JPS6343693B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a main pipe with a main meter and a sub-pipe with a sub-meter, and mainly uses the sub-meter when the flow rate is relatively small and the main meter to measure the flow rate when the flow reaches a large flow rate. Regarding attached water meters.

In general, water meters with auxiliary pipes are equipped with a switching valve on the inlet side of a main meter installed in the main pipe, and a sub-meter is installed on the auxiliary pipe bypassed between the inlet side of the switching valve and the outlet side of the main meter. has been established. The switching valve is configured to close when the flow rate is small and allow tap water to flow only to the sub-meter, and on the other hand, when the flow rate exceeds a predetermined level, it opens due to the water pressure and allows the water to flow to the main meter.

Conventionally, this type of switching valve has specifically had a configuration as shown in FIG. In the figure, 1 is a switching valve storage case, 2 is a filtration member, 3 is a valve box, and 4 is a switching valve storage case.
indicates the valve body. The switching valve storage case 1 has a tap water inlet 1a, a first outlet 1b leading to a sub-meter, and a second outlet 1c leading to a master meter. The valve box 3 is placed via a packing 6 on a support part 5 which is inside the switching valve storage case 1 and is divided into an inlet 1a side and a second outlet 1c side for tap water. The valve box has a cylindrical shape as a whole, and a small diameter part is provided at the lower part of the valve box, and the small diameter part is inserted into a through hole drilled in the support part 5. It is supported by the support part 5. The upper end of the valve box 3 is held down by a holding member 7, and the holding member and the support portion 5
It is fixed between. The filter member 2 is fixed to the lower part of the valve box 3 with screws 8.

Furthermore, a valve body 4 is inserted into the inside of the valve box 3 so as to be movable up and down. The valve body has a cylindrical shape as a whole, and a seat packing 9 is fixed to the lower surface of the valve body with a screw 11 via a presser plate 10, so that it comes into close contact with a stepped valve seat 3b provided at the lower inside of the valve body 3. ing.

Tap water flowing in from the inlet 1a of the switching valve storage case 1 passes through the filtration member 2, and when the flow rate is small, it flows from the first outlet 1b to the secondary meter;
When the flow rate is large, the valve body 4 is pushed up by water pressure, and the flow passes through the plurality of through holes 12 provided on the side surface of the valve box 3 and flows from the second outlet 1c to the main meter.

However, according to a conventional water meter with an auxiliary pipe equipped with such a switching valve, the sudden vertical movement of the valve body 4 causes the valve body 4 to tilt and fit obliquely into the valve box. If the valve body 4 stops moving,
There are many failures in which the valve body and its seat packing 9 are misaligned, and this has the drawback of causing a large drop in instrumental error during switching.

Therefore, an object of the present invention is to provide a water supply with an auxiliary pipe that eliminates such conventional drawbacks, operates the switching valve appropriately and quickly, reduces the drop in instrumental error, and enables accurate flow measurement. The aim is to provide meters.

The gist of the present invention is to provide a main meter provided in a main pipe, a switching valve provided on the outflow side of the main meter, and a sub-pipe between the switching valve and the inflow port side of the main meter. A water meter with an auxiliary pipe is equipped with a secondary meter bypassed by the secondary meter, one end of which is swingably mounted in a switching valve storage case, and the other end is provided with a water receiving portion that receives tap water flowing in through the secondary meter. The present invention further includes a switching valve that opens the valve body in accordance with the pressure of the tap water flowing in through the main meter and limits the inflow of the tap water from the slave meter.

The features of the invention will become more apparent from the following description of the illustrated embodiment.

FIG. 2 is a plan view showing the connected state of the main meter, child meter, and switching valve, and FIG. 3 is a longitudinal sectional view showing the switching valve.

In FIG. 2, reference numeral 20 is a main pipe, and the main pipe has a main meter 22 and a tap water outlet side 22.
A switching valve 24 is provided at a. A sub pipe 26 is connected between the switching valve and the inlet side 22b of the main meter 22.
is bypassed, and a sub-meter 28 is provided in the middle of the sub-pipe. The main meter 22 and the sub-meter 28 shown in FIG. 2 are mainly applied to cases of large flow rate and small flow rate, respectively, and their internal structures are well known and are not shown in the figure.

As shown in FIG. 3, the switching valve 24 consists of a switching valve storage case 30 and a switching valve main body 32 assembled within the case.

The switching valve storage case 30 has an inlet 30a and an outlet 30b for tap water flowing into the interior through the main meter 22. Above the inlet 30a is a secondary pipe 2 that connects the secondary meter 28 and the switching valve 24.
An extraction pipe 36 provided on the switching valve 24 side of No. 6 is attached. At the tip of the extraction pipe, there is a pipe 3 that liquid-tightly penetrates a through hole provided in the switching valve storage case 30 and extends into the switching valve storage case 30.
8 are connected. The pipe has its tip 38
It is bent toward the bottom of the switching valve storage case 30 near a, and is opened at the tip 38a.

The switching valve storage case 30 has a shelf section 42 extending from the inlet port 30a and the outlet port 30b side so as to face each other at a distance of 40 in the center thereof, and the switching valve main body 32 is assembled onto the shelf section. It is being The switching valve body includes a valve seat 44 and a valve body 46. The valve body is connected to the valve seat 4 through the packing 48.
4, and the valve body 46 is attached to the gasket 48 via a presser plate 49 with a set screw 49a. The valve seat 44 is press-fitted into the edge of the step-shaped shelf portion 42 .

The valve body 46 is attached to a mounting portion (not shown) provided on the valve seat 44 at one end 46a. That is, the valve body 46 is swingably attached by inserting a pin 50 into a through hole provided at one end 46a thereof. On the other hand, the other end 46b of the valve body 46 is formed with a convex portion 52 that protrudes toward the tip 38a of the pipe 38, and a water receiving portion 54 is provided on the upper surface of the convex portion. The water receiving portion is a recessed portion having a semicircular cross section, and the radius thereof is at least larger than the diameter of the tip 38a of the pipe 38. The shape of the water receiving portion 54 is not limited to a semicircular cross section as long as the surface is formed into a curved surface.

Next, the operation of the water meter with auxiliary pipe according to the present invention having the above configuration will be explained.

First, when tap water is gradually supplied from the main pipe 20, this tap water passes through the main meter 22 and enters the switching valve 24 from the inlet 30a of the switching valve storage case 30.
At the same time, the inlet side 2 of the main meter 22
Sub-meter 2 via sub-pipe 26 branched from 2a
8 into the switching valve 24 from the pipe 38 as well. Furthermore, the tap water flowing from the secondary meter 28 side through the pipe 38 is jetted from the opening of the tip 38a of the pipe 38 toward the water receiving portion 54 of the valve body 40, as shown by the arrow in the figure. It flows out from the outlet 30a. At this time, since the tap water has a small flow rate, the valve body 46 is moved against the valve seat 46 by its own weight and the pressure from the jet flow from the pipe 38.
closed at the top. Therefore, the tap water in the main meter 22 does not flow, and the impeller (not shown) in the main meter 22 remains stationary. Therefore, the tap water supplied from the main pipe 20 flows only into the secondary meter 28, and only this secondary meter operates, thereby measuring the flow rate.

On the other hand, when the flow rate gradually increases from the main pipe 20 and reaches a predetermined flow rate, a pressure loss occurs in the sub meter 28, and the pressure of the tap water flowing into the switching valve 24 through the main meter 22 increases. This water pressure overcomes the weight of the valve body 46 and the pressure of the jet flow from the pipe 38 and pushes up the valve body 46, whereby the valve body 46 is opened and remains stationary within the main meter 22 and the switching valve 24. Tap water flows and flows out through the inlet 30a and out the outlet 30b. At this time, the tip 38a of the pipe 38 fits into the water receiving portion 54 of the pushed-up valve body 46, thereby restricting the jet of tap water from the secondary meter 28 side. Therefore, in this case, the main meter 22 is activated and the flow rate is thereby measured.
Further, when the valve body 46 is opened due to water pressure during a large flow rate, tap water mainly flows to the main meter 22, but a small amount also flows from the pipe 38.
That is, since the flow also flows to the child meters, the actual flow rate can be measured by summing the numerical values displayed on the indicator of the parent meter 22 and the child meter 28. However, a configuration may be adopted in which the water receiving portion 54 of the valve body 46 completely closes the opening of the pipe 38 and only the main meter 22 is operated. In any case, at high flow rates, the flow from the secondary meter 28 is always restricted by the water receiver 54 of the valve body 46, so at high flow rates, the secondary meter 28 may be overloaded and malfunction. There is no such thing as doing so.

Furthermore, as shown in FIG. 3, since the water receiving portion 54 of the valve body 46 is composed of a concave portion having a semicircular cross section, the jet flow from the secondary meter 28 hits the concave portion at an angle, thereby causing the flat surface to become flat. Compared to the above case, the resistance that the water receiving part 54 receives is extremely small, and a large pressing force can be applied to the opening of the pipe 38, thereby reliably restricting the inflow of tap water from the sub-meter 28. be able to. In this case, as shown in FIG. 4, a cap 56 made of an elastic material is provided at the opening of the pipe 38 to
It is desirable to absorb the impact force caused by the pipe 38 to prevent damage to the opening portion of the pipe 38.

Note that the convex portion 52 provided on the other end 46b of the valve body 46 forms a water receiving portion 54 on its upper surface and acts as a weight for the valve body when the valve body 46 is closed. Since the valve body 46 is provided at a distance from the position where the one end portion 46a of the valve body 46 is supported by the pin 50, the desired weight of the valve body 46 can be ensured, and at the same time, the valve body 46 can be formed small as a whole, thereby reducing costs.

FIG. 5 is a graph showing the instrumental error performance in comparison with a conventional water meter with auxiliary pipes based on the results of experiments conducted using the water meter with auxiliary pipes according to the present invention. As is clear from this graph, while the conventional water meter experiences a drop of about -20% when switching from the child meter to the parent meter, the present invention shows only a slight drop, and its instrumental error performance It turns out that he is excellent.

Therefore, according to the present invention, the switching valve in which the valve body is moved up and down is improved and made into a so-called swing type, so that the flow path can be switched quickly and reliably, and the instrumental error performance can be improved. and thus more accurate flow measurement can be achieved.

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view showing a switching valve in a conventional water meter with auxiliary pipe, Fig. 2 is a plan view showing a water meter with auxiliary pipe according to the present invention, and Fig. 3 is a switching valve shown in Fig. 2. FIG. 4 is a partial sectional view showing the water receiver of the valve body and the tip of the pipe in the present invention, and FIG. 5 shows the instrumental error performance of the present invention in comparison with a conventional water meter with auxiliary pipes. This is a graph showing. 20...Main pipe, 22...Main meter, 24...Switching valve, 26...Sub-pipe, 28...Sub meter, 30...
...Switching valve storage case, 32...Switching valve body, 38
...Pipe, 38a...Pipe tip, 46...Valve body, 46a...One end of the valve body, 46b...Other end of the valve body, 50...Pin, 54...Water receiver.

Claims (1)

[Claims] 1. A master meter installed in the main pipe, a switching valve installed on the outflow side of the main meter, and a secondary meter bypassed via a sub-pipe between the switching valve and the inflow side of the main meter. In the water meter with auxiliary pipe,
The valve body includes a valve body having one end swingably attached to the switching valve storage case and the other end provided with a water receiver against which the tap water flowing in through the main meter hits, and the tap water flowing in through the main meter. A water meter with an auxiliary pipe, comprising the switching valve in which the valve body opens in response to the pressure of the switching valve and limits the inflow of tap water from the secondary meter.