JP2005351447A - Solenoid valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To smoothly displace a shaft member in the axial direction by sufficiently securing the axial length of a retainer supporting the shaft member of a proportional solenoid valve to reduce the radial clearance of the retainer. <P>SOLUTION: In a bearing 53, a plurality of, for example, six (not shown) spherical holes 45 are bored in a cylindrical retainer 56 at a roughly axial center position, and balls 57 are rotatably supported on the holes 45. When the axial length of the retainer 56 is set to at least one to two times the inner diameter of the retainer 56, and the wall thickness of the retainer 56 is set to at least 0.6 to 0.9 times the diameter of the balls 57, the axial length can be sufficiently secured and the radial clearance of a rod 54 is reduced, and a plane passing the center of the balls 57 can be positioned vertically to the axial direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electromagnetic valve that controls a pressurized fluid by displacing a spool in accordance with an applied current, and more specifically, prevents the cage of a bearing mechanism that supports a rod from tilting, and moves the bearing mechanism in an axial direction. The present invention relates to an improvement in a solenoid valve that can be operated smoothly.

The solenoid valve is a shaft member formed integrally with the movable iron core, for example, the rod is slidably supported by bearing members having both ends. In this case, in order to smoothly operate the rod, it is important that the ball holder that holds the ball can be displaced in the axial direction.
Conventionally, in this type of solenoid valve, bearing members 11 and 11 (both of the symbols described in Patent Document 1) that support both ends 3a and 3b of the plunger 3 are composed of a ball, a ball holder, and a pair of springs. Each end of the spring of the bearing member 11, 11 is a permanent magnet 12, one end of the ball holder and the other end of the ball holder, one end of the plunger 3 or the other end of the plunger 3, one end of the ball holder and the other end of the ball holder, The movement of the bearing members 11 and 11 in the axial direction is restricted in contact with the blind plug 10 (reference numeral described in Patent Document 1) (for example, see Patent Document 1).
Further, the other solenoid valve is a stopper mechanism that restricts the bearings 24 and 25 (both of the symbols described in Patent Document 2) that support the shaft 23 (the symbols described in Patent Document 2) from moving in the axial direction. A structure of reference numerals 35 and 36 described in Patent Document 2 is provided (see, for example, Patent Document 2).
Further, in the other solenoid valve, the retainer 28 of the spherical body 27 that supports the shaft 6 (both of the symbols described in Patent Document 3) has a short length in the axial direction, so that the retainer 28 is easily inclined with respect to the shaft 6. (For example, refer to Patent Document 3).
Japanese Utility Model Publication No. 61-139370 Japanese Utility Model Publication No. 1-106682 Japanese Utility Model Publication No. 4-129984

However, the electromagnetic valve described in Patent Document 1 is difficult to assemble because the amount of bending of the four springs is amplified, and the structure is complicated.
The electromagnetic valve described in Patent Document 2 needs to be provided with a stopper to restrict the bearing from moving in the axial direction. For this reason, it becomes long in the axial direction.
In the electromagnetic valve described in Patent Document 3, the plane formed by the sphere supporting the shaft tends to be inclined with respect to the shaft, and the sphere cannot operate smoothly, which causes a malfunction.
The present invention has been made to solve the above-described problems, and ensures a sufficient length in the axial direction of the cage that supports the shaft member of the solenoid valve, and reduces the radial gap of the cage. Accordingly, an object of the present invention is to provide an electromagnetic valve that can smoothly displace the shaft member in the axial direction.

In order to achieve the above object, according to the present invention, a solenoid is disposed on the outer periphery of a housing and a yoke, a fitting hole is formed in an adapter mounted on the housing and the yoke, and the fitting hole is inserted into the fitting hole. In a solenoid valve having a bearing mechanism that supports both ends of the rod and cooperates with the rod,
The bearing mechanism is
A cylindrical holding member inserted into the fitting hole of the housing and the adapter;
A spherical member rotatably inserted in a spherical recess disposed in the circumferential direction on the holding member;
With
The holding member has a length in the axial direction, and a normal line formed by the center of the spherical member is formed with a small inclination with respect to the axial direction by reducing a radial gap with respect to the rod. It is characterized by.
According to the present invention, since the inclination of the plane formed by the center of the spherical member set by the spherical member can be reduced, the bearing mechanism can be smoothly displaced in the axial direction, and the structure is simple. An inexpensive solenoid valve can be provided.
In this case, it is preferable that the length of the holding member in the axial direction is at least 1 to 2 times the inner diameter of the holding member because the inclination of the cage can be reduced.
Furthermore, if the thickness of the holding member is at least 0.6 to 0.9 times the diameter of the spherical member, it is preferable because the radial gap can be reduced.

  The present invention can reduce the inclination of the plane passing through the center of the spherical member set by the spherical member, so that the bearing mechanism can be smoothly displaced in the axial direction, and the structure is simple and inexpensive. Can be provided.

A proportional solenoid valve 40 according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a schematic structure of a proportional solenoid valve 40 according to an embodiment of the present invention. FIG. 2 is an enlarged detail view of the bearings 53 and 54.
The proportional solenoid valve 40 includes a housing 41 that is a magnetic metal material, and the housing 41 includes a cylindrical portion 42 and a flange portion 43. A fitting hole 44 is formed through the housing 41 in the axial direction. A cylindrical yoke 46 made of a magnetic material is coaxially disposed facing the cylindrical portion 42 of the housing 41. The cylindrical portion 42 functions as a fixed iron core.

  A solenoid 47 is disposed on the outer periphery of the housing 41 and the yoke 46. The solenoid 47 is covered with a magnetic material cover 48 around which a coil 47b is wound around a bobbin 47a. The yoke 46 is in contact with one end of the solenoid 47, a large diameter portion 46a of the yoke 46 is integrated by a cover 48, and an adapter 49 is mounted in the inner hole of the stepped portion 46b. A nonmagnetic end cover 50 is in contact with one end of the yoke 46, and one end of the cover 48 is fixed to the end cover 50. A hole 51 is formed in the yoke 46 coaxially with the fitting hole 44 of the housing 41, and a movable iron core 52 is loosely fitted in the hole 51 so as to be displaceable in the axial direction. A non-magnetic spacer 52 a is fixed to the movable iron core 52 on the fixed iron core 42 side. The spacer 52 a functions as a stopper that restricts the movement of the movable iron core 52, and prevents the movable iron core 52 from being adsorbed to the fixed iron core 42. A bearing 53 is fitted into the fitting hole 44 so as to be slidable in the axial direction, and the bearing 53 supports one end of a rod 54. The other end of the rod 54 is supported by a bearing 55 that is fitted in the fitting hole 49a of the adapter 49 so as to be slidable in the axial direction.

  Reference numeral 60 denotes a sleeve, which is integrated with the housing 41 by, for example, crimping one end of the cover 48 in contact with the housing 41. A sleeve hole 61 is formed in the sleeve 60 coaxially with the fitting hole 44, and a spool 62 is slidably inserted into the sleeve hole 61. In the sleeve hole 61, a tank passage 63 that communicates a tank (not shown) and the sleeve hole 61 in order from the housing 41, a control passage 64 that communicates an actuator (not shown) and the sleeve hole 61, and a pump and sleeve hole 61 (not shown). And a tank passage 66 that connects a tank (not shown) and the sleeve hole 61 to each other.

In the spool 62, a first land portion 67 and a second land portion 68 are formed along the axial direction at an interval, and the land portion 67, 68 is interposed between the land portions 67, 68. An annular groove 69 communicating with one end of 68 is defined. The annular groove 69 is formed in the axial direction of the outer peripheral surface of the spool 62.
Further, a communication hole 70 is formed in the annular groove 69 in the axial radial direction, the communication hole 70 communicates with a guide hole 71 formed in the axial direction, and a piston 72 slides in the guide hole 71. It is freely inserted. The guide hole 71 has a function of a feedback chamber 71a that generates a feedback force in the direction of arrow X by the pressure in the guide hole 71.

The piston 72 is moved by an oil pressure (not shown), and the pressure in the control passage 64 is guided from the communication hole 70 to the feed bag chamber 71a. As a result, the piston 72 is displaced in the direction of the arrow Y, and one end thereof abuts against the adjuster 73. In the state where the piston 72 inserted into the spool 62 is pressurized and the piston 72 is in contact with the adjuster 73, a feedback force is applied to the spool 62 in the arrow X direction by the hydraulic pressure in the feedback chamber 71a. This is a well-known technique.
The spool 62 has a distribution chamber for distributing hydraulic oil supplied to a supply passage 65 from a pump (not shown) to a control passage 64 and a tank passage 66 by an annular groove 69. When the spool 62 is displaced in the axial direction, the gap communicating from the supply passage 65 to the control passage 64 and the gap communicating from the control passage 64 to the tank passage 66 change, and the output pressure of the control passage 64 changes.

FIG. 2 is an enlarged detailed view showing a schematic structure of the bearings 53 and 55. Since the bearings 53 and 55 have the same structure, only the bearing 53 will be described. The bearing 53 has a cylindrical retainer (holding member) 56 provided with a plurality of, for example, six (not shown) spherical holes (recesses) 45 in the circumferential direction at the approximate center in the axial direction. Balls (spherical members) 57 are axially supported by the holes 45 in a single row.
Further, six balls 57 are arranged in the circumferential direction of the cage 56, but if at least three balls 57 are equally arranged in the circumferential direction, the rod 54 may be stably supported.
In this case, the cage 56 has a length in the axial direction set at least 1 to 2 times the inner diameter of the cage 56, and the thickness of the cage 56 is at least 0.6 with respect to the diameter of the ball 57. When set to .about.0.9 times, a sufficient length in the axial direction is secured, the gap in the axial radial direction with respect to the rod 54 is reduced, and the plane passing through the center of the ball 57 is substantially perpendicular to the axial direction. be able to. Thereby, the inclination in the axial direction of the plane passing through the center of the ball 57 can be reduced, and the bearing 53 can be smoothly displaced in the axial direction in cooperation with the rod 54.
Further, a part of the spherical surface of the ball 57 protrudes from the inner and outer peripheral surfaces of the cage 56. Accordingly, in a state where the bearing 53 is inserted into the fitting hole 44 and the rod 54 is inserted into the inner hole of the cage 56 of the bearing 53, a part of the spherical surface of the ball 57 protrudes from the hole 45 and the fitting hole 44. Can be engaged with the inner peripheral surface and the outer peripheral surface of the rod 54, and can move in the arrow Y direction or the arrow X direction corresponding to the displacement of the rod 54.

The proportional solenoid valve 40 according to the embodiment of the present invention is basically configured as described above. Next, the operation thereof will be described.
In FIG. 1, the proportional electromagnetic valve 40 controls the current value to be passed through the coil 47 b of the solenoid 47, thereby adjusting the electromagnetic force that pushes the spool 62 in the arrow Y direction with the rod 54. This electromagnetic force and the feedback chamber 71 a The spool 62 is moved in the axial direction to a position where the three forces of the force that pushes the spool 62 in the direction of the arrow X by the control pressure introduced to the spring and the elastic force that the spring member 74 pushes the spool 62 in the direction of the arrow X are balanced. Thereby, the control pressure of the control passage 64 is adjusted. As a result, a control pressure corresponding to the current value supplied to the coil 47b of the solenoid 47 is obtained.
Although the present invention has been described with respect to the proportional solenoid valve 40, it can also be applied to ordinary solenoid valves.

It is a longitudinal section showing a schematic structure of a solenoid valve concerning an embodiment of the invention. It is a longitudinal cross-sectional view which shows schematic structure of the bearing of FIG.

Explanation of symbols

40 Proportional solenoid valve 41 Housing 42 Cylindrical portion 44 Fitting hole 46 Yoke 47 Solenoid 49 Adapter 52 Movable iron core 53, 55 Bearing 56, 58 Cage 57, 59 Ball 60 Sleeve 62 Spool

Claims (3)

A solenoid is disposed on the outer periphery of the housing and the yoke, and fitting holes are formed in the adapter attached to the housing and the yoke. The fitting holes are inserted into the fitting holes to support both ends of the rod and cooperate with the rod. In a solenoid valve with a moving bearing mechanism,
The bearing mechanism is
A cylindrical holding member inserted into the fitting hole of the housing and the adapter;
A spherical member rotatably inserted in a spherical recess disposed in the circumferential direction on the holding member;
With
The holding member has a length in the axial direction, and a radial normal to the rod is reduced, so that a normal line of the plane formed by the center of the spherical member is formed with a small inclination with respect to the axial direction. A solenoid valve characterized by that. The solenoid valve according to claim 1, wherein
The length of the holding member in the axial direction is at least 1 to 2 times the inner diameter of the holding member. In the solenoid valve according to claim 1 or 2,
The solenoid valve according to claim 1, wherein the thickness of the holding member is at least 0.6 to 0.9 times the diameter of the spherical member.

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