JPH07167324A - Solenoid valve - Google Patents

Abstract

PURPOSE:To provide a solenoid valve which is prepared by holding a bearing while caulking a bearing holding member, and fitting the bearing holding member to an installation port of a housing. CONSTITUTION:A solenoid valve 1 is prepared by mounting a bearing holding member 3 to a housing 2, and further mounting a solenoid 4 to an upper surface of the bearing holding member 3. The bearing holding member 3 is integrally molded by aluminum die-casting. A third stepped portion 17c of a center port 17 is pressed from an upper side by a caulking jig. A large diameter portion 24 and a small diameter portion 25 to which an installation port of the housing 2 is fitted are formed on an outer periphery of the bearing holding member 3. A gap S exists between the small diameter portion 25 of the bearing holding member 3 and the installation port of the housing 2, so that an expansion part, being formed on the outer periphery of the small diameter portion 25 by caulking, is prevented from being abutted against an inner wall of the installation port.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid valve, and more particularly to a solenoid valve configured to crimp a bearing holding member that fits into a mounting hole of a housing to hold the bearing.

[0002]

2. Description of the Related Art Generally, an electromagnetic valve is used in which a valve body is opened and closed by an electromagnetic force of a solenoid. Some solenoid valves of this type have a structure in which a bearing that supports a valve shaft of a valve element is held by a bearing holding member by caulking.

In an automobile engine, for example, in order to reduce nitrogen oxides (NOx) contained in the exhaust gas, a part of the exhaust gas is taken out from the exhaust system passage, and the temperature, timing and flow rate of the taken out exhaust gas. Exhaust Gas Recirculation System (Exhaust Gas Recirculation System)
circultion System) has been adopted.

In this exhaust gas recirculation system, an electromagnetic valve having a bearing holding member as described above recirculates a part of the exhaust gas to the intake system passage (hereinafter referred to as "EGR valve"). ) Is used as. Therefore, the EGR valve opens by separating the valve element provided at the end of the valve shaft driven by the solenoid from the valve seat, and the valve shaft is made of carbon (heat resistance is Through the bearing of FIG.

In such an EGR valve used in the exhaust gas recirculation system, since hot exhaust gas flows inside the solenoid valve, it is necessary to prevent heat of the exhaust gas from being conducted to the solenoid. Therefore, the EGR valve has a bearing holding member for holding the bearing interposed between the housing and the solenoid in which a passage through which exhaust gas flows is formed, and has a cooling water passage through which the bearing water flows. The bearing holding member is provided to cool the bearing holding member.

In order to prevent the exhaust gas from leaking, the bearing is caulked to lock the gasket and the washer, and is held by the bearing holding member via the washer.

A bearing holding member incorporated in a conventional EGR valve includes a cooling body made of an aluminum alloy to which a stainless pipe for supplying cooling water is fixed, and a holding portion made of free-cutting steel for holding the bearing. The holder is fixed to the mounting hole of the cooling body by caulking to be integrated.

[0008]

However, in the past, EG was used.
Since the bearing holding member of the R valve is composed of two members, there are problems that the number of parts is large and the entire cover needs to be cut so that the cover has a predetermined shape, and the manufacturing cost becomes considerably high. .

Therefore, it has been considered to integrally mold the cooling body and the holding portion by aluminum die casting. However, since the thickness of the surrounding wall portion where the inner periphery of the bearing holding member that locks the gasket and the washer is caulked is determined based on the strength of the free-cutting steel,
When integrally molded by aluminum die casting, which has lower rigidity than free-cutting steel, the portion to be caulked has insufficient strength.

Such insufficient strength of the bearing holding member can be solved by making the surrounding wall portion to be caulked sufficiently thick, but in this case, the fitting portion of the housing also has a large diameter. Therefore, the size of the entire solenoid valve is increased.

Therefore, if the solenoid valve is integrally molded by aluminum die-casting in the same shape as the conventional one so that the solenoid valve does not increase in size, the outer peripheral surface of the bearing holding member bulges outward at the insufficient strength portion during caulking. As a result, the bearing holding member cannot be inserted into the mounting portion of the valve body of the EGR valve.

In view of the above problems, therefore, the present invention is to integrally form a bearing holding member by aluminum die casting, and
The purpose is to prevent deformation due to caulking.

[0013]

The invention according to claim 1 is
A housing having a valve seat in the middle of a flow path of a fluid, a solenoid fixed to the housing, a valve shaft sliding axially by the solenoid, and an excitation of the solenoid provided at an end of the valve shaft, Electromagnetic including a valve body that opens and closes the valve seat by demagnetization, a bearing that slidably supports the valve shaft, and a bearing holding member that is fitted into a mounting hole of the housing and holds the bearing. In the valve, a step portion that forms a gap between the bearing holding member and the mounting hole of the housing is provided on the outer periphery of the bearing holding member.

The invention according to claim 2 is a housing having a valve seat in the middle of a flow path of a fluid, a solenoid fixed to the housing, a valve shaft axially slid by the solenoid, and the valve. A valve body provided at the end of the shaft for opening and closing the valve seat by exciting and demagnetizing the solenoid, a bearing for slidably supporting the valve shaft, and a fitting hole formed in the mounting hole of the housing. In a solenoid valve having a bearing holding member that holds the bearing, a reinforcing member that reinforces a fitting portion of the bearing holding member that fits into a mounting hole of the housing is coupled.

According to the invention of claim 3, a housing having a valve seat in the middle of a flow path of a fluid, a solenoid fixed to the housing, a valve shaft axially slid by the solenoid, and the valve. A valve body provided at the end of the shaft for opening and closing the valve seat by exciting and demagnetizing the solenoid, a bearing for slidably supporting the valve shaft, and a fitting hole formed in the mounting hole of the housing. In a solenoid valve having a bearing holding member that holds the bearing, a groove is provided outside a processed portion of the bearing holding member that is processed by the caulking jig.

[0016]

According to the first aspect of the invention, the step of forming a gap between the bearing holding member and the mounting hole of the housing is provided on the outer circumference of the bearing holding member, so that the outer circumference of the bearing holding member swells by caulking. This prevents the deformed portion from coming into contact with the mounting hole of the housing.

According to the second aspect of the present invention, the outer periphery of the bearing holding member is deformed by caulking by connecting the reinforcing member for reinforcing the fitting portion of the bearing holding member fitted into the mounting hole of the housing. To prevent

According to the third aspect of the present invention, the groove is provided outside the processed portion of the bearing holding member processed by the caulking jig, so that the outer periphery of the bearing holding member is deformed by the caulking process. Prevent that.

[0019]

1 to 3 show a first embodiment of a solenoid valve according to the present invention.

In each of the drawings, an electromagnetic valve 1 used as an exhaust gas recirculation valve has a housing 2 having a bearing holding member 3 assembled thereon, and a bearing holding member 3 having a solenoid portion 4 assembled on the upper surface thereof. The housing 2, the bearing holding member 3, and the solenoid portion 4 are fastened together by 5. Housing 2
An inflow path 6 through which the exhaust gas flows in and an outflow path 7 through which the exhaust gas flows out are bored in the shaft 1. The inflow path 6 and the outflow path 7 communicate with each other via a valve seat 8. This valve seat 8 is a valve body 9
Is opened and closed by moving up and down and sitting down. A mounting hole 10 for fitting the bearing holding member 3 therein is opened above the valve seat 8 as described later.

That is, the upper end of the valve shaft 11 which supports the valve body 9 is connected to the plunger 12 which is inserted into the solenoid portion 4. This plunger 12 is provided when the coil 13 of the solenoid portion 4 is not excited. , Is moved downward by the pressing force of the spring 14. That is, the valve body 9 is the coil 1
When the coil 13 is demagnetized, it is moved downward by the pressing force of the spring 14 and comes into contact with the valve seat 8.

The bearing holding member 3 is integrally molded by aluminum die-casting, and has a cooling passage 15 through which the cooling water supplied from the cooling pipe 15a flows, and a small amount of exhaust gas leaked from the outer periphery of the valve shaft 11 to the outside. And an exhaust gas escape passage 16 for allowing the exhaust gas to escape. The cooling pipe 1
5a may be formed by processing a pipe material and fitted into the opening of the cooling passage 15 of the bearing holding member 3, or may be integrally formed with the bearing holding member 3 by aluminum die casting. .

Further, in the first step portion 17a of the central hole 17 of the bearing holding member 3, the carbon bearing 18 slidably bearing the valve shaft 11 and the soot adhering to the surface of the valve shaft 11 are scraped off. The soot removing member 19 for
A gasket 20 for preventing the exhaust gas from leaking and a washer 21 for locking the bearing 18 are fitted to the second step portion 17b. The gasket 20 and the washer 21 are fitted to the second step portion 17b on the outer side and to the step portion 18a of the bearing 18 on the inner side.

The third step portion 17c of the central hole 17 is a surface to be pressed from above by a caulking jig 22 (shown by a chain line in FIG. 3), and when pressed by the caulking jig 22. As shown by the broken line, the caulking portion 23 protruding to the inner peripheral side is formed. The washer 21 is locked by the caulking portion 23, and at the same time, the gasket 20 and the bearing 1
8 also has a central hole 17 in the bearing holding member 3 via a washer 21.
Held in. Since the gasket 20 and the washer 21 serve as a cushion when the caulking portion 23 is caulked, the impact during caulking can be mitigated.

Further, on the outer periphery of the bearing holding member 3, a large diameter portion 24 (radius R in which the mounting hole 10 of the housing 2 fits) is fitted.
b) and a small diameter portion 25 (radius Rc), and a tapered step portion 26 (Rb-R) at the boundary between the large diameter portion 24 and the small diameter portion 25.
c) is provided. This large diameter portion 24 is the housing 2
Although the diameter is slightly smaller than the mounting hole 10 (radius Ra) of
The small diameter portion 25 is attached to the mounting hole 10 of the housing 2 (radius R
The diameter is sufficiently smaller than that of a) (Ra>Rb> Rc).

The inside diameter of the mounting hole 10 is the same as the conventional one.

The large diameter portion 24 is formed above the outer periphery of the bearing holding member 3 (range of dimension La), and the small diameter portion 25 is formed below the large diameter portion 24 (range of dimension Lb-La). . Therefore, the small diameter portion 25 is located outside the third step portion 17c of the central hole 17, and forms a gap S (≈Rb−Rc) between the small diameter portion 25 and the mounting hole 10 of the housing 2. As described above, the small-diameter portion 25 has a relatively small wall thickness and is made of aluminum die-casting, so that the strength is insufficient, and when the third step portion 17c of the bearing holding member 3 is caulked, the outer periphery of the small-diameter portion 25 is formed as shown in FIG. 3 As shown by the broken line in the middle, it bulges outward.

However, as described above, since the gap S is present between the small diameter portion 25 of the bearing holding member 3 and the mounting hole 10 of the housing 2, the bulging portion 27 formed by caulking on the outer periphery of the small diameter portion 25. Even if the bulge protrudes, the bulging portion 27 is prevented from coming into contact with the inner wall of the mounting hole 10. Therefore, the bearing holding member 3 is attached to the mounting hole 1 of the housing 2.
It is fitted to 0 without any trouble and is not affected by the bulging portion 27 due to the caulking process.

As described above, since the step portion 26 which forms the gap S between the bearing holding member 3 and the mounting hole 10 of the housing 2 is provided on the outer periphery of the bearing holding member 3, the bearing holding member 3 is caulked.
Even if the outer periphery of the housing expands, it is possible to prevent the deformed portion from coming into contact with the inner wall of the mounting hole 10 of the housing 2 without changing the dimensions of the housing 2. It becomes possible to integrally mold using a mold, and the manufacturing cost can be kept low.

FIG. 4 shows a second embodiment of the present invention.

In the figure, the mounting hole 10 for the bearing holding member 3 is shown.
A cylindrical reinforcing member 32 made of iron is fitted and integrally fixed to the outer periphery 31 of the fitting portion 30 that fits in the. Since the reinforcing member 32 is made of iron, which is more rigid than the aluminum die-cast bearing holding member 3, as described above, the third step portion 17c of the central hole 17 is used for the caulking jig 22.
Bearing holding member 3 when pressed and crimped by
The outer periphery 31 of the bulge is prevented from bulging outward.

The outer diameter of the reinforcing member 32 is the same as the outer diameter of the large diameter portion 24 described above, and the mounting hole 10 of the housing 2 is also the same as the conventional one.

FIG. 5 shows a third embodiment of the present invention.

In the figure, the mounting hole 10 for the bearing holding member 3 is shown.
A tubular reinforcing member 33 made of iron is insert-molded inside the fitting portion 30 that fits in the. Since the reinforcing member 33 is made of iron, which is more rigid than the bearing holding member 3 made of aluminum die-cast, as described above, the central hole 1
When the third step portion 17c of No. 7 is pressed and crimped by the crimping jig 22, the outer periphery of the fitting portion 30 is prevented from bulging outward.

The outer diameter of the fitting portion 30 is the same as the outer diameter of the large diameter portion 24 described above, and the mounting hole 1 of the housing 2
0 is the same as the conventional one.

Further, the reinforcing member 33 is not formed by insert molding, for example, an annular groove 34 is provided in the fitting portion 30 and the bearing holding member 3 is molded, and then the reinforcing member 3 is formed in this groove 34.
3 may be inserted and fixed.

FIG. 6 shows a fourth embodiment of the present invention.

In the figure, the mounting hole 10 of the bearing holding member 3 is shown.
Grooves 35 are provided on the entire circumference between the fitting portion 30 that fits in and the third step portion 17c of the central hole 17 that is caulked as described above. Thus, since the groove 35 is provided outside the third step portion 17c, when the third step portion 17c is pressed by the caulking jig 22 and caulked, the caulking portion 23 is indicated by a broken line in FIG. As shown by, the third step portion 17c is deformed so as to project inward and outward.

Therefore, when the third step portion 17c is caulked by the caulking jig 22, the stress during the caulking is prevented from propagating to the fitting portion 30 by the groove 35, and the fitting portion 30 is The outer circumference is prevented from bulging outward.

In the above embodiment, the EGR valve incorporated in the exhaust gas recirculation system is given as an example, but the present invention is not limited to this, and the present invention can be applied to solenoid valves incorporated in other devices. Of course.

Further, in the above embodiment, the bearing holding member 3 is made of aluminum die-cast and is integrally molded. However, the present invention is not limited to this, and it goes without saying that a metal other than aluminum may be integrally molded.

[0042]

As described above, according to the first aspect of the present invention, since the bearing holding member is provided with the step portion which forms a gap between the bearing holding member and the mounting hole of the housing, the bearing holding member is caulked. Even if the outer periphery of the bearing swells, it is possible to prevent this deformed portion from coming into contact with the mounting hole of the housing without changing the dimensions of the housing, and the bearing holding member can be integrally molded using a molding die. It becomes possible, and the manufacturing cost can be kept low.

Further, according to the invention of claim 2, since the reinforcing member for reinforcing the fitting portion of the bearing holding member fitted in the mounting hole of the housing is coupled, the outer periphery of the bearing holding member is deformed by caulking. This can be prevented, and the same effect as in claim 1 can be obtained.

Further, according to the invention of claim 3, since the groove is provided outside the processed portion of the bearing holding member processed by the caulking jig, the outer periphery of the bearing holding member is deformed by the caulking processing. This can be prevented, and the same effect as in claim 1 can be obtained.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a first embodiment of a solenoid valve according to the present invention.

FIG. 2 is a vertical cross-sectional view for explaining a configuration of a bearing holding member and a housing.

FIG. 3 is a longitudinal sectional view showing an enlarged main part of the present invention.

FIG. 4 is a vertical sectional view of a second embodiment of the present invention.

FIG. 5 is a vertical sectional view of a third embodiment of the present invention.

FIG. 6 is a vertical sectional view of a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solenoid valve 2 Housing 3 Bearing holding member 4 Solenoid part 10 Mounting hole 17 Central hole 18 Bearing 20 Gasket 21 Washer 22 Caulking jig 23 Caulking part 24 Large diameter part 25 Small diameter part 26 Step part 27 Swelling part 30 Fitting part 32, 33 Reinforcing member 35 Groove

Claims (3)

[Claims] 1. A housing having a valve seat in the middle of a flow path of a fluid, and a solenoid fixed to the housing,
A valve shaft that slides in the axial direction by the solenoid, a valve body that is provided at the end of the valve shaft and that opens and closes the valve seat by excitation and demagnetization of the solenoid, and a bearing that slidably supports the valve shaft. And a bearing holding member which is fitted into the mounting hole of the housing and holds the bearing by forming a gap between the mounting hole of the housing and the outer periphery of the bearing holding member. A solenoid valve having a step portion. 2. A housing having a valve seat in the middle of a flow path of a fluid, and a solenoid fixed to the housing,
A valve shaft that slides in the axial direction by the solenoid, a valve body that is provided at the end of the valve shaft and that opens and closes the valve seat by excitation and demagnetization of the solenoid, and a bearing that slidably supports the valve shaft. And a bearing holding member that fits into a mounting hole of the housing and holds the bearing by reinforcing the fitting portion of the bearing holding member that fits into the mounting hole of the housing. A solenoid valve comprising a reinforcing member joined together. 3. A housing having a valve seat in the middle of a flow path of a fluid, and a solenoid fixed to the housing,
A valve shaft that slides in the axial direction by the solenoid, a valve body that is provided at the end of the valve shaft and that opens and closes the valve seat by excitation and demagnetization of the solenoid, and a bearing that slidably supports the valve shaft. And a bearing holding member that fits into a mounting hole of the housing and holds the bearing by holding the bearing, the solenoid valve being outside the processed portion of the bearing holding member processed by the caulking jig. A solenoid valve having a groove.