JPS61286679A - Solenoid-controlled valve - Google Patents

Abstract

PURPOSE:To reduce the number of machining processes, by slidingly guiding a control spool with a guide shaft alone and supporting it without making it contact with each inner hole of a valve body and a sleeve. CONSTITUTION:Each inside of a body inner hole 10a and a sleeve inner hole 11a, there is provided with a control spool 20 free of shaft movement over both these inner holes, and this spool is energized to ward a plug 14 by a spring 22 installed interposingly between the spring and a spring bearing 13. In addition, the control spool 20 is slidingly guided and supported by a guide shaft 21 via a through hole 20a formed along the center, and in contrast to this, a clearance is installed in a space between an outer circumferential surface of the control spool 20 and an inner circumferential surface of the body inner hole 10a, while a clearance between an inner circumferential surface of the sleeve inner hole 11a and the body inner hole's inner circumferential surface becomes larger than the former.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention changes the opening area of a passage between two ports in response to a control current applied to a solenoid, thereby controlling the flow rate of fluid flowing between them. Regarding electromagnetic control valves.

[Prior art]

For example, as shown in FIG. 3, this type of electromagnetic control valve has a valve body 1 made of a magnetic material and a sleeve 2 made of a non-magnetic material fixed thereto. A solenoid door is wound around the outer periphery of a yoke 6 which is supported by springs 9, 9a and is fixed to the sleeve 2 via a stepped sleeve 5 made of a magnetic material. The opening area of the passage between the first and second ports 8a, 8b is changed by the tip of the control spool 4, which is displaced in the axial direction against the springs 9, 9a in response to the control current applied to the solenoid 7. There is.

In the conventional product, the outer peripheral surface of the control spool 4 is slidably supported by the inner peripheral surface of the inner hole 3 formed from the valve body 1 to the sleeve 2 and further to the stepped sleeve 5. In order to smooth the movement of the control spool 4 and reduce variations in control characteristics, the inner hole 3 is
It is necessary to finish the inner circumference smooth. For this purpose, after copper brazing the four parts 1, 2, 2a and 5 including the guide member 2a (non-magnetic material) which forms part of the sleeve 2, the inner hole 3
The inner circumferential surface was finished to obtain a smooth guide surface.

[Problem that the invention seeks to solve]

However, in this conventional technique, in addition to machining each part, brazing requires a process and a guide surface finishing process, which increases the number of machining steps and increases costs. The present invention solves the above problem by providing a guide shaft in the center of the control spool, thereby eliminating the need for guidance by the outer periphery of the control spool.

[Means for solving problems]

For this purpose, the electromagnetic control valve according to the present invention has two types of bows 1-30, as shown in FIGS. 1 and 2. 31 and a main body inner hole 10a through which both ports communicate with each other, and a sleeve inner hole 1 having one end fixed to the valve body and coaxially continuous with the main body inner hole 10a.
1a, and both inner holes 10 can be axially movable over both the main body inner hole 10a and the sleeve inner hole 11a.
a.

a control spool 20 that is supported within the control spool 11a and changes the opening area of the passage between the two bows 30 and 31 according to its axial displacement; a spring 22 that biases the control spool in one direction; The control spool 20 is connected to the spring 22 by a coke 12 coaxially fixed to the other end of the sleeve 11 and an attractive force generated in the yoke 12 in response to a control current wound around the outer periphery of the yoke and applied. In the electromagnetic control valve comprising a solenoid 25 that is displaced against the pressure, the plug 14 is fixed coaxially with the body inner hole 10a on the opposite side of the valve body 10 to the sleeve 11, the hundred-yen hole 10a, The control spool 20 is provided with a guide shaft 21 that coaxially passes through the inside of the lla with a considerable distance between it and the inner peripheral surface thereof, and has both ends supported by the yoke 12 and the plug 14. The hole 20a is slidably fitted into the guide shaft 21 to be guided and supported, and the outer circumferential surface and both inner holes 10a
, lla are characterized in that a gap is provided between them and the inner peripheral surfaces of lla.

[Effect]

The control spool 20 is displaced in the axial direction against the spring 22 by the attractive force generated in the yoke 12 in response to the control current applied to the solenoid 25, and the control spool 20 is displaced in the axial direction against the spring 22.
The opening area of the passage between the two is changed. During this displacement, the control spool 20 is slidably guided and supported only by the guide shaft 21.

〔Effect of the invention〕

As described above, according to the present invention, the control spool is slidably guided and supported only by the guide shaft and does not come into contact with the inner holes of the valve body and sleeve, so that the control spool is slidably guided and supported only by the guide shaft and does not come into contact with the inner holes of the valve body and sleeve. There is no need to process the inner peripheral surface into a continuous, smooth guide surface. Therefore, there is no need for the brazing process between parts, which was previously required, and for finishing the guide surfaces after brazing, so the number of processing steps can be reduced compared to the past, and manufacturing costs can be reduced. can be done.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 and 2. As shown in FIG. 1, a valve body 1 made of a magnetic material
A main body hole 10a is formed through the main body hole 10a, and a cylindrical portion 10b and a protruding portion 10c are integrally formed coaxially with the main body hole 10a and protruding from both sides. A plug 14 made of a non-magnetic material that supports a guide shaft 21, which will be described later, is press-fitted into the tip of the protrusion 10C, and a plurality of first ports 30 that open directly into the body internal hole 10a are provided on the peripheral wall of the protrusion 1゛Oc. In addition, the inward flange 14a of the plug 14 has a small diameter cylindrical portion 1.
A plurality of second holes communicate with the main body internal hole 10a through the inside of the main body 4b.
A port 31 (see FIG. 2) is provided. The valve body 10 is attached by fitting the protrusion 10c into a fitting hole 16a formed in the mounting base 16 and bolting or the like, and the first port 30 and the second port 31 are each formed in the mounting base 16. The passage 16b communicates with the fitting hole 16a. The mounting base 16 is, for example, a housing of a controlled device such as a transmission.

One end of a sleeve 11 made of a non-magnetic material is press-fitted liquid-tightly into the outer periphery of the cylindrical portion 10b of the valve body 10 via an O-ring, and the sleeve inner hole 11a on the inner periphery is press-fitted into the main body inner hole 10a.
A cylindrical yoke 12 made of a magnetic material is fluid-tightly press-fitted into the other end of the sleeve 11 via an O-ring. A cylindrical spring receiver 13 is liquid-tightly and slidably fitted into the through hole at the center of the yoke 12 via an O-ring, and a guide shaft 21 made of a non-magnetic material is fitted into the through hole at the center of the spring receiver 13. The tip portion is fitted liquid-tightly via an O-ring. The proximal end of the guide shaft 21 on which the annular protrusion 21a for preventing removal is formed is the inward flange 14a of the plug 14 press-fitted into the protrusion 10c of the valve body 10 as described above.
is fitted in the center of the In this way, both ends of the guide shaft 21 are fitted into the yoke 12 and the plug 14, and the guide shaft 21 is inserted into both inner holes 10a.
, 11a. The guide shaft 21 is assumed to have a relatively small diameter, and a considerable distance is provided between the inner holes 10a and lla. The threaded portion 21b at the tip of the guide shaft 21 passes through the center of the cover 17 made of a magnetic material.
The plug 14.b is engaged with the washer 24 and nut 23 provided at the annular projection 21a to prevent it from coming off. Valve body 10. Sleeve 11. The yoke 12 and the cover 17 are fastened to each other. In this embodiment, the spring receiver 13 is fitted with the threaded portion 21b so that its position in the longitudinal direction relative to the guide shaft 21 can be adjusted, and the tip of the guide shaft 21 is supported by the yoke 12 via the spring receiver 13. ,
The spring receiver 13 may be formed integrally with the yoke 12.

As shown in FIG. 1, the main body inner hole 10a and the sleeve inner hole 11
A control spool 20 is provided inside the inner hole 10a and 10a so as to be able to move axially, and this control spool 20 is urged toward the plug 14 by a spring 22 interposed between the control spool 20 and the spring receiver 13. 1, and is normally brought into contact with a plug 14 as shown in FIG. control spool 20
is slidably guided and supported by the guide shaft 21 through a through hole 20a formed along its center, and there is a gap ( For example, the gap between the sleeve inner hole 11a and the inner circumferential surface of the sleeve inner hole 11a is larger than this. A cylindrical portion 20b having a plurality of slits 20C around the periphery is formed at the end of the control spool 20 on the plug 14 side, and the inner peripheral surface of this cylindrical portion 20b is connected to the small diameter portion 14 of the plug 14.
It is slidably fitted onto the outer peripheral surface of b. As shown in FIG. 1 (when the control spool 20 is in contact with the plug 14, the slit 20c is closed by the small diameter cylindrical portion 14b, cutting off communication between the first port 30 and the second port 31, When the control spool 20 moves against the spring 22, the slit 20c opens in accordance with its axial displacement.
The opening area of the passage between both ports 30, 31 is increased.

A solenoid 25 wound around a non-magnetic bobbin 26 is provided on the outer periphery of the sleeve 11 and yoke 12, and the above-mentioned cover 17 is attached to surround the solenoid 25.

When no control current is applied to the solenoid 25, as shown in FIG. 1, the control spool 20 is brought into contact with the plug 14 by the spring 22, and communication between the first and second bows 30 and 31 is closed. ing. Solenoid 25
When a control current is applied to yoke 1, the yoke 1
Due to the magnetic attraction force generated in the control spool 20, the control spool 20, which is slidably supported by the guide shaft 21, is attracted and displaced in the axial direction against the spring 22. ) Increase the opening area of the passage between 30 and 31. In the axially displaced state, the end of the control spool 20 on the yoke 12 side enters into the recess 12a formed in the yoke 12.

[Brief explanation of drawings]

1 and 2 show an embodiment of the electromagnetic control valve according to the present invention, FIG. 1 is a longitudinal sectional view of the whole, and FIG. 2 is an I
[-II sectional view, FIG. 3 is a diagram corresponding to FIG. 1 of the conventional example. Explanation of symbols 10...Valve body, 10a...Body internal hole, 11.
...Sleeve, lla...Sleeve inner hole, 12...
Yoke, 14...Plug, 20...Control spool,
20a...Through hole, 21...Guide shaft, 22...Spring, 25...Solenoid, 30.31...
·port.

Claims (1)

[Claims] A valve body having two types of ports and forming an inner hole through which both ports communicate, and a sleeve having one end fixed to the valve body and having a sleeve inner hole coaxially continuous with the inner hole of the main body. a control spool that is supported in the inner bore of the main body and the inner bore of the sleeve so as to be able to move axially therein, and that changes the opening area of the passage between the two ports in accordance with the axial displacement of the control spool; a spring that biases the yoke in one direction, a yoke coaxially with the control spool and fixed to the other end of the sleeve, and an attractive force that is wound around the outer circumference of the yoke and generated on the yoke in response to a control current applied. an electromagnetic control valve comprising a solenoid for displacing the control spool against the spring with a guide shaft coaxially penetrating the inside with a considerable distance between the inner peripheral surface thereof and having both ends supported by the yoke and the plug;
The control spool is guided and supported by having a coaxially shaped through hole slidably fitted to the guide shaft, and a gap is provided between the outer circumferential surface of the control spool and the inner circumferential surfaces of the inner holes. An electromagnetic control valve characterized by: