JP4673831B2 - solenoid valve - Google Patents

Description

  The present invention relates to an electromagnetic valve that opens and closes a flow path by moving a valve body forward and backward with respect to a valve seat member.

  In general, a device that controls the flow of fluid, such as an antilock brake device for a vehicle, is provided with a normally closed solenoid valve or a normally open solenoid valve as appropriate. Conventionally, as such an electromagnetic valve, a movable core provided with a valve body, a valve seat member that blocks a flow path by contact with the valve body, and a spring for moving the movable core forward and backward with respect to the valve seat member A device including a fixed core and a coil is known (see Patent Document 1).

  Specifically, the normally closed solenoid valve disclosed in Patent Document 1 has a structure in which a spring is disposed between the fixed core and the movable core, and the movable core is always biased toward the valve seat member by the spring. It has become. For this reason, in this normally closed solenoid valve, when the valve core and the valve seat member come into contact with each other by the biasing force of the spring, the flow path is closed, and the movable core is attracted by a fixed core that is appropriately excited by a coil. In addition, the valve body is separated from the valve seat member, and the flow path is opened. In this normally closed solenoid valve, in order to communicate the front space and the rear space in the moving direction of the movable core, a communication groove communicating with the front and rear spaces is formed on the outer peripheral surface of the movable core. As a result, when the normally closed solenoid valve changes from the open state to the closed state, the liquid between the valve body and the valve seat member smoothly escapes from the communication groove, and the movement of the movable core is smooth.

  Further, the normally open solenoid valve has a fixed core integrally provided with a valve seat member, and a spring is disposed between the fixed core and the movable core, and the movable core is always moved from the valve seat member by this spring. It is structured to be separated. Therefore, in this normally open type electromagnetic valve, when the valve core and the valve seat member are separated by the biasing force of the spring and the flow path is opened in a normal state, the movable core is attracted by a fixed core that is appropriately excited by a coil. In addition, the valve body comes into contact with the valve seat member and the flow path is closed. And also in this normally open type solenoid valve, like the normally closed type solenoid valve, a communication groove that connects the front and rear spaces of the movable core is formed, so that when the state is changed from the open state to the closed state, The liquid between the valve seat members smoothly escapes from the communication groove, and the movable core moves smoothly.

JP-A-7-291111 (FIG. 5)

  However, in the prior art, since the movable core moves smoothly, there is a problem that when the electromagnetic valve is closed, the valve body and the valve seat member suddenly collide with each other, and abnormal noise is generated.

  Then, this invention makes it a subject to provide the solenoid valve which can suppress generation | occurrence | production of the abnormal noise by the collision with a valve body and a valve seat member.

The present invention that solves the above problems includes a valve seat member, a valve body member that advances and retreats so as to be able to come into contact with the valve seat member, a housing that slides on the valve body member and guides the advance and retreat operation of the valve body member, An electromagnetic valve comprising: a front portion of the valve body member on the valve seat member side; and a communication portion that communicates a rear space on the opposite side of the front space of the valve body member, wherein the valve body member is When moving to the valve seat member side, the flow path through which the fluid pushed out from between the valve body member and the valve seat member gradually narrows as the valve body member moves, and the communication portion A throttle portion that has a channel cross-sectional area smaller than the channel cross-sectional area is formed between the valve body member and the housing .

  According to the present invention, when the valve body member is moved toward the valve seat member when the valve is closed, the fluid between the valve body member and the valve seat member is pushed out toward the communicating portion by the valve body member. At this time, the flow path of the fluid gradually narrows with the movement of the valve body member and becomes a flow path cross-sectional area smaller than the flow path cross-sectional area of the communication portion, so that the fluid can smoothly escape to the communication portion. Therefore, the fluid temporarily stays between the valve body member and the valve seat member and functions as a damper. Therefore, a sudden collision between the valve body member and the valve seat member is suppressed, and generation of abnormal noise is suppressed.

  As a specific example, the valve body member is formed in a stepped shape in which a portion on the valve seat member side has a small diameter, and a groove as the communication portion is formed on an outer peripheral surface thereof. Around the small diameter portion of the body member, there is provided a flow path forming portion that faces the large diameter portion of the valve body member in the traveling direction of the valve body member, and the flow path is a large diameter portion of the valve body member. And the flow path forming part.

  According to this, when the valve body member is moved to the valve seat member side when the valve is closed, the large-diameter portion of the valve body member approaches the flow path forming portion, so that the flow path between them gradually increases. It narrows. As a result, the fluid cannot smoothly escape to the communicating portion, so that it temporarily stays between the valve body member and the valve seat member and functions well as a damper, and the above-described effects can be exhibited well. .

  The present invention also provides an elastic member for urging the valve body member toward the valve seat member, and a fixed core and a coil for separating the valve body member from the valve seat member against the urging force of the elastic member. The electromagnetic valve according to the present invention is particularly suitable when used in a normally closed electromagnetic valve.

  According to this, when the excitation of the fixed core by the coil is released when the valve is closed, the valve body member tends to move toward the valve seat member side by the elastic force of the elastic member. The momentum can be suppressed by the damper effect by the narrowing flow path. Therefore, even in an electromagnetic valve that is particularly susceptible to abnormal noise such as a normally closed electromagnetic valve, a sudden collision between the valve body member and the valve seat member is suppressed, and generation of abnormal noise can be suppressed.

  According to the present invention, the fluid between the valve body member and the valve seat member functions as a damper due to the flow path that gradually narrows as the valve body member moves, so that a difference caused by a collision between the valve body member and the valve seat member is caused. Generation of sound can be suppressed.

[First Embodiment]
Next, a first embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the drawings to be referred to, FIG. 1 is a longitudinal sectional view showing a normally closed electromagnetic valve according to the first embodiment, and FIG. 2 is a transverse sectional view showing a structure of a movable core. In the present embodiment, a case where the present invention is applied to a normally closed solenoid valve will be described.

  As shown in FIG. 1, a normally closed electromagnetic valve 1 is a valve for switching between closing and opening of a flow path R formed in a base B such as an antilock brake device, and mainly includes a housing 2 and a fixed core. 3, the coil unit 4, the valve body member 5, and the valve seat member 6 are comprised.

  The housing 2 includes a substantially cylindrical guide tube 21 and a substantially bottomed cylindrical body portion 22.

  The guide tube 21 has a cylindrical main body portion 21a, and also has an enlarged portion 21b having a larger diameter than the main body portion 21a formed to expand from the lower end (end on the body portion 22 side) of the main body portion 21a. have. The fixed core 3 is fixed to the main body portion 21a of the guide cylinder 21 by fitting and welding, and the body portion 22 is fixed to the expanding portion 21b by fitting and welding.

  The body part 22 is formed in a substantially bottomed cylindrical shape by a cylindrical side wall part 22a and a bottom wall part 22b. The side wall portion 22 a is formed with a predetermined thickness that is thicker than the thickness of the guide tube 21, so that the inner surface of the upper end portion 22 c (open end portion) is inside the inner surface of the main body portion 21 a of the guide tube 21. Is located. That is, the movable core 5 and the upper end portion 22c face each other because the inner surface of the upper end portion 22c comes inward from the inner surface of the main body portion 21a. Further, the side wall portion 22a has a first bulging portion 22d bulging outward from the top, a plurality of through holes 22e communicating in the radial direction inside and outside the body portion 22, and a second bulging bulging inward. A portion 22f is formed. The first bulging portion 22d is fixed to the base B, and the valve seat member 6 is fixed to the second bulging portion 22f by press-fitting. The bottom wall portion 22b is formed with one through hole 22g communicating with the inside and outside of the body portion 22 in the vertical direction.

  A filter 23 is provided below the first bulging portion 22d of the body portion 22 so as to cover the plurality of through holes 22e formed in the side wall portion 22a, whereby foreign matter entering the body portion 22 is provided. Intrusion is suppressed.

  The fixed core 3 is excited by the coil unit 4 to suck the valve body member 5 away from the valve seat member 6. Specifically, the fixed core 3 has a cylindrical main body portion 31 formed with substantially the same diameter as the inner peripheral surface of the main body portion 21a of the guide tube 21 and a substantially same diameter as the outer peripheral surface of the main body portion 21a of the guide tube 21. And a columnar enlarged diameter portion 32 formed by The main body 31 of the fixed core 3 is fixed to the main body 21 a of the guide cylinder 21 by fitting and welding. In this state, the outer peripheral surface of the enlarged diameter portion 32 is the main body 21 a of the guide cylinder 21. It is substantially flush with the outer peripheral surface.

  The coil unit 4 excites the fixed core 3, and includes a bobbin 41 surrounding the guide cylinder 21, a coil 42 wound around the bobbin 41, and a yoke that magnetically couples both ends of the guide cylinder 21. 43. In the coil unit 4, a current is appropriately passed through the coil 42 to generate a magnetic field from the coil 42 to excite the fixed core 3.

  The valve body member 5 includes a movable core 51 that can move forward and backward with respect to the valve seat member 6 and a valve body 52 that is fixed to the movable core 51.

  The movable core 51 is formed in a substantially cylindrical shape, and is formed in a stepped shape in which a lower portion (portion seat member 6 side portion) has a small diameter. Specifically, the movable core 51 includes a large diameter part 51 a and a small diameter part 51 b, the large diameter part 51 a is in sliding contact with the main body part 21 a of the guide cylinder 21, and the small diameter part 51 b is the upper end part of the body part 22. It arrange | positions through the predetermined clearance gap from the inner surface of 22c. Therefore, the large diameter part 51 a faces the upper end part 22 c of the body part 22 in the advancing / retreating direction (vertical direction) of the movable core 51, and the small diameter part 51 b is surrounded by the upper end part 22 c of the body part 22.

  In addition, on the outer peripheral surface of the movable core 51, communication grooves 51c that communicate from the upper surface of the large-diameter portion 51a to the lower surface of the small-diameter portion 51b are evenly arranged in three circumferential directions as shown in FIG. Is formed. Furthermore, a substantially cylindrical valve body holding portion 51d protruding downward is formed on the lower surface of the small diameter portion 51b. A spring mounting hole 51e is provided on the upper surface of the large-diameter portion 51a for disposing a return spring RS that biases the movable core 51 toward the valve seat member 6 side.

  By forming the movable core 51 in this way, an annular first flow path R1 is formed between the small diameter part 51b and the body part 22, and an annular first channel R1 is formed between the large diameter part 51a and the body part 22. Two flow paths R2 are formed, and a third flow path R3 is formed between the communication groove 51c and the guide cylinder 21. Moreover, since the large diameter part 51a has opposed the upper end part 22c of the body part 22, as for the 2nd flow path R2, as the movable core 51 advances and retreats, the flow path cross-sectional area gradually reduces or expands. It is like that. Here, the upper end portion 22c of the body portion 22 constituting a part of the second flow path R2 in which the flow path cross-sectional area changes corresponds to the flow path forming section.

  The flow path cross-sectional area of the second flow path R2 is configured to be smaller than the flow path cross-sectional area of the communication groove 51c at least when the movable core 51 is positioned at the lowest point (when the valve is closed). Yes. As a result, the second flow path R2 functions as a restriction (orifice).

  The valve body 52 is a member formed in a spherical shape, and is fixed in a valve body holding portion 51 d formed on the lower surface of the movable core 51. And the valve body 52 fixed to the lower surface of the movable core 51 in this way is freely contactable with the valve seat member 6 as the movable core 51 advances and retreats.

  The valve seat member 6 is a member formed in a bottomed cylindrical shape, and is fixed to the second bulging portion 22f of the body portion 22 by press-fitting so that the opening thereof faces downward. The bottom wall 61 of the valve seat member 6 is formed with a tapered valve seat surface 62 with which the valve body 52 abuts and a through hole 63 penetrating from the valve seat surface 62 into the valve seat member 6. Has been.

  Next, the operation of the normally closed solenoid valve 1 according to the present embodiment will be described with reference to FIGS. 1 and 3. In the drawings to be referred to, FIG. 3 is a perspective view (a) showing the flow of liquid when the normally closed solenoid valve starts to close from the open state, and shows the flow of liquid just before finishing the closing of the normally closed solenoid valve. It is a perspective view (b) shown. Note that in FIG. 3, the stroke amount of the movable core 51 and the like are expressed larger than actual in order to make the flow of the liquid easy to understand.

  As shown in FIG. 1, the valve body member 5 is pressed against the valve seat member 6 by the urging force of the return spring RS in a normal state (a state in which no current is supplied to the coil unit 4). The flow path R is in a closed state. When a current is supplied to the coil unit 4, the valve body member 5 is attracted to the fixed core 3 side against the urging force of the return spring RS by the fixed core 3 excited by the coil unit 4. 52 is separated from the valve seat member 6. Thereby, the flow path R of the base body B is opened.

  Further, when returning the normally closed electromagnetic valve 1 from the open state to the closed state, the supply of the current to the coil unit 4 is stopped so that the valve body member 5 is urged toward the valve seat member 6 by the urging force of the return spring RS. Move well. And if the liquid between the valve body member 5 and the valve seat member 6 is pressed by the valve body member 5 which moves in this way, a part of the liquid will be 1st flow path R1 and 2nd flow path R2. And it moves to the upper side of the valve body member 5 through 3rd flow path R3.

  At this time, as shown in FIGS. 3A and 3B, the second flow path R2 gradually narrows as the valve body member 5 moves, and the cross-sectional area of the flow path is cut off from the communication groove 51c. By making it smaller than the area, the narrowed portion functions as if it were an orifice, and the liquid cannot smoothly escape to the third flow path R3. Therefore, the liquid temporarily stays between the valve body member 5 and the valve seat member 6, functions as a damper, and the momentum of the valve body member 5 is weakened.

According to the above, the following effects can be obtained in the present embodiment.
Since the momentum of the valve body member 5 that moves vigorously by the return spring RS is weakened by the damper effect by the second flow path R2 that gradually narrows, a sudden collision between the valve body member 5 and the valve seat member 6 is suppressed. The occurrence of abnormal noise can be suppressed.

[Second Embodiment]
Next, a second embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In addition, since this embodiment changes a part of structure of the normally closed solenoid valve 1 which concerns on above-mentioned 1st Embodiment, about the component similar to 1st Embodiment, it is the same code | symbol The description will be omitted. In the drawings to be referred to, FIG. 4 is a longitudinal sectional view showing a normally closed solenoid valve according to a second embodiment.

  As shown in FIG. 4, the normally closed electromagnetic valve 1 ′ includes a fixed core 3 ′ and a movable core 51 ′ that are slightly different in structure from the first embodiment, and a valve seat member 6 according to the first embodiment. The flow sheet 7 and the sheet member 8 provided instead are mainly provided.

  The fixed core 3 ′ and the movable core 51 ′ are formed with relief portions 3 f and 51 f for making the stroke amount of the movable core 51 ′ larger than that in the embodiment. Other structures are the same as those in the above embodiment. A cylindrical suspension member 9 is fitted to the small diameter portion 51b of the movable core 51 '. The suspension member 9 has a plurality of through holes 91 formed at appropriate positions on the peripheral wall, and a claw portion 92 that is bent inward at the lower end portion.

  The flow sheet 7 is a substantially bottomed cylindrical member, and is arranged so that its opening faces downward. The bottom wall 71 of the flow sheet 7 has a tapered first valve seat surface 72 with which the valve body 52 abuts, and a through hole 73 that penetrates from the first valve seat surface 72 into the flow sheet 7. Is formed. In addition, a spherical contact surface 74 that contacts the sheet member 8 is formed on the lower outer periphery of the flow sheet 7, and a flange 75 protruding radially outward is formed on the upper outer periphery. Has been. Then, when the claw portion 92 of the suspension member 9 is hooked on the flange portion 75, the flow sheet 7 moves upward together with the movable core 51 '.

  The sheet member 8 is a cylindrical member, and is fixed to the lower portion of the body portion 22 by press-fitting. A tapered second valve seat surface 81 that contacts the contact surface 74 of the flow sheet 7 is formed on the upper opening edge of the seat member 8.

Next, the operation of the normally closed solenoid valve 1 ′ according to the second embodiment will be described.
As shown in FIG. 4, in normal times, the valve body member 5 ′ is pressed against the flow sheet 7 by the urging force of the return spring RS, and the flow sheet 7 is pressed against the sheet member 8. The path R is in a blocked state. When a current of a predetermined magnitude is supplied to the coil unit 4, the valve body member 5 ′ moves toward the fixed core 3 ′ excited by the coil unit 4 by a predetermined amount, and the valve body 52 is moved to the flow sheet 7. Separate from. As a result, the flow path R of the base B is slightly opened.

  Further, when a current larger than the predetermined size is supplied to the coil unit 4, the valve body member 5 ′ moves more than the amount of movement described above, so that the claw portion 92 of the suspension member 9 moves to the flow sheet 7. The flow sheet 7 is caught by the flange 75 and moves together with the valve body member 5 ′. As a result, the flow sheet 7 is separated from the sheet member 8 and the flow path R of the base B is largely opened.

  When the normally closed electromagnetic valve 1 ′ is returned from the open state to the closed state, the supply of current to the coil unit 4 is stopped, so that the valve body member 5 ′ and the flow sheet 7 are seated by the urging force of the return spring RS. It moves vigorously toward the member 8 side. At this time, since the second flow path R2 gradually narrowing similar to the first embodiment is formed by the movable core 51 ′ and the body portion 22, the momentum of the valve body member 5 ′ and the flow sheet 7 is reduced by the damper. It will be weakened by the effect. As a result, the flow sheet 7 is slowly seated on the sheet member 8 and the valve body member 5 ′ is slowly seated on the flow sheet 7.

According to the above, the following effects can be obtained in the second embodiment.
Since the momentum of the valve body member 5 ′ and the flow sheet 7 is weakened by the damper effect by the second flow path R2, the sudden collision between the flow sheet 7 and the sheet member 8, the valve body member 5 ′ and the flow sheet 7 is suppressed, and the generation of abnormal noise can be suppressed.

The present invention is not limited to the above embodiments, and can be used in various forms as exemplified below.
In each of the above embodiments, the normally closed solenoid valves 1 and 1 ′ are employed as the solenoid valves. However, the present invention is not limited to this, and for example, a normally open solenoid valve may be employed. However, as in the above-described embodiments, the normally closed electromagnetic valve in which the valve body member is moved more vigorously toward the valve seat member by the return spring is more likely to generate a large noise. The effect is exhibited more effectively.

  In each of the above-described embodiments, the movable core 51 (51 ′) is formed in a stepped shape, and is gradually narrowed by the large diameter part 51a and the upper end part 22c of the body part 22 facing the large diameter part 51a. Although the two flow paths R2 are formed, the present invention is not limited to this. For example, as shown in FIG. 5A, the lower part is formed on a tapered surface 51g of a movable core 51 "having a truncated cone shape and an upper end part 22c 'of the body part 22' along the tapered surface 51g. A second flow path R2 ′ that gradually narrows may be formed with the tapered surface 22h.

  Further, as shown in FIG. 5B, a second flow path R2 ″ that gradually narrows may be formed by the movable core 53 without the communication groove and the body portion 24 having the communication groove 24c. Therefore, the movable core 53 according to this embodiment is different from the movable core 51 according to the first embodiment only in that the communication groove 51c is not provided, and other shapes are formed in the same manner. The portion 24 is formed to extend to the fixed core 3 side so as to function as the guide tube 21 according to the first embodiment, and slidably supports the movable core 53. Further, the body portion 24 A communication groove 24c that connects the front and rear spaces in the traveling direction of the movable core 53 is formed along the vertical direction at an appropriate position on the sliding surface with the movable core 53. Then, a corner 24h on the lower end side of the communication groove 24c. Is when the movable core 53 is located at the lowest point. It is formed to be positioned below the corner 53h of the large-diameter portion 53a of the moving core 53. Thereby, the corner 24h on the lower end side of the communication groove 24c and the corner of the large-diameter portion 53a of the movable core 53 are formed. The second flow path R2 ″ that gradually narrows is formed by the portion 53h. In addition, according to this structure, the second flow path R2 ″ that gradually narrows can be formed without providing the flow path forming portion (upper end portion 22c) facing the large-diameter portion 51a as in the first embodiment. Can do.

In each said embodiment, although the communicating part was used as the communicating groove 51c, this invention is not limited to this, For example, a through-hole etc. may be sufficient.
In each said embodiment, although the valve body member 5 was comprised by 2 components, the movable core 51 and the valve body 52, this invention is not limited to this, For example, a movable core and a valve body are shape | molded integrally, and 1 component is formed. You may comprise a valve body member.

It is a longitudinal cross-sectional view which shows the normally closed type solenoid valve which concerns on 1st Embodiment. It is a cross-sectional view which shows the structure of a movable core. They are a perspective view (a) which shows the flow of a liquid when it begins to close a normally closed solenoid valve from an open state, and a perspective view (b) which shows the flow of a liquid just before finishing a normally closed solenoid valve. It is a longitudinal cross-sectional view which shows the normally closed type solenoid valve which concerns on 2nd Embodiment. It is a figure which shows the modification of the flow path which becomes narrow gradually, and is sectional drawing (a) which shows the form which formed the flow path with the taper surface of a movable core, and the taper surface of a body part, and the angle | corner of the large diameter part of a movable core It is sectional drawing (b) which shows the form which formed the flow path with the corner | angular part of the upper end opening of a part and a body part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Normally closed solenoid valve 3 Fixed core 4 Coil unit 5 Valve body member 6 Valve seat member 22 Body part 22c Upper end part 42 Coil 51 Movable core 51a Large diameter part 51b Small diameter part 51c Communication groove 52 Valve body R2 2nd flow path RS Return spring

Claims (3)

A valve seat member;
A valve body member that advances and retreats in a freely contacting manner with the valve seat member;
A housing that slides in contact with the valve body member and guides the forward and backward movement of the valve body member;
A communicating portion that communicates a front space of the valve body member on the valve seat member side and a rear space on the opposite side of the front space of the valve body member,
When the valve body member moves toward the valve seat member, the flow path through which the fluid pushed out from between the valve body member and the valve seat member gradually narrows as the valve body member moves. The throttle valve is formed between the valve body member and the housing so as to have a flow passage cross-sectional area smaller than the flow passage cross-sectional area of the communication portion. The valve body member is formed in a stepped shape with a small diameter on the valve seat member side, and a groove as the communication portion is formed on the outer peripheral surface thereof.
Around the small diameter portion of the valve body member, a flow path forming portion is provided that faces the large diameter portion of the valve body member in the traveling direction of the valve body member,
The electromagnetic valve according to claim 1, wherein the flow path is configured by a large diameter portion of the valve body member and the flow path forming portion. An elastic member for urging the valve body member toward the valve seat member;
The electromagnetic valve according to claim 1, further comprising a fixed core and a coil that separate the valve body member from the valve seat member against an urging force of the elastic member.

Images