JPH0434034B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a seat-type valve, in particular, a seat-type valve, in which a primary port and a secondary port are opened, and a seat is inserted into a valve hole in which a seat is formed between these ports. This is a seat type valve in which a valve body seated on the valve body is freely movable, and not only does it allow free flow in the forward direction from the primary port to the secondary port, but also allows flow from the secondary port to the primary port by external operation, etc. This invention relates to a seat type valve that also allows free flow in the opposite direction.

(Prior art) This type of seat-type valve is used in Hydraulic Technology, '80, 1 "About Hydrologic Systems" (Nippon Engineering Publishing)
P50) and is already known.

As shown in FIG. 5, this device connects a rear chamber 53 of a valve body 52 that is slidably installed in a valve hole 51 and a secondary port 54 that opens into the valve hole 51 through a throttle 5.
5, and when the pressure on the primary port 57 side is higher than the pressure on the secondary port 54 side, the back chamber 53 is connected to the secondary port 54 side, which is the low pressure side. Since it is released through the passage 56, the pressure on the primary port 57 side moves the valve body 52 to the right, causing free flow in the forward direction from the primary port 57 to the secondary port 54, while the secondary port When the pressure on the side of the secondary port 54 becomes higher than the pressure on the side of the primary port 57, the pressure on the side of the secondary port 54 acts on the back chamber 53 through the passage 56, and the pressure on the side of the valve body 52
is closed to prevent a reverse flow from the secondary port 54 to the primary port 57.

Furthermore, in order to enable free flow in the opposite direction, a passage 60 is provided that communicates the back chamber 53 and the tank 59, and an on-off valve 61 is interposed in the passage 60. Thus, by switching the on-off valve 61 to a position that allows flow from the back chamber 53 to the tank 59 and opening the back chamber 53 to the tank 59, the pressure on the secondary port 54 side can be reduced. When becomes higher than the pressure on the primary port 57 side, the pressure on the secondary port 54 side moves the valve body 52 to the right, allowing free flow in the opposite direction from the secondary port 54 to the primary port 57. That's how I do it.

(Problems to be Solved by the Invention) However, in the conventional device, when allowing free flow in the opposite direction, the secondary port 54 and the tank 59 are connected through the passages 56 and 60. Even if a throttle 55 is interposed in the passage 56 for communication, when the pressure on the secondary port 54 side increases, the amount of drain to the tank 59, that is, the amount of hydraulic oil that becomes external drain increases significantly. There was a problem.

Therefore, an object of the present invention is to devise the structure of the passage through which the hydraulic oil in the rear chamber 53 enters and exits during the free flow in the reverse direction, and to enable the free flow in the reverse direction. The point is to prevent drainage from occurring.

(Means for solving the problems) The configuration of the present invention will be explained based on FIG.
The primary port 1 and the secondary port 2 are opened, and a valve body 6 seated on the seat 5 is movably housed in the valve hole 4 in which a seat 5 is formed between the ports 1 and 2. A first passage 9 that communicates between the back chamber 7 of the body 6 and the secondary port 2, and a second passage 10 that communicates the back chamber 7 and the primary port 1 are provided, and the first passage 9 A throttle mechanism 11 is installed, and a check valve 12 that only allows flow from the back chamber 7 to the primary port 1 to the second passage 10 opens and closes the flow from the back chamber 7 to the primary port 1. An opening/closing means 13 is interposed therebetween.

(Function) By operating the opening/closing means 13, the second passage 1
By blocking the flow of hydraulic oil from the rear chamber 7 to the primary port 1 via the rear chamber 7, it is possible to allow only free flow from the primary port 1 to the secondary port 2, as in the conventional case. That is, when the pressure on the primary port 1 side is higher than the pressure on the secondary port 2 side, the check valve 12 installed in the second passage 10 closes the air from the primary port 1 to the back chamber 7.
While the flow of hydraulic oil to the rear chamber 7 is communicated with the secondary port 2, which is on the low pressure side, the valve body 6 is opened by the pressure on the primary port 1 side. . Conversely, when the secondary port 2 side pressure becomes higher than the primary port 1 side pressure, the secondary port 2 side pressure acts on the back chamber 7 via the first passage 9, so that the valve body 6 is operated to close.

On the other hand, by operating the opening/closing means 13,
By allowing the flow from the back chamber 7 to the primary port 1 through the passage 10, when the pressure on the secondary port 2 side becomes higher than the pressure on the primary port 1 side, the back chamber 7 is switched to the low pressure side. Therefore, free flow in the opposite direction from the secondary port 2 to the primary port 1 becomes possible. At this time, hydraulic oil flows out from the secondary port 2 to the primary port 1 side through the first passage 9 and second passage 10 that have the throttle mechanism 11, but this hydraulic oil flows into the internal drain. Therefore, external drainage does not occur as in the conventional case.

(Example) The seat type valve shown in Fig. 1 is a seat type valve according to the present invention, which has a check function that allows free flow only from the primary port 1 to the secondary port 2, and also has a check function that allows free flow only from the primary port 1 to the secondary port 2. Free flow can also be selected.

Specifically, a valve hole 4 is formed in the valve body 3, and the primary port 1 is opened at one end of the valve hole 4.
A secondary port 2 is opened in the inner circumferential wall at one end. Further, each port 1 in the valve hole 4,
An annular seat 5 is formed between the valve holes 4 and 2, and a valve body 6 that is seated on the seat 5 is slidably inserted into the valve hole 4. Further, a back chamber 7 is formed on the back side of the valve body 6 in the valve hole 4, and a return spring 8 for pressing the valve body 6 toward the seat 5 is installed inside the back chamber 7. ing.

In the seat-type valve configured as above, a first passage 9 communicates between the back chamber 7 of the valve body 6 and the secondary port 2, and a second passage communicates between the back chamber 7 and the primary port 1. 10, a throttle mechanism 11 is interposed in the first passage 9, and a check valve 12 that allows flow only from the back chamber 7 to the primary port 1 in the second passage 10; An opening/closing means 13 for opening and closing the flow from the back chamber 7 to the primary port 1 is interposed.

The opening/closing means 13 is a two-position electromagnetic valve, which is in the left position when not energized to block the flow from the rear chamber 7 to the primary port 1, and is in the right position when energized. position to allow flow from the rear chamber 7 to the primary port 1.

Hereinafter, the operation of the seat-type valve will be explained.

[1] First, a case where only flow from the primary port 1 to the secondary port 2 is allowed will be explained.

In this case, the opening/closing means 13 is de-energized to prevent the flow from the back chamber 7 to the primary port 1.

Thus, when the pressure on the primary port 1 side becomes higher than the pressure on the secondary port 2 side, the check valve 12 interposed in the second passage 10 acts,
While the communication between the back chamber 7 and the primary port 1 is cut off, the back chamber 7 and the secondary port 2 are constantly communicated via the first passage 9. It will be maintained at a low pressure on the secondary port 2 side.

Therefore, when the valve body 6 is pressed rightward by the high pressure on the primary port 1 side, the valve body 6 directs the hydraulic oil in the back chamber 7 through the first passage 9 to the secondary port. It moves to the right while discharging to the 2nd side. As a result, the valve body 6 separates from the seat 5, and free flow in the forward direction from the primary port 1 to the secondary port 2 occurs.

Conversely, when the pressure on the secondary port 2 side becomes higher than the pressure on the primary port 1 side, the flow from the back chamber 7 to the primary port 1 via the second passage 10 is stopped by the action of the opening/closing means 13. Therefore, this secondary port 2 side pressure acts on the back chamber 7 via the first passage 9. On the other hand, since the pressure receiving surface 6a on the back chamber 7 side is made larger than the pressure receiving surface 6b facing the secondary port 2 on the front side of the valve body 6,
The valve body 6 is pressed leftward by the high pressure on the secondary port 2 side acting on the back chamber 7,
The user is seated on the seat 5. Therefore,
Free flow in the opposite direction is blocked.

[] Next, a case where a free flow in the opposite direction from the secondary port 2 to the primary port 1 is also generated will be described.

In this case, the opening/closing means 13 is energized to set it in a position that allows flow from the rear chamber 7 to the primary port 1.

Thus, since both the opening/closing means 13 and the check valve 12 allow flow from the back chamber 7 to the primary port 1, the secondary port 2
When the side pressure becomes higher than the primary port 1 side pressure, hydraulic oil flows from the secondary port 2 to the primary port 1 via the second passage 10, and the pressure in the back chamber 7 decreases to Mechanism 11
Therefore, the pressure on the primary port 1 side is low pressure.

Therefore, the valve body 6 is pressed in the right direction by the high pressure on the secondary port 2 side acting on the pressure receiving surface 6b, and causes the hydraulic oil in the back chamber 7 to flow through the second passage 10. While being pushed toward the primary port 1 side, it moves to the right and leaves the sheet 5, resulting in a free flow in the opposite direction from the secondary port 2 to the primary port 1.

In addition, in the case of [ ], as before,
Free flow is allowed from the primary port 1 to the secondary port 2, and when the pressure on the primary port 1 side becomes higher than the pressure on the secondary port 2 side, the check valve 12 acts and the The flow from the primary port 1 to the secondary port 2 through the second passage 10 is blocked, and the free flow from the primary port 1 to the secondary port 2 is prevented, acting in the same manner as in the case [] above. It happens.

Further, as the opening/closing means 13, as shown in FIG. 2, a direct-acting seat-type solenoid valve may be used, in which a single poppet 20 seated on a seat 19 is operated by a solenoid 21. Furthermore, as shown in FIG. 3, a small poppet 23 is movably installed inside the large poppet 22, and
A two-stage seat type solenoid valve in which the valve 3 is operated with the solenoid 24 may be used.

Further, as the opening/closing means 13, a hydraulic pilot type pilot check valve as shown in FIG. 4 may be used.

(Effects of the Invention) As described above, according to the present invention, the free flow between the primary port 1 and the secondary port 2 can be selected in the same way as in the past, While always allowing free flow to
By switching the opening/closing means 13, it is possible to select free flow in the opposite direction from the secondary port 2 to the primary port 1, and at the same time, it is possible to prevent external drain from occurring at all.

Therefore, it is also possible to eliminate the need for an external drain port.

[Brief explanation of drawings]

1 to 3 are explanatory diagrams of one embodiment of the present invention, in which FIG. 1 is a hydraulic circuit diagram, FIG. 2 is an embodiment of the opening/closing means used in the embodiment of FIG. FIG. 4 is a hydraulic circuit diagram of another embodiment of the present invention, and FIG. 5 is a hydraulic circuit diagram of a conventional example. 1...Primary port, 2...Secondary port, 4...
Valve hole, 5... Seat, 6... Valve body, 7... Back chamber, 9... First passage, 10... Second passage, 11...
... Throttle mechanism, 12... Check valve, 13... Opening/closing means.

Claims (1)

[Claims] 1 The primary port 1 and the secondary port 2 are opened, and a valve body 6 seated on the seat 5 is movably housed in the valve hole 4 in which a seat 5 is formed between the ports 1 and 2. Back chamber 7 of valve body 6
and a first passage 9 communicating with the secondary port 2;
A second passage 10 communicating between the back chamber 7 and the primary port 1 is provided, a throttle mechanism 11 is interposed in the first passage 9, and a second passage 10 is provided.
A seat characterized in that a check valve 12 that allows flow only from the back chamber 7 to the primary port 1 and an opening/closing means 13 that opens and closes the flow from the back chamber 7 to the primary port 1 are interposed therein. Shaped valve.