JPS58178067A - Double check valve - Google Patents

Abstract

PURPOSE:To provide a check valve, whose primary function is to shut one of the passages according to the pressure difference between pressure fluids incoming in two directions and send off pressure fluid from the other passage, with another function so as to close the supply sides of the pressure fluids in the two directions in the event of pressure drop owing to damage, etc. in the line on the send-off side. CONSTITUTION:Both of No.1 valve elements 8a, 8b are opened when the pressures of the pressure fluid lead to intake ports 2, 3 of a valve casing 1 are larger than the set load of No.1 spring 11 and equal each other, and the pressure fluid comes in passages 9a, 9b to open No.2 valve elements 10a, 10b to be send out of an outlet 4 through a through hole 6 and passage 7. When either of the pipings connected with these intakes 2, 3 is damaged to cause release to the atmosphere, No.2 valve element 10a or 10b on the damaged side shuts the passage 9a or 9b through the action of No.2 spring 12a or 12b. When the line from the outlet 4 is damaged, No.1 valve element 8a, 8b shut the intakes 2, 3 to maintain the residual pressure in the pressure tank.

Description

[Detailed Description of the Invention] 7: The invention relates to a double manual valve (C) connected to a pressure fluid piping line.

Purpose of the present invention Id: Due to the pressure difference between pressure fluids from two directions, one passage is fully closed and pressure fluid is sent out from the other passage.
When the pressure decreases due to damage to the thread path of the 1111 (1111), a double-sided valve is provided which has the ability to close the two-way pressure fluid supply (1111).

Regarding the example f of J''JJ lower A Ming, explanation 11 is based on Figure 1 F.
"do.

11d' is a valve casing, which receives pressure fluid at both ends in the Nl'l direction. 4. An axial tF sleeve 5 is fitted into the valve casing 1, and this sleeve 5 is provided with through holes 6 that allow the intake port 2.3 and the delivery port 4 to communicate with each other. [A passage 7 is formed.

Furthermore, the inner V of the sleeve 5 has the respective receiving ports 2.3.
A first valve body 8a, sb is fitted so as to be slidable in the axial direction, and the through hole 6 of the sleeve 5 is opened only when the receiving port 2.3 is opened. A passage 9a communicating with.

9b is provided. Second valve bodies 10a and 10b are provided inside the passages 9as and 9b so as to be openable and closable.

Next, between the backs of the valve bodies 8a and 8b of both boxes 1,
A first spring 11 with a set load that presses the valve bodies 8a and 8b in the closing direction is interposed [7, 1, Ryokawa 2 valve body 1]
A second valve body 10a11 is installed on the back surface of each of 0a and 10b.
Two springs 12a and 12b with a small set load are installed to press the spring 0b in the closing direction. Further, a breathing hole 13 is provided in the sleeve 5 and the valve casing IK in order to communicate the space inside the sleeve 5 between the first valve bodies 8a, 8b with the outside air.

Since the non-inventive structure is as described above, both receiving ports 2.3
F When the pressure fluid to be introduced is larger than the set load of the first spring 11 and has the same pressure, both box 1 valve bodies 8a and sb open at I/7'' and enter the passage 9a%911 to the second valve body. 10a and 10b are opened to form a through hole 6 and a passage 7.
Send via [ ] 4 and send. Here, in case the intake port 2
．． If either one of the pressure 4 ink piping connected to 3 is damaged and is opened to atmospheric pressure, the second valve body 10a or 10b on the damaged side is connected to the first 2 spring 12a or
2b In addition, pressure from the undamaged side immediately closes the passage 9a or 9b, creating a double-check action that prevents normal (till) pressure from being released into the atmosphere.The pressure from the damaged side is applied to the first spring. When the load falls below the set load of 11, the first valve element 8a and 8b close the receiving port 2 and 3 on the damaged side.Therefore, the pressure from the normal (1111) continues to be sent to the outlet 4.

Furthermore, if the thread path from the outlet port 4 is damaged and the pressure fluid is released to atmospheric pressure, and the pressure in the pressure tank decreases below the set load of the first spring 11, the first valve body 8a, 8b Close the intake port 2.3 [-1 Preserve the residual pressure in the pressure tank by blocking the outlet to the outlet 4''?h
It is. In addition, both boxes 1 valve body 8a, ! due to the movement Jf of the first valve body 8a, 8b. (The space between b performs a breathing action by the breathing hole 13F, and smoothes the movement of the valve bodies 8a and 8b.

Conventionally, in the brake system L of a trailer, the front tank 20a and rear tank 2()b of the air tank 20 are connected to the inlet IC of a normal double check valve 21, as shown in FIG.
2 e was connected, and the protection valve 22 was connected to the trailer via the air cock 23 k and the emergency link 24 [. This is a 25-piece brake valve, and its operation causes the front tank 20a to
Alternatively, the air pressure from the trailer tank 20b is supplied to the brake system of the tractor, and is also supplied to the brake system of the trailer via the double check valve 26, the II cylinder valve 27, and the service coupling 28. Therefore, if the tractor's Freon 14U11 brake system is damaged, close the double check valve 21.
) - Damage to the emitter line system of A (In the case of F, the pressure in the emtank 20 is maintained without releasing it to the atmosphere by closing the protection valve 22. This is a separate component from the protection valve 22, which increases the cost and the number of man-hours required to assemble the piping.

However, as shown in FIG. 3, by assembling only the double check valve 29 invented by KX instead of the conventional double check valve 21, the conventional protection valve 22
This eliminates the need to install a brake system, simplifies the brake system while satisfying the emergency flaking ability, and reduces costs.

Note that if the front tank 20a or the rear tank 20b is damaged, the second valve body 10a or 10 on the damaged side
b was immediately damaged by the second spring 12a or 1d 12b and the normal side pressure 111] receiving port 2 or 3
Since the tank is closed, there is no loss of pressure in the tank on the normal side, and the emergency (011) has the effect of maintaining a full tank.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a double check valve according to the present invention, Fig. 2 is a piping diagram of a conventional trailer lubricant system, and Fig. 3 is a cross-sectional view of a double check valve according to the present invention. - Piping diagram of Gissisnum. 1...-valve casing, 2.3-... receiving port, 4-
...Outlet port, 5...Sleeve, 6...Through hole, 7--
-Passage, 8a, 8b---First valve body, 9a, 9b-
"Passage, 1.Oa, 10b...a 2nd valve body, 11-
--First spring, 12a, 12b...Second spring, 13...Breathing hole. (7) Figure 1 Figure 2 Figure 3 27 28

Claims (1)

[Claims] The valve casing is provided with a pressure fluid reception port at both ends in the axial direction, and a discharge port in a direction perpendicular to the axis between the two reception ports, and a pressure fluid 11 is provided in the valve casing in the axial direction.
A through hole is opened in this sleeve to connect the respective inlet and outlet ports, and the two inlets are connected to the inside of the sleeve. A first valve body that opens and closes is slidably fitted in the axial direction, and a passage communicating with the first valve body (C) is provided in the first valve body only when the front ife receiving port is open. On this passage, a second valve body 1p which can be opened and closed is provided inside the first valve body!
A first spring, which is a set load, is placed between the back surfaces of the valve bodies to press the first valve body of both men in the direction of closing, and a set load is placed between the backs of the two valve bodies of the two boxes, and a spring is placed between the backs of the two valve bodies to press the second valve body in the fully closing direction.・A double sheep-edge design characterized by installing a small second spring with heavy weight, and drilling a breathing hole in the sleeve and valve casing to communicate the inner space of the sleeve between the first valve valve and the outside air. valves.