JPH032073Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention consists of a plunger that moves by electromagnetic attraction, a valve body that abuts against the plunger and moves together, and a valve body that is at least always in the valve closing direction. The present invention relates to a flow control valve that is equipped with a biasing return spring and that controls the flow rate of fluid in proportion to the amount of input electricity.

[Conventional technology]

As a conventional flow control valve of this type, the one shown in FIG.
-112467). That is, in FIG. 8, the valve body 1 is provided with one branch passage 12 and the other branch passage 13 communicating with the fluid inlet 5, and a fluid outlet provided in each of these branch passages 12 and 13 with a partition wall in between. Passage 16 communicates with fluid outlet 6. Valve body 1 has spring receiver 2
is screwed on.

The wall portion between one branch passage 12 and the fluid outlet passage 16 and the other branch passage 13 and the fluid outlet passage 16
A circular hole-shaped valve seat is provided in the wall portion between the two valve seats, and a first valve 7a controls the opening area of each valve by being close to or apart from these two valve seats.
and a second valve 7b coupled thereto. The rear end (left end in the figure) of the first valve 7a is slidably fitted into a bearing provided inside a core 9a, which will be described later, and is connected to a non-magnetic shaft integrally connected to the plunger 8. The tip of the second valve 7b (the right end in the figure) is slidably fitted into the guide hole provided in the spring receiver 2. . A return spring 4 is compressed between the second valve 7b and the spring receiver 2.

Next, the electromagnetic drive means is a plunger 8 made of magnetic material.
A coil 9 arranged to surround the plunger 8, a magnetic core 9a fixed inside the coil 9, and a magnetic cover 10a integrally or integrally combined with the core 9a and extending outward. , a magnetic plate 10 connected to the cover 10a,
The spring 11 is compressed between the plate 10 and the plunger 8, and includes a spring 11 having a smaller spring constant than the return spring 4.

When the coil 9 is energized, the plunger 8 is magnetically attracted to the core 9a side according to the electrical input, so that the first valve 7a and the second valve 7 are
b moves against the urging force of the spring 4 to open the orifice and control the flow rate of fluid flowing from the branch passages 12 and 13 to the fluid outlet passage 16.

[Problem that the invention attempts to solve]

In the case of the conventional proportional control valve as mentioned above,
Since the negative pressure generated by the pressure difference before and after the valve cancels out when the valve is opened, it can be expected to have an effect on the input/output characteristics, such as extremely minimizing the effect of suction negative pressure in automobiles. If the two valves do not start opening at the same time, the flow characteristics will be disrupted, so the distance between one orifice and the other orifice and the corresponding distance between one valve and the other valve should be made to match. Must be manufactured with precision,
There was a problem that processing time was required.

[Means for solving problems]

The present invention has been made with the aim of solving the above-mentioned problems and downsizing the electromagnetic drive means. Although the shape of the fluid outlet passages 16 adjacent to the branch passages with a partition wall in between remains the same as before, 1
Use only one valve and change the shape of the valve to
The shape is such that the dynamic pressure caused by the flow of fluid when the valve is opened can be effectively utilized, thereby reducing the size of the electromagnetic drive means.

[Example of idea]

The present invention will be explained in detail below based on the embodiment shown in FIGS. 1 to 7. The same parts between the structure of this embodiment and the structure shown in the conventional example will be designated by the reference numerals cited in the conventional example. The explanation of the same structural parts will be omitted.

Embodiment In FIGS. 1 to 5, in the valve body 1 in this embodiment, one branch passage 12 and the other branch passage 13 branched from the fluid inlet 5 are disposed facing each other. One fluid outlet passage 16 is provided between the other branch passage 13 and one wall 14 and the other wall 15, and one wall 14 has a guide hole 1 in which the valve body 7 can slide.
7 is provided, and the other wall 15 is provided with a control port 18 for forming an orifice.

The valve body 7 includes a cylindrical guide portion 7a and a flow rate control portion A following the cylindrical guide portion 7a. The flow rate control unit A in this embodiment includes an inflow groove having an inflow surface 19 having a predetermined inflow angle β and a predetermined outflow angle α.
and an inflow groove having an outflow surface 20 having a predetermined R
It is formed in the shape of concave curved grooves connected by curved surfaces. A plurality of concave curved groove-shaped portions are usually formed on the outer circumferential surface of the valve body in a line symmetrical manner with respect to the valve axis.

A rear small diameter part 21 is connected to one end (left end in the figure) of the valve body 7, and a front small diameter part 22 having the same diameter as the rear small diameter part 21 is connected to the other end (right end in the figure).
is connected. The end of the rear small diameter portion 21 is in contact with the small diameter portion at the tip of the plunger 8, and the front small diameter portion 22 is loosely fitted into a guide hole provided in a spring receiver 2 screwed onto the valve body 1. 4 is a return spring compressed between the valve body 7 and the spring receiver 2; 11 is the plunger 8 and the plate 1;
0 and whose spring constant is smaller than that of the return spring 4. One end surface 7 of the valve body 7 facing one branch passage 12
The valve body 7 is provided with a communication passage 25 that communicates between the valve body 7 and the other end face 7 c of the valve body 7 facing the other branch passage 13 .

The operation of this embodiment having the above structure will be explained with reference to FIGS. 1 to 5. When the coil is not energized, the valve body 7 is at rest at a position where the biasing forces of the return spring 4 and the small spring 11 are balanced as shown in FIG. It's blocked. Also, at this time, one end surface 7 of the valve body 7
The same static pressures p ₁ and p ₂ act on b and the other end surface 7c, respectively. When the coil 9 is energized in this state, the plunger 8 and the valve body 7 are moved to the right in the figure against the combined biasing force of the return spring 4 and the small spring 11 due to the magnetic attraction force corresponding to the input electricity amount, for example, the duty ratio. Move to. Then, the inflow surface 19 of the valve body 7 communicates with the branch passage 13, and the fluid in the branch passage 13 flows into the inflow surface 19, so that p ₁ > p ₂ tends to be satisfied.
In this embodiment, since the communication path 25 is provided, p ₁ >p ₂ is never satisfied, and p ₁ =p ₂ is always satisfied.

Next, an axial thrust F ₁ is generated in the valve body 7 due to the dynamic pressure of the fluid flowing into the inflow surface 19 at the inflow angle β in the flow rate control section A. Its value is as shown in the following formula.

F ₁ = ρ・A・V ² (1−cosβ) … where ρ: fluid density A: orifice opening area V: inflow velocity The fluid that flows in at the inflow angle β passes through the R curved surface,
The water changes direction, becomes an outflow angle α, and flows along the outflow groove 20. Due to the dynamic pressure of this outflowing fluid, a thrust force F ₂ is generated in the valve body 7 in a direction opposite to the thrust force F ₁ in the axial direction. This value is as shown in the following equation.

F ₂ =ρ・A・V ² (1−cosα)... In the equation, if α<β, then F ₁ >F ₂ and |F ₁ −F ₂ | becomes a force that assists the electromagnetic attraction force. A graph in which this force is plotted on the vertical axis and the stroke of the valve body 7 is plotted on the horizontal axis is shown in FIG.

Figure 4 shows the stroke of the valve body 7 on the horizontal axis.
It is a graph where the vertical axis is the electromagnetic attraction force for each current application rate. A broken line A indicates the force that urges the valve body 7 in the closing direction by the return spring 4,
A broken line B indicates the force of the small spring 11 urging the valve body 7 in the opening direction, and a line obtained by combining these broken lines A and B is shown as a solid line S. In other words, unless there is a magnetic attraction force that exceeds the force shown by the solid line S, the valve body 7 cannot be moved in the valve opening direction.

For example, in Fig. 4, at a stroke of 4 m/m, in the conventional case, the duty ratio would have to be 100% to overcome the spring force (straight line S), whereas in this embodiment, as shown in Fig. 5, about
Since 50gr of force is added to the magnetic attraction force, it can overcome the spring force (straight line S) with a duty ratio of 80%. In other words, according to the present invention, the electromagnetic drive body can be made smaller for the same spring force.

Note that the small spring 11 in this embodiment
is provided mainly to prevent the end of the plunger from hitting the plate 10 and making abnormal noise when the plunger 8 returns. Needless to say, it can also be applied.

Embodiment FIGS. 6 and 7 are partially enlarged sectional views of a second embodiment of the present invention, with FIG. 6 showing the valve closed and FIG. 7 showing the valve open.

This embodiment can be considered to be a case in which an infinite number of inflow surfaces 19 and outflow surfaces 20 in FIGS. 1 to 3 are provided along the circumference. That is, the valve body 7 forms an inflow conical surface 23 having an inflow angle β, an outflow conical surface 24 having an outflow angle α, and an R curved surface R connecting these two conical surfaces.

In this embodiment, a pipe-shaped shaft 26
The valve body 7 is inserted into the valve body 7 and is integrated into the valve body 7.
Since the shaft 26 is provided with holes 27 and 28, the branch passages 12 and 13 are always in communication through the communication passage 25, and as shown in FIG. 7, even when the valve is open, the static pressure p ₁ = p ₂ is maintained, and the static pressure balance of the valve body 7 is maintained. When the valve is opened, the fluid that flows in from the branch passage 13 along the inflow conical surface 23 changes direction at the R curved surface R portion and flows out into the fluid outlet passage 16 along the outflow conical surface 24. It is clear that there is an effect of assisting the valve suction force by the dynamic pressure as explained in .

[Summary of the idea]

As described above, the present invention includes a plunger 8 that moves by electromagnetic attraction, a valve body 7 that is provided in the valve body 1 and moves together with the plunger, and a valve body that at least always moves in the valve closing direction. In the flow control valve equipped with a biasing return spring 4, one branch passage 12 and the other branch passage 13 communicating with the fluid inlet 5 side are provided in the valve body 1, and between these two branch passages,
A fluid outlet passage 16 is provided which is separated by one wall 14 and the other wall 15, the one wall 14 is provided with a guide hole 17 for guiding the valve body 7 in its movement direction, and the other wall 14 is provided with a guide hole 17 for guiding the valve body 7 in the direction of movement thereof. The wall 15 is provided with a control port 18 that cooperates with a flow control section provided in the valve body 7, the flow control section having an inflow surface 19 or 23 having a predetermined inflow angle with respect to the axis of the valve body;
Outflow surface 20 or 2, which also has a predetermined outflow angle
4, and the R curved surface R that connects these inflow and outflow surfaces.
Further, the static pressure receiving area of the portion of the valve body 7 facing the one branch passage 12 and the static pressure receiving area of the portion facing the other branch passage 13 are set to be equal. ,
This flow control valve is characterized in that a communication passage 25 between the one branch passage and the other branch passage is provided in the valve body 7.

[Effect of idea]

Therefore, according to the present invention, the valve body 7 is constantly subjected to static pressures that cancel each other out to maintain static pressure balance, completely eliminating disturbances in flow characteristics due to unbalance, and furthermore, the inflow angle β , outflow angle α
By appropriately selecting , an appropriate thrust can be applied to the valve body 7, which has the effect of making it possible to downsize the electromagnetic driving means.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing the first embodiment of the present invention, Fig. 2 is an enlarged sectional view of the main part of Fig. 1 and shows the valve closed state, and Fig. 3 is similar to Fig. 2. An enlarged sectional view showing the valve open state, FIG. 4 is an explanatory graph of stroke versus electromagnetic attraction force, and FIG. 5 is an explanatory graph showing the force added to the electromagnetic attraction force by the valve of the present invention. FIG. 6 is an enlarged cross-sectional view of the main parts of the second embodiment of the present invention, showing the valve open state; FIG. 7 is an enlarged cross-sectional view of the main parts similar to FIG. 6, showing the valve open state; FIG. 8 is an explanatory diagram of a conventional example. 1...Valve body, 2...Spring holder, 3
...θ ring, 4...Return spring, 5...Fluid inlet, 6...Fluid outlet, 7...Valve body, 7
a... Guide portion, 7b... One end surface, 7c... Other end surface, 8... Plunger, 9... Coil, 1
0...Plate, 11...Spring, 12...
Branch passage, 13...branch passage, 14...one wall, 15...other wall, 16...fluid outlet passage,
17... Guide hole, 18... Control port, 19... Inflow surface, 20... Outflow surface, 21... Rear small diameter portion, 22
...Front small diameter section, 23...Inflow conical surface, 24...
Outflow conical surface, 25... communicating path, 26... shaft, 27... hole, 28... hole.

Claims (1)

[Scope of utility model registration request] A plunger 8 that moves by electromagnetic attraction, a valve body 7 provided in the valve body 1 that abuts against the plunger and moves together with the plunger, and a return spring 4 that at least always biases the valve body in the valve closing direction. In the flow control valve, one branch passage 12 and the other branch passage 13 communicating with the fluid inlet 5 side are provided in the valve body 1, and one wall 14 and the other wall are provided between these two branch passages. A fluid outlet passage 16 is provided, which is separated by a fluid outlet passage 16, in which one wall 14 is provided with a guide hole 17 for guiding the valve body 7 in the direction of its movement; A control port 18 is provided which cooperates with a flow control section provided at the valve body, and the flow control section has an inflow surface 19 or 23 having a predetermined inflow angle with respect to the axis of the valve body, and an outflow surface 20 which also has a predetermined outflow angle. or 24, and a curved surface R connecting these inflow and outflow surfaces, and a static pressure receiving area of the portion of the valve body 7 facing the one branch passage 12, and the other branch passage 13.
The flow control valve is characterized in that the static pressure receiving area of the portion facing the flow control valve is set to be equal, and a communication passage 25 between the one branch passage and the other branch passage is provided in the valve body 7. .