JP4741778B2 - Solenoid and solenoid valve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a solenoid and a solenoid valve including the solenoid.
[0002]
[Prior art]
The solenoid is suitably used for a solenoid valve that performs various fluid control and the like. With reference to FIG. 4, the solenoid valve provided with the solenoid which concerns on a prior art is demonstrated. FIG. 4 is a schematic cross-sectional view of a conventional solenoid valve.
[0003]
The solenoid valve 100 includes a solenoid part 100A and a valve part 100B.
[0004]
Here, in the illustrated example, the valve portion 100B is a spool valve type that can control the inflow amount and the outflow amount of the fluid by changing the opening area of the valve according to the stroke of the spool.
[0005]
The solenoid unit 100A is roughly composed of a substantially cylindrical coil 103 that generates a magnetic field when energized, a plunger 101 that is magnetically attracted to the center post 102 by the magnetic field generated by the coil 103, and a valve unit 100B that drives the plunger 101. A rod 105 connected to the plunger 101 for transmission to (specifically, a spool), and an abbreviated provision for covering the outer peripheral surfaces of the plunger 101 and the center post 102 for positioning (centering). A bottomed cylindrical sleeve 104.
[0006]
Next, the operation of the solenoid valve 100 will be described.
[0007]
The plunger 101 is positioned in a direction away from the center post 102 in a normal state, that is, in a state where the coil 103 is not energized.
[0008]
In general, the plunger 101 is biased in a direction away from the center post 102 by a biasing member such as a spring. In the illustrated example, the plunger 101 is configured to be separated from the center post 102 via the spool by providing a spring that biases the spool toward the solenoid portion 100A.
[0009]
When the coil 103 is energized, the coil 103 generates a magnetic field to form a magnetic path, and the plunger 101 is magnetically attracted to the center post 102.
[0010]
Therefore, the magnetic force can be controlled by the magnitude of the current flowing through the coil 103, and the stroke amount of the spool can be controlled by controlling the movement amount of the plunger 101, thereby controlling the flow rate of the fluid. In addition, various fluid pressure controls such as hydraulic control can be performed.
[0011]
Here, in the solenoid or the solenoid valve provided with the solenoid, it is desirable that the magnetic attraction force by the center post with respect to the plunger is large from the viewpoint of miniaturization of the apparatus and power consumption. In addition, from the viewpoint of quality, it is desirable that the plunger reciprocates smoothly, and that the plunger has as little misalignment as possible (the center axis reciprocates as little as possible).
[0012]
From this point, in order to increase the magnetic attraction force, in the case of the solenoid valve 100 shown in FIG. 4, the center post 102 is not only the first attraction surface 102a facing the front end surface 101a of the plunger 101. The second suction surface 102b facing the outer peripheral side surface 101b of the plunger 101 is also provided.
[0013]
In addition, in the case of the solenoid valve 100 shown in FIG. 4, the plunger 101 and the center post 102 are not attracted (residual magnetic adsorption) in order to make the plunger smoothly reciprocate and minimize the misalignment of the plunger. As shown, a shim 106 made of a non-magnetic member is provided between the distal end surface 101a of the plunger 101 and the first suction surface 102a of the center post 102, the plunger 101 is supported by the sleeve 104, and the plunger 101 The coaxiality is increased by supporting the rod 105 fixed to the shaft by the bearing 107.
[0014]
Here, in order to increase the magnetic attraction force described above, it is necessary to reduce the distance (air gap) between the outer peripheral side surface of the plunger 101 and the inner peripheral side surface of the center post 102 as much as possible.
[0015]
However, if this distance is too small, the outer peripheral side surface of the plunger 101 and the inner peripheral side surface of the center post 102 may come into contact with each other. The lateral suction force by the second suction surface 102b of the center post 102 is increased, the sliding resistance is increased, and the hysteresis is increased, so that the plunger 101 does not move smoothly. Also, if the tilt of the rod is large, the sliding resistance with the bearing is increased, which causes a higher hysteresis.
[0016]
In order to minimize the distance between the outer peripheral side surface of the plunger 101 and the inner peripheral side surface of the center post 102 while avoiding such an increase in sliding resistance, it is necessary to increase the above-described coaxiality. .
[0017]
However, as described above, the prior art shown in FIG. 4 has a configuration in which the plunger 101 is supported by the sleeve 104 and the rod 105 fixed to the plunger 101 is supported by the bearing 107 to increase the coaxiality.
[0018]
Therefore, since the coaxiality is determined by the two members, the arrangement relationship between the two members also affects the coaxiality. Therefore, not only the size and shape accuracy of the two members and the plunger and the rod, but also the size and shape of the member interposed between the two members have an influence on the coaxiality.
[0019]
Thus, in the configuration of the prior art, since a plurality of members are involved in increasing the coaxiality, the accuracy of the dimensions and shapes of the plurality of members is increased, and the coaxiality is set to a certain level of accuracy. It was very difficult to do.
[0020]
[Problems to be solved by the invention]
As described above, in the case of the prior art, it is difficult to improve the coaxiality. In addition, since it is difficult to improve the coaxiality, it is difficult to increase the suction force of the plunger by the center post.
[0021]
An object of the present invention is to provide a solenoid that improves the suction force of the plunger by the center post and improves the coaxiality.
[0022]
[Means for Solving the Problems]
The present invention is applied to a solenoid including a center post having a first suction surface facing the tip end surface of the plunger and a second suction surface facing the outer peripheral side surface of the plunger.
[0023]
That is, the solenoid generally includes a plunger and a center post, and by exciting excitation means such as a coil, a magnetic circuit passing through the plunger and the center post is formed, and the plunger is magnetically connected to the center post. It has a function of driving the plunger by utilizing suction. Therefore, it is necessary to provide a suction surface for suitably sucking the plunger on the center post.
[0024]
In the solenoid of the present invention, the center post is provided with the first suction surface and the second suction surface as described above as such a suction surface.
[0025]
And in order to achieve the said objective, in this invention, the nonmagnetic member interposed between the outer peripheral side surface of a plunger and the 2nd suction surface of a center post is provided, It is characterized by the above-mentioned.
[0026]
By providing the nonmagnetic member in this way, it is possible to prevent the plunger and the center post from directly hitting even if the plunger is inclined. Therefore, it is possible to prevent the lateral magnetic attractive force with respect to the plunger from being concentrated on a part and becoming larger than necessary, and it is possible to prevent the hysteresis from becoming large.
[0027]
Therefore, the clearance between the outer peripheral side surface of the plunger and the facing surface facing the outer peripheral side surface of the center post is sufficiently small without being affected by the coaxiality of the plunger or the like as long as the nonmagnetic member is provided. It becomes possible.
[0028]
As a result, if the thickness of the member to be magnetized is reduced, the gap between the outer peripheral side surface of the plunger and the opposing surface facing the outer peripheral side surface of the center post is reduced, and the plunger is attracted by the center post. You can improve your power.
[0029]
And if the nonmagnetic member mentioned above has the support function which supports the outer peripheral side surface of a plunger so that sliding is possible, the center deviation of a plunger can be prevented with a nonmagnetic member.
[0030]
In addition, the nonmagnetic member can be easily assembled to the center post by being fitted and fixed to the center post. If the non-magnetic member is configured to be fitted and fixed to the center post and has a support function for slidably supporting the outer peripheral side surface of the plunger, the plunger is interposed via the non-magnetic member. It will be positioned with respect to a center post, and the coaxiality of a plunger and a center post will increase.
[0031]
Further, if the non-magnetic member integrally has a magnetic adsorption preventing portion interposed between the tip end surface of the plunger and the first suction surface of the center post, magnetic adsorption between the plunger and the center post can be prevented. .
[0032]
Moreover, the non-magnetic member integrally includes a guide that slidably supports the outer peripheral surface of the rod fixed to the plunger, thereby preventing the rod from being misaligned.
[0033]
In particular, the non-magnetic member has such a rod guide integrally and has a support function for slidably supporting the outer peripheral side surface of the plunger so that the rod is fixed to the plunger and the plunger. Since both are guided by a single non-magnetic member, the coaxiality can be made extremely high.
[0034]
If the non-magnetic member is fitted and fixed to the center post in such a configuration, the plunger and the rod are positioned with respect to the center post via the non-magnetic member. In addition, the coaxiality between the rod and the center post is extremely increased.
[0035]
DETAILED DESCRIPTION OF THE INVENTION
Exemplary embodiments of the present invention will be described in detail below with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. Absent.
[0036]
Reference Example 1 A solenoid according to Reference Example 1 of the present invention will be described with reference to FIG. In this reference example , a case where a solenoid is applied to a solenoid valve will be described as an example.
[0037]
FIG. 1 is a schematic cross-sectional view of a solenoid valve according to Reference Example 1 of the present invention.
[0038]
The solenoid valve 1 includes a solenoid part 1A and a valve part 1B.
[0039]
Here, the valve portion 1B shows a case of a spool valve in the illustrated example, and a spool 11 is provided inside the valve sleeve 10 so as to be capable of reciprocating, and the valve sleeve 10 according to the stroke of the spool 11 is provided. Since the opening area of the formed valve changes, the amount of fluid inflow and outflow can be controlled by controlling the stroke amount of the spool 11 with a solenoid.
[0040]
The solenoid portion 1A is roughly configured such that a magnetic circuit is formed by a coil 4 as a substantially cylindrical excitation means that generates a magnetic field by energization, and a magnetic field generated by energization of the coil 4, so that the center post 3 is magnetically formed. A plunger 2 to be sucked, a substantially bottomed cylindrical metal sleeve 5 serving as a bearing for the plunger 2, and a rod 6 connected and fixed to the plunger 2 in order to transmit the drive of the plunger 2 to the spool 11. I have.
[0041]
The center post 3 has a first suction surface 31 that faces the distal end surface 21 of the plunger 2 and a second suction surface 32 that faces the outer peripheral side surface 22 of the plunger 2.
[0042]
In addition, a bracket plate 9 having a substantially flat portion extending radially to form a magnetic path and having a bracket for fixing the solenoid valve body at a predetermined position, a coil 4, a center post 3, a plunger 2, and a sleeve 5 and a case member 14 containing various components including the bracket plate 9.
[0043]
Furthermore, an upper plate 8 that forms a magnetic path, a spring 15 that urges the plunger 2 in a direction away from the center post 3 through the rod 6 together with the spool 11, and a terminal for energizing the coil 4 are provided. A seal member 12 that prevents leakage of fluid from the inside of the connector 13 and the valve portion 1B to the coil 4 side, and prevents water (foreign matter) from entering the coil causing poor insulation of the coil or causing short-circuiting. I have.
[0044]
Next, the operation of the solenoid valve 1 will be described.
[0045]
In the normal state, that is, when the coil 4 is not energized, the plunger 2 is positioned in a direction away from the center post 3. In other words, in this reference example , the spool 11 is connected to the spring as described above. The plunger 2 is separated from the center post 3 by being urged by 15 in the direction of the solenoid portion 1A.
[0046]
By energizing the coil 4, a magnetic path (magnetic path formed by the case member 14, the upper plate 8, the plunger 2, the center post 3, and the bracket plate 9) is formed, and the plunger 2 is magnetically applied to the center post 3. Is aspirated.
[0047]
Therefore, the magnetic force can be controlled by the magnitude of the current flowing through the coil 4, and the stroke amount of the spool 11 can be controlled by controlling the movement amount of the plunger 2, thereby controlling the flow rate of the fluid. In addition, various fluid pressure controls such as hydraulic control can be performed.
[0048]
In this reference example , a guide 7 made of a non-magnetic material is fitted and fixed to the center post 3. Next, the guide 7 will be described in detail.
[0049]
The guide 7 includes a plunger guide portion 71 interposed between the outer peripheral side surface 22 of the plunger 2 and the second suction surface 32 of the center post 3, and the tip surface 21 of the plunger 2 and the first suction surface 31 of the center post 3. A magnetic adsorption preventing part 72 interposed therebetween and a fitting part 73 fitted to the inner periphery of the through hole 33 for allowing the rod 6 in the center post 3 to pass therethrough are provided.
[0050]
The guide 7 can be easily assembled simply by fitting the fitting portion 73 provided in the guide 7 to the inner periphery of the through hole 33 of the center post 3.
[0051]
The plunger guide portion 71 mainly has a function of preventing the outer peripheral side surface 22 of the plunger 2 from contacting the second suction surface 32 of the center post 3 and a function of supporting the outer peripheral side surface 22 of the plunger 2 so as to be slidable. Prepare.
[0052]
The contact between the outer peripheral side surface 22 of the plunger 2 and the second attraction surface 32 of the center post 3 is prevented, so that the magnetic attraction force does not concentrate in one place.
[0053]
In particular, the plunger guide portion 71 slidably supports the outer peripheral side surface 22 of the plunger 2, so that the distance between the outer peripheral side surface 22 of the plunger 2 and the second suction surface 32 of the center post 3 is substantially equal on the entire circumference. can do.
[0054]
More specifically, for example, as shown in the figure, the plunger guide portion 71 is accommodated in the annular gap between the plunger 2 and the center post 3, and the inner peripheral surface of the plunger guide portion 71 can slide on the outer peripheral surface of the plunger 2. The outer peripheral surface 22 of the plunger 2 and the second suction surface of the center post 3 are made so that the outer peripheral surface of the plunger guide portion 71 contacts the inner peripheral surface (second suction surface 32) of the center post 3. The distance between the two is approximately equal to the thickness of the plunger guide portion 71.
[0055]
Therefore, the distance between the outer peripheral side surface 22 of the plunger 2 and the second suction surface 32 of the center post 3 can be made substantially equal over the entire circumference.
[0056]
As a result, since this interval can be made uniform, the magnetic attraction force directed in the axial direction can be made uniform over the entire circumference, and the occurrence of biased lateral force can be prevented, thereby preventing an increase in hysteresis. be able to.
[0057]
As described above, since the interval between the outer peripheral side surface 22 of the plunger 2 and the second suction surface 32 of the center post 3 can be made uniform, the coaxiality of the plunger 2 or the like is not greatly affected, and as a result, this The interval can be reduced compared to the conventional case.
[0058]
That is, conventionally, since the space between the outer peripheral side surface of the plunger and the second suction surface of the center post has been a space (air gap), in order to prevent these from coming into contact, a sufficient air gap must be taken. Therefore, it has been an obstacle to increase the magnetic attractive force.
[0059]
On the other hand, in the case of the present reference example , the plunger guide portion 71 can prevent contact between the outer peripheral side surface 22 of the plunger 2 and the second suction surface 32 of the center post 3. Accordingly, the distance between the outer peripheral side surface 22 of the plunger 2 and the second attraction surface 32 of the center post 3 can be reduced, and the magnetic attraction force can be improved. Accordingly, it is possible to reduce the size of the apparatus and reduce the power consumption.
[0060]
In addition, since the plunger guide part 71 is comprised from the nonmagnetic body, the adsorption | suction by a residual magnetic adsorption | suction does not become a problem.
[0061]
In addition, since the plunger guide portion 71 has a function of slidably supporting the outer peripheral side surface 22 of the plunger 2, the plunger 2 does not increase the sliding resistance when the plunger 2 moves, and Since the misalignment of the plunger 2 can be prevented, the reciprocating movement of the plunger 2 can be performed smoothly.
[0062]
Particularly, since the guide 7 including the plunger guide portion 71 is fitted to the center post 3 by the fitting portion 73, the coaxiality between the plunger 2 and the center post 3 has high accuracy. Therefore, the plunger 2 can perform a stable reciprocating movement.
[0063]
The guide 7 includes a magnetic adsorption preventing unit 72. That is, the shim function in the prior art is also provided integrally.
[0064]
Thereby, it can prevent that the front end surface 21 of the plunger 2 and the 1st attraction | suction surface 31 of the center post 3 adsorb | suck by a residual magnetic adsorption, and the smooth reciprocation of the plunger 2 is enabled.
[0065]
As described above, in the solenoid valve 1 according to this reference example , the magnetic attractive force of the plunger 2 by the center post 3 can be improved. Further, the coaxiality can be achieved, and the plunger 2 can be driven stably.
[0066]
Next, a preferred application example of the solenoid valve 1 according to this reference example will be described.
[0067]
In engines such as automobiles, the intake / exhaust valves of the engine are opened and closed by rotating the camshaft. However, the fuel efficiency is improved by controlling the valve timing appropriately according to the operating conditions (high speed and low speed). It becomes possible to obtain exhaust gas purification.
[0068]
This valve timing control can be performed by shifting the camshaft in the rotational direction and changing the phase, and a technique of performing this by a solenoid valve is known as a known technique.
[0069]
Here, in order to shift the camshaft in the rotational direction, hydraulic control by a solenoid valve is performed. However, due to the arrangement space and the like, a solenoid valve is installed on the path of the engine oil flow path, It is common to use it.
[0070]
Conventionally, by using a solenoid valve that performs on / off control, control has been performed in two types of states at high speed and low speed, but in recent years linear control has been performed in order to perform more precise control. Possible solenoid valves are used.
[0071]
Therefore, the solenoid valve according to this reference example described above can be suitably used as a linear control solenoid valve for such valve timing control (VTC).
[0072]
Reference Example 2 Reference Example 2 is shown in FIG. In the reference example 1 , the configuration in which the axis is supported by the plunger by the sleeve and the guide has been described. In this reference example , a configuration in which the shaft is supported by a plunger by a guide and a rod fixed to the plunger by a dedicated bearing will be described.
[0073]
Since the same as in Reference Example 1 for other configurations and operations, a description thereof will be omitted.
[0074]
FIG. 2 is a schematic cross-sectional view of a solenoid valve according to Reference Example 2 of the present invention.
[0075]
In the case of the solenoid valve 1a according to this reference example , a gap is provided between the inner peripheral side surface of the sleeve 5a and the outer peripheral side surface of the plunger 2, and the sleeve 5a does not function as a bearing for the plunger 2. .
[0076]
Also in this reference example , a guide 7 is provided, and this guide 7 has the same configuration and the same function as the case of the reference example 1 described above. Therefore, the outer peripheral side surface 22 of the plunger 2 is slidably supported by the plunger guide portion 71 of the guide 7.
[0077]
In this reference example , the bearing 16 of the rod 6 is provided on the inner periphery of the through hole 33 provided in the center post 3. The bearing 16 is provided with a slit 16a, which allows fluid to flow back and forth to maintain the responsiveness of the plunger 2.
[0078]
As described above, in this reference example , the plunger 2 is supported by the guide 7 and the rod 6 fixed to the plunger 2 is supported by the bearing 16 so that the shaft is aligned (the coaxiality is obtained).
[0079]
Other configurations and the like are the same as those in the first reference example .
[0080]
(The implementation of Embodiment) FIG 3 is an embodiment of the present invention is shown. In the present embodiment, a configuration in which the guide supports not only the plunger but also the rod will be described.
[0081]
Since the same as in Reference Example 1 for other configurations and operations, a description thereof will be omitted.
[0082]
Figure 3 is a schematic cross-sectional view of a solenoid valve according to the implementation of the embodiment of the present invention.
[0083]
In the case of the solenoid valve 1b according to the present embodiment, a gap is provided between the inner peripheral side surface of the sleeve 5a and the outer peripheral side surface of the plunger 2, and the sleeve 5a functions as a bearing for the plunger 2. Absent. However, the sleeve that functions as the bearing of the plunger 2 as described in the first reference example may be used.
[0084]
As in the case of the reference example 1 , the guide 7a in the present embodiment includes a plunger guide portion 71a interposed between the outer peripheral side surface 22 of the plunger 2 and the second suction surface 32 of the center post 3, and the plunger 2 A magnetic adsorption preventing portion 72a interposed between the front end surface 21 and the first attraction surface 31 of the center post 3 and a fitting fitted to the inner periphery of the through hole 33 for allowing the rod 6 in the center post 3 to pass therethrough. Part 73a.
[0085]
And the guide 7a in this Embodiment is further provided with the rod guide 74a which supports the outer peripheral surface 61 of the rod 6 fixed to the plunger 2 so that sliding is possible.
[0086]
Thus, in this Embodiment, it comprised so that the plunger 2 and the rod 6 fixed to the plunger 2 might be supported by one member, ie, the guide 7a.
[0087]
As a result, misalignment (axial misalignment) between the plunger 2 and the rod 6 can be prevented with extremely high accuracy.
[0088]
In particular, in this embodiment, since the guide 7a is fitted to the center post 3, the coaxiality of the plunger 2 and the rod 6 with respect to the center post 3 can be maintained with high accuracy. Therefore, the reciprocating movement of the plunger 2 and the rod 6 can be performed smoothly.
[0089]
【The invention's effect】
As described above, the present invention can improve the suction force of the plunger by the center post. Further, the coaxiality can be improved.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view of a solenoid valve according to Reference Example 1 of the present invention.
FIG. 2 is a schematic cross-sectional view of a solenoid valve according to Reference Example 2 of the present invention.
Figure 3 is a schematic cross-sectional view of a solenoid valve according to the implementation of the embodiment of the present invention.
FIG. 4 is a schematic cross-sectional view of a solenoid valve according to the prior art.
[Explanation of symbols]
1, 1a, 1b Solenoid valve 1A Solenoid part 1B Valve part 2 Plunger 21 Tip surface 22 Outer peripheral surface 3 Center post 31 First suction surface 32 Second suction surface 33 Through hole 4 Coil 5, 5a Sleeve 6 Rod 61 Outer peripheral surface 7, 7a Guide 8 Upper plate 9 Bracket plate 10 Valve sleeve 11 Spool 12 Seal member 13 Connector 14 Case member 15 Spring 16 Bearing 16a Slit 71, 71a Plunger guide portion 72, 72a Magnetic adsorption preventing portion 73, 73a Fitting portion 74a Rod guide

Claims (2)

A plunger that reciprocates in response to energization and de-energization of the excitation means;
A rod fixed to the plunger;
A first suction surface opposed to the distal end surface of the plunger; a second suction surface opposed to the outer peripheral side surface of the plunger; and a through hole for allowing the rod to penetrate on the inner peripheral side; A center post that magnetically attracts the plunger by excitation of
A solenoid comprising a non-magnetic member interposed between the outer peripheral side surface of the plunger and the second suction surface of the inner periphery of the center post , and between the outer peripheral side surface of the rod and the inner periphery of the through hole ,
The non-magnetic member is
A plunger guide part interposed between the outer peripheral side surface of the plunger and the second suction surface of the center post, and slidably supporting the outer peripheral side surface of the plunger;
A magnetic adsorption preventing part interposed between the front end surface of the plunger and the first attraction surface of the center post;
A fitting portion fitted to the inner periphery of the through hole of the center post;
A rod guide that slidably supports the outer peripheral surface of the rod;
A solenoid characterized by being provided integrally . A solenoid valve comprising the solenoid according to claim 1 and a valve that opens and closes by movement of the plunger.

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