JP2005286234A - Linear solenoid valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a linear solenoid valve which can further improve absorbing force for a movable core. <P>SOLUTION: A coil 32 wound around a coil bobbin 30 is formed to have the square cross-section, an annular collar 39 is formed with a conic surface 38 in the side of external circumference and a concave portion 36 in the side of internal circumference to the end of a fixed core 24 provided opposing to the movable core 26. The annular collar 39 is allocated at the position of almost center area (almost L/2) for dividing the size L into almost two sizes along the axial line direction of a coil laminating layer body 33. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a linear solenoid valve capable of generating an electromagnetic force proportional to an energization amount to a solenoid portion and displacing a valve body by the electromagnetic force.

  2. Description of the Related Art Conventionally, an electromagnetic valve that displaces a valve body by attracting a movable iron core to a fixed iron core by an electromagnetic force generated under the excitation action of a solenoid coil has been used.

  As this type of electromagnetic valve, the applicant of the present application has proposed an electromagnetic device capable of obtaining accurate responsiveness to the magnetic force of the movable core, as shown in Patent Document 1, for example.

Registered Utility Model No. 2530268

  The present invention has been made in connection with the above proposal, and further improves the attractive force to the movable core by setting the positional relationship between the annular flange of the fixed core and the coil laminate laminated on the coil bobbin. An object of the present invention is to provide a linear solenoid valve that can be made to operate.

  In this section, for ease of understanding, the reference numerals in the accompanying drawings will be described in parentheses. However, the contents described in this section should not be construed as being limited to those given the reference numerals.

The present invention provides a linear solenoid valve that generates an electromagnetic force proportional to the energization amount to the solenoid portion and displaces the valve body by the electromagnetic force.
A valve body including a valve body (18) having an inlet port (56) and an outlet port (58) through which pressure fluid flows and a housing (14);
A coil laminate (33) formed by laminating a coil (32) wound around a coil bobbin (30) provided in the housing, and attracted to the fixed core (24) under an energizing action on the coil. A solenoid part (12) having a movable core (26);
A valve mechanism (16) having a valve body (66) that is provided on the valve body and switches between a communication state and a non-communication state of the inlet port and the outlet port by transmitting the displacement of the movable core;
With
At the end of the fixed core (24) facing the movable core (26), an annular flange (39) is formed by an outer peripheral conical surface portion (38) and an inner peripheral recess (36), The said annular collar part (39) is arrange | positioned in the approximate center part (substantially L / 2) along the axial direction of the said coil laminated body (33), It is characterized by the above-mentioned.

  According to the present invention, the annular flange is disposed at the substantially central portion (substantially L / 2) along the axial direction of the coil laminate, so that the magnetic field strength at the substantially central portion of the coil laminate is the strongest. In combination, it is presumed that the magnetic flux vector is rectified in the same direction toward the annular flange side in the flow of magnetic flux generated around the coil laminate.

  As a result, the attractive force (electromagnetic force) with respect to the movable core can be further improved by disposing the annular flange portion of the fixed core substantially at the center along the axial direction of the coil laminate.

  Further, according to the present invention, the end face of the movable core and the end face of the housing are substantially flush with each other, or the end face of the movable core is set to protrude outward from the end face of the housing.

  In other words, when the coil is not energized, a part of the side peripheral surface of the movable core and the side peripheral surface of the yoke connected to the bottom portion of the housing and the bottom portion are set to partially overlap each other. ing.

  In this case, the flow of magnetic flux generated under the energization action on the coil is not only the flow of magnetic flux flowing from the inner peripheral surface of the cylindrical yoke toward the side peripheral surface of the movable core via the bottom of the housing, A magnetic flux flowing from the inner peripheral surface of the portion corresponding to the bottom portion to the side peripheral surface of the movable core is formed via the bottom portion of the housing.

  Therefore, when the magnetic flux flows through the bottom of the housing toward the movable core, for example, the magnetic flux flows into the cylindrical yoke through the bottom of the housing, and then from the yoke toward the movable core. Compared with the magnetic circuit of the electromagnetic valve according to the related art constituted only by the magnetic flux flowing, in the present invention, the magnetic flux flows from the inner peripheral surface of the portion corresponding to the bottom of the housing toward the movable core side. The magnetic flux can be circulated very smoothly, and the amount of magnetic flux in the entire magnetic circuit, that is, the amount of magnetic flux can be increased. As a result, the suction force with respect to the movable core can be greatly improved.

  Furthermore, according to the present invention, the movable core is formed via the bottom portion of the housing by forming a tapered portion or an R portion having a circular arc shape in the inner wall of the housing that gradually decreases in diameter from the bottom side toward the yoke side. When the magnetic flux is circulated toward the side, the magnetic flux can be flowed more smoothly, and the amount of the magnetic flux that is circulated can be increased.

  Furthermore, according to the present invention, a shaft that is integrally displaced with the movable core is fixed to the movable core, and one end of the shaft is provided in the hole of the housing, and the shaft By adopting a double-end support structure in which the other end is slidably supported by the second bearing provided on the fixed core, stable straightness of the movable core is ensured.

  Furthermore, according to the present invention, the gap generated between the stacked coils can be made extremely small by making the cross-sectional shape of the coil wound around the coil bobbin square or rectangular. Therefore, the winding space of the coil wound around the coil bobbin can be reduced.

  According to the present invention, the following effects can be obtained.

  That is, by arranging the annular flange portion of the fixed core at a substantially central portion of the coil wound around the coil bobbin, the vector of the magnetic flux generated under the energization action on the coil is directed in the same direction toward the annular flange portion side. Rectified to increase the amount of magnetic flux, and the attractive force to the movable core can be further improved.

  Preferred embodiments of the linear solenoid valve according to the present invention will be described below and described in detail with reference to the accompanying drawings.

  In FIG. 1, reference numeral 10 indicates a hydraulic control valve according to an embodiment of the present invention.

  The hydraulic control valve 10 is formed in a bottomed cylindrical shape with a magnetic material such as SUM (JIS standard), for example, and has a housing 14 provided with a solenoid portion (linear solenoid portion) 12 therein, and the housing 14 is integrated with the housing 14. And a valve body 18 having a valve mechanism portion 16 provided therein. The housing 14 and the valve body 18 function as a valve main body.

  The housing 14 includes a cylindrical portion 15 on the outer peripheral side, a cylindrical yoke 22 formed at a predetermined interval on the inner peripheral side of the cylindrical portion 15 and disposed substantially parallel to the cylindrical portion 15, and the cylindrical portion. 15. A bottom portion 17 that is thicker than 15 and joins the cylindrical portion 15 and the yoke 22, and a cross section that continues to the bottom portion 17 and projects outward by a predetermined length along the axial direction of the housing 14 The cylindrical portion 15, the yoke 22, the bottom portion 17, and the protruding portion 19 are integrally formed. For example, the cylindrical yoke 22 is configured to press-fit a substantially cylindrical yoke formed separately from the housing 14 to a press-fit surface formed on the inner peripheral surface of the bottom portion 17 of the housing 14. Also good.

  The inner wall of the housing 14 where the outer cylindrical portion 15 and the inner yoke 22 face each other has an inclined surface that is inclined at a predetermined angle from the bottom 17 side toward the yoke 22 side in the cross section. A tapered portion 21 that gradually decreases in diameter toward the yoke 22 side is provided. Instead of the tapered portion 21, as shown in FIG. 4, it may be configured as an R portion 21a formed by an arc portion having a predetermined radius of curvature.

  A hole 52 is formed in the inner central portion of the protrusion 19 so as to face one end of a shaft 46 to be described later. Further, a flat housing end surface 23 is formed on the outer surface of the housing 14 so as to be continuous with the skirt portion of the projection 19, and as shown in FIG. 3, the end surface 26 a of the movable core 26 on the projection 19 side and the aforementioned The housing end surface 23 is provided so as to be substantially flush with each other.

  The solenoid unit 12 includes a coil assembly 20 accommodated in the housing 14 and a cylindrical shape that is integrally formed with the housing 14 on the closed end side of the housing 14 and disposed inside the coil assembly 20. A yoke 22, a fixed core 24 that is coupled to the opening end of the housing 14 and is disposed along the axial direction inside the coil assembly 20 with a predetermined clearance from the yoke 22, the yoke 22, And a movable core 26 slidably fitted to the fixed core 24.

  The coil assembly 20 is formed of a synthetic resin material and has a coil bobbin 30 having flanges 28a and 28b at both end portions along the axial direction, and is wound around the coil bobbin 30 a plurality of times. As shown, the coil 32 is formed of a square wire formed in a square cross section.

  The entire coil having a substantially rectangular cross section in which the coil 32 is laminated on the coil bobbin 30 will be described below as a coil laminate 33.

  By forming the coil 32 to have a square cross section, contact between the coils 32 wound around the coil bobbin 30 becomes surface contact. Therefore, the coil 32 is stably and aligned at a predetermined position. Thereby, as FIG. 6 shows, the one flange 28a (28b) of the coil bobbin 30 can be made unnecessary. By eliminating the one flange 28a (28b), the axial dimension of the entire solenoid portion 12 is shortened, and the size can be reduced.

  In addition, when a coil according to the related art formed in a circular cross section as shown in FIG. 14 is wound around a coil bobbin, a force that collapses toward the flange acts due to the tension when winding the coil. In the coil 32 having a square cross section, the force that collapses toward the flange 28a (28b) due to the surface contact between the coils 32 does not work, so that one flange 28a (28b) can be dispensed with.

  As shown in FIGS. 7 and 8, another coil 32 a made of a flat wire formed in a rectangular cross section may be used. In this case, the coil 32 formed in a square cross section can be set with a smaller winding space than the coil 32a formed in a rectangular cross section. Furthermore, in the coil 32 having a square cross section, since the peripheral dimension of the cross section can be reduced as compared with the coil 32a having a rectangular cross section, the cross-sectional area of the insulating coating on the coil 32 can be set small.

  The yoke 22 and the fixed core 24 that are spaced apart from each other by a predetermined distance are formed on the outer peripheral surface of the annular vertical surface portion 34 formed on one end surface of the cylindrical yoke 22 and the concave portion 36 of the fixed core 24. A conical surface portion 38 is provided. A tapered portion 35 for reducing leakage magnetic flux is chamfered in the circumferential direction on one end surface of the yoke 22 adjacent to the vertical surface portion 34.

  The yoke 22 and the fixed core 24 are formed with a cylindrical portion and a recess 36 corresponding to the shape of the movable core 26, and the movable core 26 is slid between the cylindrical yoke 22 and the recess 36 of the fixed core 24. A linear solenoid structure to be moved can be used.

  At the end of the fixed core 24 facing the movable core 26, there is provided an annular flange 39 having a substantially triangular cross section formed by a conical surface portion 38 on the outer peripheral side and a concave portion 36 on the inner peripheral side. In this case, the center reference line C of the annular flange 39 integrally formed at the end of the fixed core 24 is a position (substantially L / L) of the dimension L along the axial direction of the coil laminate 33. 2) (see FIG. 3).

  Between the housing 14 and the coil 32, there is provided a resin sealing body 40 that molds the outer peripheral surface of the coil 32 and a part of the coil bobbin 30, and the resin sealing body 40 is a coupler portion that energizes the coil 32. 42 is integrally formed of resin material. The coupler portion 42 is provided so that the terminal portion 44a of the terminal 44 electrically connected to the coil 32 is exposed.

  By covering the outer peripheral surface of the coil 32 with the resin sealing body 40, the coil 32 can be stably protected. Further, when the flange 28a (28b) formed at one end of the coil bobbin 30 is not necessary, the unnecessary portion of the flange 28a (28b) is covered with the resin sealing body 40, thereby further increasing the coil. 32 is stably protected.

  A shaft 46 penetrating the central portion of the movable core 26 is fixed to the movable core 26, and one end portion of the shaft 46 is a first flat bearing (first bearing) mounted in the hole 52 of the protrusion 19 of the housing 14. A second plain bearing (second bearing) is slidably supported in the axial direction via 48 a, and the other end of the shaft 46 is mounted in a through hole 50 that penetrates the center of the fixed core 24. It is supported so as to be slidable in the axial direction via 48b.

  The movable core 26 and the shaft 46 are integrally coupled by crimping one end portion and the other end portion along the axial direction of the movable core 26 to which the shaft 46 is attached to deform inward in the radial direction. . In addition, the movable core 26 and the shaft 46 may not be configured separately, and the movable core 26 may be integrally formed including the shaft 46.

  Thus, the movable core 26 can be made into a both-ends support structure via the 1st and 2nd flat bearings 48a and 48b which respectively support the both ends of the shaft 46 which penetrates. By making the shaft 46 have a both-ends support structure, it is possible to ensure stable straightness of the movable core 26.

  The first flat bearing 48a is press-fitted and fixed in the hole 52 of the protrusion 19 of the housing 14, and the first flat bearing 48a is connected to the outer peripheral surface of the first flat bearing 48a in the axial direction communicating between both end faces. A groove 54a is formed. The second flat bearing 48b is press-fitted and fixed to the inner peripheral surface of the through hole 50, and the second flat bearing 48b is connected to the outer peripheral surface of the second flat bearing 48b in the axial direction through the second communication groove 54b. Is formed.

  A ring body 55, which is formed of a nonmagnetic material and functions as a spacer for preventing residual magnetism in the solenoid portion 12, is provided on the end surface of the movable core 26 facing the fixed core 24 via the shaft 46.

  That is, residual magnetism is generated in the fixed core 24 or the movable core 26 when the energization of the solenoid unit 12 is interrupted, and the movable core 26 may not be separated from the fixed core 24 under the action of the residual magnetism. By providing the ring body 55 via the shaft 46, a predetermined clearance is formed between the fixed core 24 and the occurrence of residual magnetism can be suppressed.

  The movable core 26 may be made of, for example, ferritic stainless steel such as SUS410L or SUS405 (JIS standard), general steel such as S10C (JIS standard), or free-cutting steel material such as SUM (JIS standard). .

  The valve mechanism 16 includes a valve body 18 having an inlet port 56, an outlet port 58, a drain port 60, and a breather port 62 communicating with an oil tank (not shown) on the side, and a space inside the valve body 18. The part 64 has a spool valve (valve element) 66 disposed so as to be displaceable along the axial direction.

  In the spool valve 66, a first land portion 66a, a second land portion 66b, and a third land portion 66c are formed in this order from the solenoid portion 12, and the first land portion 66a and the second land portion 66b are the same. The third land portion 66c is formed to have a diameter slightly smaller than the first and second land portions 66a and 66b.

  A space portion 64 of the valve body 18 is closed by an end block 68, and a return spring that constantly presses the spool valve 66 toward the solenoid portion 12 between the end block 68 and the spool valve 66. 70 is disposed. The return spring 70 is not limited to a coil spring, and may be constituted by an elastic body including a leaf spring (not shown), for example.

  The end surface of the spool valve 66 adjacent to the solenoid portion 12 is provided so as to contact the end surface of the shaft 46, and the spring force of the return spring 70 is applied to the movable core 26 via the spool valve 66 and the shaft 46. Thus, the movable core 26 is in a state of being pressed toward the direction of the arrow X1 in FIG.

  The hydraulic control valve 10 according to the embodiment of the present invention is basically configured as described above. Next, the operation and effects thereof will be described.

  When the solenoid unit 12 is not energized (OFF state), as shown in FIG. 1, the spool valve 66 is pressed in the direction of arrow X <b> 1 in FIG. 1 by the spring force (pressing force) of the return spring 70. In this state, the communication between the inlet port 56 and the outlet port 58 is blocked.

  Therefore, by energizing a power source (not shown) and energizing the coil 32, the solenoid unit 12 is excited and turned on, and an electromagnetic force (attraction force) is generated by the magnetic circuit 82 as shown in FIG. In this case, an electromagnetic force proportional to the amount of current supplied to the coil 32 is generated, and the electromagnetic force is applied to the movable core 26. Therefore, when the spool valve 66 is displaced in the direction of the arrow X2 against the pressing force of the return spring 70 under the action of the electromagnetic force, the communication between the drain port 60 and the outlet port 58 is blocked, The inlet port 56 and the outlet port 58 communicate with each other (see FIG. 2).

  Accordingly, the pressure oil supplied from a hydraulic source (not shown) is supplied to a hydraulic operating device (not shown) through the inlet port 56 and the outlet port 58 via a passage (not shown). When the energization to the solenoid unit 12 is stopped, the solenoid unit 12 is turned off and returned to the initial position shown in FIG.

  In the present embodiment, the center reference line C of the annular flange 39 of the fixed core 24 is set to a position (substantially L / 2) that substantially bisects the dimension L along the axial direction of the coil laminate 33. Thus, as shown in FIG. 10, the amount of magnetic flux flowing in the magnetic circuit 82 (the amount of magnetic flux) can be increased.

  That is, coupled with the fact that the magnetic field strength at the substantially central portion of the coil laminated body 33 is the strongest, as shown in FIG. 10, in the flow of magnetic flux generated around the coil laminated body 33 having a rectangular cross section. This is because the magnetic flux vector is rectified in the same direction toward the annular flange 39 by disposing the annular flange 39 that functions as a suction portion at the approximate center of the linear portion excluding the corner portion. It is guessed.

  As a result, by disposing the annular flange 39 of the fixed core 24 substantially at the center along the axial direction of the coil laminate 33, the attractive force (electromagnetic force) to the movable core 26 can be further improved. When the suction force is the same, the overall configuration of the hydraulic control valve 10 can be reduced in size.

  Further, in the present embodiment, when the coil 32 is not energized, as shown in FIG. 1, a part of the side peripheral surface of the movable core 26, the bottom portion 17 of the housing 14, and the yoke 22 connected to the bottom portion 17. Are set so that the end surface 26a of the movable core 26 and the housing end surface 23 are substantially flush with each other.

  In this case, the flow of magnetic flux generated under the energization action on the coil 32 flows from the inner peripheral surface of the cylindrical yoke 22 through the bottom 17 of the housing 14 to the side periphery of the movable core 26 as shown in FIG. In addition to the flow of magnetic flux flowing toward the surface (see the magnetic flux A in FIG. 10), the movable core 26 side also from the inner peripheral surface of the portion corresponding to the bottom portion 17 via the bottom portion 17 of the housing 14. A flow of magnetic flux (refer to magnetic flux B in FIG. 10) flowing toward the peripheral surface is formed.

  Therefore, when the magnetic flux flows through the bottom portion 17 of the housing 14 toward the movable core 26, for example, after the magnetic flux flows into the cylindrical yoke 22 via the bottom portion 17 of the housing 14, the yoke 22 Compared with a magnetic circuit (not shown) of a solenoid valve according to the prior art constituted only by the magnetic flux A flowing from the movable core 26 toward the movable core 26 side, this embodiment corresponds to the bottom 17 of the housing 14. Since the magnetic flux B flows from the inner peripheral surface of the part toward the movable core 26 side, the magnetic flux can be circulated extremely smoothly and the magnetic flux 82 in the entire magnetic circuit 82, that is, the magnetic flux amount ( Magnetic flux A + magnetic flux B) can be increased.

  As a result, the suction force with respect to the movable core 26 can be greatly improved, and the overall structure of the hydraulic control valve 10 can be reduced in the case of the same suction force.

  It should be noted that the end surface 26a of the movable core 26 and the housing end surface 23 are not limited to a substantially flush position, and the end surface 26a of the movable core 26 is removed from the housing end surface 23 by ΔT, as shown in FIG. By providing so as to protrude toward the side (projection 19 side), the amount of magnetic flux flowing from the inner peripheral surface of the portion corresponding to the bottom 17 of the housing 14 toward the movable core 26 side is further increased. Is preferred.

  Furthermore, in the present embodiment, the tapered portion 21 that gradually decreases in diameter from the bottom 17 side toward the yoke 22 side is formed on the inner wall of the housing 14 where the outer cylindrical portion 15 and the inner yoke 22 face each other. By forming the R portion 21a having an arcuate cross section, it is possible to flow the magnetic flux more smoothly when flowing the magnetic flux toward the movable core 26 via the bottom portion 17 of the housing 14, and the flowing magnetic flux. The amount can be increased.

  That is, since the intersecting portion (inner surface of the connecting portion) between the cylindrical yoke 22 and the bottom portion 17 of the housing 14 is tapered or rounded toward the movable core 26 side, the coil stack having a rectangular cross section is formed. It is presumed that the flow of the circular magnetic flux generated by the body 33 is closer to the ideal shape.

  For example, in the comparative example in which a right angle portion is formed on the inner surface of the intersection of the yoke 22 and the bottom portion 17 of the housing 14, as shown in FIG. In contrast, in the present embodiment, as shown in FIG. 11, the magnetic flux flowing out from the bottom 17 side of the housing 14 is directed toward the yoke 22 via the taper portion 21 (R portion 21a). It will flow smoothly.

  In the vicinity of the taper portion 21 or the R portion 21a, the vector of the magnetic flux is rectified in the same direction toward the movable core 26 side which is the magnetic flux delivery side, so that the movable core 26 side is smoother. It is possible to circulate the magnetic flux in the air and to increase the amount of the magnetic flux that circulates.

  Furthermore, since the area of the inner peripheral surface of the bottom portion 17 corresponding to the side peripheral surface of the movable core 26 is increased by providing the tapered portion 21 or the R portion 21a, the magnetic path formation area is increased and the amount of magnetic flux is further increased. Can be increased.

  As a result, the suction force with respect to the movable core 26 can be improved, and when the suction force is the same, the overall structure of the hydraulic control valve 10 can be reduced in size. For example, as shown in FIG. 13 showing the relationship between the stroke and the thrust of the movable core 26, the tapered portion 21 is formed compared to the characteristic curve M (see the broken line) when the tapered portion 21 is not formed. It can be understood that the thrust of the characteristic curve N (see solid line) in the case of increasing is increased.

  Furthermore, in the present embodiment, the cross-sectional shape of the coil 32 wound around the coil bobbin 30 constituting the solenoid unit 12 is made square or rectangular so that the gap generated between the stacked coils 32 is extremely small. Can do. Therefore, for example, when compared with a conventional technique in which a solenoid coil having a circular cross section has the same number of turns, the total cross sectional area of the coil 32 (the entire space of the coil 32 wound around the coil bobbin 30) can be set small. .

  Paradoxically, this means that the ratio of the conductor cross-sectional area tightened in the winding space of the coil 32, that is, the conductor occupation ratio, can be set larger than that of the circular cross-section. Therefore, since the winding space of the coil 32 can be reduced, the shape of the coil bobbin 30 can be reduced, and ultimately the solenoid unit 12 as a whole can be reduced in size.

  Further, for example, when the winding space is the same as that of the solenoid coil having a circular cross section, in the present embodiment using the coil 32 having a square cross section, the number of turns on the coil bobbin 30 can be increased. The attraction force (electromagnetic force) generated at 12 can be increased.

  Furthermore, since the winding space of the coil 32 can be reduced, the continuous total dimension (full length) of the coil 32 can be reduced. Therefore, the resistance value of the coil 32 can be reduced, and the power consumption consumed when the coil 32 is energized can be suppressed.

  For example, when the coil 32 having a circular cross section is formed so as to have the same resistance value as that of the coil having a circular cross section, in the present embodiment, the number of windings around the coil bobbin 30 can be set to a large value. Electromagnetic force) can be improved.

  Furthermore, since the contact surface between the laminated coils 32 is a surface contact, the single-line occupancy in the winding space can be set larger than that of the coil having a circular cross section.

  Therefore, the gap generated between the stacked coils 32 can be made extremely small, and the occupation density of each coil 32 per unit volume of the winding space can be improved. Thereby, the heat conductivity (heat dissipation) in a winding space can be improved. For example, when applied to an electromagnetic valve that is used in an environment where the ambient temperature is lower than the coil heat generation temperature, the heat dissipation is improved. Therefore, in addition to the fact that the resistance value of the coil 32 can be set small as described above, further energization Heat generation in the coil 32 during heat generation can be reduced, and therefore the resistance value can be further reduced.

  Furthermore, the solenoid part 12 including the coil 32 formed in a square cross section can be suitably applied as a vehicle-mounted solenoid valve. In-vehicle components are generally limited to a minimum applied voltage (for example, 8 V) by a battery voltage. And since it is requested | required as a vehicle-mounted solenoid valve to ensure the minimum magnetomotive force (electric current value), for example, when the same magnetic circuit is used, a maximum resistance value will be decided inevitably. Here, since the resistance value of the coil 32 generally increases as the temperature of the coil 32 increases, the maximum resistance value must be a value that also takes into account the increased resistance value. For example, if the maximum resistance value is set without taking this rising resistance value into consideration, the necessary current value cannot be obtained, and the minimum magnetomotive force may not be obtained. That is, when used as an in-vehicle solenoid valve, it is necessary to secure a magnetomotive force (current value) even if the resistance value of the coil 32 is energized through the solenoid unit 12 and the temperature of the coil 32 is increased.

  Therefore, if the resistance value of the coil 32 and the resistance value of the coil 32 during energization heat generation are low, a high current value can be secured by Ohm's law, which is extremely beneficial. That is, by making the cross-sectional shape of the coil 32 square, for example, in the solenoid unit 12 that can obtain the same magnetomotive force, the resistance value of the coil 32 is reduced to reduce power consumption. The amount of heat generated by the coil 32 during energization decreases, and the resistance value during energization heat generation can be reduced.

  As a result, since the resistance value of the coil 32 during energization heat generation can be reduced to ensure a high current value, it can be suitably used as an in-vehicle electromagnetic valve in which the minimum applied voltage is limited. Further, for example, the solenoid unit 12 having the coil 32 having a square cross section compared to other solenoid units having the same minimum magnetomotive force constituted by coils having a circular cross section has a current value that can be increased. Since the number of turns on the coil bobbin 30 can be reduced, further downsizing can be achieved.

It is a longitudinal cross-sectional view along the axial direction of the hydraulic control valve which concerns on embodiment of this invention. It is a longitudinal cross-sectional view which shows the state which the spool valve displaced by exciting the solenoid part of the hydraulic control valve shown in FIG. It is a partial expanded longitudinal cross-sectional view of the coil assembly which comprises the said hydraulic control valve. FIG. 5 is a partially enlarged longitudinal sectional view of an R portion having a circular arc shape formed in a portion where a bottom portion of a housing and a yoke are connected to each other. It is the partial expanded longitudinal cross-sectional view by which the coil of the cross-sectional square was wound by the coil bobbin. It is a partial expanded longitudinal cross-sectional view which shows the state from which the flange formed in the coil bobbin was removed. It is a partial expanded longitudinal cross-sectional view which concerns on the modification of the coil assembly shown in FIG. FIG. 5 is a partially enlarged longitudinal sectional view in which a coil having a rectangular cross section is wound around a coil bobbin. It is a partial expanded longitudinal cross-sectional view which shows the state which protruded outward only (DELTA) T rather than the housing end surface from the end surface of the movable core. It is a partially omitted enlarged explanatory view showing a magnetic circuit formed in a solenoid part. FIG. 5 is a partially omitted enlarged explanatory view showing magnetic flux flowing through a tapered portion formed at a portion where a bottom portion of a housing and a yoke are connected to each other. It is a partially omitted enlarged explanatory view showing a magnetic flux flowing through a right angle portion according to a comparative example. It is a characteristic view which shows the relationship between the thrust of a movable core, and a stroke. It is the partial expanded longitudinal cross-sectional view by which the coil which concerns on a prior art was wound by the coil bobbin.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Hydraulic control valve 12 ... Solenoid part 14 ... Housing 16 ... Valve mechanism part 17 ... Bottom part 18 ... Valve body 19 ... Projection part 20 ... Coil assembly 21 ... Tapered part 21a ... R part 22 ... Yoke 23 ... Housing end surface 24 ... Fixed core 26 ... movable cores 28a, 28b ... flange 30 ... coil bobbins 32, 32a ... coil 33 ... coil laminate 34 ... vertical surface portion 36 ... concave portion 38 ... conical surface portion 39 ... annular flange 40 ... resin sealing body 46 ... shaft 48a 48b ... Plain bearing 50 ... Through hole 54a, 54b ... Communication groove 56 ... Inlet port 58 ... Outlet port 64 ... Space 66 ... Spool valve 70 ... Return spring 82 ... Magnetic circuit

Claims (6)

In the linear solenoid valve that generates an electromagnetic force proportional to the energization amount to the solenoid portion and displaces the valve body by the electromagnetic force,
A valve body including a valve body and a housing having an inlet port and an outlet port through which pressure fluid flows; and
A coil stack formed by stacking coils wound around a coil bobbin provided in the housing; a movable core attracted by a fixed core under an energizing action on the coil; and surrounding an outer peripheral surface of the movable core A solenoid having a cylindrical yoke that
A valve mechanism provided on the valve body and having a valve body that switches between a communication state and a non-communication state of the inlet port and the outlet port by transmitting the displacement of the movable core;
With
At the end of the fixed core facing the movable core, an annular flange is formed by an outer peripheral conical surface portion and an inner peripheral recess, and the annular flange is along the axial direction of the coil stack. A linear solenoid valve characterized by being arranged at a substantially central portion. The valve of claim 1, wherein
The end surface of the movable core facing the housing is set to be substantially flush with the housing end surface formed on the outer surface of the housing, or the end surface of the movable core is directed outward from the housing end surface. A linear solenoid valve that is set to protrude. The valve according to claim 2,
The housing includes a bottom portion having the housing end surface, and an inner wall portion where the bottom portion and the yoke are connected has a tapered portion that gradually decreases in diameter from the bottom portion toward the yoke side, or an R portion having an arcuate cross section. A linear solenoid valve is formed. The valve of claim 1, wherein
A shaft that penetrates along the axial direction of the movable core and is displaced integrally with the movable core is fixed to the movable core, and one end of the shaft is slidably supported by a first bearing provided in the housing. And the other end of the shaft is slidably supported by a second bearing provided on a fixed core. The valve of claim 1, wherein
The linear solenoid valve according to claim 1, wherein the coil has a square cross section. The valve of claim 1, wherein
The linear solenoid valve according to claim 1, wherein the coil has a rectangular cross section.

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