JPH03597Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention is a line that is installed in a straight line in the fluid circuit of devices and equipment, and allows fluid to pass in only one direction and prevents flow in the opposite direction. Regarding backflow prevention equipment,
In particular, the present invention relates to an adjustment line backflow prevention device that can vary the cracking pressure.

(Prior Art) Conventionally, line backflow prevention devices have been widely used because the flow path is straight, so they can be easily installed in the middle of a pipe.

On the other hand, as this type of line backflow prevention device, an adjustable line backflow prevention device that can vary the cracking pressure is known. That is, the adjustment line backflow prevention device has a stopper 1 on the upstream side, as shown in Figure 2.
9; a cylindrical gland 22 fitted into the casing 20 and having a through hole 21;
A stopper body 23 is fitted into the gland 22 so as to be slidable in the axial direction and is seated against the stopper seat 19, and a ring-shaped adjustment member is screwed into the downstream side of the housing 20 so as to be freely movable in the axial direction. a spring 25 which is interposed between the screw 24 and the stopper 23 and the adjustment screw 24 and biases the stopper 23 to seat the stopper 23 in the stopper seat 19; It is comprised of a ring-shaped lock screw 26 that is screwed into the adjustment screw 24 and comes into contact with the adjustment screw 24. In addition, in the figure, 27 is 0 ring, 2
8 is a front ferrule, 29 is a back ferrule, and 30 is a nut.

In the adjustment line backflow prevention device, when the pressure on the upstream side is smaller than the urging force of the spring 25, the stopper body 23 rests on the stopper seat 19 and blocks the flow path, and the pressure on the upstream side is When the cracking pressure increases and reaches a predetermined cracking pressure, the plug body 23 is pushed downstream and separated from the plug seat 19, and the upstream fluid flows into the through hole 21, gland 22, and each screw 2.
4 and 26 in order and exit to the downstream side. In addition, the cracking pressure is adjusted using adjustment screw 2.
4 and the lock screw 26 in the axial direction.

However, in the adjustment line backflow prevention device, even if the cracking pressure is set to a predetermined value, if the device is subjected to some kind of vibration or time passes, the lock screw 26 will loosen and the adjustment will be difficult. There was a problem that the screw 24 moved a certain amount and the biasing force of the spring 25 changed, causing the cracking pressure to fluctuate. In this case, other devices and equipment will be adversely affected.

(Problem to be solved by the invention) The present invention was devised to solve the above problem, and its purpose is to make an adjustment that can reliably prevent changes in the biasing force of the spring set to a predetermined value. To provide line backflow prevention equipment for use.

(Means for Solving the Problems) The adjustment line backflow prevention device of the present invention has a cylindrical casing with a stopper on the upstream side, and a cylindrical case that is movable in the axial direction inside the casing. A stopper body that is unseated,
An adjustment screw screwed into the downstream side of the casing, a spring interposed between the stopper and the adjustment screw to bias the stopper to the stopper, and a casing located downstream of the adjustment screw. An adjustment line backflow prevention device consisting of a locking screw screwed into the body is characterized in that an elastic body is interposed between the adjusting screw and the locking screw to urge them apart.

(Function) In the adjustment line backflow prevention device, when the pressure on the upstream side is smaller than the urging force of the spring, the plug body rests against the stopper seat and blocks the flow path, and the pressure on the upstream side becomes high. When a predetermined cracking pressure is reached, the plug body is pushed downstream against the urging force of the spring and separated from the stopper seat, and the fluid on the upstream side passes through the flow path in the housing to the downstream side. go.

Furthermore, since an elastic body is inserted between the adjustment screw that supports one end of the spring and the lock screw that prevents the movement of the spring to keep them apart, both screws will not loosen and move. . As a result, the biasing force of the spring does not change, and fluctuations in cracking pressure can be prevented.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 1 is a vertical cross-sectional view of an adjustment line backflow prevention device showing an embodiment of the present invention in a fully closed state, in which 1 is a housing, 2 is a stopper, 3 is an adjustment screw, 4 is a spring, and 5 is a The lock screw 6 is an elastic body.

The housing 1 consists of a cylindrical male main body 7 and a cylindrical female main body 8 screwed onto one side of the male main body 7. A stopper seat 9 is formed. Other pipes (not shown) are connected to both ends of the housing 1, respectively.

The stopper body 2 is provided in the housing 1 so as to be freely movable in the axial direction so as to be seated on and removed from the stopper seat 9. That is, in this embodiment, the stopper 2 has a substantially cylindrical shape with the upstream side closed, and the O-ring 10 is fitted on the upstream side, so that the O-ring 10 comes into contact with the stopper seat 9. It is fitted into a cylindrical gland 11 fitted into the male main body 7 so as to be slidable in the axial direction. Note that a space S is formed between the outer circumferential wall of the gland 11 on the upstream side from the intermediate part and the inner circumferential surface of the male main body 7,
The upstream outer circumferential wall and the intermediate outer circumferential wall of the gland 11 are provided with a first wall that communicates between the space S and the inside of the gland 11.
A through hole 12 and a second through hole 13 are formed respectively. Further, the plug body 2 is configured to reciprocate on the upstream side of the second through hole 13, and when it touches the stopper seat 9, it closes the first through hole 12 and is spaced a certain distance from the stopper seat 9. At times, the first through hole 12 is left open.

The adjustment screw 3 is screwed into the downstream side of the housing 1, that is, inside the female main body 8, so as to be movable in the axial direction, and a hexagonal square hole 14 is bored in the center thereof.

The spring 4 is interposed between the stopper 2 and the adjustment screw 3 and always biases the stopper 2 so as to be seated on the stopper seat 9, and the urging force moves the adjustment screw 3 in the axial direction. It is adjusted by

The lock screw 5 is screwed into the housing 1 on the downstream side of the adjustment screw 3, that is, inside the female body 8, so as to be movable in the axial direction, and has the same hexagonal corner as the adjustment screw 3 in the center. A hole 15 is bored.

An elastic body 6 is interposed between the adjustment screw 3 and the lock screw 5 to urge them apart, and in this embodiment, a disk spring is used as the elastic body 6.

In FIG. 1, 16 is a front ferrule, 17 is a back ferrule, and 18 is a nut.

Next, the operation of the adjustment line backflow prevention device will be explained.

When the pressure on the upstream side is smaller than the urging force of the spring 4, the stopper body 2 abuts against the stopper seat 9 and blocks the flow path.

When the pressure on the upstream side increases and reaches a predetermined cracking pressure, the plug body 2 is pushed downstream against the urging force of the spring 4 and is removed from the stopper seat 9.

Then, the plug body 2 is connected to the first through hole 12 of the gland 11.
When pushed to the opening position, the fluid on the upstream side flows through the gap between the stopper seat 9 and the stopper body 2, the first through hole 12, the space S,
It sequentially passes through the second through hole 13, the inside of the gland 11, and the square holes 14 and 15 of each screw 3 and 5, and exits to the downstream side.

In addition, when changing the biasing force of the spring 4, remove the female mold body 8 side from the piping, insert a hexagonal wrench into the square holes 14 and 15 of each screw 3 and 5 from the downstream side of the female mold body 8, and The screws 3 and 5 may be rotated in forward and reverse directions to move them in the axial direction.

In the above embodiment, a disc spring was used as the elastic body 6, but the elastic body 6 is not limited to the above embodiment, and may be used to bias the adjustment screw 3 and the lock screw 5 in the direction of separating them. It's good to have. For example, a compression spring may be used.

Further, in the above embodiment, the cylindrical gland 11 was fitted into the casing 1, and the cylindrical plug 2 with one end closed was inserted into the gland 11. This is not limited to the embodiment, and when the stopper 2 hits the stopper seat 9, the flow path is blocked, and when the stopper 2 leaves the stopper seat 9, the upstream side and the downstream side of the housing 1 communicate with each other. Then, the shape of the plug 2 and the plug 2
The configuration in which the is housed in the housing 1 is arbitrary.

Furthermore, the configuration and shape of the casing 1 are not limited to the above embodiments.

(Effects of the invention) As described above, the adjustment line backflow prevention device of the invention has an elastic force between the adjustment screw that supports one end of the spring and the lock screw that prevents the movement of the spring so as to separate both screws. Because the body is interposed, even if the device is subjected to some kind of vibration or time passes, each screw will remain in good contact with the inside of the housing due to the force of the elastic body, and will not move from its set position. do not have. As a result, if the biasing force of the spring changes and the cracking pressure fluctuates during use of the device, this will not be transmitted and will not adversely affect other devices or devices installed in the fluid circuit.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view of an adjustment line backflow prevention device according to an embodiment of the present invention in a fully closed state, and FIG. 2 is a vertical sectional view of a conventional adjustment line backflow prevention device in a fully closed state. 1 is a housing, 2 is a stopper body, 3 is an adjustment screw, 4 is a spring, 5 is a lock screw, 6 is an elastic body, and 9 is a stopper seat.

Claims (1)

[Scope of utility model registration request] A cylindrical housing 1 having a stopper seat 9 on the upstream side, a stopper body 2 provided movably in the axial direction within the housing 1 and seated against the stopper seat 9, and a downstream side inside the housing 1. A spring 4 is provided between the adjustment screw 3 screwed into the stopper 3, a spring 4 is provided between the stopper 2 and the adjustment screw 3, and urges the stopper 2 to be seated in the stopper seat 9; In an adjustment line backflow prevention device consisting of a lock screw 5 screwed into a housing 1, an elastic body 6 is interposed between the adjustment screw 3 and the lock screw 5 to urge them apart. An adjustment line backflow prevention device characterized by: