JPS638482B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pressure control valve that accurately controls the gas pressure supplied to the burner of a gas combustion device using an electric signal, and in particular, it is capable of stable control without causing valve vibration. A pressure control valve is provided.

FIG. 1 shows a conventional example. A fluid inlet 1, an outlet 2, and a valve seat 3 are formed in the body 12, and a diaphragm 5
is installed, the valve body 4 is fastened to the diaphragm 5,
It faces the valve seat 3 and constitutes a governor section. The center upper part of the valve body 4 passes through the diaphragm 5 and is in contact with the end surface of the push rod 13. A damper diaphragm 21 is attached to the lower part of the body 12, and a valve body 4 is installed in the center of the damper diaphragm 21.
Insert and secure the mounting part that extends from. Reference numeral 22 is a lower lid that presses down the outer peripheral portion of the damper diaphragm 21 and forms a damper chamber B. A damper hole 15 is provided in the damper diaphragm 21. 2
3 is a diaphragm presser.

The plunger 7, coil 8, and yokes 9, 10 constitute an electromagnetic force generating section. The plunger 7 is supported coaxially with the coil 8 by two leaf springs 11 at its upper and lower parts, and moves up and down without sliding. Reference numeral 13 denotes a push rod made of a non-magnetic material, and its lower end surface contacts the upper center of the valve body 4. 16 and 17 are upper and lower leaf spring mounting bases, respectively. Reference numeral 18 denotes an operating point adjustment spring that acts to push the plunger 7, one end of which abuts an adjustment screw 19, and the adjustment screw 19 is screwed into the lid 20.

In this configuration, when a current is passed through the coil 8, a downward electromagnetic force is generated in the plunger 7 depending on the magnitude of the current, and the push rod 13 acts to push the valve body 4. According to the well-known governor principle, the pressure P ₂ of the fluid flowing out from the outlet 2 is determined by the force acting on the valve body. That is, the pressure P ₂ can be arbitrarily changed within a certain range by changing the current value passed through the coil 8.

The damper chamber B suppresses the rapid movement of the valve 4, that is, the rapid movement of the diaphragm 5. In other words, a positive or negative pressure is generated in the damper chamber relative to the pressure P ₂ , and this pressure constantly acts on the movement of the valve body 4 in the opposite direction to the movement direction (hereinafter referred to as
(referred to as damper action). However, in the conventional example, although vibrations caused by the fluid pressure and the masses of the valve and plunger can be prevented, unstable operation phenomena occur due to the eccentricity of the damper diaphragm 21.

In other words, a misalignment occurs between the axis of the valve seat 4 and the axis of the valve element 4, which is vertically supported by the diaphragm 5 and damper diaphragm 21, causing the valve element 4 to slide on the valve seat 3, causing friction. The resistance increases the hysteresis in the characteristic of outlet pressure versus current value. This misalignment between the axes of the valve seat and the valve body is caused by the mounting part 2 of the diaphragm 5 and the damper diaphragm
It is thought that this is caused by variations in the mutual position of parts due to the processing accuracy of the parts 4, 25 and the valve seat 3, or by misalignment during assembly.

Another possible vibration prevention method is to provide a damper chamber on the atmosphere side of the diaphragm, as used in conventional gas governors. Figure 2 shows its configuration. A damper chamber B is provided on the atmosphere side of the diaphragm 5 and communicates with the atmosphere through a damper hole 15. In this case, if the volume of the damper chamber is too large, the damper effect will be weak and vibrations will not be prevented. Therefore, when the electric drive section is attached to the gas governor section, the electric drive section is required to be devised to reduce the volume of the damper chamber, resulting in a complicated configuration.

The present invention prevents vibration without increasing such hysteresis or requiring a complicated configuration of the electric drive unit.
Moreover, a pressure control valve with stable operation is realized.

FIG. 3 shows an embodiment of the present invention. body 12
A fluid inlet 1, an outlet 2, and a valve seat 3 are formed in the diaphragm 5, and a diaphragm 5 is attached to the diaphragm 5.
are fastened together to form a governor section facing the valve seat 3.
The upper central portion of the valve body 4 passes through the diaphragm 5 and abuts against a contact portion 6 at the center of the damper diaphragm 21 . The damper diaphragm 21 is provided opposite to the diaphragm 5 constituting the governor section,
It constitutes the damper chamber. Its effective diameter is larger than that of the diaphragm 5. 14 is a diaphragm presser.

The damper diaphragm 21 has a damper hole 15.
will be established. As in the conventional example, the electric drive section includes the plunger 7, coil 8, and yokes 9 and 10, which constitute an electromagnetic force generating section. The plunger 7 is supported coaxially with the coil 8 by two leaf springs 11 at the upper and lower parts.
Moves up and down without sliding. Reference numeral 13 denotes a push rod made of non-magnetic material, and its lower end surface is in contact with the upper center of the valve body 4. 16 and 17 are upper and lower leaf spring mounting bases, respectively. Reference numeral 18 denotes an operating point adjustment spring that acts to push the plunger 7, one end of which abuts an adjustment screw, and the adjustment screw 19 is screwed into the lid 20.

Next, the operation of the present invention will be explained.

When current is passed through the coil 8, an electromagnetic force is generated and acts to push the plunger 7 downward. This electromagnetic force changes depending on the magnitude of the current. This electromagnetic force acts so that the push rod 13 pushes the valve body 4. According to the well-known governor principle, the pressure P ₂ of the fluid flowing out from the outlet 2 is determined by the force acting on the valve body. In other words, the pressure is determined by the current value flowing through the coil 8.
P ₂ can be changed arbitrarily within a certain range.

The damper chamber B has a damper effect to suppress rapid movement of the valve 4. In other words, when the valve 4 moves rapidly, that is, when the diaphragm 5 moves rapidly, there is a difference in the effective diameters of the diaphragm 5 and the damper diaphragm 21, so a positive or negative pressure relative to the atmospheric pressure is created in the damper chamber. cause
The pressure acts constantly on the diaphragm 5 in a direction opposite to its direction of movement.

This is effective in preventing valve vibration.
The magnitude of the damper action can be set by the size of the damper hole 15. Therefore, it is designed to satisfy the effect of vibration prevention and to have virtually no problem in response of the outlet pressure to changes in the coil current.

According to the present invention, the damper diaphragm 21 operates in the pressure control operation state of the valve body 4 of the governor section.
Do not impose unstable regulations on this movement. For this reason,
Unlike the conventional example, no increase in hysteresis or unstable operation occurs in the characteristic of outlet pressure with respect to current value due to frictional resistance between the valve body 4 and the valve seat 3.

Furthermore, since the damper diaphragm 21 is provided in the governor section to constitute the damper chamber, the electric drive section does not require a complicated structure unlike other conventional examples. Therefore, any electric drive can be installed as is.

Note that in the present invention, the damper diaphragm 21
Although the effective diameter of the diaphragm 5 is larger than that of the damper diaphragm 21, the same effect can be obtained even if the damper diaphragm 21 is made smaller.
This is the diaphragm 5 that constitutes the damper chamber B.
If the effective diameter of the damper diaphragm 21 is different from that of the damper diaphragm 21, even if the effective diameter of the damper diaphragm 21 is made small, a volume change in the damper chamber B will occur due to the rapid movement of the valve body 4. This causes a pressure change and the damper effect set by the damper hole 15 is effective in preventing vibration of the valve body.

Furthermore, the same effect can be obtained by attaching the damper diaphragm 21 to the gas side of the diaphragm 5, and an embodiment will be explained with reference to FIG. A fluid inlet 1, an outlet 2, and a valve seat 3 are formed in the body 12, and a damper diaphragm 21 is attached thereto.A valve body 4 is fastened to the damper diaphragm 21, and faces the valve seat 3. The central upper part of the valve body 4 passes through the damper diaphragm 21 and comes into contact with the central abutting part 6 of the diaphragm 5 to form a governor part. Damper diaphragm 2
1 is provided facing the diaphragm 5 and constitutes a damper chamber B. Its effective diameter is smaller than that of the diaphragm 5. The damper chamber is
The damper hole 15 communicates with the gas side.

The electric drive unit has the same configuration and function as the conventional example, so a description thereof will be omitted.

Here, the damper chamber B has a damper effect that suppresses rapid movement of the valve. In other words, when the valve body 4 moves rapidly, that is, when the damper diaphragm 21 and the diaphragm 5 try to move rapidly, there is a difference in the effective diameters of the diaphragm 5 and the damper diaphragm 21, so the outlet pressure P ₂ in the damper chamber increases. A positive or negative pressure is generated. The pressure always acts on the diaphragm 5 in the opposite direction of its movement. This is effective in preventing vibration of the valve.

As described above, according to the present invention, it is possible to realize a pressure control valve which has a simple structure, has extremely stable operation, and whose outlet pressure can be arbitrarily changed by an external electric signal.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional example, and FIG. 2 is a conventional example provided with a damper chamber similar to a gas governor. Third
The figure is a sectional view of a pressure control valve in one embodiment of the present invention. FIG. 4 is a sectional view of another embodiment of the present invention. 4... Valve body, 5... Diaphragm, 15... Damper hole, 21... Damper diaphragm, Lo...
...damper room.

Claims (1)

[Claims] 1. The damper chamber includes a gas governor section and an electric drive section that increases or decreases the force acting on the valve body of the gas governor section in response to an electric signal, and a damper diaphragm having a different effective diameter is provided opposite to the diaphragm of the gas governor section. A pressure control valve comprising: a damper chamber communicated with either the atmosphere side or the gas side through a damper hole.