JP2007321822A - Electromagnetic drive mechanism and fluid control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic drive mechanism for compatibly attaining improved controllability and improved productivity. <P>SOLUTION: The electromagnetic drive mechanism comprises a movable element 16 to be reciprocatively moved, a stator 10 having a cylindrical supporting hole 14 for slidably supporting the movable element 16 at its outer periphery, and a coil energized to generate a magnetic flux passing through the movable element 16 and the stator 10, which drives the element 16. The element 16 has a non-magnetic layer 18 whose outer periphery is shaped in regular polygon, and a magnetic body 17 whose outer periphery is covered with the non-magnetic layer 18. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electromagnetic drive device and a fluid control device including the same.

  2. Description of the Related Art Conventionally, in a fluid control device or the like that controls a fluid, an electromagnetic drive device that generates a magnetic flux passing through a mover and a stator by energizing a coil to drive the mover is widely used. As one type of such an electromagnetic drive device, a device that slides and supports a mover from the outer peripheral side by a support hole of a stator is disclosed in Patent Document 1 and the like.

By the way, in the conventional device disclosed in Patent Document 1 or the like, the magnetic body of the mover is covered with a nonmagnetic layer. Therefore, even if the radial gap between the support hole and the mover is locally reduced due to the mover being eccentric with respect to the support hole, the magnetic gap between the support hole and the magnetic body is nonmagnetic. The layer portion can be secured, and an increase in force (hereinafter referred to as side force) for pressing the mover into the support hole can be suppressed. As the side force increases, the sliding resistance between the support hole and the mover also increases, so the hysteresis of the move position of the mover increases with respect to the amount of current supplied to the coil, and the controllability of the move position is increased. Will fall.
JP 2002-222710 A

  In the conventional device disclosed in Patent Literature 1 and the like, the outer peripheral shape of the nonmagnetic layer is circular, and therefore the location where the mover is eccentrically contacted with the support hole is arbitrary in the circumferential direction of the mover. Therefore, in order to precisely manage the radial gap between the support hole and the nonmagnetic layer to realize desired sliding characteristics, it is necessary to reduce the dimensional tolerance on the entire circumference of the nonmagnetic layer. In addition, in order to obtain desired sliding characteristics between the support hole and the nonmagnetic layer, it is necessary to manage the surface roughness over the entire circumference of the nonmagnetic layer. Such a necessity is undesirable because it is a factor that deteriorates productivity and increases costs.

  An object of the present invention is to provide an electromagnetic drive device that achieves both improved controllability and improved productivity, and a fluid control device including the same.

  According to the first aspect of the present invention, since the outer peripheral shape of the nonmagnetic layer covering the outer peripheral side of the magnetic body in the mover is a regular polygonal shape, the nonmagnetic layer is in contrast to the cylindrical support hole of the stator. Contact is made at the corner of the regular polygon. Therefore, in order to achieve a desired sliding characteristic by finely managing the radial gap between the support hole and the nonmagnetic layer, it is only necessary to reduce the dimensional tolerance only for the corners of the nonmagnetic layer. Further, in order to obtain a desired sliding characteristic between the support hole and the nonmagnetic layer, it is only necessary to manage the surface roughness only for the corners of the nonmagnetic layer. As described above, since the requirements regarding the dimensional tolerance and the surface roughness need only be satisfied by a part of the nonmagnetic layer, the productivity can be improved. As described above, according to the first aspect of the present invention, it is possible to achieve both improvement in the position controllability of the mover by realizing desired sliding characteristics and improvement in productivity.

  According to the second aspect of the present invention, the outer peripheral shape of the magnetic main body is a regular polygon having a concentric and similar reduction relationship with respect to the outer peripheral shape of the nonmagnetic layer. Magnetic properties are determined by the average outer diameter of the magnetic body. Here, since the outer diameter at the corner of the regular polygon of the magnetic body is larger than the average outer diameter, the corner of the magnetic body is set while setting the average outer diameter of the magnetic body so as to obtain desired magnetic characteristics. The thickness of the nonmagnetic layer can be reduced on the outer peripheral side. Moreover, since the outer peripheral shape of the magnetic main body and the nonmagnetic layer is a regular polygonal shape having a concentric and similar reduction relationship, the thickness of the nonmagnetic layer becomes substantially uniform over the entire periphery. The thickness can be reduced over the entire circumference.

  According to the third aspect of the invention, the movable member is reciprocated together with the movable member of the electromagnetic driving device according to the first or second aspect, so that a desired sliding is achieved between the support hole of the electromagnetic driving device and the movable member. It is possible to improve the position controllability of the mover and the movable member by expressing the characteristics. According to the third aspect of the present invention, since the fluid flowing through the fluid port is controlled by the reciprocating movement of the movable member, the controllability of the fluid can be improved by improving the position controllability of the movable member. .

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a fluid control apparatus according to an embodiment of the present invention. The fluid control device 1 controls the hydraulic pressure of hydraulic fluid supplied to, for example, a hydraulic control device for a vehicle automatic transmission.

  In the fluid control device 1, the linear solenoid 2 includes a fixed core 10, a yoke 15, a movable core 16, a resin molded body 20, a coil 24, and the like.

  The fixed core 10 is formed in a cylindrical shape from a magnetic material such as iron, and includes a housing portion 11, a suction portion 12, and a magnetoresistive portion 13. The accommodating portion 11 has a support hole 14 that slides and supports the movable core 16 from the outer peripheral side in a cylindrical hole shape. The suction part 12 is provided with a gap in the axial direction with respect to the housing part 11. The attraction unit 12 generates a magnetic attraction force between the movable core 16 to attract the movable core 16 in the axial direction. The magnetoresistive portion 13 is provided between the accommodating portion 11 and the attracting portion 12 and is formed thinner than the respective portions 11 and 12. The magnetic resistance unit 13 suppresses leakage of magnetic flux between the housing unit 11 and the suction unit 12.

  The yoke 15 is formed in a cylindrical shape by a magnetic material such as iron and accommodates the fixed core 10 and the coil 24 on the inner peripheral side. Both end portions of the yoke 15 are magnetically connected to the housing portion 11 and the suction portion 12 of the fixed core 10.

  The movable core 16 is disposed substantially coaxially on the inner peripheral side of the fixed core 10 and can reciprocate in the axial direction. The movable core 16 is a composite formed by covering the outer peripheral side of the magnetic main body 17 with a nonmagnetic layer 18. Here, the magnetic body 17 is formed in a column shape from a magnetic material such as iron. The nonmagnetic layer 18 is formed in a cylindrical shape from a nonmagnetic material such as NiP or resin.

  The resin molded body 20 has a bobbin portion 21 and a connector portion 22. The bobbin portion 21 is disposed on the outer peripheral side of each portion 11, 12, 13 of the fixed core 10. A coil 24 is wound around the outer peripheral side of the bobbin portion 21. A terminal 23 for supplying electric power from the outside to the coil 24 is embedded in the connector portion 22.

  When electric power is supplied from the terminal 23 to the coil 24, a magnetic flux that passes through the magnetic body 17 of the fixed core 10, the yoke 15, and the movable core 16 is generated, and between the suction portion 12 of the fixed core 11 and the magnetic body 17. Magnetic attraction works. Here, the magnetic attraction force increases as the energization current to the coil 24 increases. Due to the generation of such a magnetic attractive force, the movable core 16 is driven in a direction (in this case, the left direction in FIG. 1) from the accommodating portion 11 side toward the attractive portion 12 side in the reciprocating direction.

  In the fluid control device 1, the spool valve 4 includes a sleeve 30, a spool 36, an elastic member 42, and the like.

  The sleeve 30 is formed in a cylindrical shape and slidably supports the spool 36 from the outer peripheral side. An input port 32, an output port 33, a feedback port 34, and a discharge port 35 are formed in the sleeve 30 so as to penetrate in the radial direction. The hydraulic fluid supplied from the tank (not shown) side is input to the input port 32. The output port 33 outputs hydraulic oil to the output side of a hydraulic control device or the like of the automatic transmission. The output port 33 and the feedback port 34 communicate with each other outside the fluid control apparatus 1, and part of the hydraulic oil output from the output port 33 is input to the feedback port 34. The discharge port 35 discharges hydraulic oil to the tank side.

  The spool 36 is formed in a skewer shape, and is disposed substantially coaxially on the inner peripheral side of the sleeve 30 so as to be reciprocally movable in the axial direction. One end portion of the spool 36 is in contact with the end portion of the movable core 16 on the suction portion 12 side. Therefore, the force acting on the spool 36 by driving the movable core 16 according to the energization of the coil 24 is a thrust force that presses the spool 36 to the opposite side (here, the left direction in FIG. 1).

  The spool 36 has lands 37, 38, and 39 that are slidably supported by the sleeve 30. The amount of hydraulic fluid flowing from the input port 32 to the output port 33 is determined by the axial length of the overlap margin between the inner peripheral portion 30 a of the sleeve 30 and the land 38 between the ports 32 and 33. Specifically, in the present embodiment, the elements 30 and 36 are configured such that the amount of hydraulic oil from the input port 32 to the output port 33 increases as the overlap margin between the inner peripheral portion 30a and the land 38 is shorter. The amount of hydraulic oil flowing from the output port 33 to the discharge port 35 is determined by the axial length of the overlap margin between the inner peripheral portion 30 b of the sleeve 30 and the land 37 between the ports 33 and 35. Specifically, in the present embodiment, the elements 30 and 36 are configured such that the amount of hydraulic oil from the output port 33 to the discharge port 35 increases as the overlap margin between the inner peripheral portion 30b and the land 37 is shorter.

  A feedback chamber 40 communicating with the feedback port 34 is formed between the lands 38 and 39. Since the pressure receiving areas receiving the hydraulic pressure of the feedback chamber 40 in the lands 38 and 39 are different from each other, the force acting on the spool 36 by the hydraulic pressure of the feedback chamber 40 becomes a thrust force that presses the spool 36 to the opposite side to the movable core 16.

  The elastic member 42 is formed of a compression coil spring, and is disposed on the opposite side of the movable core 16 with the spool 36 interposed therebetween. One end of the elastic member 42 is locked by a retainer 43 fixed to the sleeve 30, and the other end of the elastic member 42 is locked by a land 37 of the spool 36. The urging force that acts on the spool 36 due to the elastic deformation of the elastic member 42 becomes a thrust force that presses the spool 36 toward the movable core 16 (here, in the right direction in FIG. 1).

  With the above configuration, the spool 36 moves to a position where the thrust force generated by driving the movable core 16, the thrust force generated by the hydraulic pressure in the feedback chamber 40, and the thrust force generated by elastic deformation of the elastic member 42 are balanced. Therefore, when the movable core 16 is driven by the increase in the energization current of the coil 24 and the spool 36 moves to the elastic member 42 side (here, the left direction in FIG. 1), the inner peripheral portion 30a of the sleeve 30 and the land 38 While the overlap margin becomes longer, the overlap margin between the inner peripheral portion 30b of the sleeve 30 and the land 37 becomes shorter. As a result, the amount of hydraulic fluid from the input port 32 to the output port 33 decreases, while the hydraulic fluid flow rate from the output port 33 to the discharge port 35 increases, so the hydraulic pressure of the hydraulic fluid output from the output port 33 decreases. . On the other hand, when the spool 36 moves to the movable core 16 side due to a decrease in the energization current to the coil 24, the overlap margin between the inner peripheral portion 30a and the land 38 is shortened, while the overlap between the inner peripheral portion 30b and the land 37 is reduced. The bill gets longer. As a result, the amount of hydraulic fluid from the input port 32 to the output port 33 increases, while the hydraulic fluid flow rate from the output port 33 to the discharge port 35 decreases, so the hydraulic pressure of the hydraulic fluid output from the output port 33 increases. .

  Next, the movable core 16, which is a characteristic part of the linear solenoid 2, will be described with reference to FIG.

  The magnetic main body 17 of the movable core 16 has an outer peripheral wall 50 whose contour shape is a regular octagonal shape. In the magnetic main body 17, the eight corners 52 of the outer peripheral wall 50 are located on the outer peripheral side of the virtual circle C <b> 1 in FIG. 2 schematically representing the average outer diameter of the outer peripheral wall 50. That is, the outer diameter of each corner 52 is larger than the average outer diameter of the outer peripheral wall 50.

  The nonmagnetic layer 18 of the movable core 16 has an outer peripheral wall 60 whose contour shape is a regular octagonal shape. In the present embodiment, the nonmagnetic layer 18 is formed so that the contour shape of the outer peripheral wall 50 of the magnetic body 17 is concentric and similar to the contour shape of the outer peripheral wall 60 of the nonmagnetic layer 18. . Thereby, the thickness in the radial direction of the nonmagnetic layer 18 is made substantially uniform over the entire circumference. Note that the virtual circle C2 in FIG. 2 in which the eight corners 62 of the outer peripheral wall 60 are inscribed in the nonmagnetic layer 18 has a larger diameter than the virtual circle C1.

  In the linear solenoid 2 having such characteristics, the radius of the virtual circle C2 inscribed by each corner 62 of the nonmagnetic layer 18 is set to be approximately equal to the outer diameter of the nonmagnetic layer 18 in the conventional device disclosed in Patent Document 1 and the like. Thus, the amount of eccentricity of the movable core 16 with respect to the support hole 14 can be ensured to the same extent as in the conventional device. In addition to setting the radius of the virtual circle C2, the average outer diameter of the outer peripheral wall 50 of the magnetic body 17 (here, the radius of the virtual circle C1) is substantially equal to the outer diameter of the columnar magnetic body in the conventional apparatus. By setting, the same magnetic properties as those of the conventional device can be expressed between the magnetic body 17 and the fixed core 10. Moreover, since the outer diameter of each corner 52 of the magnetic body 17 is larger than the average outer diameter of the outer peripheral wall 50, the nonmagnetic layer 18 between the corner 52 and each corner 62 of the nonmagnetic layer 18 is made thinner. can do. Here, since the non-magnetic layer 18 has a substantially uniform thickness over the entire circumference, the non-magnetic layer 18 can be thinned over the entire circumference to reduce the cost.

  Further, in the linear solenoid 2, when the movable core 16 is decentered with respect to the support hole 14 as shown in FIG. 2, at least one of the eight corners 62 of the nonmagnetic layer 18 (in the figure) In the example, two are in line contact with the cylindrical support hole 14. On the other hand, the eight plane portions 64 (see FIG. 2) between the corner portions 62 in the nonmagnetic layer 18 cannot contact the support hole 14 in any eccentric form. Therefore, in order to realize a desired sliding characteristic by finely managing the radial gap between the support hole 14 and the nonmagnetic layer 18, the dimensional tolerance should be reduced only for each corner 62 of the nonmagnetic layer 18. That's fine. Further, in order to obtain a desired sliding characteristic between the support hole 14 and the nonmagnetic layer 18, it is only necessary to manage the surface roughness only for each corner 62 of the nonmagnetic layer 18.

  As described above, according to the linear solenoid 2, it is only necessary to satisfy the requirements regarding the dimensional tolerance and the surface roughness in a part of the nonmagnetic layer 18, so that the productivity can be improved and the cost can be reduced. Further, according to the linear solenoid 2, since the contact area between the support hole 14 and the nonmagnetic layer 18 is reduced as compared with the conventional device, the nonmagnetic layer 18 can be supported by meeting the requirements regarding dimensional tolerance and surface roughness. The sliding resistance between the hole 14 and the nonmagnetic layer 18 can be reduced. Therefore, according to the fluid control device 1 including the linear solenoid 2, the moving positions of the movable core 16 and the spool 36 can be controlled with high accuracy, so that the hydraulic pressure controllability of hydraulic oil based on the position control of the spool 36 is improved. can do.

  In the embodiment described above, the linear solenoid 2 corresponds to the “electromagnetic drive device” recited in the claims, the movable core 16 corresponds to the “movable element” recited in the claims, and the fixed core. 10 corresponds to the “stator” recited in the claims. The output port 33 corresponds to a “fluid port” described in the claims, the sleeve 30 corresponds to a “port forming member” described in the claims, and the spool 36 described in the claims. Corresponds to “movable member”.

  Although one embodiment of the present invention has been described so far, the present invention is not construed as being limited to these embodiments, and can be applied to various embodiments without departing from the scope of the present invention. Can do.

  For example, the contour shape of the outer peripheral walls 50 and 60 of the magnetic body 17 and the nonmagnetic layer 18 may be at least a regular polygonal shape, for example, a regular hexagonal shape as shown in FIG. . Moreover, about the outline shape of the outer peripheral walls 50 and 60 of the magnetic main body 17, shapes other than a regular polygon shape, for example, a circular shape as shown in FIG.3 (b) may be sufficient.

  Furthermore, the present invention can be applied not only to the fluid control device 1 including the linear solenoid 2 but also to various mechanical devices including the electromagnetic driving device, the electromagnetic driving device as a single unit, and the like.

It is sectional drawing which shows the fluid control apparatus by one Embodiment of this invention. It is the II-II sectional view taken on the line of FIG. It is sectional drawing which shows the modification of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fluid control apparatus, 2 Linear solenoid (electromagnetic drive device), 4 Spool valve, 10 Fixed core (stator), 11 Housing | casing part, 12 Attraction | suction part, 13 Magnetoresistive part, 14 Support hole, 16 Movable core (mover) , 17 Magnetic body, 18 Non-magnetic layer, 24 Coil, 30 Sleeve (port forming member), 32 Input port, 33 Output port (fluid port), 34 Feedback port, 35 Discharge port, 36 Spool (movable member), 50 Wall, 52 corners, 60 outer peripheral wall, 62 corners, 64 planes, C1 virtual circle, C2 virtual circle

Claims (3)

A reciprocating mover;
A stator having a cylindrical support hole for slidingly supporting the mover from the outer peripheral side;
A coil for generating magnetic flux passing through the mover and the stator by energization to drive the mover;
In an electromagnetic drive device comprising:
2. The electromagnetic drive device according to claim 1, wherein the movable element has a nonmagnetic layer whose outer peripheral shape is a regular polygonal shape, and a magnetic body whose outer peripheral side is covered with the nonmagnetic layer.   2. The electromagnetic driving device according to claim 1, wherein the outer peripheral shape of the magnetic main body is a regular polygonal shape having a concentric and similar reduction relationship with respect to the outer peripheral shape of the nonmagnetic layer. The electromagnetic drive device according to claim 1 or 2,
A port forming member forming a fluid port;
A movable member that controls fluid flowing through the fluid port by reciprocating with the mover;
A fluid control apparatus comprising:

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