JPH0310400Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a vacuum breaker valve that opens the valve cover using a swing-type vane arm when backflow occurs in a pipe.

[Technical Background and Prior Art] The vacuum breaker valve 35 is installed at the top of a siphon pipe, for example as shown in FIG. It is attached to the top of a siphon pipe 32 that pumps water into a tank 31 located at a certain location. In the case of such piping, water is pumped in the direction of arrow A by the pump 34, and when the pump is stopped, a siphon effect may occur in the piping 32, and water may flow backward from the tank 31 in the direction 30. .
When this backflow occurs, the vacuum breaker valve 35 stops the siphon action by introducing outside air into the pipe to bring the inside of the pipe to atmospheric pressure.

Various vacuum breaker valves have been proposed. For example, the valve shown in Japanese Utility Model Publication No. 43-32028 has a valve stem with a webbed plate and a valve body pivoted on a valve bearing, so that the valve can be opened and closed. Operation is unstable. In response to this, a method has been proposed that improves the instability of valve opening and closing operations. This vacuum breaker valve has a structure as shown in FIG. A valve shaft 42 is inserted so as to be slidable up and down. There is a lid 45 on the top of the valve stem 42.
When the lid is lowered, it seals between it and the seal 46 of the body 43.

A sliding push-up plate 47 is provided below the valve shaft 42, and a cam surface 49 of an arm 48 is in contact with the lower surface of the push-up plate 47. This arm 48 is rotatably supported by a pin 50, and a blade 51 is attached to the lower part of the arm 48.

On the other hand, the tip of the push-up plate 47 pushes up the pin 52, which pushes the pin 54 into the groove of the valve shaft 42 via the cam 53, thereby holding the lid 45 in the open position.

Since the conventional vacuum breaker valve is constructed as described above, when water flows in the forward direction shown by arrow A and pushes the blade 51, and the arm 48 is rotated counterclockwise, the pin of the cam 49 is The height from 50 is reduced and the push-up plate 47 is lowered. In response, the pin 52 is lowered and the pin 54 is pulled out via the cam 53. Then, the lid 45 descends under its own weight together with the valve stem 42, sealing the gap with the seal 46, and opening the pipe 40.
Water can be pumped normally with negative pressure inside.

When a water flow occurs in the direction opposite to arrow A due to the siphon action, the arm 48 rotates clockwise and the height of the cam 49 increases, pushing up the valve shaft 42 via the push-up plate 47 and lifting the lid 45. open. As a result, atmospheric pressure is introduced into the tube 40 through the space between the pin 52 and the partition plate 44, thereby stopping the siphon action. Since the conventional vacuum breaker valve was constructed as described above, the structure was complicated, and the closing operation of the lid 45 was caused by the weight of the lid 45, the valve shaft 42, the cam 53, and the pin 52. Accumulation of foreign matter and water scale easily causes malfunction, and the lid 45 does not close, and air flows between the pin 52 and the partition plate 44.
Since the air is introduced from between the pipes 40 and 40, there is a large inflow resistance, and therefore the siphon action is slow to stop.Furthermore, since the body 43 is screwed into the cylinder 41 formed at the top of the tube 40, it is difficult to adjust the blade arm 51 properly. It is difficult to install it directly facing the flow direction A, and
It had drawbacks such as being troublesome to put on and take off.

On the other hand, regarding the connection structure between the valve shaft and the driving member, Japanese Utility Model Application Publication No. 47-34329 discloses a technology that makes the flow rate adjustment amount of the flow rate regulating valve extremely small in the small flow range and relatively large in the large flow range. Although shown, it cannot be implemented in a swing type vacuum breaker valve. Further, Japanese Utility Model Publication No. 59-31807 discloses a technique for preventing the valve body of a cold-resistant faucet from self-propelling due to its own weight, but it cannot be implemented in a swing-type vacuum breaker valve.

In addition, regarding the normally open biasing means of the valve body,
Publication No. 148163 discloses a technology in which when gas flows at a predetermined flow rate or higher in a gas tank, a valve plate that is biased to the open state presses a spring to close the valve, but the gas pressure is directly applied to the spring. There is a problem with the durability of the spring.

[Purpose of the invention] Therefore, the purpose of the present invention is to provide a vacuum breaker valve that is simple in structure, durable, reliable in operation, and easy to attach to and remove from a pipe body.

[Structure of the invention] According to the invention, there is provided a swing-type blade arm disposed in a pipe and a valve lid that is linked to the blade arm, so that the blade arm is configured to move when backflow occurs in the pipe. A swing-type vacuum breaker valve that opens the valve lid includes a valve body having a flange at the bottom and a boss formed below the flange, which can be attached to and detached from the pipe body by the flange, and has an air circulation window with a large opening area. , a vane arm that is pivotally connected to the boss and is locked in the fully open and fully closed positions by a stopper formed on the boss, and a vane arm that is opened and closed via a pin and is moved in the valve opening direction by a coil spring. It includes a valve stem that is biased and a valve lid provided on the top of the valve stem.

[Operation and effect of the invention] Therefore, since the valve shaft is directly driven by the vane arm via the pin, operation is reliable, and a large amount of air can be smoothly flowed through the air circulation window with a relatively large opening area. Since the siphon is introduced quickly, the siphon action is quickly stopped and backflow is quickly and reliably prevented.

In addition, since the vane arm is locked with a stopper, no impact acts directly on the spring, so
The durability of the coil spring is improved.

In addition, since it is attached to the pipe body with a flange, it is easy to attach and detach it to the correct position.

[Example] Hereinafter, an example of the present invention will be described based on the drawings. FIG. 1 shows the entirety of the vacuum breaker valve of the present invention. The valve is inserted into an opening 17 provided at an appropriate location in a pipe 16, and is closed by a flange-shaped body 8, which is a part of a body 7, which will be described later. It is attached to the tube 16.

The body 8 is provided with a window 18 having a relatively large opening area, and the arm 2 is rotatably supported by a boss 19 projecting downward by a pin 4. A blade 1 is formed on the arm 2 by welding or the like (see FIG. 2), and the blade 1 rotates the arm 2 in response to the water flow flowing through the pipe 16. A long hole 2 formed at the lower end of the valve shaft 6 is connected to the pin 5 at the upper part of the arm 2.
A valve stem is attached by engaging with the valve stem 2, and a lid 11 is fixed to the upper end of the valve stem 6 with a nut. Further, an adjusting nut 13 is placed in the center of the valve shaft 6, and holds a coil spring 12.
This coil spring 12 is always biased in the direction of pushing up the adjustment nut 13, and acts in the direction of opening the lid 11.

On the other hand, a cylindrical body 7 is attached to the upper part of the body 8, and a window 20 having a relatively large opening area is formed in the upper part of the body 7. The valve stem 6 is
It moves up and down guided by bushes 9 and 10 inserted into two bodies 7 and 8, and when the valve stem 6 descends,
The lid 11 will abut the seal 14 and close the window 20. The rotation of arm 2 is controlled by stopper 15,
It is regulated by coming into contact with 21.

Next, the operation of the device of the present invention will be explained.

Figure 3 shows the state immediately after the pump is started, before the water reaches the blade 1. Air pushed by the forward flow flowing in the direction of arrow A enters the body 7 through the window 18 and is pushed up. It is discharged to the outside of the tube 16 through the gap between the lid 11 and the seal 14.

When the normal flow flowing in the direction of arrow A reaches the blade 1 and pushes the blade, the arm 2 rotates counterclockwise as shown in FIG. As a result, the valve stem 6 is pulled down against the coil spring 12, and the lid 11 and the lowered seal 14 are sealed together with the valve stem. As a result, the inside of the pipe 16 becomes a negative pressure, and water is pumped normally.

If the pump is stopped in this state, the water in the pipe 16 will cause a siphon effect, and the water in the pipe will flow to the direction indicated by the arrow B.
There may be cases where the flow flows backwards. In this case, the fifth
As shown in the figure, the blade 1 receives a backflow and rotates the arm 2 clockwise, and the lid 11 is pushed up together with the valve shaft 6 to open a gap between it and the seal 14. This allows a large amount of outside air to be smoothly introduced into the tube 16 through the windows 20, 18 having a relatively large opening area, and the vacuum is quickly broken and the siphon action is quickly stopped. At this time, the blade arm 2 is
1, the impact does not directly act on the coil spring 12.

Even after the water in the tube 16 is discharged, the lid 11 remains open due to the action of the coil spring 12, returning to the state shown in FIG. At this time, the blade arm 2
Since the coil spring 12 is stopped by the stopper 21, no impact acts directly on the coil spring 12. The force of the coil spring 12 is such that when receiving a positive flow, the valve stem 6 and lid 11 descend against the spring, and when the pump is stopped, the position of the adjustment nut 13 is adjusted so that the lid is reliably pushed up. Just adjust it.

[Summary] As explained above, according to the present invention, when backflow occurs due to siphon action, the vacuum state can be quickly broken and the backflow can be stopped.

Furthermore, durability can be improved by preventing impact from directly acting on the coil spring.

Moreover, it can be easily attached and detached to the normal position.

Moreover, complicated structures such as push-up plates and cam surfaces of the prior art can be eliminated.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional side view showing an embodiment of the present invention, Fig. 2 is a view taken in the direction of Fig. Figure 5 is an explanatory diagram showing a state in which a backflow has occurred, Figure 6 is an explanatory diagram showing the installation location of a vacuum breaker valve, and Figure 7 is a cross-sectional side view showing a conventional vacuum breaker valve. It is. 1...Blade, 2...Arm, 4, 5...Pin,
6... Valve stem, 7, 8... Body, 9, 10... Bush, 11... Valve lid, 12... Coil spring, 13... Adjustment nut, 14... Seal, 16
...Tube, 18,20...Air window, 15,21...
Stoppa, 22...Long hole.

Claims (1)

[Scope of utility model registration request] A swing-type vacuum breaker is equipped with a swing-type blade arm placed in the pipeline and a valve lid that is linked to the blade arm, and the blade arm opens the valve lid when a backflow occurs in the pipeline. In the valve, a flange is formed at a lower part, a boss is formed below the flange, the valve body is detachably attached to a pipe body by the flange, and has an air circulation window with a large opening area; A vane arm that is held in the fully open and fully closed positions by a stopper, a valve shaft that is opened and closed via a pin on the vane arm, and is biased in the valve opening direction by a coil spring, and the valve shaft. A swing type vacuum breaker valve characterized by comprising a valve lid provided at the top of the valve.