JPS61241577A - Pressure proportional control valve - Google Patents

Abstract

PURPOSE:To obtain a pressure proportional control valve having the superior governor characteristic by limiting the magnetic gap, i.e., the relative relation between the position of a plunger and the shift quantity of a valve body within a prescribed range. CONSTITUTION:When a valve piece 6 reaches the max. shift quantity Xm in the state where a prescribed electric conduction quantity is provided onto a coil 10, the upper edge surface 13a of a plunger 13 and the lower edge surface 13b of the plunger 13 are not positioned below the upper edge surface 11a of a yoke 11 and the lower edge surface 11b of the yoke 11. Therefore, the electromagnetic-force characteristic in the rightward rising tendency is obtained with the shift of a valve body 6 without receiving the upward attraction force of the plunger 13. Therefore, when the shift position of the electromagnetic force and the variation quantity of the valve closing force by the spring constant of an elastic element 8 are allowed to accord, the governor setting pressure Fg can be kept constant, even if the valve body 6 shifts, and the superior governor characteristic can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides a fluid pressure proportional control valve that can be used to arbitrarily control the pressure on the fluid outlet side using electromagnetic force generated in response to an electric signal. Regarding.

BACKGROUND OF THE INVENTION FIG. 5 shows a conventional fluid pressure proportional control valve, in which numeral 1 denotes a governor section that controls pressure, and numeral 2 a drive section that generates electromagnetic force to control the governor section 1.

The governor section 1 includes a fluid inlet 3 and a fluid outlet 4, a valve seat 5 provided between the fluid port 3 and the fluid outlet 4, a valve body 6 provided opposite the valve seat 5, and a fluid inlet 3 supported by the valve body 6. Diaphragm 7 that operates in response to side pressure (hereinafter referred to as pyrotechnic) Pl
, an elastic element 8 that urges the valve body 6 to close, and a nut stopper 9 that regulates the amount of displacement of the valve body 6. The drive unit 2 includes a coil 10. Coil) A yoke 11 that surrounds the coil 1o, a sliding pipe 12 that penetrates through the center of the coil 1o, a plunger 13 that is installed inside the sliding pipe 12, and a mounting that forms a back pressure chamber for the diaphragm 7. It is composed of a stand 14.

In this configuration, when the carp) vlo is energized, an electromagnetic force Fm corresponding to the amount of energization acts on the valve body 6, the valve body 6 is displaced downward, and the fluid flows out to the fluid outlet 4 side, resulting in a secondary pressure of P2. occurs. In such a force relationship, since the effective pressure receiving areas of the valve body 6 and the diaphragm 7 are set equal, -
The pyrotechnic P1 is canceled and the secondary pressure P2 causes the valve body 6 to
The valve opening degree is determined by the balance between the force that lifts the valve upward and the electromagnetic force Fm. In other words, a secondary pressure P2 corresponding to the electromagnetic force Fm can be obtained and a well-known governor function can be obtained.

In this type of pressure proportional control valve, the plunger 13 is also displaced as the valve body 6 is displaced, so even when the same magnetomotive force is applied to the coil 10, the electromagnetic force changes as shown in FIG. This is because the displacement of the plunger 13 changes the magnetic gap (magnetic resistance). This electromagnetic force change affects the governor performance, and in order to improve the governor performance in this type of pressure proportional control valve, the displacement amount of the valve body 6
By approximately matching the amount of change in electromagnetic force when the valve changes from the closed state x□ to the maximum displacement amount Xm and the amount of change in the valve closing force due to the spring constant of the elastic element 8, the imbalance between the vertical forces is eliminated. It is possible to prevent changes in the governor setting force due to displacement of the valve body 6 (plunger 13), and to obtain good governor performance in which the secondary pressure P2 does not change with respect to fluctuations in the pyrotechnic force P1.

However, in the conventional example, good governor characteristics may not be obtained depending on how the magnetic gap is set. That is, when the plunger 13 is displaced from the valve closing point x□ to the maximum displacement amount Xm as shown in FIG.
When the lower end surface 13b of the plunger 13 is located below the lower end surface 11b of the yoke 11, the plunger 13
receives an upward electromagnetic attraction force. Therefore, the electromagnetic force Fm substantially acting on the valve body 6 has a characteristic that it decreases from the point of a predetermined valve body displacement amount xn, as shown in FIG. When using the drive unit 2 having such electromagnetic force characteristics, the governor setting force Fg (force obtained by subtracting 8 from the electromagnetic force Fm to the spring constant of the elastic element 8) is the force of the valve body 6 as shown in FIG. It shows a decreasing tendency with displacement. Therefore, looking at the governor characteristics, compared to the ideal characteristics shown in (8) in Figure 7,
The characteristic has an upward trend to the right as shown in (G) in the figure. In other words, when the pressure P1 is 0, the valve body 6 is at the maximum displacement Xm due to the electromagnetic force Fm, and is in contact with the stopper 9. Thereafter, when the pyrotechnic force P1 is increased, the valve element 6 starts to be displaced in the valve closing direction when the secondary pressure P2a corresponding to the governor setting force Fg in a in FIG. 6 is reached. Further - Pyrotechnical P
1 is increased, the valve body 6 is further displaced in the valve closing direction, but at this time, as the valve body 6 is displaced in the valve closing direction, the governor setting force Fy tends to increase. As a result, in Figure 7 @)
This results in an upward-sloping governor characteristic as shown in .

Similarly, the upper end surface 13a of the plunger 13 is connected to the yoke 1.
Similarly, good governor characteristics cannot be obtained in a state where the governor is located below the upper end surface 11a of No. 1.

Problems to be Solved by the Invention As described above, in the conventional example, good governor characteristics may not be obtained depending on the relationship between the position of the plunger and the amount of displacement of the valve body, that is, the setting of the magnetic gap.

6.12' Means for Solving the Problems The present invention has been made in view of the problems of the conventional example, and the present invention is made by adjusting the relative relationship between the magnetic gap, that is, the position of the plunger, and the amount of displacement of the valve body to a predetermined value. The purpose is to obtain good governor characteristics by limiting the amount within this range.

In order to achieve this objective, the pressure proportional control valve according to the present invention has a maximum displacement of the valve body of The gap is gb, and when the valve is closed, the plunger upper end face and plunger lower end face are located below the yoke upper end face and the yoke lower end face. Therefore, a desired governor setting force can be obtained without reducing the electromagnetic force with the displacement of the valve body (plunger), and good governor characteristics can be obtained.

7 Xm7 Example Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a pressure proportional control valve according to the invention, with a valve body 6
The maximum displacement amount, that is, the distance from the valve closed state to the stopper 9 contacting the stopper 9, is
The axial gap from a to the upper end surface 13a of the plunger 13 is ga, and the axial gap between the lower end surface 11b of the yoke 11 and the lower end surface 13b of the plunger 13 is 9, and in the valve closed state, Xm<9, Xm <' El b
It is configured to satisfy the following conditions. The other parts are the same as those of the conventional example shown in FIG. 3, so the same symbols are given and the explanation is omitted.

In the above configuration, the valve body 6 (
Even when the plunger 13) has reached the maximum displacement amount 11
It is never located below b. Therefore, the plunger 13 is not subjected to upward suction force, and as shown in FIG. 3, an electromagnetic force characteristic with an upward trend to the right can be obtained as the valve body 6 is displaced. As a result, the amount of change kl in the valve closing force due to the amount of change ΔFm in electromagnetic force and the spring constant of the elastic element 8 is found! If they match, it becomes possible to keep the governor setting force Fg constant even if the valve body 6 is displaced, and good governor characteristics as shown in (3) in FIG. 7 can be obtained.

As described above, according to this embodiment, the maximum displacement amount X of the valve body 6
Electromagnetic force characteristics that improve the governor characteristics can be obtained by a simple improvement in which the relative positions of the plunger 13 and the yoke 11 are set within predetermined conditions according to m. The magnetic gaps g8 and gb still have large dimensional variations due to dimensional variations of the component parts. In the conventional example, the variation in the magnetic gap directly affects the electromagnetic force characteristics, and the variation in the governor characteristics sometimes becomes large. However, according to this embodiment, By setting the values of the magnetic flux gaps g8 and gb to a large value of 9·Xm1 with a margin, it is possible to reduce the change in the amount of change in the electromagnetic force with respect to the displacement of the valve body 6, and it is possible to reduce the width of variation in the governor characteristics.

Effects of the Invention As described above, the pressure proportional control valve according to the present invention provides the following effects.

(1) The relative relationship between the maximum valve body displacement Xm, the axial gap ga from the yoke upper end face to the plunger upper end face, and the axial clearance Nb from the yoke lower end face to the plunger lower end face is expressed as xm < g, , xm < Suitable electromagnetic force characteristics can be obtained by simply improving the gb, stable and good governor characteristics can be obtained, and the yield can be improved.

(2) If the gaps g8 and gb are set with a margin for the maximum valve body displacement amount Xm, the range of variations in governor characteristics caused by variations in component dimensions can be reduced.

(3) Since the plunger is not used in an area where it receives upward force, electromagnetic force can be effectively used as valve opening force.

In other words, efficiency is high.

10 pages.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a pressure proportional control valve showing an embodiment of the present invention, Fig. 2 is a cross-sectional view of the main part thereof, and Fig. 3 is a relation diagram of the valve body displacement amount, electromagnetic force, and governor setting force. Fig. 4 is a sectional view of a conventional pressure proportional control valve, Fig. 5 is a sectional view of the same main part, and Fig. 6 is a sectional view of the same main part.
The figure shows the relationship between the displacement of the valve body, electromagnetic force, and governor setting force.
FIG. 7 is a characteristic diagram of the same governor. 1... Governor section, 2... Drive section, 5.
... Valve seat, 6... Valve body, 7...
Diaphragm, 8. River... Elastic element, 10...
Phil, 11・River...Yoke, 11a...Yoke upper end face, 11b...Yoke lower end face, 13
...Plunger, 13a...Plunger upper end surface, 13b...Plunger lower end surface. Name of agent: Patent attorney Toshio Nakao and 1 other person @
-I'm sorry for the music Figure 5 Figure 6 Figure 7 Mu! 4-Atmosphere 14r Tsuta Vr-)

Claims (1)

[Scope of Claims] A valve seat provided in a fluid passage, a valve body provided opposite to the valve seat, an elastic element that biases the valve body in a valve closing direction, and integrally formed with the valve body. The drive unit includes a governor section having a diaphragm, a coil, a yoke, and a plunger that moves along the central axis of the coil and applies an electromagnetic force to the valve body, and The amount is X_m
, the axial gap between the yoke upper end face and the plunger upper end face is g_a, the axial clearance between the yoke lower end face and the plunger lower end face is g_b, and the valve closed state is X_m<
A pressure proportional control valve that satisfies the following conditions: g_a, X_m<g_b.