JPH1113604A - Electromagnetic air control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve assembling operability of a diaphragm by sandwiching a center part of the diaphragm by an abutting part between a trailing end of a valve body and a leading end of a movable core, and sandwiching its outer peripheral part by an abutting part between a valve body and a housing. SOLUTION: An outer peripheral part 13B of a diaphragm 13 forming a pressure cancel chamber A is sandwiched and fixed by an abutting part K2 between a bottom 4B of a housing 4 and a bottom 1E of a housing hole 1B of a valve body 1, when the housing 4 is press-fitted into the housing hole 1B. A center part 13A of the diaphragm 13 is sandwiched and fixed by an abutting part K1 between a leading end 9A of a movable core 9 and a trailing end 12B of a valve body 12 when the valve body 12 is press-fitted into the movable core 9. The abutting part K1 for fixing the diaphragm center part 13A is formed in the vicinity of an upper side wall 2Ba of a secondary side flow passage 2B. Therefore, when air is flowed into the secondary side flow passage 2B from a primary side flow passage 2A, flexure occurrence is prevented which may otherwise generated by air flow in the diaphragm 13. Its durability is thus improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine for controlling the amount of auxiliary air flowing in an auxiliary air passage formed around a throttle valve arranged in an intake passage of a throttle body in accordance with an electric signal. The present invention relates to an electromagnetic air control valve.
This electromagnetic air control valve is a normally closed type and mainly adjusts the idling air amount of the engine.

[0002]

2. Description of the Related Art A conventional electromagnetic air control valve in an internal combustion engine is disclosed in Japanese Patent Application No. 7-2065 filed by the present applicant.
No. 24 exists. According to this, the air flow passage formed in the valve body is divided into a primary flow passage and a secondary flow passage by a valve seat, and is arranged facing the secondary flow passage so as to face the valve seat. An electromagnetic air control valve in an internal combustion engine that controls an amount of air flowing through an air flow path by controlling a valve body according to an electric signal applied to an electromagnetic device, and is disposed in a secondary flow path. The connecting rod has a valve body at one end thereof for opening and closing a valve seat, and a movable core opposite to a fixed core constituting an electromagnetic device at the other end. A guide hole is formed along the longitudinal axis thereof, and a guide rod that is movably inserted into the guide hole is formed at the movable core side facing end of the fixed core so as to protrude therefrom.
In the secondary flow path, there is disposed a partition composed of an annular diaphragm forming a pressure canceling chamber. Is fitted and arranged in an annular groove formed in the outer periphery of the valve body and fixed. The pressure in the primary side channel is introduced into the pressure canceling chamber through a pressure hole formed in the valve body. The provision of the pressure cancel chamber is necessary to balance the fluid pressure applied before and after the valve element.

[0003]

According to such a conventional electromagnetic air control valve, the inner peripheral portion of the diaphragm is fitted and disposed in an annular groove formed in the outer periphery of the valve body. In this case, the inner peripheral portion of the diaphragm is expanded and mounted in the annular groove, and thereafter, the elastic return force of the inner peripheral portion is used. When the elastic restoring force of the diaphragm is increased, the fitting degree is good but the fitting operation becomes extremely difficult, and the productivity is greatly impaired. On the other hand, when the elastic return force of the diaphragm is reduced,
Good fit to the annular groove cannot be obtained. Therefore, the fitting of the inner periphery of the diaphragm into the annular groove must be set very carefully. Temporarily, in order to reliably perform the fitting, it is considered to attach a fastening member such as a ring member around the inner peripheral portion of the diaphragm fitted and arranged in the annular groove. The number of fitting work steps and the number of parts increase, which leads to an increase in manufacturing cost, which is not preferable.

Further, according to the conventional example, the diaphragm forming the partition body is disposed so as to be largely immersed in the secondary flow path. According to this, when the valve element opens the valve seat and air flows into the secondary flow path from the primary flow path, the diaphragm moves to the second position.
The diaphragm receives the pressing force due to the air flow in the secondary flow path, and the diaphragm continuously bends.When used for a long period of time, the shape and rigidity of the diaphragm to prevent the diaphragm from being damaged. The material etc. needs to be selected very carefully.

[0005] The electromagnetic air control valve according to the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an electromagnetic air control valve excellent in workability of assembling a diaphragm forming a pressure cancellation chamber. And the shape and rigidity of the diaphragm,
To provide an electromagnetic pneumatic control valve capable of increasing the degree of freedom of material selection. With the goal.

[0006]

In order to achieve the above object, the electromagnetic air control valve according to the present invention has a fixed core fixedly disposed inside an electromagnetic coil disposed in a housing, and is opposed to the fixed core. Electromagnetic air that controls opening and closing of a valve seat that divides a valve body into a primary side flow path and a secondary side flow path by a valve body in which a movable core is movably arranged and moves synchronously with the movable core. In the control valve, the movable core is movably supported by a guide rod provided upright on the fixed core, and a valve body having a valve portion for opening and closing a valve seat at a distal end portion has a rear end integrated with the movable core. The center of the diaphragm for pressure control is clamped at the contact portion between the rear end of the valve body and the tip of the movable core, and the outer peripheral portion is fixed by the contact portion between the valve body and the housing. A pressure cancel chamber is formed by sandwiching Facing the Nseru chamber to the primary side flow passage and the first, characterized in that an opening.

[0007] In addition to the first feature, the present invention has a second feature in that a contact portion between the rear end of the valve body and the movable core is disposed close to the electromagnetic device side.

[0008]

According to the first feature of the electromagnetic air control valve of the present invention, the center of the diaphragm forming the pressure canceling chamber is sandwiched by the contact portion between the rear end of the valve body and the front end of the movable core. Since the outer peripheral portion is sandwiched by the contact portion between the valve body and the housing, the workability of assembling the diaphragm and the stable sealing of the pressure cancel chamber can be obtained.

According to a second feature of the electromagnetic pneumatic control valve of the present invention, a contact portion between the rear end portion of the valve body and the movable core is disposed close to the electromagnetic device side, and the contact portion is provided at the contact portion. Since the central portion of the diaphragm was sandwiched, the degree of opening of the diaphragm to the secondary flow path could be reduced, thereby increasing the degree of freedom in selecting the diaphragm.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of an electromagnetic air control valve according to the present invention. Reference numeral 1 denotes a valve body in which an air flow path is bored, and the air flow path is divided by a valve seat 3 into a primary flow path 2A and a secondary flow path 2B. A housing housing hole 1B facing the secondary flow path 2B is formed open at 1A (upper side in the figure), and a female screw facing the primary side flow path 2A at the tip 1C of the valve body 1 (lower side in the figure). A hole 1D is drilled. S is an electromagnetic device and is composed of the following. Reference numeral 4 denotes a housing having a bottomed cylindrical shape with an open upper portion. A cylindrical coil bobbin 5 having flanges formed at both ends is housed and arranged in the housing 4, and an electromagnetic coil is provided around the outer periphery of the coil bobbin 5. 6 is wound. Reference numeral 7 denotes a fixed core, and an annular portion 7A that is disposed in the inner cylinder of the coil bobbin 5 and protrudes from the upper end of the coil bobbin 5 is fixedly disposed on the locking step 4A of the housing 4. Reference numeral 8 denotes a guide rod, which is fixedly disposed concentrically with the fixed core 7 along the longitudinal axis of the fixed core 7, and the lower end of the guide rod 8 protrudes further below the lower end of the fixed core 7. .

Reference numeral 9 denotes a movable core which is disposed to face the fixed core 7. At the center of the movable core 9, a bearing press-fitting hole 9A having a bottom is drilled downward from the upper end.
The linear bearing 10 is disposed in the bearing press-fit hole 9A. The linear bearing 10 is supported by a guide rod 8. Thus, the movable core 9 is arranged concentrically with respect to the fixed core 7 and movably supported by the guide rod 8. Reference numeral 11 denotes a first spring contracted between the fixed core 7 and the movable core 9, and serves to separate the movable core 9 from the fixed core 7.

Reference numeral 12 denotes a valve element fixedly disposed at the distal end of the movable core 9. A valve section 12A for opening and closing the valve seat 3 is provided at the distal end of the valve element 12. Reference numeral 13 denotes an annular pressure control diaphragm, which is provided with the movable core 9 and the valve body 1 described above.
2 and the mounting of the diaphragm 13 are performed as follows.

That is, an annular flat portion 9B is formed at the tip 9A of the movable core 9, and has a diameter smaller than the diameter of the movable core 9 than the annular flat portion 9B. A small-diameter cylindrical portion 9C is formed to protrude further downward. On the other hand, valve element 1
A press-fit hole 12C into which the small-diameter cylindrical portion 9C of the movable core 9 can be press-fitted is formed in the rear end portion 12B of the movable core 9 downward.

The annular diaphragm 13 has an annular central portion 13A at the center thereof, and an annular outer peripheral portion 13A at the outside thereof.
B, and the small-diameter cylindrical portion 9C of the movable core 9 is
When press-fitting into the press-fitting hole 12C of the second
The central portion 13A of the diaphragm 13 is sandwiched and fixed between the distal end portion 9A of the diaphragm 13 and the rear end portion 12B of the valve body 12.

Reference numeral 12D denotes a pressure hole formed in the valve body 12, the tip of which is located at the distal end of the valve body 12 and the valve portion 1D.
It opens inside 2A, and the rear end opens at the bottom of the press-fit hole 12C. Reference numeral 9D denotes a pressure hole formed in the movable core 9, the front end of which is open at the front end of the small-diameter cylindrical portion 9C, and the rear end thereof is the outer periphery of the movable core 9 (the front end 9A of the movable core 9). It opens to the outer periphery on the more rear end side).

Next, the assembly of the electromagnetic air control valve will be described. First, before assembly, the electromagnetic device S and the sub-assembly of the movable core 9 are formed. Electromagnetic device S
The electromagnetic coil 6 extends from the opening of the housing 4 to the bottom.
The fixed core 7 having the guide rod 8 is inserted toward the inside of the coil bobbin 5, and the annular portion 7A of the fixed core 7 is 4A, and in this state, the rear end of the housing 4 is bent inward toward the annular portion 7A and is caulked.

Movable core 9 with linear bearing 10
Is fixed to the movable core 9 and the valve body 12 by being press-fitted into the press-fit hole 12C of the valve body 12, and at this time, the annular flat portion 9B of the distal end 9A of the movable core 9 is formed. The central portion 13A of the diaphragm 13 is clamped and fixed by the contact portion K1 with the rear end portion 12B of the valve body 12, whereby the movable core 9 and the valve body 12 and the diaphragm 13 are integrally fixed. And in the said, the valve body 1
The second pressure hole 12D and the pressure hole 9D of the movable core 9 communicate with each other. The distal end of the pressure hole 12D opens at the distal end of the valve body 12, and the pressure of the movable core 9 that communicates with the pressure hole 12D. The rear end of the hole 9D opens on the outer periphery of the movable core 9.

Then, the sub-assembly of the movable core 9 is inserted and arranged in the valve main body 1. Specifically, the secondary side flow path 2 </ b> B through the housing accommodation hole 1 </ b> B of the valve body 1.
The sub-assembly of the movable core 9 is inserted toward the valve body 12, the valve portion 12A of the valve body 12 is arranged facing the valve seat 3, and the outer peripheral portion 13B of the diaphragm 13 is placed on the bottom 1E of the housing storage hole 1B. Be placed.

Next, the housing 4 of the electromagnetic device S is press-fitted into the housing receiving hole 1B, and the electromagnetic device S is fixed to the valve body 1. At this time, the diaphragm 13
The outer peripheral portion 13B is sandwiched and fixed by a contact portion K2 between the bottom portion 1E of the housing storage hole 1B and the bottom portion 4B of the housing 4. When the electromagnetic device S is mounted on the valve body 1, the first spring 11 is contracted and arranged between the fixed core 7 and the movable core 9. The body 12 is pressed toward the distal end, and the valve portion 12A is pressed against the valve seat 3.

On the other hand, in the diaphragm 13, the central portion 13A is clamped and fixed by the contact portion K1 between the front end portion 9A of the movable core 9 and the rear end portion 12B of the valve body 12, and the outer peripheral portion 13B is fixed. The pressure cancel chamber A is sandwiched and fixed by an abutting portion K2 between the bottom 4B of the housing 4 and the bottom 1E of the housing storage hole 1B, whereby a pressure canceling chamber A isolated from the secondary flow path 2B is formed separately. . The pressure canceling chamber A was opened and communicated with the primary flow path 2A via the pressure holes 9D and 12D.

Reference numeral 14 denotes a second spring whose rear end is in contact with the distal end of the valve body 12 and whose distal end is in contact with an adjusting screw 15 screwed into the female screw hole 1D. Energize to the more open side. The spring force of the second spring 14 is set smaller than the spring force of the first spring 11, and the valve 12 A closes the valve seat 3 by screwing the adjustment screw 15. Adjust the force. (After the adjustment, the spring force of the first spring 11 is larger than the spring force of the second spring 14).
Reference numeral 16 denotes an annular retainer, which is a diaphragm 1
3 and is disposed on the outer periphery of the diaphragm 13.
Is prevented from directly acting on the outer peripheral portion of the air flow flowing in the secondary flow path 2B.

When the electromagnetic coil 6 is not energized, no magnetic force is generated in the electromagnetic device S. According to this, the movable core 9 including the valve element 12 is connected to the first spring 1
Since it is pressed downward in the figure by the spring force of 1,
The valve portion 12A closes and holds the valve seat 3. Therefore, air does not flow from the primary flow path 2A to the secondary flow path 2B via the valve seat 3. In this state, the guide rod 8 movably supports the movable core 9 including the diaphragm 13 and the valve element 12 via the linear bearing 10.

When a current flows through the electromagnetic coil 6,
A magnetic circuit is formed by the fixed core 7, the housing 4, and the movable core 9, and a magnetic force is generated in accordance with the supplied current, and the movable core 9 is attracted to the fixed core 7. Meanwhile, the first
The spring 11 gives resistance to the moving movement of the movable core toward the fixed core 7. Accordingly, at a position where the magnetic force in the electromagnetic device S and the drag force of the first spring 11 are balanced, the moving position of the movable core 9 is determined,
Thus, the opening position of the valve seat 3 by the valve body 12 is controlled, and the amount of air corresponding to the opening of the valve seat 3 is changed from the primary side flow path 2A to 2
It flows toward the secondary flow path 2B.

Here, the outer peripheral portion 13B of the diaphragm 13 forming the pressure canceling chamber A is formed in the housing accommodation hole 1B.
When press-fitting the housing 4 into the
4B and bottom 1 of housing housing hole 1B of valve body 1
It is pinched and fixed by the contact portion K2 with E. On the other hand, when press-fitting the valve element 12 into the movable core 9, the central portion 13 </ b> A of the diaphragm 13
A is sandwiched and fixed by the contact portion K1 between A and the rear end portion 12B of the valve element 12. According to the above, the pressure cancellation chamber A can be made extremely easy and can be reliably isolated from the secondary flow path 2B.

In particular, the central portion 13A of the diaphragm 13 is securely fixed by being clamped by the contact portion K1 between the front end portion 9A of the movable core 9 and the rear end portion 12B of the valve element 12. Since the fixing is performed by the movable core 9 and the valve body 12, which are indispensable members of the electromagnetic air control valve, it is not necessary to prepare a special member for fixing the central portion 13A.

Attention is also paid to the contact portion K1 for sandwiching the central portion 13A of the diaphragm 13.
Is located in the vicinity of the upper side wall 2Ba of the secondary side flow path 2B and is disposed close to the electromagnetic device S side. In other words, the diaphragm 13 is located at an upper position in the drawing of the secondary flow path 2B, and does not sink deeply into the secondary flow path 2B. According to the above, when air flows into the secondary flow path 2B via the primary flow path 2A, the diaphragm 13 does not receive the pressing force due to the air flow in the secondary flow path 20.
The flexure caused by the air flow in the diaphragm 13 can be suppressed as much as possible. Therefore, during long-term use, the durability of the diaphragm 13 can be significantly improved,
Further, the degree of freedom in selecting the material, shape, rigidity, and the like of the diaphragm 13 can be increased.

[0027]

As described above, according to the electromagnetic air control valve of the present invention, the central part of the pressure control diaphragm is
Since the pressure cancel chamber is formed by sandwiching the contact portion between the rear end portion of the valve body and the tip end portion of the movable core and the outer peripheral portion by the contact portion between the valve body and the housing, the center of the diaphragm is formed. The portion and the outer peripheral portion can be securely fixed without preparing a special member, and the pressure canceling chamber securely isolated from the secondary flow path can be formed extremely easily and at low cost.

Further, according to the arrangement of the contact portion between the rear end portion of the valve element and the front end portion of the movable core close to the electromagnetic device, the diaphragm is affected by the flow of air flowing through the secondary flow path. This makes it possible to greatly improve the durability of the diaphragm and increase the degree of freedom in selecting the diaphragm.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of an electromagnetic air control valve according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve main body 3 Valve seat 4 Housing 9 Movable core 12 Valve body K1 Contact part between the rear end part of valve body and the front-end part of movable core K2 Contact part between valve body and housing A Pressure cancellation chamber S Electromagnetic device

Claims (2)

[Claims] 1. A valve body in which a fixed core is fixedly disposed inside an electromagnetic coil disposed in a housing, a movable core is movably disposed facing the fixed core, and moves synchronously with the movable core. In the electromagnetic air control valve that controls opening and closing of a valve seat that divides the valve body into a primary flow path and a secondary flow path, the movable core 9 is connected to the guide rod 8 erected on the fixed core 7. The valve body 12 which is movably supported and has a valve portion 12A which opens and closes the valve seat 3 at the front end portion has a rear end portion integrally fixed to the movable core 9, and has a central portion 13A of a diaphragm 13 for pressure control. At the contact portion K1 between the rear end portion 12B of the valve element 12 and the distal end portion 9A of the movable core 9, and the outer peripheral portion 13B of the contact portion K2 between the valve body 1 and the housing 4. Pressure cancellation chamber A
Wherein the pressure cancellation chamber is opened to face the primary side flow path 2A. 2. The electromagnetic air control valve according to claim 1, wherein a contact portion K1 between the rear end portion 12B of the valve body and the movable core 9 is arranged close to the electromagnetic device S side.