JPH0330752B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a solenoid valve used in industrial machinery that utilizes fluid pressure and vacuum pressure.

[Prior Art] In a conventional solenoid valve, when the fixed core attracts the movable core by excitation of the excitation coil, or when the movable core is returned by a return spring, the movable core has a fixed part facing it. Since the impact caused by the collision causes large fatigue and wear of the movable core, the movable core is attracted in the radial direction and is unevenly distributed on the side where the attractive force acts strongly, and the outer peripheral wall of the movable core is attracted to the excitation coil. Since the movable iron core slides in contact with the inner surface of the cylinder made of non-magnetic material, the friction between the movable iron core and the cylinder causes large wear, and due to this fatigue and wear, the solenoid valve must be operated frequently. It was difficult to operate for a long time.

[Problems to be Solved by the Invention] Problems to be solved by the present invention are the collision between the end face of the movable core in the electromagnetic operation section and the fixed part opposing it, and the collision between the movable core and the surrounding fixed part. The object of the present invention is to prevent contact, reduce fatigue and wear caused by impact caused by collision of the movable core and contact with the outer peripheral fixed part, and increase the life of the solenoid valve.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides an inflow port and an outflow port for pressure fluid, a passageway that communicates both ports, a valve seat formed in the passageway, and a valve seat formed in the passageway. In a solenoid valve consisting of an electromagnetic operating section that operates to open and close, a part of the pressure fluid flowing through the electromagnetic valve is directed to either the end face of the movable iron core in the electromagnetic operating section or the fixed section opposing this, to the other opposing side. After the pressure fluid is ejected from the nozzle and collides with the opposing surface, the pressure fluid that flows through the gap between the movable core and the peripheral fixed part surrounding it is transferred to the end face of the movable core and the fixed part facing it. It is characterized by a means for alleviating the impact caused by collision with the outer fixed part and for holding the movable iron core in a non-contact state with the outer peripheral fixed part.

[Operation] When the movable core slides due to the suction force of the fixed core or the return spring, pressurized fluid is ejected from the spout hole provided on either the end face of the movable core or the fixed part facing this. The collision of the pressurized fluid with the opposing surface reduces the sliding speed of the movable core immediately before the collision with the fixed part, thereby reducing fatigue and wear of the material caused by the impact accompanying the collision of the movable core.

The pressure fluid that collides with the opposing surface flows through the gap between the outer peripheral wall of the movable core and the outer peripheral fixed part surrounding it, and the movable core is supported by the air bearing effect of this pressure fluid, and the movable core and the outer peripheral fixed part come into contact with each other. This prevents wear on the movable iron core.

[Embodiment] Figures 1 and 2 show a first embodiment of the present invention, in which a valve body 1 is provided with an inflow port 2 and an outflow port 3, and a valve body 1 is provided with an inflow port 2 and an outflow port 3 on a surface facing an electromagnetic operation section to be described later. A valve chamber 4 is recessed, the inflow port 2 is communicated with the valve chamber 4 by a passage 5 in the valve body 1, and the outflow port 3 is communicated with the valve chamber 4 by a passage 6 in the valve body 1. The valve seat 4a is connected to the valve seat 4a.

On the other hand, in the electromagnetic operation section, magnetic frames 13a and 13b having a U-shaped cross section and covering the outside of the bobbin 12 made of a non-magnetic material around which the excitation coil 11 is wound have holes provided at both ends of the magnetic frames 13a and 13b. The fixed core 15, which is inserted and fixed into the hole 14 of the bobbin 12 through the hole in one bent part, has a reduced diameter part formed near its suction end, and the reduced diameter part has an opening in the diametrical direction. A cross-shaped distribution hole 15a is provided therein, and a plurality of ejection holes 15b, .

A connecting ring 16 is fixed to the other end of the magnetic frames 13a, 13b, and by screwing the connecting ring 16 and the valve body 1 with a sealing member interposed, the magnetic frames 13a, 13b It is connected to the valve body 1. In addition, the magnetic frames 13a and 13b
In order not to reduce the insulation function of the exciting coil 11, its inner and outer peripheries are molded with synthetic resin.

Hole 14 of the bobbin 12, magnetic frames 13a, 13
A guide tube 18 made of a non-magnetic material is fitted into the inner surface of the hole provided in the bent portion of b and the hole of the connecting ring 16, and the guide tube 18 is made of a non-magnetic material and passes through these holes. It is fixed to the circumferential surface of the fixed iron core 15, and the other end is expanded and abutted against the end surface of the connecting ring 16. Further, a support tube 22 is fitted into the reduced diameter portion of the fixed iron core 15 with a gap forming a communication portion 21 with the guide tube 18.
is supported by the valve body 1 so as to surround the valve seat 4a of the valve chamber 4 at its other end.

The support pipe 22 has a pressure fluid introduction hole 23 that opens into the passage 5 of the valve body 1 near the end on the valve body side, and has an appropriate number of outflow holes 22a, . . . in the middle part thereof. A plurality of consecutive rows of outflow holes in the axial direction are arranged at equal intervals.

A movable iron core 27 is inserted into the support tube 22 with a gap 25 between it and the support tube 22, and a movable iron core 27 is provided at one end with a valve member 26 for closing the valve seat 4a. 27 is always biased by a return spring 28 provided between a recess formed on the other end surface and the fixed iron core 15 so that the valve member 26 closes the valve seat 4a. The movable core 27 constitutes the electromagnetic operation section 10 together with the exciting coil 11, the fixed core 15, the magnetic frames 13a and 13b, and the like.

In FIG. 1, reference numeral 29 is a conductive wire that connects the excitation coil 11 to a power source.

In the first embodiment described above, when the exciting coil 11 is not excited, the valve member 26 is moved by the return spring 28.
The valve seat 4a is closed by the valve seat 4a, but the pressure fluid from the inflow port 2 passes through the passage 5 and the pressure fluid introduction hole 23, or from the passage 5 to the communication part 21 and the outflow hole 22a, ... or the cross-shaped distribution hole. 15a and the ejection holes 15b, . . . and flows into the gap 25.

When the exciting coil 11 is excited in this state, the movable core 27 is attracted to the fixed core 15 and slides, and the valve member 26 first slightly opens the valve seat 4a. Due to the initial opening of the valve seat 4a, the fluid in the gap 25 flows from the valve seat 4a to the outflow port 3 along the outer circumferential wall of the movable core 27, and this flow flows through the outflow holes 22a, . . .
The inflow of pressure fluid from the jet holes 15b, . . . continues while the valve member 26 opens the valve seat 4a. On the other hand, the pressure fluid flowing from the pressure fluid introduction hole 23 to the valve seat 4a also flows to the outflow port 3 through the valve seat 4a.

Due to the air bearing effect caused by the pressure fluid flowing into the gap 25 described above, the movable core 27 is held so as not to come into contact with the support tube 22, and furthermore, the pressure fluid from the jet holes 15b, . . . Because of the collision, the sliding speed of the movable core 27 is reduced, and when the gap 20 between the movable core 27 and the fixed core 15 narrows, this narrowed gap 2
Since the pressure fluid inside the movable core 27 acts as a resistance to the sliding movement of the movable core 27, the sliding speed of the movable core 27 is further reduced, and the impact caused by the collision with the fixed core 15 is alleviated.

In this case, if the opening area of the pressure fluid introduction hole 23 is made smaller than the opening area of the valve seat 4a, the ejection hole 1
Since the amount of pressure fluid flowing into the gap 25 through 5b, .

Note that due to the sliding movement of the movable iron core 27, the valve member 26
When the valve seat 4a is opened, the fluid in the gap 25 flows out to the outflow port 3 along the outer peripheral wall of the movable iron core 27, but as the pressure fluid flows out, the pressure fluid from the inflow port 2 flows into the gap 25. is the outflow hole 22a,
...and flows through the ejection holes 15a, ..., so
The flow of the pressure fluid along the outer circumferential wall of the movable iron core 27 continues, while the pressure fluid from the pressure fluid introduction hole 23 also flows out to the outflow port 3.

3 and 4 show a second embodiment of the present invention, in which an inflow port 32 formed in a valve body 31 is communicated with a valve chamber 34 through a passage 35 and a valve seat 34a. , the outflow port 33 is the passage 36
It is communicated with the valve chamber 34 by. Further, the magnetic frame 41 is formed as an integral piece with a rectangular cross section, and the movable iron core 4 is attracted to the fixed iron core 42.
3 is directly inserted into the guide tube 18 with a gap 25 in between, without using a support tube. The movable iron core 43 is provided with a valve member 45 having a through hole 44 on one end surface thereof, and further has a pressure fluid introduction hole 46 communicating with the through hole 44 in the axial direction thereof.
The pressure fluid introduction hole 46 is opened at the end face of the movable iron core 43 by a small-diameter jet hole 47 formed at the bottom of the hole, and has an outflow hole 43a that opens radially from the pressure fluid introduction hole 46. A plurality of rows of outflow holes connected in the axial direction are arranged at equal intervals. As shown in FIG. 4, grooves 48 are cut in the axial direction between these outflow hole rows.

The rest of the structure of the second embodiment is the same as that of the first embodiment, but as shown in FIG.
8 can be omitted.

In the second embodiment, the through hole 44 is provided in the valve member 45.
However, since the movable iron core 43 is provided with the outflow holes 43a, ... and the ejection holes 47, the valve member 45
Even when the valve seat 34a is closed, a small amount of the pressurized fluid from the inflow port 32 flows into the movable core 4.
3 and flows out from the gap 25 to the outflow port 33. Since the force of the air pressure acting on both ends of the movable iron core 43 is approximately balanced due to the ejection of the pressurized fluid from the ejection hole 47, the return spring 28 can be omitted if the attitude of the solenoid valve is considered. The valve member 45 never opens the valve seat 34a.

When the excitation coil 11 is excited in the above-mentioned state, the attractive force of the fixed iron core 42 is applied to the fixed iron core 42 and the movable iron core 4.
The valve member 45 opens the valve seat 34a by suctioning the movable core 43 against the fluid pressure between the inflow port 32 and the outflow port 33.
leaks into This sliding movement of the movable core 43 is decelerated by the reaction force when the pressure fluid ejected from the jet hole 47 collides with the fixed core 42, and when the gap 20 between the movable core 43 and the fixed core 42 further narrows, Since the pressure fluid in the narrowed gap 20 acts as a resistance to the sliding movement of the movable core 43, the sliding speed of the movable core 43 is further reduced, and the impact caused by the collision with the fixed core 42 is alleviated. In this case, although not shown, if a cylindrical protrusion is formed around the ejection hole 47 of the movable core 43 and a recess into which the protrusion is loosely inserted is formed in the fixed core 42, the movable core 43 When the convex portion is inserted into the recess of the fixed core 42, the pressure fluid discharge passage from the jet hole 47 is rapidly contracted, and the movable core 43 is further decelerated, so that the above-mentioned impact is further reduced. It can be done.

In addition, in the second embodiment, the valve member 45 is connected to the valve seat 34.
a is closed, a small amount of pressure fluid from the inflow port 32 flows from the outflow holes 43a,... to the gap 2.
5 and bleeds to the outflow port 33 along the outer peripheral wall of the movable iron core 43, it can be used in cases where such bleed does not pose a problem.

5 and 6 show a third embodiment of the present invention, in which a valve body 51 is installed within the guide pipe 18, and only an inflow port 52 is bored, and an outflow port 53 is bored in the fixed iron core 61. The inflow port 52 is defined by a passage 55 provided in the valve body 51, and the outflow port 53 is defined by a passage 56 provided in the fixed core 61. This space is used as the valve chamber 54, and the valve chamber 54 of the passage 56 communicates with the space inside the passage 56.
The opening end to the valve seat 54a is the valve seat 54a.

The valve chamber 54 includes the guide pipe 18 and the gap 2.
5, and a movable iron core 63 having a valve member 62 at one end for closing the valve seat 54a is inserted. This movable iron core 63 has a pressure fluid introduction hole 64 opened to the passage 55 side, and an appropriate number of discharge holes 63a, . A plurality of discharge hole rows are arranged at equal intervals, and grooves 65, . . . are formed in the axial direction at intermediate positions of the discharge hole rows (see FIG. 6).

Moreover, the fixed iron core 61 in the movable iron core 63
A recess 66 is provided on the surface facing the valve member 62, and the return spring 28 inserted into the recess 66 keeps the movable core 63 in pressure contact with the valve body 51, causing the valve member 62 to open the valve seat 54a. are doing.

On the other hand, an ejection hole 58 is provided in the axial direction of the valve body 51 at a location where the end surface of the movable iron core 63 contacts, and a guide cylinder 59 is provided in the passage 55 that protrudes into the pressure fluid introduction hole 64. is formed.

In the third embodiment, when the excitation coil 11 is not excited, the return spring 28 causes the valve member 62 of the movable core 63 to open the valve seat 54a, so that the pressure fluid from the inflow port 52 is Passage 55, pressure fluid introduction hole 64, outflow hole 63a,...
It flows out from the outflow port 53 through the gap 25 and the like.

When the excitation coil 11 is excited in this state, the fixed iron core 61 attracts the movable iron core 63 and the valve member 62
closes the valve seat 54a and the flow of pressure fluid stops. When the excitation of the excitation coil 11 is released, the movable core 63 is returned by the return spring 28, and the valve member 62 opens the valve seat 54a.
8, the sliding speed of the movable iron core 63 is determined by the pressure fluid from the jet hole 58 provided in the valve body 5.
Since the speed is reduced in the same way as in the first embodiment, the movable iron core 6
The impact caused by the collision between valve body 51 and valve body 51 is alleviated.

In addition, in the third embodiment, similarly to the second embodiment, the pressure fluid from the inflow port 32 flows into the gap 25 from the outflow holes 63a, . . . and flows along the outer peripheral wall of the movable core 63. is prevented from contacting the guide tube 18.

[Effects of the Invention] The present invention provides an ejection hole in one of the end face of the movable iron core or the fixed part facing the end face, through which a part of the pressure fluid flowing through the solenoid valve is ejected toward the opposite face,
The sliding speed of the movable core is reduced by the force generated by the collision of the pressure fluid ejected from the jet hole with the opposing surface and by the braking action of the pressure fluid flowing through the gap narrowed by the sliding motion of the movable core. This reduces the impact caused by the collision between the movable core and the fixed core, etc., and also prevents contact between the two by flowing through the gap between the outer circumferential wall of the movable core and the surrounding fixed outer circumference. Therefore, even if the solenoid valve is operated frequently and used for a long time, fatigue and wear of the movable core and the fixed parts with which it collides and comes into contact are reduced, increasing the life of the solenoid valve.

In addition, the pressure fluid that is ejected into the gap between the end face of the movable core and the fixed part facing it uses the pressure fluid flowing through the solenoid valve and does not require any other pressure source or piping, so its structure is simple. be.

[Brief explanation of the drawing]

1 is a longitudinal sectional front view showing a first embodiment of the present invention, FIG. 2 is a sectional view taken along line A-A in FIG. 1, and FIG. 3 is a longitudinal sectional front view showing a second embodiment of the invention. 4 is a side view of the movable core shown in FIG. 3, FIG. 5 is a longitudinal sectional front view showing a third embodiment of the present invention, and FIG. 6 is a plan view of the movable core shown in FIG. 5. . 2, 32, 52... Inflow port, 3, 33, 5
3...Outflow port, 4a, 34a, 54a...Valve seat, 4a, 34a, 54a...Valve seat, 5, 6, 3
5, 36, 55, 56... passage, 10... electromagnetic operation section, 15b, 47, 58... blowout hole, 20...
Gap, 27, 43, 63...movable iron core.

Claims (1)

[Claims] 1. In a solenoid valve comprising an inflow port and an outflow port for pressure fluid, a passage that communicates both ports, a valve seat formed in the passage, and an electromagnetic operation part that opens and closes the valve seat, a movable iron core in the electromagnetic operation part An ejection hole is provided on either the end face of the solenoid valve or the fixed part facing the same, and a part of the pressure fluid flowing through the solenoid valve is ejected toward the other opposing side, and the ejection hole causes the fluid to eject and collide with the opposing surface. After that, the pressure fluid flowing through the gap between the movable iron core and the outer fixed part surrounding it is reduced to reduce the impact caused by the collision between the end face of the movable iron core and the fixed part facing it, and to keep the movable iron in a state where it is not in contact with the outer fixed part. A solenoid valve characterized by having a means for holding the valve in place.