JPS6222708Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a constant flow valve that supplies a predetermined flow rate to the outlet side even if a change occurs in the differential pressure between the primary pressure on the inflow side and the secondary pressure on the outflow side.

Conventionally, in the case of constant flow valves that combine a valve body and a flow contracting pipe, the valve body is attached directly to the spring, so the valve body often vibrates violently due to changes in flow, and the spring is directly attached to the fluid. Since the springs are installed in the flow of air, dirt and other substances may adhere to the springs and vibrations may occur, causing problems with accuracy.

This design has a coil spring and a piston shaft built into the cylinder, and is attached to the outside of the valve body of the piston shaft, and the cylinder is installed in the cylindrical pipe, so that the force generated by the differential pressure acts only on the valve body. The structure is such that the valve body 6 is moved when the primary pressure, secondary pressure, or both of them fluctuate in the case of a fluid, or when either the primary pressure or the secondary pressure fluctuates in the case of a gas. If the valve body moves in the axial direction,
To provide a highly accurate constant flow valve that can always obtain a constant flow rate.

Next, a specific embodiment of this invention will be described with reference to the drawings. That is, in this case, one side is the open end 1.
A valve shaft 4 passes through a cylinder 3 with the other end being a closed end 2, and a piston 5 serving as a damper is provided at one end of the valve shaft 4 located inside the cylinder 3.
A valve body 6 is fixed to the other end of the valve shaft 4 located outside the cylinder 3, and a coil spring 7 is inserted through the valve shaft 4 and interposed between the piston 5 and the closed end 2 to open the cylinder 3. The end 1 of the arm plate 8 is covered with a strainer 13, and the end of the arm plate 8, which is integrally fixed radially to the outer edge of the cylinder, is fixed to the inner wall of the cylindrical tube 9. This is a constant flow valve in which a flow contraction tube 11 having an inner diameter contour portion 10 designed to allow a predetermined constant flow rate to flow even if the flow rate changes is disposed opposite to the valve body 6.

According to this invention, an inflow pipe and an outflow pipe are connected to both ends of the cylindrical pipe 9, and when a pressurized fluid flows in, the fluid W flows from the inflow pipe through the passage 14 between the cylinder 3 and the cylindrical pipe 9, and is further compressed. It passes through the flow tube 11 and is discharged from the outlet tube. At this time, the pressure fluid is contracted between the valve body 6 and the flow contraction tube 11, and a pressure difference is generated between the front and rear portions of the valve body 6. Therefore, the valve body 6 receives the force generated by the differential pressure, compresses the coil spring 7, moves downstream, forms a required orifice hole area 15 with the flow contraction pipe 11, and is in equilibrium. Now, if higher pressure fluid flows in or the pressure of the fluid on the outflow side decreases, the differential pressure across the valve body 6 will increase.
The valve body 6 moves downstream while compressing the coil spring 7 built into the cylinder 3 together with the valve shaft 4 and the piston 5, and the orifice hole area 1 between the valve body 6 and the contracting pipe 11 is compressed.
Reduce and balance 5. Conversely, when the pressure of the inflowing fluid decreases or the pressure of the fluid on the outflow side increases, the differential pressure across the valve body 6 decreases, causing the coil spring to expand, causing the valve body 6 to move between the valve shaft 4 and the piston. 5, the orifice hole area 15 is expanded and balanced. In this way, the valve body 6, the valve shaft 4, and the piston 5 also move according to changes in fluid pressure, and at this time, the coil spring 7 is restrained between the inner wall of the cylinder 3 and the closed end 2 and the piston 5. Expand and contract. In addition, the inner diameter contour portion 10 of the contraction tube 11 is
In combination with the valve body 6, the flow rate remains a predetermined constant flow rate even if either the primary pressure or the secondary pressure or both of the liquids or the primary pressure or the secondary pressure of the gases fluctuates in combination with the valve body 6. Since it is formed by such a curve, a constant flow rate can always be obtained from the outflow pipe in response to pressure changes on the inflow side and the outflow side.

Further, according to the present invention, the open end 1 of the cylinder 3 is covered with a strainer 13, and the piston 5 and the cylinder 3
The sliding part between the valve shaft 4 and the cylinder closing end 2
This prevents dust from entering the sliding part between the valve body 6 and the valve element 6, which allows the valve element 6 to operate smoothly. Also, piston 5
Since the cylinder 3 and the cylinder 3 form a damper, even if a sudden pressure change occurs, the valve shaft 4, that is, the valve body 6
It is possible to maintain smooth fluid flow without causing hunting. And cylinder 3,
The valve shaft 4, piston 5, valve body 6, spring 7, strainer 13, etc. are integrally assembled, and this series is integrally fixed to the cylinder 3.The end of the arm plate 8 is provided on the inner wall of the cylindrical pipe 9. Since the structure is such that the snap spring 12 is simply fitted into the groove and installed, installation is extremely easy. Therefore, by removing and installing the snap spring 12, the main operating parts can be easily installed together with the cylinder 3.
Since it can be removed, maintenance and assembly are easy, and there are fewer parts, making it highly productive and durable.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view, and FIG. 2 is a side view. Symbols in the figure: 3...Cylinder, 4...Valve shaft, 5...
...Piston, 6...Valve body, 7...Coil spring, 8
... Arm plate, 9 ... Cylinder tube, 10 ... Inner diameter contour part, 1
1... Contraction pipe, 13... Strainer, 14... Passage, 15... Orifice hole area.

Claims (1)

[Scope of utility model registration request] A radial arm plate 8 is fixed to the peripheral wall of a cylinder 3 whose one open end 1 is covered with a strainer 13 and the other end is a closed end 2, and the end of the arm plate 8 is a step provided on the inner wall of the cylindrical pipe 9. The cylinder 3 is fitted into the cylindrical pipe 9 by abutting on the groove and the snap spring 12 is fitted, and the piston 5 is fixed to one end of the valve shaft 4 passing through the cylinder 3. 4, and a coil spring 7 is provided between the piston 5 and the closed end 2 of the cylinder 3.
is inserted into the valve shaft 4 and interposed therein, and the inner diameter contour portion 10 is designed to allow a predetermined constant flow rate to flow even if the pressure on the front and rear surfaces of the valve body 6 changes at the other end of the cylindrical pipe 9. A constant flow valve in which a flow contraction pipe 11 having a flow contraction tube 11 is disposed opposite to a valve body 6.