JP2006052802A - Valve device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve device that can raise the pressure of a peeled-off region formed in the vicinity of the wall of a sleeve, and can narrow the range of the peeled-off region. <P>SOLUTION: The valve device is installed to a hydraulic shovel, for example, and comprises the sleeve 1 that comprises a high-pressure port 2 and a low-pressure port 3, and a valve chamber 4 that communicates to the high-pressure port 2 and the low-pressure port 3; a spool 5 that is arranged in the valve chamber 4 of the sleeve 1 so as to slidable therein, and forms a throttle 6 that can adjust the flow of pressurized oil flowing to the low-pressure port 3 from the high-pressure port 2; and a processing body 20 that is arranged in the downstream of the throttle 6 in the vicinity of the throttle 6, and performs processing for dispersing the flow of the pressurized oil. The throttle 6 is formed in a position where, for example, the high-pressure port 2 and the valve chamber 4 communicate with each other by the spool 5, and the processing body 20 is arranged in the part of the valve chamber 4 that is located between the high-pressure port 2 and the low-pressure port 3. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a valve device that is provided in a construction machine such as a hydraulic excavator and that can suppress noise caused by bubbles generated in a sleeve in which a spool is accommodated.

  FIG. 5 is a cross-sectional view schematically showing a conventional valve device. This prior art is a flow control valve provided in a construction machine such as a hydraulic excavator, and includes a sleeve 1 and a spool 5 that is slidably disposed in the sleeve 1. The sleeve 1 is connected to a high-pressure port 2 through which high-pressure liquid, that is, pressure oil is guided, a low-pressure portion, for example, a low-pressure port 3 that communicates with a tank, and communicates with the high-pressure port 2 and the low-pressure port 3 and accommodates a spool 5. And a valve chamber 4. The spool 5 includes, for example, a large-diameter portion 7 that forms the aperture 6 and a small-diameter portion 8 that is connected to the large-diameter portion 7.

In the flow rate control valve configured as described above, as indicated by the flow line 9, the pressure oil guided to the high pressure port 2 flows into the valve chamber 4, and a part of this pressure oil passes through the throttle 6 and flows into the low pressure port. Flows to the 3rd side. As a result, the flow rate of the pressure oil supplied from the high pressure port 2 to a conduit (not shown) is controlled. In addition, there exists a thing shown by patent document 1 as an example of the valve apparatus as mentioned above.
Japanese Patent Laid-Open No. 10-160002

  In the prior art as shown in FIG. 5 described above, high pressure oil flowing near the wall 10 forming the high pressure port 2 of the sleeve 1 passes through the throttle 6 as shown by the streamline 11 in FIG. When flowing into the chamber 4, the flow direction of the pressure oil is bent at a substantially right angle. As a result, a peeling phenomenon occurs in which a peeling region 12 composed of a vacuum cavity is formed in the vicinity of the wall of the valve chamber 4 of the sleeve 1 downstream of the throttle 6, for example. In the low pressure peeling region 12, a large amount of air dissolved in the pressure oil is released, and these air bubbles are mixed into the pressure oil and flow downstream. At this time, since the downstream pressure is higher than the pressure in the separation region 12, a phenomenon occurs in which bubbles once generated are crushed again. When the bubbles are crushed in this way, an impact is given to the flow of pressure oil around the bubbles. As a result, vibration is generated and noise is generated. This noise is generally called cavitation sound.

  As the pressure in the separation region 12 decreases, the bubbles tend to increase, and as the range of the separation region 12 increases, the number of bubbles increases. When the bubbles become large and the number increases, the total volume of the bubbles to be crushed becomes large, and a large noise is generated. For this reason, there has conventionally been a desire to suppress the noise associated with the above-described peeling region 12 formed at a position near the downstream of the diaphragm 6 as much as possible.

  The present invention has been made from the above-described prior art, and its purpose is to increase the pressure in the separation region formed near the wall of the sleeve, and to narrow the range of the separation region. Is to provide.

  In order to achieve the above object, the present invention is a sleeve having a high pressure port and a low pressure port, a valve chamber communicating with the high pressure port and the low pressure port, and a slidable arrangement in the valve chamber of the sleeve. A valve device comprising a spool that forms a throttle capable of adjusting the flow of liquid from the high-pressure port to the low-pressure port, disposed downstream of the throttle and in the vicinity of the throttle, It is characterized by having a processing body that performs processing to distribute the flow.

  In the present invention configured as described above, the liquid such as the pressure oil that has passed through the throttle is dispersed by the treatment body, so that a part of the dispersed flow reaches the vicinity of the wall of the sleeve located downstream of the throttle. This makes it difficult to form a separation region near the wall of the sleeve downstream of the throttle. Even if a separation region is formed, the pressure in the separation region can be increased by facilitating the flow of part of the pressure oil dispersed in the separation region, and the release of air contained in the liquid. And the generation of bubbles can be suppressed. Accordingly, the generation of large bubbles can be suppressed. In addition, the range of the separation region can be narrowed by the inflow of a part of the pressure oil into the portion where the separation region has been formed in the past, and the number of bubbles generated can be reduced. As a result, the total volume of bubbles that are crushed again after being mixed into the pressure oil can be reduced.

  Further, the present invention is the above invention, wherein the spool forms the throttle at a position where the high pressure port and the valve chamber communicate with each other, and the processing body is positioned between the high pressure port and the low pressure port. It arrange | positions in the part of the said valve chamber to do.

  In the present invention configured as described above, since the spool passes through the throttle from the high pressure port and the liquid flowing into the valve chamber is dispersed by the processing body, a separation region is formed in the vicinity of the wall of the sleeve forming the valve chamber. It is hard to be done.

  The present invention is characterized in that, in the above invention, the throttle is formed at a position where the valve chamber and the low pressure port communicate with each other, and the processing body is disposed in the low pressure port.

  In the present invention configured as described above, the liquid that is guided from the high pressure port to the valve chamber and passes through the throttle and flows into the low pressure port is dispersed by the processing body, so that it is separated near the wall of the sleeve forming the low pressure port. Regions are difficult to form.

  Further, the present invention is characterized in that, in the above invention, the liquid is pressure oil and is provided in a construction machine.

  In the present invention, the flow of the liquid that has passed through the throttle is dispersed by the treatment body, whereby the pressure in the separation region can be increased, the range of the separation region can be narrowed, and the bubbles generated accordingly can be reduced. And the number of bubbles can be reduced. Accordingly, the total volume of bubbles mixed with the pressure oil and crushed again by the pressure of the pressure oil can be reduced, and noise generated by the crushed can be reduced as compared with the conventional case.

  Hereinafter, the best mode for carrying out the valve device according to the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view schematically showing a first embodiment of a valve device according to the present invention. The first embodiment shown in FIG. 1 is also a flow control valve provided in, for example, a hydraulic excavator, and the same components as those shown in FIG. 5 described above are denoted by the same reference numerals.

  That is, the first embodiment also includes a sleeve 1 and a spool 5 that is slidably disposed in the sleeve 1. The sleeve 1 includes a high-pressure port 2 through which high-pressure liquid, that is, pressure oil is guided, and low-pressure. A low pressure port 3 that communicates with a part, for example, a tank, and a valve chamber 4 that communicates with the high pressure port 2 and the low pressure port 3 and accommodates a spool 5. A diameter portion 7 and a small diameter portion 8 connected to the large diameter portion 7 are provided. A throttle 6 is formed at a position where the high pressure port 2 and the valve chamber 4 communicate with each other. These structures are the same as those shown in FIG.

  In particular, the first embodiment includes a processing body 20 that is disposed downstream of the throttle 6 and in the vicinity of the throttle 6 and performs a process of dispersing the flow of the liquid, that is, the pressure oil. That is, the processing body 20 is attached to the small diameter portion 8 of the spool 5 located in the portion of the valve chamber 4 located between the high pressure port 2 and the low pressure port 3. The processing body 20 is composed of, for example, a cylindrical wire mesh 21 having fine eyes and a large number of metal pieces 22 accommodated in the wire mesh 21. A large number of metal pieces 22 and the meshes of the wire mesh 21 are allowed to allow pressure oil to flow.

  Even in the first embodiment, the pressure oil guided to the high-pressure port 2 flows into the valve chamber 4 and a part of the pressure oil flows to the low-pressure port 3 side through the restrictor 6. The flow rate of the pressure oil supplied from the port 2 to a pipe line (not shown) is controlled.

  FIG. 2 is a cross-sectional view showing the main part of FIG. 1, and FIG. 3 is a diagram for explaining the operation of the processing body provided in the first embodiment of the present invention.

  In particular, in the first embodiment, the processing body 20 for dispersing the flow of the pressure oil is provided in the valve chamber 4 downstream of the throttle 6, so that the pressure that has passed through the throttle 6 as shown in FIG. The oil collides with the metal piece 22 of the treatment body 20 and is dispersed. Part of this dispersed flow reaches the vicinity of the wall of the valve chamber 4 of the sleeve 1 located downstream of the throttle 6. This makes it difficult to form a separation region near the wall of the valve chamber 4 of the sleeve 1 downstream of the throttle 6. As shown in FIG. 2, even if the peeling region 23 is formed, the pressure of the peeling region 23 can be increased by facilitating the flow of part of the pressure oil dispersed in the peeling region 23. The release of air contained in the pressure oil can be suppressed, and the generation of bubbles can be suppressed. Along with this, generation of large bubbles can be suppressed.

  As shown in FIG. 3, even if bubbles 24 are generated, these bubbles 24 are likely to collide with the metal piece 24 by being pushed away by pressure oil flowing in later, as indicated by arrows. Therefore, many bubbles 24 disappear.

  Moreover, in this 1st Embodiment, the peeling area | region 23 shown in FIG. 2 can be narrowed by the inflow of a part of pressure oil to the part in which the peeling area | region was formed conventionally, and the number of bubbles which generate | occur | produce is restrained small. be able to.

  As a result, according to the first embodiment, the total volume of the bubbles 24 to be crushed again after being mixed into the pressure oil can be reduced, and noise generated by the bubbles 24 being crushed can be reduced.

  FIG. 4 is a cross-sectional view schematically showing a second embodiment of the present invention. In the second embodiment shown in FIG. 4, a throttle 6 is formed at a position where the valve chamber 4 and the low pressure port 3 communicate with each other, and a processing body 25 that disperses the flow of pressure oil that has passed through the throttle 6 is provided. In the low pressure port 3 in the vicinity of the diaphragm 6. The processing body 25 is also constituted by, for example, a cylindrical metal mesh 26 having fine eyes and a large number of metal pieces 27 accommodated in the metal mesh 26. A large number of metal pieces 27 and the mesh of the metal mesh 26 are allowed to allow pressure oil to flow. Other configurations are the same as those in the first embodiment.

  In the second embodiment configured as described above, the processing body 25 that disperses the flow of the pressure oil is provided in the low pressure port 3 downstream of the throttle 6, so that the pressure oil that has passed through the throttle 6 is treated by the processing body 25. The metal pieces 27 collide and are dispersed. Part of this dispersed flow reaches the vicinity of the wall of the low pressure port 3 located downstream of the restriction 6. This makes it difficult to form a separation region in the vicinity of the wall of the low pressure port 3 downstream of the throttle 6. As shown in FIG. 4, even if the peeling region 28 is formed, the pressure of the peeling region 28 can be increased by flowing a part of the pressure oil dispersed in the peeling region 28. . Further, the peeling region 28 can be narrowed by the above-described inflow of the pressure oil into the peeling region 28. As a result, the same effects as those of the first embodiment described above can be obtained.

  In each of the above embodiments, the flow control valve has been described as the valve device, but the present invention is not limited to this, and may be applied to a pressure control valve or the like.

  Further, in the above, each of the treatment bodies 20 and 25 is composed of the cylindrical wire nets 21 and 26 and the metal pieces 22 and 27. However, the present invention is not limited to this, and the treatment body, for example, a metal wire is spool 5 The small-diameter portion 8 may be wound in a turbulent manner, or may be formed of a foam metal cylinder capable of circulating a liquid such as pressure oil. In short, the treatment body of the present invention only needs to have a configuration that allows the flow of liquid such as pressure oil and disperses the flow direction.

It is sectional drawing which showed typically 1st Embodiment of the valve apparatus which concerns on this invention. It is sectional drawing which shows the principal part of FIG. It is a figure explaining the effect | action of the process body with which 1st Embodiment of this invention is equipped. It is sectional drawing which showed typically 2nd Embodiment of this invention. It is sectional drawing which showed the conventional valve apparatus typically.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sleeve 2 High pressure port 3 Low pressure port 4 Valve chamber 5 Spool 6 Restriction 7 Large diameter part 8 Small diameter part 20 Processing body 21 Metal mesh 22 Metal piece 23 Peeling area 24 Bubble 25 Processing body 26 Metal mesh 27 Metal piece 28 Peeling area

Claims (4)

A sleeve having a high-pressure port and a low-pressure port, and a valve chamber communicating with the high-pressure port and the low-pressure port, and a liquid slidably disposed in the valve chamber of the sleeve, and facing the low-pressure port from the high-pressure port And a spool device that forms a throttle capable of adjusting the flow of
A valve device comprising a processing body which is disposed downstream of the throttle and in the vicinity of the throttle and performs a process of dispersing the liquid flow. In the invention of claim 1,
The spool forms the throttle at a position where the high pressure port communicates with the valve chamber,
The valve device according to claim 1, wherein the processing body is disposed in a portion of the valve chamber located between the high pressure port and the low pressure port. In the invention of claim 1,
The spool forms the throttle at a position where the valve chamber and the low pressure port communicate with each other,
A valve device, wherein the processing body is disposed in the low pressure port. In the invention according to any one of claims 1 to 3,
A valve device characterized in that the liquid is pressure oil and is provided in a construction machine.

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