JP2013238291A - Valve device - Google Patents

Abstract

An object of the present invention is to facilitate processing of a valve device capable of outputting a maximum pressure among a plurality of load pressures.
Each of a plurality of valve bodies connected to each other communicates with a bridge passage that guides load pressure, a communication passage that guides working fluid from a pump, and one end face of a valve body from the other end to the other. A maximum pressure passage 23 penetrating straight into the end surface 1b of the first passage, a connection passage 24 that connects the opening of the communication passage 25 and the highest pressure passage 23, and a connection passage 24 and the communication passage 25. A valve body 22 that opens only when the pressure of the pressure is higher than the pressure of the maximum pressure passage 23, and the communication passage 25 is connected to the continuous maximum pressure passage 23 in parallel via the valve bodies 22, Of the load pressures led to each bridge passage 26, the highest pressure is led to the highest pressure passage 23.
[Selection] Figure 2

Description

  The present invention relates to a valve device that connects a plurality of valve bodies and selects and outputs the highest pressure among the pressures of a load connected to each valve body.

Conventionally, a device shown in FIGS. 3 and 4 is known as this type of valve device.
FIG. 3 is a cross-sectional view of one valve body, and FIG. 4 is a cross-sectional view showing a state in which a plurality of valve bodies 100 of FIG. 3 are connected.
In the switching valve shown in FIG. 3, a spool 3 is slidably incorporated in a spool hole 2 formed in the valve body 100. One end of the spool 3 is provided with a connecting portion 4 for connecting an operation lever (not shown), and the other end is actuated by the spring force of the spring member 6 in the cap 5 fixed to the valve body 100 to achieve this neutrality. Keeps the position.
The spool 3 is alternately formed with a plurality of land portions and annular recesses that are in sliding contact with the inside of the spool hole 2, and the spool 3 is moved to the left or right in the drawing to be described later. Is configured to switch.

The valve body 100 has a pair of actuator ports 8 and 9 and a plurality of passages communicating with the outer periphery of the spool 3.
Specifically, the actuator passages 10 and 11 communicating with the actuator ports 8 and 9, the tank passage 12 connected to the tank, the pump passage 13 connected to the hydraulic pump, the center passage 14 and the bridge passage 15 include a valve body. 100.
A flow rate control valve 16 is provided between the center passage 14 and the bridge passage 15 to block communication between the passages 14 and 15. The flow control valve 16 is partitioned by a partition wall 16a, a communication hole 16b is formed in one chamber, and a spring member 17 is accommodated in the other chamber. In the figure, reference numeral 7 denotes a ring-shaped seal member.

  In the switching valve, when the spool 3 is in the neutral position shown in the drawing, the communication between the actuator passages 10 and 11 and the tank passage 12 or the pump passage 13 is blocked by the land portions.

From this state, for example, when the spool 3 moves to the left in the figure, one actuator passage 11 communicates with the bridge passage 15 via the annular recess on the right end side of the spool 3 and is formed in the central land portion. The pump passage 13 and the center passage 14 communicate with each other through the notch n.
When the center passage 14 and the pump passage 13 communicate with each other and the pressure of the center passage 14 overcomes the spring force of the spring member 17 of the flow control valve 16, the flow control valve 16 moves and the center passage 14 and the bridge passage 15 Communicate. That is, pump discharge oil is supplied to the actuator port 9.

At this time, the other actuator passage 10 communicates with the tank passage 12 via the annular recess on the left end side of the spool 3, so that the return oil from the actuator port 8 is returned to the tank.
When the spool 3 moves to the right in the drawing, the other actuator passage 10 communicates with the bridge passage 15 via the annular recess on the left end side of the spool 3, and the actuator passage 11 communicates with the tank passage 12. .
As described above, when the spool 3 is switched to any one, any one of the actuator ports 8 and 9 and the bridge passage 15 communicate with each other, and a load pressure of an actuator (not shown) acts on the bridge passage 15. Become.
3 are a large-diameter portion 18a of the communication passage 18 described later and a large-diameter portion 20a of the pressure passage 20, which are formed on one end face 1a described later.

As shown in FIG. 4, the valve body 100 is formed with a communication passage 18 that opens to one end face 1 a and communicates with the bridge passage 15. A large-diameter portion 18a is formed on the opening side of the communication path 18, and a high-pressure selection valve 19 is incorporated in the large-diameter portion 18a.
Further, in the valve body 100, a pressure passage 20 penetrating from the one end face 1a to the other end face 1b is formed at a position not intersecting with the bridge passage 15 and the communication passage 18. The opening on the one end face 1a side of the pressure passage 20 is a large-diameter portion 20a, and the large-diameter portion 20a is connected to the large-diameter portion 18a of the communication passage 18 as indicated by a broken line in FIG. It is configured.

  The other opening 20 b of the pressure passage 20 is formed at a position where it is connected to the large diameter portion 18 a on the one end face 1 a side of the adjacent valve body 100. The pressure passage 20 is composed of a first passage portion 20c and a second passage portion 20d in order to connect the large-diameter portion 20a and the opening 20b that are opened at both end faces of the valve body 100. A bend is formed.

  In such a valve device, the load pressure led to the bridge passage 15 of one valve body 100 is led from the communication passage 18 to the pressure passage 20, and the pressure in the pressure passage 20 is adjacent to the left in the figure. The larger load pressure is guided to the high-pressure passage 20 in opposition to the load pressure introduced to the communication passage 18 of the adjacent valve body 1 through the high-pressure selection valve 19 incorporated in 100.

As described above, the higher load pressure is introduced between the adjacent valve bodies 100, 100 into the high-pressure passage 20, and therefore, in the plurality of valve bodies 100 connected to the leftmost high-pressure passage 20 in FIG. The maximum load pressure among the load pressures is derived.
Such maximum load pressure can be used in another hydraulic circuit connected to the valve device. For example, it can be led to a regulator of a variable displacement pump, and the tilt angle can be controlled according to this maximum load pressure.
Patent Document 1 also discloses a configuration in which two load pressures are sequentially compared to extract the maximum load pressure, as in the above-described apparatus.

JP-A-5-149457

In the conventional valve device described above, the opening 20b on the other end face side of the pressure passage 20 formed in each valve body 100 is configured to face the communication passage 18 of the adjacent valve body 100. A bent portion is formed in the passage 20. In order to form a pressure passage having such a bent portion, the first passage portion 20c and the second passage portion 20d must be formed from both end faces of the valve body 100, respectively. End up.
Further, in order to connect the first and second passage portions 20c and 20d formed from both sides inside the valve body 100, machining accuracy is also required.
Further, in this valve device, the maximum load pressure is guided to the leftmost high pressure passage 20 in the connected state shown in FIG. 4. Thus, it was necessary to form the maximum pressure output passage 21 that penetrates the valve body 100 at a position different from the cross section shown in FIG.

  An object of the present invention is to facilitate processing of a valve device that can output the maximum pressure among a plurality of load pressures.

  The present invention is a valve device in which a plurality of valve bodies are connected, each valve body having a spool slidable in the valve body, a pump passage connected to the pump, and switching of the spool. A bridge passage that communicates with the pump passage, a communication passage that communicates with the bridge passage and that guides the working fluid from the pump, and a maximum pressure passage that passes straight from one end face of the valve body to the other end face. A connection passage that connects the communication passage and the highest pressure passage, and is provided between the connection passage and the communication passage, and is opened only when the pressure in the communication passage is greater than the pressure of the highest pressure passage. A valve body to be valved, the opening of the highest pressure passage on one end face side of the valve body, and the highest pressure passage on the other end face of the adjacent valve body. And communicating one end face and the other end face of the adjacent valve bodies, the highest pressure passage is linearly continuous across a plurality of valve bodies, and each of the communication passages is the continuous passage. The maximum pressure passage is connected in parallel via the valve bodies to the highest pressure passage, and the highest pressure among the load pressures led to the bridge passages is led to the highest pressure passage via the connection passage. It is characterized by that.

According to the present invention, the highest pressure passage for selecting and outputting the highest load pressure among the plurality of load pressures is formed through the straight line from one end face of the valve body to the other end face, so that the processing is easy. It is.
In addition, since the communication passage connected to the bridge passage of each valve body is provided in parallel in the highest pressure passage, the highest load pressure can be output from either side of the highest pressure passage. Therefore, it is not necessary to form a separate passage for outputting the maximum load pressure.

FIG. 1 is a sectional view of a valve body according to an embodiment of the present invention. FIG. 2 is a sectional view showing a state in which a plurality of valve bodies shown in FIG. 1 are connected. FIG. 3 is a sectional view of a valve body of this conventional valve device. 4 is a cross-sectional view of a state in which a plurality of valve bodies shown in FIG. 3 are connected.

1 and 2 show an embodiment of the present invention.
FIG. 1 is a cross-sectional view of one valve body 1 used in the valve device of this embodiment, and FIG. 2 is a cross-sectional view of the valve body 1 connected in three. However, the number of concatenations is not limited to three and may be any number.
In this valve body 1, the same reference numerals as those in FIGS. 3 and 4 are used for the same components as those in the conventional valve body 100 shown in FIGS.
However, the bridge passage 26 of this embodiment described later functions in the same manner as the conventional bridge passage 15, but uses a different reference from the conventional bridge passage 15 because of its different cross-sectional shape.

The description of the same components as those of the conventional valve device is omitted, and the description of the same configuration is simplified.
Similarly to the valve body 100, the valve body 1 of this embodiment is provided with the spool 3 so as to be slidable, and the passage formed therein is switched depending on the switching position of the spool 3.

Specifically, when the spool 3 is in the neutral position shown in the drawing, the communication between the actuator passages 10 and 11 and the tank passage 12 or the pump passage 13 is blocked by the land portions.
From this state, when the spool 3 moves to the left in the figure, one actuator passage 11 and the pump passage 13 communicate with each other, and the other actuator passage 10 and the tank passage 12 communicate with each other as in the conventional case. .
When the spool 3 moves to the right in the figure, one actuator passage 11 and the tank passage 12 communicate with each other, and the other actuator passage 10 and the pump passage 13 communicate with each other.

As described above, when the spool 3 is switched to any one, any one of the actuator ports 8 and 9 and the bridge passage 26 communicate with each other, and a load pressure of an actuator (not shown) acts on the bridge passage 26. Become.
In addition, the broken line shown in FIG. 1 is the large diameter part 25a of the communicating path 25 mentioned later, and the highest pressure channel | path 23, These are formed in the one end surface 1a mentioned later.

As shown in FIG. 2, the valve body 1 of this embodiment is formed with a communication passage 25 that opens to one end face 1 a and communicates with the bridge passage 26. A large-diameter portion 25a is formed on the opening side of the communication passage 25, and a check valve 22 constituting the valve body of the present invention is incorporated in the large-diameter portion 25a.
Further, in the valve body 1, a maximum pressure passage 23 that penetrates in a straight line from the one end face 1a to the other end face 1b is formed at a position that does not intersect with the bridge passage 26 and the communication passage 25. This maximum pressure passage 23 is a passage which continues linearly over all the valve bodies 1 as shown in FIG.
The large diameter portion 25a constitutes the opening of the communication passage of the present invention formed on one end face 1a of the valve body 1.

Further, a concave portion 24 including an opening of the highest pressure passage 23 and a large diameter portion 25a of the communication passage 25 is formed on one end face 1a of each valve body 1, and as shown by a broken line in FIG. The maximum pressure passage 23 and the communication passage 25 are connected by 24. That is, the recess 24 formed in the one end face 1a constitutes the connection passage of the present invention.
As described above, the check valve 22 is incorporated in the large-diameter portion 25a of the communication passage 25 connected to the highest pressure passage 23 by the concave portion 24. The pressure on the high pressure passage 23 side acts as a back pressure, and the valve is opened only when the pressure on the communication passage 25 side, that is, the load pressure introduced to the bridge passage 26 is larger than this pressure, and the communication passage 25 and the maximum pressure are opened. The passage 23 communicates with the passage 23.

In such a valve device, each communication passage 25 is connected in parallel via a check valve 22 to a linear maximum pressure passage 23 penetrating all the valve bodies 1 connected. The load pressure on the side of each communication passage 25 is guided to the highest pressure passage 23 only when the load pressure is higher than the pressure of the highest pressure passage 23.
Therefore, the highest pressure of all the load pressures is guided to the highest pressure passage 23.

In the valve device of this embodiment, the maximum pressure passage 23 continuously penetrates all the valve bodies 1, and processing from only one end face 1 a side of each valve body 1 is sufficient. Therefore, it is not necessary to form from both sides like the conventional pressure passage 20, and processing is easy.
Further, if there is a bent portion in the path as in the conventional pressure path 20, the pressure loss increases. However, in this embodiment, since the total maximum pressure path 23 is in a straight line, the pressure loss is reduced and the maximum load pressure is reduced. It is possible to output efficiently.

Further, since the maximum load pressure can be output from any end of the maximum pressure passage 23 that is continuous in a straight line, for example, when the maximum pressure is fed back to the pump, the conventional maximum pressure output shown in FIG. There is no need to form the passage 21. Therefore, it is possible to reduce processing costs and improve productivity.
In this embodiment, since the maximum pressure passage 23 is formed in a straight line, the bridge passage 26 has a cross-sectional shape similar to that of the conventional bridge passage 15 shown in FIG. There is no need to avoid the shape. Therefore, the cross-sectional area of the bridge passage 26 can be increased, and the pressure loss in the bridge passage 26 can be reduced as compared with the conventional bridge passage 15.

In this embodiment, since the passage connecting the communication passage 25 and the maximum pressure passage 23 is formed as the recess 24 on one end face of the valve body 1, the processing is easy.
However, the connection passage may be formed by a drill hole formed so as to penetrate the highest pressure passage 23 and communicate with the communication passage 25 from the upper side in FIG. 2 instead of on the one end face 1a.

  It can be applied to a device that selects and uses the highest pressure among a plurality of load pressures.

DESCRIPTION OF SYMBOLS 1 Valve body 1a One end surface 1b The other end surface 3 Spools 8, 9 Actuator port 22 (Valve body) Check valve 23 Maximum pressure passage 24 (Connection passage) Recess 25 Communication passage 25a (Open) Large diameter Part 26 Bridge passage

Claims (2)

A valve device in which a plurality of valve bodies are connected,
Each valve body has
A spool slidable in the valve body;
A pump passage connected to the pump;
A bridge passage communicating with the pump passage by switching the spool;
A communication path that communicates with the bridge path and that guides the working fluid from the pump;
A maximum pressure passage that passes straight from one end face of the valve body to the other end face;
A connection passage for communicating the communication passage and the highest pressure passage;
A valve body provided between the connection passage and the communication passage, and opened only when the pressure in the communication passage is larger than the pressure of the highest pressure passage;
The opening of the highest pressure passage on one end face side of the valve body communicates with the opening of the highest pressure passage on the other end face of the adjacent valve body, and one end face and the other end face of the adjacent valve body And
The maximum pressure passage continues linearly across a plurality of valve bodies,
The communication paths are connected in parallel to the continuous maximum pressure path via the valve bodies,
A valve device configured such that the highest pressure among the load pressures led to each bridge passage is led to the highest pressure passage through the connection passage.   A recess including an opening of the communication passage and an opening of the highest pressure passage is formed on one end surface of the valve body, and the connection passage that connects the communication passage and the highest pressure passage is formed by the recess. Item 2. The valve device according to Item 1.

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