave portion). By providing another recessed portion in the portion 23, it does not contribute to the flow of magnetic flux acting in the direction in which the shaft 83 advances, that is, in the direction orthogonal to the direction of the thrust, or in the direction close to the direction orthogonal, that is, in the thrust. Alternatively, the thrust that rapidly increases as the movable magnetic pole 20 approaches the fixed magnetic pole 40 is suppressed by the flow of magnetic flux that generates a force that hardly contributes. Therefore, in the solenoid 10 according to each embodiment, an area where the thrust is larger than that of the solenoid 11 according to the prior art can be set as the control stroke area. Moreover, since it is not necessary to apply special processing to the movable magnetic pole 20 and the fixed magnetic pole 40, there is an advantage that the manufacturing cost is not greatly affected. Further, in the solenoid 10 according to the first and second embodiments, the same auxiliary magnetic pole 80, case 81, shaft 83, coil bobbin 85, coil 86, and lead wires 87a and 87b as the solenoid 11 can be used. Therefore, there is no need to make any special changes to the production equipment. It can also be preferably applied to a solenoid valve.

  The present invention is not limited to the contents described above, and the shape of the auxiliary magnetic pole, the internal structure of the case, the structure of the coil bobbin, or the shape of the shaft does not depart from the scope described in each claim. Various modifications can be made as long as they are. For example, an intermediate region formed of an inclined surface or a curved surface may be provided between the flat surface 21 and the convex portion 22 or between the flat surface 41 and the recessed portion 42. In addition, the auxiliary magnetic pole may be omitted if the thickness of the case is sufficient. Further, an auxiliary magnetic pole may be provided inside the case. In this case, for example, a magnetic flux can be generated between a part of the fixed magnetic pole and the auxiliary magnetic pole. Furthermore, the structure and shape of the movable magnetic pole in each embodiment may be combined as appropriate. In addition, the convex part of the movable magnetic pole or fixed magnetic pole is formed from a different base material from the other part, and the movable magnetic pole is formed by fitting the convex part into the annular groove formed in the large diameter part. May be.

DESCRIPTION OF SYMBOLS 10 Solenoid 11 Solenoid 20 Movable magnetic pole 21 Flat surface 22 Convex part 23 Concave part 24 Bottom surface 25 Upper surface 26 Outer side surface 27 Inner side surface 28 Large diameter part 29 Small diameter part 30 Through-hole 31 Convex part 32 Bottom surface 33 Upper surface 34 Outer side surface 35 Inner side surface 36 Notch groove 37 Convex portion 38 Top surface 39 Outer side surface 40 Fixed magnetic pole 41 Flat surface 42 Recessed portion 43 Bottom surface 44 Outer side surface 45 Inner side surface 46 Convex portion 47 Body portion 48 Top surface 50 Through hole 51a Screw hole 51b Screw hole 52 Edge 53 concave portion 54 upper surface 55 bottom surface 56 outer side surface 57 concave portion 58 bottom surface 59 outer side surface 60 inner side surface 61 upper surface 62 concave portion 63 bottom surface 64 outer side surface 65 inner side surface 66 upper surface 67 convex portion 68 convex portion 69 concave portion 70 bottom surface 71 upper surface 72 Outer side surface 73 Inner side surface 74 Convex part 75a Lower step 75b Upper step 76 Step surface 77 Outer side surface 78 Inner side surface 79 Upper surface 80 Auxiliary magnetic pole 8 Case 82 facing portion 83 the shaft 84 the threaded hole 85 the coil bobbin 86 coil 87a leads 87b leads 88 insulated cover 89 sleeve 90 cuts 91a rib 91b rib 91c rib 92a protruding portions 92b protruding portion 92c protruding portion 93 cut

Claims (8)

In a solenoid having a coil, a fixed magnetic pole provided in the vicinity of the coil, and a movable magnetic pole provided so as to be slidable and attracted to the fixed magnetic pole when energizing the coil,
The fixed magnetic pole includes, on the side facing the movable magnetic pole, a flat surface formed in an annular shape or a substantially annular shape, and a concave portion and a convex portion formed in a region surrounded by the flat surface. And any one of these convex parts is made to contain the other one,
The movable magnetic pole includes, on the side facing the fixed magnetic pole, a flat surface formed in an annular shape or a substantially annular shape, and a concave portion and a convex portion formed in a region surrounded by the flat surface. And the convex part includes the other, and the concave part and the convex part of the fixed magnetic pole have an inverse relationship between the internal part and the internal part. Has been made,
When the coil is energized, the convex part of the movable magnetic pole is inserted into the concave part of the fixed magnetic pole, and the concave part of the movable magnetic pole is inserted into the convex part of the fixed magnetic pole. A solenoid characterized by. The fixed magnetic pole has a through hole formed along a central axis, the convex portion is formed at and near the center of the concave portion, and one end of the through hole opens at the central portion of the convex portion and the vicinity thereof. And
The movable magnetic pole has a through hole formed along a central axis, the concave portion is formed at and near the center of the convex portion, and one end of the through hole opens at the central portion of the concave portion and the vicinity thereof. And
The bearing further includes a bearing fitted in the through hole of the fixed magnetic pole, and a shaft fitted in the through hole of the movable magnetic pole and slidably supported by the bearing. Item 2. The solenoid according to Item 1.   The distance from the bottom surface of the recessed portion to the flat surface and the distance from the bottom surface of the recessed portion to the tip of the convex portion are equal in the central axis direction of the fixed magnetic pole. 2. The solenoid according to 2.   The movable magnetic pole is characterized in that, in the central axis direction, the distance from the tip of the convex portion to the flat surface is equal to the distance from the tip of the convex portion to the bottom surface of the concave portion. The solenoid according to claim 2 or claim 3.   The fixed magnetic pole is further formed with another concave portion at and near the center of the convex portion, and the movable magnetic pole is opposed to the other concave portion of the fixed magnetic pole at and near the center of the concave portion, 5. The solenoid according to claim 2, further comprising another convex portion formed so as to be insertable into the another concave portion of the fixed magnetic pole. 6.   6. The solenoid according to claim 5, wherein the movable magnetic pole is formed with a step so that one or both of the convex portion and the other convex portion has a narrower width on the tip side.   7. The movable magnetic pole or the fixed magnetic pole has a cut that reaches the outer peripheral surface or the concave portion in the convex portion including the concave portion among the convex portions. Solenoid to any one of the items.   While being fixed to the movable magnetic pole, an auxiliary magnetic pole formed with a flat surface orthogonal to the operating direction of the movable magnetic pole, and part or all of the auxiliary magnetic pole is formed in a cylindrical shape, and the fixed magnetic pole is fitted, 8. The magnetic case according to claim 1, further comprising a magnetic case in which a flat surface opposite to the flat surface of the auxiliary magnetic pole is formed in the vicinity of the flat surface of the auxiliary magnetic pole. solenoid.

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