JPH0514832B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a check valve, and more particularly to a composite check valve equipped with a flow switch for detecting the flow of fluid.

[Technical background of the invention and its problems]

In water supply systems that supply water from a water supply pump to designated locations, a check valve is used to prevent the pump from reversing when the pump stops, such as during a power outage. Depending on the nature of the water, water hammer may occur in the water supply system. Therefore, in order to reduce this water hammer, a check valve that performs a quick closing operation using a spring or the like, for example, a check valve of a stop valve type, is used. In addition, in a typical water supply system, a flow switch is used to detect the flow in the water supply pipe and accurately control the amount of water fed.

However, such check valves and flow switches have conventionally been installed separately in the water supply pipes, resulting in a narrow piping space and increased costs.

[Object of the Invention] The present invention has been made in consideration of the above points, and provides a flow valve type checker having a flow switch function that detects the flow in a water supply pipe and controls the amount of water supplied. The purpose is to provide a valve.

[Summary of the invention]

The present invention provides a hollow casing having a fluid inlet, an outlet, and a flow path that communicates the inlet and the outlet and has a valve seat formed in the middle, and a hollow casing that has the valve seat in the casing. A pair of stop valves that are swingably disposed so as to abut and close, a spring that presses the pair of stop valves toward the valve seat, and a spring that passes through one of the pair of stop valves. a small port provided in the valve, a swing pin fixed to a side of the casing of the one valve facing the outlet, and a swing pin swingably attached to the swing pin to open and close the small port. a small flapper, a small spring that presses the small flapper toward the small port, and close to at least one of the pair of flap valves;
a detection switch for a stop valve provided at a position to detect a predetermined large flow rate based on the swing motion of the stop valve; This is a check valve type check valve having a detection switch for a small flapper provided at a position for detecting a small flow rate.

According to the present invention, a small flow rate is reliably detected by the rocking motion of the small flapper, and a large flow rate is reliably detected by the rocking motion of the pair of flap valves, and a control signal for the water supply system is obtained. The valve and small flap can quickly close the inlet, prevent backflow in the pipeline, and effectively reduce water hammer. Furthermore, since the check valve and flow switch do not have to be disposed separately and independently, the piping space does not become narrow.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

The figure is a cross-sectional view showing an embodiment of the check valve type check valve according to the present invention.

In the figure, reference numeral 11 indicates fluid inlet ports 1 at both ends.
3 and an outlet 15, and a flow path 15 is formed in the hollow casing 11 to communicate the inlet 13 and the outlet 15. A valve seat 17 formed to protrude from the inner wall of the casing 11 is provided in the flow passage 14, and a pair of valves 19a and 19b are arranged so as to abut on this valve seat 17. The pair of stop valves 19a and 19b are in close contact with the valve seat 17 so as to be able to completely cut off the flow passage 14.
A swing shaft 21 is disposed approximately in the center of the casing 11, with both ends rotatably supported by the casing 11. The portion is inserted and held so as to be swingable. A spring 23 is disposed on the swing shaft 21 so as to come into contact with the side facing the outlet 15 of the pair of valves 19a, 19b. This spring 23 is connected to a pair of valves 19.
a, 19b toward the valve seat 17.

One of the pair of valves 19a and 19b, for example 19a, has a small port 25 with a small diameter.
is provided so as to penetrate through the stop valve 19a.
Further, a small valve seat 27 is formed at the end of the small port 25 on the outflow port 15 side. A small flapper 29 that closes the small port 25 in close contact with the small valve seat 27 is swingably disposed on the outflow port 15 side of the stop valve 19a. Kofratsupa 29 is
A swing pin 31 whose end on the center side in the casing 11 is fixed to the outlet 15 side of the stop valve 19a.
The pivot pin 3 is rotatably inserted and held in the
A small spring 33 wound around the small valve seat 2
It is being pushed towards 7. small flatspa 29
A magnet 35 is attached to the end of the inner wall surface of the casing 11, and a small flap detection switch, such as a reed switch 37, which is activated by the swinging motion of the magnet 35, is attached to the magnet 35.
is located close to. A magnet 39 is attached to the end of the inner wall surface of the casing 11 of the other of the pair of valves 19a and 19b, and a detection switch for the valve is operated by the swinging motion of the magnet 39. For example, a reed switch 41 is disposed close to the magnet 39. The attachment point of the reed switch 41 can be adjusted and moved in the vertical direction.

Next, the operation of this embodiment having such a configuration will be explained.

First, when a small flow rate flows in the water supply system, water is forced into the inlet 13 by the water supply pump, and when it enters the casing 11, the energy of the water pushes the small flapper 29, causing it to swing by an angle corresponding to the flow rate. . This swinging motion of the small flapper 29 causes the magnet 35 to open the reed switch 37. If the swing angle of the small flapper 29 and its flow rate when the reed switch 37 is opened are predetermined, it is possible to detect that water is being supplied to the water supply system and its flow rate by the opening operation of the reed switch 37. be done. In this case, since the pair of valves 19a and 19b are closed, the flow area becomes very small, and small flow rates can be detected accurately. When the amount of water supplied increases further, the pair of valves 19a and 19b also swing according to the flow rate.
This swinging motion of the pair of stop valves 19a, 19b causes the reed switch 41 to be opened by the magnet 39 attached to the stop valve 19b.
By predetermining the swing angle of the pair of valves and the flow rate when the reed switch 41 is opened, a predetermined flow rate can be detected by the opening operation of the reed switch 41. Further, since the mounting position of the reed switch 41 can be changed, the flow rate for opening the reed switch 41 can be arbitrarily determined. In this way, the predetermined flow rate in the case of a small flow rate and the predetermined flow rate in the case of a large flow rate can be accurately detected, so when the demand for water decreases and the small flapper 29 no longer swings, , you can stop pump operation or change the operating status of other pumps. Next, when the demand for water increases and the small flapper 29 swings to open the reed switch 37, the number of pumps in operation can be increased or the operating conditions of other pumps can be changed. When the demand for water further increases and the pair of stop valves begin to swing, and the flow rate exceeds a predetermined large flow rate, the reed switch 41 opens, so in this case it is possible to increase the number of pumps in operation. In this way, it is possible to accurately detect a predetermined small flow rate and a predetermined large flow rate and control the number of pumps in operation, thereby improving the durability of the pump and reducing running costs.

Next, when the pump stops due to a power outage, etc., the pair of stop valves 19a, 19b and the small flapper 29 perform a rapid closing operation due to the repulsive force of the spring 23 and the small spring 33, preventing backflow in the pipe. The flow path 14 is completely severed before it occurs. This quick closing action effectively reduces water hammer. In this case, the swing of the small flapper 29 in the closing direction closes the reed switch 35, generates a pump stop signal, and activates the pump brake to prevent the pump from reversing.

In this embodiment, an example is shown in which the detection switch is a reed switch that operates according to the movement of the magnet, but the detection switch is not limited to this.
For example, the structure may be such that the movement of a pair of stop valves and a small flapper is detected by a proximity switch.

In addition, for both small and large flow rates, the detected flow rate is determined by the size of the inlet, the strength of the spring, the weight of the pair of flap valves or small flaps, the position of the reed switch, etc., but these can be adjusted as desired. Can be adjusted freely.

Furthermore, in order to detect the rocking motion of a pair of stop valves and a small flapper, an example is shown in which one reed switch is provided for each, but the invention is not limited to this.
A plurality of reed switches may be provided for each.
By providing a plurality of reed switches, a plurality of predetermined flow rates can be detected for both large and small flow rates, and the number of operating pumps can be controlled more effectively.

〔Effect of the invention〕

As explained above, according to the present invention, a predetermined small flow rate can be accurately determined from the swinging motion of the small flapper using the small flapper detection switch when the stop valve is in the closed position. Further, by using the detection switch for the stop valve, a predetermined large flow rate can be determined from the swinging motion of the stop valve. This makes it possible to efficiently control the number of water pumps in operation. Furthermore, when the pump is stopped, the inlet is quickly closed, preventing backflow in the water supply pipe, and effectively reducing water hammer. It also functions as a flow switch and check valve.
Since it can be performed by one device, there is no need to install it separately as in the past. Therefore, the piping space does not become narrow, and the cost of the piping system can be reduced. Furthermore, since the number of members in the pipe is reduced, pressure loss can be reduced.

[Brief explanation of the drawing]

The figure is a cross-sectional view showing an embodiment of the check valve type check valve according to the present invention. 11...Casing, 13...Inflow port, 14...
...Flow path, 15... Outlet, 17... Valve seat, 19
a, 19b...Chiyo valve, 21...Swing shaft, 23
... Spring, 25 ... Small port, 27 ... Small valve seat, 29 ... Small flap, 31 ... Swing pin,
33...Small spring, 35...Magnet, 3
7...Reed switch, 39...Magnet, 4
1...Reed switch.

Claims (1)

[Scope of Claims] 1. A hollow casing having a fluid inlet, an outlet, and a flow path that communicates the inlet and the outlet and has a valve seat formed in the middle; a pair of stop valves that are swingably disposed so as to abut and close the valve seats; a spring that presses the pair of stop valves toward the valve seat;
a small port provided through one of the pair of control valves; a swing pin fixed to the side of the one control valve facing the outlet of the casing; a small flapper swingably attached to the swing pin so as to open and close; a small spring that presses the small flapper toward the small port; and a small flap located close to at least one of the pair of swing valves; a detection switch for a stop valve provided at a position that detects a predetermined large flow rate based on the swing motion of the stop valve; A check valve having a detection switch for a small flapper installed at a position for detecting a small flow rate. 2. The check valve according to claim 1, wherein the detection switch is a reed switch operated by the movement of a magnet.