JPS6224087A - Solenoid control valve - Google Patents

Abstract

PURPOSE:To increase the flow of a controlled fluid without increasing the spool diameter by feeding the controlled fluid to both the large-diameter hole of a valve main body and a communicating hole formed on a spool. CONSTITUTION:At the communicating position, the fluid flowing in from an inlet port P1 is divided into the first stream passing between the first spool groove 32 and a sleeve land 17 via a large-diameter hole 16 to an outlet port P2 and the second stream passing between the second spool groove 34 and an inner hole 10a via a communicating hole 36 and a spool inner hole 35 to the outlet port P2. Both the first stream and second stream generate a flow force against the energizing force of a spring 42, thus the solenoid capacity can be made small as compared with the responsiveness of a spool 30.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnetic control valve using a spool, and particularly to an electromagnetic control valve that is normally open and becomes closed by energizing the solenoid.

[Prior art]

This type of electromagnetic control valve is designed so that the direction of the force (flow force) exerted on the spool by the controlled fluid matches the direction of the solenoid's suction force on the spool, and the response speed of the spool is relatively fast compared to the solenoid's capacity. There are some measures designed to improve For example, in the prior art shown in FIG. 4, when the solenoid is in an open state where no current is applied, fluid flows from the inlet port 2 of the valve body 1 through the notch 4 of the spool 3 to the lower surface of the notch 4, as shown in the figure. Since negative pressure is generated in the spool 3, a downward flow force acts on the spool 3, and this flow force moves the spool 3 downward against the spring 5 to close the electromagnetic control valve in the suction direction of a solenoid (not shown). , the response speed of the spool 1 can be improved compared to the capacity of the solenoid.

[Problems to be solved by the invention] In such conventional technology, increasing the diameter of the spool can be considered to increase the flow rate of the controlled fluid, but increasing the diameter of the spool leads to an increase in the size of the electromagnetic control valve. There is a problem. The present invention divides the fluid flowing in from the inlet port into upper and lower parts and controls them using one spool, and the direction of the flow force acting on the spool at the upper and lower parts is made to coincide with the suction direction of the solenoid. This is an attempt to obtain a large electromagnetic control valve.

[Means for solving problems]

To this end, the present invention provides an inner hole 10a, an inlet port P1 communicating with the inner hole, and an outlet port P2 communicating with the inlet port via the inner hole 10a, as shown in FIGS.
The valve body 10 has a valve body 10 which is slidably fitted in the inner circumferential surface of the inner hole 10a in the axial direction, and has both ports P1. A spool 30 that controls opening and closing of communication between P2 and both ports P
1. A spring 42 that urges the spool 30 in the axial direction toward a communication position that does not interfere with communication between the ports PL and P2, and an applied control current that forces the spool 30 against the spring 42 to In the electromagnetic control valve, the spool 30 has a spool inner hole 35 that opens at the end 37 of the spring 42 in the biasing direction, and a spool inner hole 35 that opens from the end 37 to the outer space. The first spool lands 31. First spool groove 32. The second spool land 33 and the second spool groove 34, and the first and second spool grooves formed between the first spool land 31 and the first spool groove 32 and between the second spool land 33 and the second spool groove 34, respectively. 2 tapers 32a, 34a, and a communication hole 36 that communicates the spool inner hole 35 and the second spool groove 34.
The valve body 10 has large-diameter holes 16., which are coaxially continuous with the inner hole 10a and arranged sequentially from one end corresponding to the end portion 37 of the spool 30. A sleeve land 17 and a sleeve groove 18 are formed, and the inlet port PL is opened to the sleeve groove 18, and in the communicating position, the sleeve land 17 is located in the first spool groove 32 and in the second spool land. 33 is located within the sleeve groove, and the large-mouth bow 1-PI is communicated with the outlet port P2 through the communication hole 36, the passage formed by the spool inner hole 35, and the large-diameter hole 16, and is in the closed position. In this case, the first spool land 31 is fitted into the sleeve land 17, and the second spool land 33 is fitted into the inner hole 10a to close communication between the inlet port P1 and the outlet port 1)2. This is a characteristic feature.

[Effect]

In the communicating position, as shown in FIG.
The fluid flowing in from the first spool groove 32 and the sleeve land 17 passes through the large diameter hole 16 toward the outlet port P2, and the second spool groove 34 and the inner hole 1
0a, the second flow passes through the communication hole 36 and the spool inner hole 35, and heads toward the outlet port P2. The first flow is at the first corner 1.6 of the sleeve brand 17 on the large diameter hole 16 side.
2 and the first tapered surface 32a, and the pressure is higher on the upstream side than on the downstream side. There is a difference in the axial component of the flow force acting on the opposing step portions (third tapered surface 32b), and the flow force exerted on the spool 30 by the first flow is directed against the spring 42. On the other hand, the second flow
Since the pressure changes around the aperture R2 formed between the second corner 18a and the second tapered surface 34a of the sleeve 1M18 example of a, the flow force is in the same direction as the direction of action of the spring 42, contrary to the above. is exerted on the spool 30, but after passing through the restriction R2, this second flow is reversed as shown in FIG. 1, and the direction of the flow along the axis is reversed. Therefore, regarding the second flow, pressure acts on the second tapered surface 34a of the restrictor R2 section, and a force in the direction of opening the spool 30 is generated, but the jet of fluid flows toward the communication hole 36 or the fourth tapered surface. 34b, a force is generated in the direction of closing the spool 30. Due to the action of these two forces, the flow force due to the second flow is also directed against the spring 42.

If a control current is applied to the solenoid 43, the spool 30
receives the action of both the suction force from the solenoid 43 and the flow force from the first and second flows, and is displaced toward the closed position against the biasing force of the spring 42.

〔Effect of the invention〕

In the electromagnetic control valve according to the present invention, the controlled fluid passes through both the large diameter hole formed in the valve body and the communication hole formed in the spool, and the opening and closing of the fluid is controlled by the spool, so that the diameter of the spool can be increased. Moreover, since both the first flow passing through the large diameter hole and the second flow passing through the communication hole generate a flow force that resists the biasing force of the spring, the spool The capacity of the solenoid can be made smaller compared to its responsiveness. Therefore, according to the present invention, a small electromagnetic control valve with a large flow rate can be obtained.

〔Example〕

The present invention will be described in detail below with reference to the accompanying drawings. Third
As shown in the figure, the valve body 10 includes a magnetic base 11, a non-magnetic sleeve 12 whose one end is fitted into a protrusion on the upper side of the base 11, and an intermediate plate on the inner peripheral surface of the sleeve 12. a spacer 14 made of a non-magnetic material, a stepped sleeve 13 made of a magnetic material fitted to the inner peripheral surface of the other end of the sleeve L2, and a base 1
A valve sleeve 15 made of a non-magnetic material is fitted coaxially with the sleeve 12 on the lower side of the valve sleeve 11.
2, 13, 14, and 15 are joined together by copper brazing or the like, and then one continuous inner hole 10a is formed. A magnetic yoke 40 with an adjustment screw 41 screwed into the center thereof is screwed and fixed to the stepped sleeve 13 coaxially with the inner hole 10a. The valve body 10 is attached by fitting a valve sleeve 15 into a fitting hole 51 formed in a housing 50 of a controlled device such as a transmission, and bolting or the like.

As shown in FIG. 3, a spool 30 made of a magnetic material is fitted into the inner hole 10a so as to be slidable in the axial direction. The spool 30 is urged downward through a spring 42, and normally the lower end 37 of the spool 30 is brought into contact with the upper surface of the end member 20 press-fitted into the lower end of the valve sleeve 15. There is.

A solenoid 43 wound around a non-magnetic bobbin 44 is provided on the outer periphery of the sleeve 12 and the stepped sleeve 13.
The valve body surrounding this solenoid 43 and its lower end is
A cover 45 that engages with the yoke 40 is provided and is fixed to the yoke 40 by a nand 46 that is threaded onto the adjustment screw 41.

As shown in FIGS. 1 and 2, on the inner periphery of the valve sleeve 15 of the valve body 10, large diameter holes 16. A sleeve land 17 and a sleeve groove 18, which form part of the inner hole 10a, are formed.

The inlet bow 1-PI is formed in the valve sleeve 15 so as to open into the sleeve groove 18, and the inlet bow 1-PI is formed in the valve sleeve 15 so as to open into the sleeve groove 18, and
0 is press-fitted and fixed into the large diameter hole 16, and an outlet port 1-P2 is formed in this end member 20, which communicates with the inlet port P1 via the inner hole 10a. A plurality of notches 2 are provided in the upper part of the end member 20 to communicate the large diameter hole 16 and the outlet port P2.
1 is provided. As shown in FIG.
0, the inlet and outlet ports PI, P2 are in communication with inlet and outlet passages 52 and 53 formed in the housing 50.

As shown in FIGS. 1 and 2, the spool 30 is coaxially formed with a spool inner hole 35 that opens at the end 37 that contacts the end member 20, and the spool 30 has a spool inner hole 35 formed coaxially with the spool 30 opening at the end 37 that contacts the end member 20. A first spool land 31° and a first spool groove 32 that can be fitted with the sleeve land 17. A second spool land 33 and a second spool groove 34 that can fit into the inner hole 10a are formed. First and third tapered surfaces 32a and 32b are formed between the first spool groove 32 and the spool lands 31.33 on both sides, and second and fourth tapered surfaces 34a are formed on both sides of the second spool groove 34.

34b is formed. Spool 30 has a second spool /j! A plurality of communication holes 36 are provided that communicate the spool 34 with the spool inner hole 35.

As shown in FIGS. 1 and 3, in the communicating position where the end 37 of the spool 30 biased by the spring 42 is in contact with the end member 20, the slide brand 17 is inserted into the first spool groove 32. The second spool land 33 is located within the sleeve groove 18, and the aperture R1 formed between the first corner 16a on the large diameter hole 16 side of the sleeve land 170 and the first tapered surface 32a is located within the sleeve groove 18. 18
The opening area is smaller than the diaphragm formed between the third corner 18b of the side and the third tapered surface 32b, and the second corner 18a of the three 1118 example of the inner hole 10a and the second tapered surface 34
The aperture R2 formed between the lands 17, 31, 33 and the groove 1 has the same opening area as the aperture R1.
8.32.34 dimensional relationships shall be determined. In addition to this, these dimensional relationships are as shown in Figure 2.
When the spool 30 is attracted by the yoke 40 excited by the solenoid 43 and is in the closed position farthest from the end member 20, the first spool land 31
The second spool land 33 is designed to fit into the sleeve land 17 and the second spool land 33 into the inner hole 10a. Note that the third and fourth tapered surfaces 32b and 34b may be simply a right-angled step.

Next, the operation of this embodiment will be explained. In the communicating position, as shown in FIG.
The fluid flowing through the PL is divided into a first flow passing through the restriction R1 and a second flow passing through the restriction R2. The first flow passes through the notch 21 on the upper part of the end member 20 from inside the large diameter hole 16, and the second flow passes through the sleeve inner hole 35 from the communication hole 36, and then the two flow together to form the outlet. Port P2
It flows out from the outflow passage 53 through.

Since the opening area of the first flow is the smallest near the throttle R1, the pressure is higher on the upstream side of the border around this area than on the downstream side. As a result, a large upstream pressure is applied to the entire surface of the third tapered surface 32b, whereas the first tapered surface 32b
Since a large upstream pressure is only applied to a portion of 2a, there is a difference in the axial component of the flow force acting on both tapered surfaces 32a and 32b, which causes a difference in the upward force, that is, on the spring 42. The direction is to resist.

On the other hand, since the second flow has the smallest opening area near the throttle R2, a pressure difference occurs around this area as a boundary. As a result, a partially large upstream pressure is applied to the second tapered surface 34a, whereas a small downstream pressure is applied to the entire fourth tapered surface 34b, so both tapered surfaces 34a
, 34b, there is a difference in the axial component of the flow force, which is subtracted downward, that is, in the same direction as the direction of action of the spring 42. However, after the second flow passes through the restrictor R2, the upward flow reverses to a downward direction, as shown in FIG. Therefore, the jet of fluid acts on the communication hole 36 or the fourth tapered surface 34b, and the spool 30
Force is generated in the direction of closing. Due to the action of this force and a force in the same direction as the acting direction of the spring 42, the flow force due to the second flow is also directed against the spring 42.

When a limiting tm current is applied to the solenoid 43, the excited yoke 40 does not exert an upward magnetic attraction force against the spring 42 on the spool 30. The spool 30 is acted upon by both this magnetic attraction force and the flow force caused by the first and second flows, and is displaced upward against the biasing force of the spring 42, reaching the closed position shown in FIG. . When moving from the open position to the closed position, the flow force acts to assist the magnetic attraction force by the solenoid 43, so the response speed of the spool 30 is short compared to the capacity of the solenoid 43.

In the closed position, the first spool land 31 fits into the sleeve land 17, and the second spool land fits into the inner hole tOa, connecting the inlet port l-Pl and the outlet port P.
The communication between the two is closed and at the same time the flow force disappears. When the control current to the solenoid 43 is released, the magnetic attraction force of the yoke 40 disappears, and the spool 30 returns to the communicating position shown in FIG. 1 by the biasing force of the spring 42. At this moment of return, flow force has not yet occurred, so there is no influence from flow force.

[Brief explanation of the drawing]

(Figs. 1 to 3 show an embodiment of the electromagnetic control valve according to the present invention. Fig. 1 is a sectional view of the main parts in the communicating position, Fig. 2 is a sectional view of the main parts in the closed position, and Fig. 3 is a sectional view of the main parts in the closed position. 3 is an overall cross-sectional view at a communicating position, and FIG. 4 is a cross-sectional view of essential parts of an example of the prior art.Description of symbols 10...Valve body, 10a...Inner hole, 16...
Large diameter hole, 17... Sleeve land, 18... Sleeve groove, 30... Spool, 31... First spool land, 32... First spool groove, 32a... Tapered surface, 33 ...Second spool land, 34...Second spool groove, 34a...Second tapered surface, 35...Spool inner hole, 36...Communication hole, 37...End portion, 42...
... Spring, Pl... Inlet port, P2... Outlet port.

Claims (1)

[Claims] a valve body having an inner hole, an inlet port communicating with the inner hole, and an outlet port communicating with the inlet port through the inner hole; a spool that controls opening and closing of communication between the ports; a spring that urges the spool in the axial direction toward a communication position that does not impede communication between the ports; In the electromagnetic control valve comprising a solenoid that displaces the spool to a closed position that closes communication between the two ports, the spool has a spool inner hole that opens at an end in the biasing direction of the spring;
A first spool land, a first spool groove, a second spool land, and a second spool land, which are sequentially formed along the outer circumference from the end.
a spool groove; first and second tapered surfaces formed between the first spool land and the first spool groove; and between the second spool land and the second spool groove; and the spool inner hole and the second spool groove. The valve body has a communication hole that communicates the grooves, and a large diameter hole, a sleeve land, and a sleeve groove are formed in the valve body in order from one end corresponding to the end of the spool, coaxially and continuous with the inner hole. The inlet port is open to the sleeve groove, and in the communicating position, the sleeve land is located in the first spool groove, the second spool land is located in the sleeve groove, and the inlet port is opened in the communication hole. and a passage formed by the spool inner hole and the large diameter hole to communicate with the outlet port, and in the closed position, the first spool land fits into the sleeve land and the second spool land connects to the inner hole. An electromagnetic control valve, characterized in that the valve is fitted into the valve to close communication between the inlet port and the outlet port.