JPS6027777B2 - Direct water supply device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a direct water supply system that dispenses with a water tank installed on the roof of a building or the like and directly supplies water from a water supply source via a pump.

Figure 1 shows a piping diagram of a conventional device of this type, in which 1 is a water tank, 2 is a suction pipe, 3 is a suction side gate valve, and 4 is a piping diagram of a conventional device of this kind.
is a pump, 5 is a check valve, 6 is a discharge side gate valve, 7 is a water supply pipe, 8 is a water supply valve that is closed during the performance test of pump 4 but is normally open, and 9 is a valve in front of the water supply valve. A test tube 10 branched from the water supply pipe is a test valve for opening and closing the test tube 9, which is opened only when testing the performance of the pump 4 and is normally closed.

11 is an overheating prevention orifice with a small hole (not shown) for the pump 4 to flow at a minimum flow rate that does not cause heating, and 12 is an overheating prevention orifice that allows the water that has passed through IJ orifice 1 to flow back to the water receiving tank 1. Prevention piping, 13 is a water demand place (faucet).

With the above structure, if the pump 4 is operated with the discharge side closed, the water circulating in the pump 4 will become high in temperature due to frictional heat, and there is a risk of burning out the packing, bearings, etc.

Therefore, if it is predicted that the amount of water supplied during pump 4 operation will be extremely small, conventionally, for each pump 4, a superheat prevention orifice is installed to flow the minimum flow rate (superheat prevention flow rate) to the pump 4 that will not cause the pump to overheat. 11 were set up. That is, the superheat prevention flow rate that cools each pump 4 is returned to the water tank 1 through the water tank 1 , the suction pipe 2 , the suction side gate valve 3 , the pump 4 , the superheat prevention orifice 11 , and the superheat prevention piping 12 . By the way, in the device configured as above,
Since pump 4 is rarely inspected, test valve 1
The accumulated water in the test tube 9 near 0 rots, which is a disadvantage in terms of hygiene.

Furthermore, since the overheating prevention orifice 11 is provided for each pump 4, there is a drawback that the piping cost increases. The purpose of this invention is to improve the drawbacks of the conventional systems as described above, and provides a direct water supply system in which an overheating prevention orifice is provided in parallel with a test valve that opens and closes a test pipe branching from a water supply pipe. It is something. Below, this invention-
An example will be explained with reference to FIG.

In the figure, the same reference numerals as in FIG. 1 indicate the same or equivalent parts, 14 and 15 are superheat prevention pipes branched from the test pipe 9 on both sides of the test valve 10 and connected to the superheat prevention orifice 11, and 16 and 17 are superheat prevention pipes. This is a gate valve that opens and closes the overheating prevention pipes 14 and 15, and is normally open. Note that when the amount of water used is small, the operation of only one of the pumps 4 is switched, so the superheat prevention flow rate that passes through the superheat prevention orifice 11 may be the same as that of the slave. With the above configuration, when according to the present invention, the superheat prevention flow rate that cools the pump always passes near the test valve and is returned from the test pipe to the water receiving tank via the superheat prevention orifice. Water does not stagnate in the pipes, which is good for hygiene.

In addition, since only one overheating prevention orifice is required and piping costs are also reduced, it is possible to provide an inexpensive and sanitary direct water supply device.

[Brief explanation of the drawing]

FIG. 1 is a piping diagram showing a subordinate example, and FIG. 2 is a piping diagram showing an embodiment of the present invention. In the figures, the same reference numerals indicate the same or corresponding parts, 1
is a water tank, 4 is a pump, 7 is a water supply pipe, 9 is a test pipe, 1
0 is a test valve, and 11 is an overheat prevention orifice. Figure 1 Figure 2

Claims (1)

[Claims] 1. In a direct water supply system that increases the pressure of water supplied from a water supply source using a pump and supplies it via a water supply pipe, a test valve that is always closed except during testing is provided in the test pipe branched from the water supply pipe. Also, a direct water supply device characterized in that an orifice is provided in the test piping on both sides of the test valve in parallel with the test valve to prevent overheating of the pump.