JP2019183960A - Solenoid valve and manufacturing method of solenoid valve - Google Patents

Abstract

To secure sealing performance between a valve and a valve sheet in a case where a rod inclines.SOLUTION: A plunger 4 has a hole 4a and moves linearly with electromagnetic attractive force. A valve 6 has a hemispherical recess 6a and opens and closes a valve seat 5a. A rod 7 has: one end that is a hemispherical first projection 7a and is inserted into the hole 4a of the plunger 4 having an inner diameter larger than the outer diameter of the first projection 7a; and the other end that is a semispherical second projection 7b and transmits the linear movement of the plunger 4 to the valve 6 in a state of being inserted into the recess 6a of the valve 6 having an inner diameter larger than the outer diameter of the second projection 7b.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a solenoid valve and a method for manufacturing the solenoid valve.

  In a conventional solenoid valve, a plunger, a rod, and a valve are integrated. For example, in the electromagnetic valve according to Patent Document 1, the plunger is press-fitted into one end of the rod, and the valve is attached to the other end of the rod by a retainer and a washer.

JP 2013-108607 A

  Since the conventional solenoid valve is configured as described above, when the rod is tilted, the valve is also tilted together, and there is a problem that the sealing performance between the valve and the valve seat is lowered.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to ensure sealing performance when the rod is tilted.

  An electromagnetic valve according to the present invention includes a core, a coil for generating an electromagnetic attractive force in the core, a plunger having a hole and linearly moving by the electromagnetic attractive force, a valve seat formed in a fluid passage, and a hemispherical shape A valve that opens and closes the valve seat, and one end is a hemispherical first convex portion that is inserted into the hole of the plunger having an inner diameter larger than the outer diameter of the first convex portion, and the other end is hemispherical A rod that transmits the linear motion of the plunger to the valve in a state of being inserted into the concave portion of the valve that is the second convex portion and has an inner diameter larger than the outer diameter of the second convex portion.

  According to this invention, since the plunger, the rod and the valve are separated, the sealing performance when the rod is tilted can be ensured.

3 is a cross-sectional view showing a configuration example of a solenoid valve according to Embodiment 1. FIG. It is the figure which expanded the peripheral part of the valve | bulb and valve seat in the solenoid valve concerning Embodiment 1, FIG. 2A shows the state at the time of coil energization, FIG. 2B shows the state at the time of coil energization. 3A is a plan view of the valve according to Embodiment 1, FIG. 3B is an AA cross-sectional view, and FIG. 3C is a BB cross-sectional view. 4A and 4B are sectional views showing dimension examples of the plunger, the rod, and the valve in the first embodiment. It is a figure which shows the structural example of the transpiration gas processing system using the solenoid valve which concerns on Embodiment 1. FIG.

Embodiment 1 FIG.
FIG. 1 is a cross-sectional view illustrating a configuration example of the electromagnetic valve 1 according to the first embodiment. The electromagnetic valve 1 shown in FIG. 1 is in a valve open state.
The core 2 is a fixed iron core, and a through hole 2a through which the rod 7 passes is formed in the axial direction. The coil 3 is installed outside the core 2, and forms a magnetic field when energized to generate an electromagnetic attractive force in the core 2. The plunger 4 is a movable iron core and is attracted to the core 2 by an electromagnetic attraction force and linearly moves in the axial direction.

  The housing 5 is made of resin or the like, and serves as a fluid passage through which the first port 5b and the second port 5c communicate. A valve seat 5a is formed in the middle of this passage. The valve 6 is a non-magnetic material such as resin and opens and closes the valve seat 5a. An elastic portion 6c such as rubber is provided on the surface of the valve 6 that contacts the valve seat 5a. The rod 7 is a non-magnetic material such as resin, and transmits the linear motion of the plunger 4 to the valve 6 by linear motion in the through hole 2 a of the core 2.

  The first spring 8 biases the plunger 4 toward the valve seat 5a. The second spring 9 biases the valve 6 in a direction away from the valve seat 5a. The first spring 8 and the second spring 9 hold the positions of the plunger 4, the rod 7, and the valve 6 when the coil 3 is not energized. Note that the load of the second spring 9 is larger than the load of the first spring 8.

  FIG. 2 is an enlarged view of the periphery of the valve 6 and the valve seat 5a in the electromagnetic valve 1 according to the first embodiment. 2A shows a state when the coil 3 is not energized, and FIG. 2B shows a state when the coil 3 is energized.

  As described above, the load of the second spring 9 is larger than the load of the first spring 8. Therefore, when the coil 3 is not energized, the second spring 9 biases the valve 6 in a direction away from the valve seat 5a. The second spring 9 urges the valve 6 until the other end opposite to the one end provided with the elastic portion 6c comes into contact with a solenoid portion 10 described later. At this time, the valve 6 pushes the rod 7 and the plunger 4 in a direction away from the valve seat 5a. As a result, the valve 6 is separated from the valve seat 5a, and the valve seat 5a is opened.

  On the other hand, when the coil 3 is energized, the plunger 4 is electromagnetically attracted to the core 2 and moves in the direction of the valve seat 5a. At this time, the plunger 4 pushes the rod 7 and the valve 6 toward the valve seat 5a. As a result, the valve 6 comes into contact with the valve seat 5a, and the valve seat 5a is closed.

  As described in Patent Document 1, the conventional solenoid valve has a plunger, a rod, and a valve that are integrated. Therefore, when the rod is tilted, the valve is also tilted together, and there is a problem that the sealing performance between the valve and the valve seat is lowered. Further, in order to suppress the tilt of the rod, it is necessary to increase the dimensional accuracy of each component, but there is a problem that the improvement of the dimensional accuracy leads to an increase in cost. Furthermore, a process such as press-fitting for integrating the plunger, the rod, and the valve is required, and there is a problem that the cost is increased.

  Therefore, in the first embodiment, the plunger 4, the rod 7, and the valve 6 are all separated so that the valve 6 does not tilt even if the rod 7 tilts. In the first embodiment, a structure in which the plunger 4, the rod 7, and the valve 6 are all separated is referred to as a “floating structure”. With the floating structure, the sealing performance between the valve 6 and the valve seat 5a can be secured, high dimensional accuracy can be eliminated, and the assembly process can be simplified. Hereinafter, a specific example of the floating structure will be described.

  3A is a plan view of the valve 6 in Embodiment 1, FIG. 3B is an AA cross-sectional view, and FIG. 3C is a BB cross-sectional view. A hemispherical recess 6 a is formed on the surface of the bulb 6 facing the rod 7. Around the concave portion 6 a of the bulb 6, three contact portions 6 b having a shape protruding in the direction of the rod 7 are formed. The contact part 6b is a part for restricting the inclination of the rod 7 by contacting the rod 7 when the electromagnetic valve 1 is assembled. In the illustrated example, three contact portions 6b are formed on the valve 6, but the number of contact portions 6b is not limited to three and may be three or more.

  4A and 4B are cross-sectional views showing example dimensions of the plunger 4, the rod 7, and the valve 6 in the first embodiment. A hemispherical first convex portion 7a is formed at one end of the rod 7 on the plunger 4 side. The plunger 4 is formed with a hole 4a into which the first convex portion 7a of the rod 7 is inserted. Since the inner diameter of the hole 4a is larger than the outer diameter of the first convex portion 7a, the plunger 4 and the rod 7 are not fixed, and the end surface around the first convex portion 7a of the rod 7 is around the hole 4a of the plunger 4. It only touches the end face. Therefore, only the first convex portion 7a of the rod 7 is inserted into the hole 4a of the plunger 4, and a process such as press-fitting for integrating the rod 7 and the plunger 4 is unnecessary.

  A hemispherical second convex portion 7b is formed at one end of the rod 7 on the bulb 6 side. Since the inner diameter of the concave portion 6a of the bulb 6 is larger than the outer diameter of the second convex portion 7b, or the radius of curvature of the concave portion 6a is larger than the radius of curvature of the second convex portion 7b, the valve 6 and the rod 7 are not fixed. The second convex portion 7b only contacts the concave portion 6a. Therefore, only the second convex portion 7b of the rod 7 is inserted into the concave portion 6a of the valve 6, and the step of integrating the rod 7 and the valve 6 is not necessary. Even if the rod 7 is tilted, the valve 6 is not tilted, and the sealing performance between the valve 6 and the valve seat 5a is ensured.

Here, the assembly process of the electromagnetic valve 1 will be described.
First, the core 2, the coil 3, the plunger 4, the first spring 8, the yoke, and the like are integrated with resin to constitute the solenoid unit 10. Subsequently, the jig holds the housing 5 with the first port 5b facing downward. The second spring 9 and the valve 6 are installed on the housing 5 held by the jig. Subsequently, the second convex portion 7 b of the rod 7 is inserted into the concave portion 6 a of the valve 6. The outer peripheral surface of the rod 7 inclined with respect to the axial direction contacts at least one of the three contact portions 6b of the valve 6, and the rod 7 not fixed to the valve 6 is gripped by the contact portion 6b. It becomes a state. Subsequently, the solenoid unit 10 is assembled on the upper side of the housing 5. At that time, the rod 7 passes through the through hole 2 a of the core 2, and the first convex portion 7 a of the rod 7 is inserted into the hole 4 a of the plunger 4.

  When the clearance between the outer peripheral surface of the rod 7 and the contact portion 6b of the valve 6 is large, the inclination angle with respect to the axial direction of the rod 7 increases, and the first convex portion 7a is connected to the through hole 2a of the core 2 and the plunger 4. It is difficult to insert into the hole 4a. On the other hand, if the clearance is small, the contact portion 6b can reliably hold the rod 7 and the assemblability is improved. However, when the clearance is too small, there is a concern that a stick phenomenon may occur where the rod 7 is fitted into the contact portion 6b and cannot move during thermal expansion of the rod 7 or heat contraction of the contact portion 6b of the valve 6. Therefore, in order to improve the assemblability of the rod 7 and the plunger 4 while realizing the floating structure, the clearance needs to be within a predetermined range.

  As shown in FIGS. 4A and 4B, the outer diameter of the rod 7 is φD1, the inner diameter of the contact portion 6b is φD2, the thermal expansion coefficients of the rod 7 and the valve 6 are K1 and K2, respectively, the normal temperature is T0, The maximum temperature is Tmax and the minimum temperature is Tmin. The inner diameter of the hole 4a of the plunger 4 is φD3, the length of the rod 7 in the axial direction is L, and the angle at which the rod 7 is inclined with respect to the axial direction is θ. The clearance is preferably a value that satisfies the expressions (1) and (2). Equation (1) defines the minimum value of the clearance, and Equation (2) defines the maximum value of the clearance. According to the equations (1) and (2), the clearance is not less than a size that does not cause sticking even if the rod 7 is thermally expanded or the valve 6 is thermally contracted, and the rod 7 is inclined with respect to the axial direction. Even if it does, it is below the magnitude | size into which the 1st convex part 7a enters into the hole 4a of the plunger 4. FIG. Here, assuming that the rod 7 is inserted into the hole 4 a of the plunger 4, the inner diameter of the hole 4 a of the plunger 4 is set to φD 3. However, the rod 7 enters the through hole 2 a of the core 2 before the plunger 4. When inserted, the inner diameter of the through hole 2a of the core 2 is set to φD3.

φD2 × K2 × | T0−Tmin | −φD1 × K1 × | Tmax−T0 | ≧ 0 (1)

L × sin θ <φD3 (2)

  Finally, a vaporized gas treatment system for a vehicle will be described as an example of the use of the solenoid valve 1 according to the first embodiment. FIG. 5 is a diagram illustrating a configuration example of a transpiration gas processing system using the solenoid valve 1 according to the first embodiment. The electromagnetic valve 1 according to Embodiment 1 is used for at least one of the purge valve 104 or the canister vent valve 106.

  The fuel tank 100 and the canister 102 are connected by a transpiration gas passage 101, and the canister 102 and the engine intake manifold are connected by a purge passage 103. The purge passage 103 is provided with a purge valve 104 that opens and closes the purge passage 103. An atmospheric release passage 105 is connected to the canister 102. A canister vent valve 106 that opens and closes the atmosphere release passage 105 is installed in the atmosphere release passage 105.

  The vaporized gas evaporated in the fuel tank 100 flows through the vaporized gas passage 101 and enters the canister 102, the fuel component is adsorbed by the canister 102, and the gas component is discharged from the atmosphere opening passage 105 to the outside of the vehicle. The fuel component adsorbed by the canister 102 is sucked by the intake system negative pressure of the engine, flows through the purge passage 103, enters the intake manifold, and is burned by the engine.

  When diagnosing leaks in the piping system such as the transpiration gas passage 101 and the purge passage 103 in this transpiration gas processing system, the purge valve 104 and the canister vent valve 106 are closed, and pressure fluctuations in the piping are monitored.

  As described above, the electromagnetic valve 1 according to the first embodiment includes the core 2, the coil 3, the plunger 4, the valve seat 5a, the valve 6, and the rod 7. The coil 3 generates an electromagnetic attractive force in the core 2. The plunger 4 has a hole 4a and moves linearly by an electromagnetic attractive force. The valve seat 5 a is formed in the fluid passage of the housing 5. The valve 6 has a hemispherical recess 6a and opens and closes the valve seat 5a. One end of the rod 7 is a hemispherical first convex portion 7a and is inserted into the hole 4a of the plunger 4 having an inner diameter larger than the outer diameter of the first convex portion 7a, and the other end is a hemispherical second convex portion 7b. In this state, the linear motion of the plunger 4 is transmitted to the valve 6 while being inserted into the concave portion 6a of the valve 6 having an inner diameter larger than the outer diameter of the second convex portion 7b. The solenoid valve 1 is provided with a floating structure in which the plunger 4, the rod 7 and the valve 6 are separated to ensure the sealing performance between the valve 6 and the valve seat 5a even when the rod 7 is inclined with respect to the axial direction. Can do.

  Further, the valve 6 of the first embodiment has a shape protruding around the recess 6a and has three or more contact portions 6b that contact when the rod 7 is inclined with respect to the axial direction. Thereby, the three or more contact parts 6b can hold | grip the rod 7 reliably, and the assembly property of the solenoid valve 1 improves.

  In the first embodiment, the clearance between the outer peripheral surface of the rod 7 and the contact portion 6b is not less than a size that does not cause a stick phenomenon even if the rod 7 is thermally expanded or the valve 6 is thermally contracted, and Even if the rod 7 is inclined with respect to the axial direction, the first convex portion 7 a is not larger than the size of the hole 4 a of the plunger 4. Thereby, the assembly property of the rod 7 and the plunger 4 can be improved while realizing a floating structure.

  Further, in the method for manufacturing the solenoid valve 1 according to the first embodiment, the step in which the second convex portion 7b of the rod 7 is inserted into the concave portion 6a from above the valve 6 and the outer peripheral surface of the rod 7 is in contact with the valve 6 A step in which the first convex portion 7a of the rod 7 is inserted into the hole 4a of the plunger 4 while being in contact with the portion 6b. Thereby, the process of press-fitting etc. like the conventional one becomes unnecessary, and the assembly process of the solenoid valve 1 can be simplified.

  In the present invention, any component of the embodiment can be modified or any component of the embodiment can be omitted within the scope of the invention.

  1 solenoid valve, 2 core, 2a through hole, 3 coil, 4 plunger, 5 housing, 5a valve seat, 5b first port, 5c second port, 6 valve, 6a recess, 6b abutting part, 6c elastic part, 7 Rod, 7a First convex portion, 7b Second convex portion, 8 First spring, 9 Second spring, 10 Solenoid portion, 100 Fuel tank, 101 Transpiration gas passage, 102 Canister, 103 Purge passage, 104 Purge valve, 105 Open to atmosphere Aisle, 106 canister vent valve.

Claims (5)

The core,
A coil for generating an electromagnetic attractive force in the core;
A plunger having a hole and linearly moving by the electromagnetic attractive force;
A valve seat formed in the fluid passageway;
A valve having a hemispherical recess and opening and closing the valve seat;
One end is a hemispherical first convex portion and is inserted into the hole of the plunger having an inner diameter larger than the outer diameter of the first convex portion, and the other end is a hemispherical second convex portion and the second convex portion A solenoid valve comprising: a rod that transmits a linear motion of the plunger to the valve in a state of being inserted into the concave portion of the valve having an inner diameter larger than an outer diameter of the portion.   The electromagnetic valve according to claim 1, wherein the valve has a shape protruding around the recess and has three or more contact portions that contact when the rod is inclined with respect to the axial direction.   The clearance between the outer peripheral surface of the rod and the contact portion is not less than a size that does not cause sticking even if the rod is thermally expanded or the valve is thermally contracted, and the rod is in the axial direction. 3. The solenoid valve according to claim 2, wherein the first convex portion is not larger than the size of the plunger into the hole even if it is inclined.   The electromagnetic valve according to any one of claims 1 to 3, wherein the atmosphere opening passage of the canister is opened and closed. The core,
A coil for generating an electromagnetic attractive force in the core;
A plunger having a hole and linearly moving by the electromagnetic attractive force;
A valve seat formed in the fluid passageway;
A valve having a hemispherical recess and opening and closing the valve seat;
One end is a hemispherical first convex portion and is inserted into the hole of the plunger having an inner diameter larger than the outer diameter of the first convex portion, and the other end is a hemispherical second convex portion and the second convex portion A rod that transmits linear motion of the plunger to the valve in a state of being inserted into the concave portion of the valve having an inner diameter larger than the outer diameter of the portion;
The valve is a method of manufacturing an electromagnetic valve having three or more abutting portions that come into contact with the rod when the rod is inclined with respect to the axial direction in a shape protruding around the recess,
The second convex part of the rod is inserted into the concave part from above the valve;
And a step of inserting the first convex portion of the rod into the hole of the plunger in a state where the outer peripheral surface of the rod is in contact with the contact portion of the valve. Method.

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