JP2689066B2 - Proportional control valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a proportional control valve used in an ejection amount proportional control device for steplessly adjusting the thermal power of a pressure spray burner used in a petroleum refueling machine or the like.

[0002]

2. Description of the Related Art Although a jet amount proportional control device is not shown,
A bypass oil passage that bypasses the vicinity of the injection nozzle and returns to the tank is connected to the main oil passage that is sent to the ejection nozzle with a predetermined pressure, and a conventionally known ejection amount proportional control device is provided in this bypass oil passage. Has been. In this ejection amount proportional control device, the proportional control valve controls the pressure, and is composed of a valve body that is normally pressed against a valve seat having a through hole and an electromagnetic plunger that presses the valve body with electromagnetic force. Then, the pressing force of the valve element is changed by varying the electromagnetic force, and thereby the amount flowing through the through hole is controlled to control the pressure in the main oil passage to a predetermined pressure.

[0003]

However, in recent years, an electromagnetic pump has been used as a pressurizing means even in such a device in view of downsizing of equipment and cost.
This electromagnetic pump has a reciprocating piston,
The discharge pressure has a pulsation, and when the commercial power supply is used after being half-wave rectified, a pulsation of 50 to 60 cycles occurs. Although an accumulator is provided to absorb this pulsation, it is impossible to completely absorb the pulsation of the discharge pressure, and it is affected by the pulsation. For example, due to interference between pulsation and the control input of the proportional control valve (excitation coil input current for driving the electromagnetic plunger) or pulsation, the valve element vibrates and the amount of fluid passing through the through hole fluctuates. It is difficult to stably control the pressure in the oil passage. In particular, when the pressure in the bypass oil passage was suddenly changed (switching from the highest pressure to the lowest pressure), the valve element was left unsupported, and the valve element fluctuated significantly due to pulsating pressure, resulting in markedly unstable pressure control. .

Therefore, the present invention provides a proportional control valve that is not easily affected by pulsating pressure.

[0005]

In the proportional control valve of the present invention, the amount of fluid flowing through the through hole is changed by adjusting the pressing force of the valve body pressed by the valve seat having the through hole. a proportional control valve, the valve body, the pressing force is applied from the electromagnetic plunger through an abutment of the needle pin, the needle pin, slidably and through standing <br/> needle pin spring to the electromagnetic plunger And is opposed to the pressing force.
The valve body spring is arranged on the side opposite to the needle pin of the valve body. An orifice may be provided in the through hole formed in the electromagnetic plunger, and an orifice may be added upstream of the valve seat .

[0006]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a proportional control valve 14, which is provided in the proportional control valve device 1 shown in FIG. 3. First, the proportional control valve device 1 will be described.

As shown in FIG. 3, the proportional control valve device 1 is provided in a bypass oil passage 4 which bypasses the main oil passage 3 for supplying fuel oil (petroleum) to the nozzle 2. Before describing the proportional control valve device 1, the fuel oil supply system for the nozzles is configured such that the first pump 6 pressurizes the fuel oil to about 1 kg / cm ² and then the second pump 7 provided in series. It is pressurized to 8 to 9 kg / cm ² and sent to the nozzle 2. The proportional control valve device 1 is arranged in a bypass oil passage 4 that branches from a nozzle 2 and is connected between the first and second pumps 6 and 7 in order to vary the spray amount of this fuel oil. .

The proportional control valve device 1 is provided in the middle of the bypass oil passage 4 via the inlet joint 8 and the outlet joint 9 as described above. A check valve 10 is provided downstream of the inlet joint 8 in the forward direction with respect to the flow from the nozzle 2 to the pump side, and an accumulator (not shown) is provided further downstream. Further, a strainer 11 is arranged in the main body 12 further downstream. Above the strainer 11, a proportional control valve 14 described below is provided.

The proportional control valve 14 is particularly shown in FIGS. 1 and 2. An exciting coil 16 is wound around a bobbin 15, and a hollow hole 17 thereof has upper and lower magnetic cylinders 19 and 20 interposed therebetween. The cylinder 18 is inserted, and the upper and lower ends project from the hollow hole 17. The upper and lower magnetic plates 22 and 23 are installed on the upper and lower ends of the bobbin 15 by the upper and lower magnetic cylinders 19 and 20, respectively.

The cylinder 18 has a cylindrical shape, and an electromagnetic plunger 25 is slidably arranged therein, and a valve seat housing 27 for fixing a valve seat 26 is fixed at the lower end side in FIG. Has been done. The electromagnetic plunger 25 has a through hole 28 formed in the axial direction.
In FIG. 1 , an orifice 29 is provided at the upper end. In addition, the lower end side has a medium diameter portion 28a with an enlarged diameter.
And a large diameter portion 28b having a further enlarged diameter is formed, and the base portion 31a of the needle pin 31 is slidably arranged on the large diameter portion 28b. The base 31 of the needle pin 31
A needle pin spring 3 is provided between a and the electromagnetic plunger 25.
2 are armed.

The valve seat 26 has a through hole 33 in the center and a valve body 34 is seated therein. As described above, the valve seat 34 wraps the valve body 34 with an appropriate space 35 and a through hole 37. It is fixed to the housing 27. The valve body 34 is provided with a valve body spring 38 on the side opposite to the needle pin.

The valve seat case 40 has a container shape, an orifice 41 is formed at the center thereof, and a step portion 40a formed at the opening is engaged with a bracket 42, and the bracket 42 encloses the exciting coil 16. When the cover 43 and the screw 44 are provided so as to be fixed, the valve seat case 40 is fixed to the exciting coil 16 and the cover 43.
Will be integrated with.

The discharge side member 46 has a through hole 47 extending in the central axial direction.
The adjustment screw 48 is screwed to the upper end in FIG.
Further, an outlet joint 9 having the outlet through hole 9a protruding in a right angle direction is attached. The base portion 46a of the discharge side member 46 is inserted through the hole 49 of the cover 43, and at this time, the cylinder 18 is fitted into the through hole 47. The discharge side member 46 is covered with the screw 50 by the cover 43.
It is screwed in and fixed. When the discharge side member 46 is assembled, the spring 51 is inserted between the electromagnetic plunger 25 and the adjusting screw 48 and is elastically mounted. this
The spring 51 has a larger pressing force than the valve body spring 38.
Have.

Therefore, the spring 51 presses the electromagnetic plunger 25 downward in FIG. 1, so that the tip of the needle pin 31 abuts the valve element 34 and presses it against the valve seat 26. The pressing force on the valve element 34 is adjusted by screwing the adjusting screw 48 and by changing the current to the exciting coil 16. The valve body 3
4 is pressed toward the needle pin 31 side by the valve body spring 38 , and the valve body 34 is pressed from both sides (up and down). 5
Reference numeral 2 is a terminal for the exciting coil 16.

In the above-mentioned structure, the exciting coil 16 of the proportional control valve 14 is driven by a constant current, and a predetermined constant current for controlling is supplied with a current in which a smaller rectangular wave pulse current of about 130 Hertz is superimposed. To be done. As the current increases, the pressing force with which the needle pin 31 presses the valve body 34 against the valve seat 26 becomes stronger. Further, when the current becomes smaller, the pressing force from the needle pin 31 to the valve body 34 becomes weaker.

Such a change in the pressing force applied to the valve element 34 causes
The amount of the fluid passing through the through hole 33 is changed, and thereby the pressure in the main oil passage 3 can be controlled. The fluid in the main oil passage 3 has a pulsation by the pump, and this pulsation tries to vibrate the valve element 34, but since the valve element spring 38 presses and holds it toward the needle pin 31 side, The influence is reduced and the amount of vibration is much smaller than before, and the control pressure can be controlled stably. And when changing the set pressure greatly, for example, even when changing from the maximum pressure to the minimum pressure, the valve
Since the body spring 38 extends and follows, the valve body 34 does not fluctuate (flutter) due to pulsation, and stable control can be performed. And, depending on the orifice 29,
The pulsating pressure moves the electromagnetic plunger 25 in the direction of compressing the spring 51 to expand the space between the plunger 25 and the valve seat housing 27 to absorb the pulsation.
Further, the orifice 41 delays and smoothes the pulsating wave.

[0017]

As described above, according to the present invention, the valve body is used as the valve body during the proportional control of the fluid in which the pulsating pressure remains.
It is sandwiched and supported by a needle pin added by a spring for use and a needle pin spring, and a desired flow rate can be stably passed without being affected by pulsation due to pulsating pressure. As a result, stable fuel control is possible. In addition, it was installed in the through hole of the electromagnetic plunger.
By the orifice, and further upstream than the valve seat
Pulsation by orifices arranged in is smoothed, the valve body
Flapping can be prevented.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is a configuration diagram showing a proportional control valve device in which the present invention is used and an example in which the proportional control valve device is used in a pressure spray burner circuit.

[Brief description of reference numerals]

DESCRIPTION OF SYMBOLS 1 Proportional control valve device 4 Bypass oil passage 14 Proportional control valve 16 Excitation coil 25 Electromagnetic plunger 26 Valve seat 28 Through hole 26 Orifice 31 Needle pin 32 Needle pin spring 34 Valve body 38 Valve body spring 41 Orifice

Claims (3)

(57) [Claims] 1. In a proportional control valve in which the amount of fluid flowing through the through hole is changed by adjusting the pressing force of the valve body pressed against the valve seat having the through hole, the valve body is abutting. pressing force is applied from the electromagnetic plunger through the needle pin, the needle pin, needle pin solenoid plunger
Together disposed slidably and through standing the use springs, proportional control valve the valve body spring opposite to the pressing force, characterized in that arranged in the counter-needle pin side of the valve body. 2. The proportional control valve according to claim 1, wherein an orifice 29 is provided in a through hole formed in the electromagnetic plunger. 3. An orifice upstream of the valve seat.
The proportional control valve according to claim 1, wherein 41 is arranged.