JPH03113182A - Solenoid valve - Google Patents

Abstract

PURPOSE:To suppress the vibration of a plunger by installing a vibrationproof spring which is brought into contact with both surfaces of the plunger end face and the cover of a solenoid housing when the stroke of the plunger is small, and which is separated from both surface when the stroke is large, between both the surfaces. CONSTITUTION:When a solenoid 35 is applied with electric current, magnetic force lines passing through a cover 36, plunger 31, solenoid housing 20 and an outer ring 25 are generated, and the force attracting the plunger 31 to a yoke 21a and an outer ring 25 is generated, and the plunger 31 and a spool 42 advances rightward, overwhelming a spring 54, and a ball 28 rolls on a supporting rod 29 and the outer ring 25, and no sliding resistance is applied to the supporting rod 29 and the plunger 31. In this case, if the applied electric current to the solenoid 35 reduces, and the plunger 31 is returned by a pressure adjusting spring 54, a vibrationproof spring 60 is brought into contact with both the surfaces of the plunger 31 and a cover 36, and an elastic cushion action is developed, and the amplitude of the plunger 31 reduces. Further, if the applied electric current is large, the spring 60 is separated from the cover 36.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is an electromagnetic tea ceremony device in which a plunger is actuated by magnetic attraction force, and the spool is moved axially.
This invention relates to a solenoid valve that opens and closes a fluid passage.

<Prior Art> As shown in FIG. 3, such a conventional solenoid valve includes a first solenoid housing 1 made of a magnetic material and a non-magnetic link 2.
A continuous sliding hole 4 is formed inside a second solenoid housing 3 made of a magnetic material, a plunger 5 made of a magnetic material is slidably inserted into this sliding hole, and a current is applied to the solenoid 6. A line of magnetic force is formed that passes through the cover 7, the second solenoid housing 3, the plunger, and the first solenoid housing 1, and the plunger 5 is connected to the yoke 8 formed at one end of the first solenoid housing 1 or the first solenoid housing 1. A shaft 10 made of a non-magnetic material is connected to the plunger 5 and inserted through the center of the stopper member 9. an electromagnetic actuating device in which a flange portion 11 abutting the plunger 5 is formed, and the flange portion 11 limits the operating range of the plunger 5 so as not to use a range where linear characteristics cannot be obtained; and the shaft of this electromagnetic actuating device. A plurality of fluid passages 13 provided in the spool housing 12 are pressed into contact with the spool housing 12 by a spring 15 and are moved axially against the spring 15 by the operation of the plunger 5.
This configuration includes a spool 14 that opens and closes.

<Problems to be Solved by the Invention> The electromagnetic actuating device in the solenoid valve described above has a large frictional resistance because the sliding hole 4 and the plunger 5 come into sliding contact.
However, there is a problem with large steresis. If the plunger 5 is guided by a bearing in order to reduce this frictional resistance, the above problem will be solved, but as the supply pressure increases, the change in output pressure will increase with respect to the change in spool stroke, and the pressure regulation sensitivity will increase. . When the change in output pressure with respect to the change in the sprue stroke becomes large, the damping effect of the spool pulp becomes small, and as a result, when the supply pressure becomes high, vibration of the plunger is likely to occur, and the pressure amplitude of the output fluid becomes large. There is.

Means for Solving the Problems> The present invention provides a solenoid valve in which the above-mentioned problems are solved.The present invention has a structure in which a solenoid is disposed on the outer periphery of a solenoid housing made of a magnetic material, and a solenoid is disposed inside the solenoid housing. A fitting hole is formed in the fitting hole, and a plunger made of a magnetic material is supported in this fitting hole via a direct-acting ball bearing, and the plunger is brought into contact with the plunger by the pressing force of a pressure regulating spring and is axially moved by the stroke of the plunger. and a spool that opens and closes the fluid passage with a spool, and the plunger end face and the cover of the solenoid housing are in contact with each other between the two faces when the stroke of the plunger is small, and are separated between the two faces when the stroke of the plunger is large. It is equipped with an anti-vibration spring.

With the above configuration, the frictional resistance of the plunger is reduced by rolling when the plunger moves, and when the applied flow is small and the spool stroke is small, the plunger has a cushioning effect due to the elastic action of the anti-vibration spring. This suppresses the vibration of the plunger and reduces the amplitude of the pressure of the output fluid.

<Example> Hereinafter, an example of the present invention will be described based on the drawings. A solenoid housing 20 is made of a magnetic material, and the solenoid housing 20 includes a cylindrical portion 21 and a flange portion 22. A yoke 21a is formed at one end of the cylindrical portion 21. A fitting hole 23 is formed penetrating inside the solenoid housing 20, and a stepped portion 24 is formed in the middle of the fitting hole 23.
is formed. A cylindrical outer ring 25 made of a magnetic material is fitted up to a position where it abuts on this stepped portion 24.
A cylindrical retainer 26 made of a non-magnetic material is fitted into the retainer 5 . One end of the retainer 26 protrudes from the outer ring 25 for a predetermined wind, and the other end of the retainer 26 is formed with a flange portion 26a bent outward, and the flange portion 26a holds balls at positions spaced apart from each other in the longitudinal direction of the retainer 26. A window 27 is formed, and a ball 2 is inserted into each ball holding window 27.
It contains 8. The ball holding window 27 is formed to be larger in diameter than the ball 28 so that the ball 28 does not come into contact with it.

These outer ring 25, retainer 26, and balls 28 constitute a direct-acting ball bearing.

This ball bearing allows the support rod 2 made of non-magnetic material to
9 is guided and supported, and a knurling eye 30 is provided at one end of the support rod 29.
is molded. A plunger 31 made of a magnetic material is press-fitted into this knurling 30.

A solenoid 35 is arranged around the outer periphery of the solenoid housing 20, and the solenoid 35 is covered with a cover 36 made of a magnetic material. A recessed hole 38 is formed in the cover 36 coaxially with the fitting hole 23 of the solenoid housing 20, and the plunger 31 is loosely fitted into this recessed hole 38.

40 is a spool housing made of a non-magnetic material, which is attached to the cover 3 while in contact with the solenoid housing 20.
6 is connected to the solenoid housing 20 by caulking one end thereof. Through this connection, the outer ring 26 is sandwiched between the stepped portion 24 and the spool housing 40, and the outer ring 26
6 is held in place. Spool housing 40
A sliding hole 41 is formed coaxially with the fitting hole 23, and a spool 42 is slidably inserted into the sliding hole 41.

The spool housing 40 has a solenoid housing 20
In this order, a first tank passage 43, a feedback passage 44, in which the flash tank outside the cover 36 communicates with the sliding hole 41, and a supply passage 45, in which the flash tank pump communicates with the sliding hole 41. , a line passage 46 through which the Sengoku actuator and the sliding hole 41 communicate, and the Sengaku tank and the sliding hole 4.
A second tank passage 47 communicating with the tank 1 is formed.

The spool 42 has each of the passages 43, 44, 45, 46.
Land portions for controlling the opening and closing of 47 are formed at a plurality of positions at intervals.

A cap 53 is screwed into the sliding hole 41,
A pressure regulating spring 54 is interposed between the cap 53 and the tip of the spool 42 to press and bias the spool 42 in the direction of contacting the support rod 29.

Further, the end surface of the plunger 31 and the surface of the recessed hole 38 of the cover 36 are prevented from coming into contact with each other when the stroke of the plunger 31 is small, and separating between the two surfaces when the stroke of the plunger 31 is large. A swing spring 60 is installed. The vibration isolating spring 60 is attached to a counterbore provided in the end face of the plunger 31 or is held on the side of the recessed hole 38.

Next, the operation will be explained based on the above-described configuration. When a current is applied to the solenoid 35, lines of magnetic force are generated that pass through the cover 36, the plunger 31, the solenoid housing 20, and the outer ring 25, and a force that tends to attract the plunger 31 to the yoke 21a and the outer ring 25 is generated. Due to this suction force, the plunger 31 and spool 4 in FIG.
2 overcomes the spring 54 and moves to the right. By this movement to the right, the ball 28 rolls on the support rod 29 and the outer ring 25, so that no sliding resistance is applied to the support rod 29 and the plunger 31 due to sliding. .45.46.47 Control the degree of opening of the communication passages between each other to be large or small. This plunger 31
The movement of the plunger 31 to the right is restricted by contact with the retainer 26, which restricts the operation of the plunger 31 near the outer ring where linear characteristics cannot be obtained.

In the above operation, the current value applied to the solenoid 35 is
When the pressure decreases and the plunger 31 is returned by the pressure regulating spring 54, that is, when the pressure regulating value changes from small to large, the anti-vibration □ spring 60 comes into contact with both sides of the plunger 31 and the cover 36 and acts as an elastic cushion. As the amplitude of the plunger 31 becomes smaller, the pressure amplitude of the fluid becomes smaller.

Further, when the applied current value I is large and the plunger stroke is large (when the pressure adjustment value is small), the vibration isolation spring 60 is separated from the cover 36, and no spring force is applied between the cover 36 and the plunger 31.

The above action is shown in a curve graph as shown in FIG. 2, where In is the current value at which the anti-vibration spring 60 and the plunger 31 come into contact, and the A curve shows the case where only the pressure regulating spring 54 acts on the plunger 31. 8 curve, the plunger 31 is the pressure regulating spring 54
The case is shown in which the current is affected by the action of two composite springs on both sides of the anti-vibration spring 60, and in this way, where the current value is small and the pressure regulation value P is high, it changes on the 8 curve, and the spring constant becomes large. The change in the pressure regulation value P with respect to the change in the current value becomes smaller,
The vibration of the plunger 31 is suppressed. Further, where the current fMI is large and the pressure regulation value P is low, it changes on the A curve, the spring constant becomes small, and a large return force can be taken.

<Effects of the Invention> As described above, in the present invention, a solenoid is disposed on the outer periphery of a solenoid housing made of a magnetic material, a fitting hole is formed inside the solenoid housing, and a plunger made of a magnetic material is inserted into the fitting hole. is supported via a direct-acting ball bearing, and when the stroke of the plunger is small, the end face of the plunger and the cover of the solenoid housing come into contact between the two faces, and when the stroke of the plunger is large, there is contact between the two faces. Since the vibration isolating springs are installed at a distance, the plunger operates smoothly, and the vibration of the plunger is reduced in areas where the plunger stroke is small and the pressure regulation value is high. In particular, compared to the case where the plunger is pushed from both sides by a spring over the entire stroke, a large return force can be obtained, so hysteresis is small, foreign objects can be easily removed, and foreign object resistance is improved.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the present invention, FIG. 2 is a control value characteristic diagram of the present invention, and FIG. 3 is a sectional view of a conventional device. 20... Solenoid housing, 23... Fitting hole,
25... Outer ring, 26... Retainer, 28... Ball, 31... Plunger, 35... Solenoid, 3
6... Cover, 42... Spool, 54... Pressure adjustment spring, 60... Vibration proof spring.

Claims (1)

[Claims] A solenoid is disposed on the outer periphery of a solenoid housing made of a magnetic material, and a fitting hole is formed inside the solenoid housing, and a plunger made of a magnetic material is supported in this fitting hole via a direct acting ball bearing. a spool that comes into contact with the plunger by the pressing force of a pressure regulating spring and moves axially with the stroke of the plunger to open and close the fluid passage; 1. A solenoid valve characterized in that a vibration-proofing spring is installed which abuts between both surfaces and separates between the two surfaces when the stroke of the plunger is large.