JPH034867Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an electromagnetic flow control valve, and in particular, it includes a bobbin used in the control valve, an electromagnetic coil wound around the bobbin, and a bobbin holder press-fitted into the bobbin. This invention relates to an electromagnetic flow control valve that is integrated with a synthetic resin material.

The electromagnetic flow control valve is configured to open and close a slide valve using an electromagnetically operated linear motor, thereby making it possible to supply a flow rate approximately proportional to the applied current. The electromagnetic flow control valve is
It is often used in exhaust gas purification equipment, but in this case,
The input port is connected to the air pump and the output port is connected to the upstream side of the three-way catalyst in the exhaust system, and the current applied to the control valve is changed by signals according to the negative pressure, temperature, rotation speed, etc. of the engine. It functions to supply the air necessary for achieving the most preferable exhaust gas concentration for the main catalyst to the exhaust gas purification system.

A linear motor used in such an electromagnetic flow control valve consists of a hollow core having a long hole leading to an output port, a bobbin that slides along the hollow core, an electromagnetic coil wound around the bobbin, and an electromagnetic coil wound around the bobbin. It has a bobbin holder, a magnet, and a magnetic yoke that are press-fitted. A bobbin (slide valve), electromagnetic coil and bobbin holder slide along the hollow core to control fluid flow.
Repetition of this sliding motion causes the electromagnetic coil to become loose and the pressing force of the bobbin holder to the bobbin to become weak, making it impossible for the linear motor to move in a predetermined manner.

This idea focuses on the points mentioned above, and includes coating the electromagnetic coil and bobbin holder with resin, allowing the resin to flow into the outer peripheral surface of the bobbin through holes drilled in the bobbin holder, and in addition, By using technical means to firmly fix the electromagnetic coil and bobbin holder to the bobbin together with the resin flowing in from the resin, the above-mentioned conventional problems are solved.

According to this invention, in the electromagnetic flow rate proportional control valve that controls communication of the input port communicating with the air pump, which is always in communication with the second output port communicating with the atmosphere, with the first output port communicating with the exhaust system by means of a slide valve, An electromagnetic coil wound around a bobbin that slides along a hollow core constituting a linear motor and a bobbin holder press-fitted into the bobbin are coated with a resin material, and the resin material is applied between the electromagnetic coils and between the bobbin holder. An electromagnetic flow control valve is provided that allows flow to flow into the outer circumferential surface of the bobbin through a plurality of bored holes.

An embodiment of this invention will be described with reference to the accompanying drawings.

The electromagnetic flow control valve 1 shown in the figure has a linear motor 3 housed in a case 2. The linear motor 3 has a hollow core 5 that is press-fitted into the outlet passage 4 of the case 2 . A first valve hole 6 and a second valve hole 7 in the form of long holes are bored in the hollow core 5 at separate positions, and a blind plug is inserted between the first valve hole 6 and the second valve hole 7. 8 will be provided. The hollow core 5 is formed by punching a first valve hole 6 and a second valve hole 7 in a flat plate and then winding it into a pipe shape. The outlet passage section 4 communicates with a second output port 9 that is open to the atmosphere. The inlet portion 11 of the case 2 leading to the input port 10 of the cover 31 is
It is a relatively large space, and the entrance section 11 is
Via the valve hole 7, there is constant communication with the second output port 9. The inlet portion 11 can further communicate with the second output port 9 via the relief valve 12 . When the pressure from the input port 10 leading to the air pump increases, the relief valve 12 opens and releases the pressure at the inlet 11 to the second output port 9. The relief valve 12 is normally closed by the force of the spring 13. A pressure receiving plate 15 is fixed to the valve body 14. The pressure receiving plate 15 has a high pressure at the inlet portion 11.
When the valve body 14 moves to the right to open the valve hole 16 against the biasing force of the spring 13, it receives pressure from the inlet portion 11, thereby preventing minute vibrations of the valve body 14.

A magnetic yoke 18 having a magnet 17 fixed to its inner circumferential side is press-fitted into one end of the hollow iron core 5. Further, on the hollow core 5, a spring holder 19, a bobbin 20, and an electromagnetic coil 2 fixed to the bobbin 20 are provided.
1 and a bobbin holder 22 are slidably disposed. After adjusting the position of the spring holder 19,
It is fixed to the case 2 by a seal body 23 made of resin. The bobbin holder 22 that receives the biasing force of the spring 24 serves as a slide valve for the bobbin 20.
to the left to close the valve hole 6 and cut off communication between the input port 10 leading to the air pump and the first output port 25 leading to the exhaust system. In this state, the valve hole 7 is open, and fluid from the input port 10 flows out through the valve hole 7 to the second output port 9.

An electromagnetic coil 21 is wound around the bobbin 20,
Then, the bobbin holder 22 is press-fitted. The bobbin holder 22 has an annular wall on one side that receives the spring 24, and has a plurality of holes 26 formed in its cylindrical portion.

The outer peripheral surfaces of the electromagnetic coil 21 wound around the bobbin 20 and the bobbin holder 22 press-fitted therein are coated with synthetic resin. This resin flows into the outer peripheral surface of the bobbin 20 from between the electromagnetic coils 21, and the resin that has entered the hole 26 of the bobbin holder 22 flows into the outer peripheral surface of the bobbin 20. Furthermore, the resin is spring 2
4 and the electromagnetic coil 21 is formed. Considering the strength of the thin-walled bobbin 20 made of aluminum alloy material, the press-fitting allowance for the bobbin holder 22 is set small; bobbin 20
This strengthens the press fit and makes it more integrated. The resin flowing between the electromagnetic coils 21 also bonds the coils to each other and adheres the coils to the bobbin 20.
In this way, the bobbin 20, the electromagnetic coil 21 and the bobbin holder 22 are integrated, and in addition, the contact 2
7 is protected by a resin layer 28.

The sealing material 29 attached to the magnetic yoke 18 is
It has the function of a stopper 30 for the bobbin 20. A cover 31 including an input port 10 and a first output port 25 is fixed to the case 2 using screws 32. The sealing material 29 ensures airtightness around the magnetic yoke 18. Note that the outer circumferential curl portion 33 of the magnetic yoke 18 is press-fitted into the inner wall surface of the case 2. Further, the electromagnetic coil 21 is connected to an external power source via a conductive spring 24.

When the current is not energized as shown in the figure, a closed loop magnetic circuit is formed by the magnetic flux from the permanent magnet 17 via the iron core 5 and the magnetic yoke 18, and a part of the circuit is connected to the electromagnetic coil 21. When the voltage is applied, a force proportional to the current value is generated in the right direction in the figure according to Fleming's left hand rule, and the bobbin 20 is actuated and displaced in the right direction against the biasing force of the spring 24, causing the bobbin 20 to move into the valve hole. 6 is opened by an amount proportional to the applied current, and the input port 10 is connected to the first
allows fluid flow to output port 25 of.

At this time, when the pressure at the inlet increases to a predetermined value or more, the relief valve 12 opens and releases the increased pressure to the second output port 9.

[Brief explanation of the drawing]

The figure is a sectional view of an electromagnetic flow control valve as an example of this invention. In the diagram: 1...Solenoid flow control valve, 2...Case, 3...Linear motor, 5...Hollow iron core, 6,
7... Valve hole, 9... Second output port, 10...
Input port, 12... Relief valve, 17... Magnet, 18... Magnetic yoke, 20... Bobbin, 2
1... Electromagnetic coil, 22... Bobbin holder, 2
5...First output port, 26...hole, 28...
resin layer.

Claims (1)

[Scope of utility model registration request] a case having a second output port communicating with the atmosphere, an input port constantly communicating with the second output port and communicating with the air pump, and a first output port communicating with the exhaust system; the input port and the first output; a hollow iron core supported by the case and having a first valve hole 6 for controlling communication with the port and a second valve hole 7 for constantly communicating the input port and the second output port; a bobbin that is slidable along a hollow iron core to control opening and closing of the first valve hole; an electromagnetic coil wound around the bobbin; a bobbin holder fixed to the bobbin; and a bobbin facing the electromagnetic coil. a permanent magnet; and a magnetic yoke having at least one end supported on the hollow core side, the electromagnetic coil and the bobbin holder are coated with a resin material, and the resin material is arranged between the electromagnetic coils and the bobbin. An electromagnetic flow control valve characterized in that the flow is caused to flow into the outer peripheral surface of the bobbin through a plurality of holes formed in a holder.