JPH0449021B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates primarily to a gas proportional control valve for use in gas instantaneous water heaters.

Gas instantaneous water heaters, which are widely used in ordinary homes, do not have a hot water storage tank, and the hot water temperature is controlled by the amount of gas burned (supplied) rather than by a thermostat. This is done by changing the flow rate or by changing the flow rate of hot water, and from this, when the flow rate of hot water is changed, the hot water temperature changes accordingly, and this point is the gas instantaneous. This is the biggest drawback of water heaters.

This means that even if you try to control the amount of gas supplied, which is the amount of gas combusted, by operating a gas control valve installed in the gas supply path by incorporating a thermostat and sensing the outlet temperature, the thermostat will not work. Control of gas supply amount by Tatsuto changes the flow rate of hot water →
This is done through the following steps: change in hot water temperature → thermostat sensing operation → control of gas supply amount, so when changing the hot water flow rate, the gas supply amount is changed in response to the hot water flow rate. This is due to the fact that it was considered impossible to control using a mechanical method, as the operation could not be done in time and the control would be incomplete.

For this reason, in recent years, methods have been developed to electronically sense the tapped water temperature and proportionally control the amount of gas burned based on this information, thereby keeping the tapped water temperature approximately constant even when the tapped water flow rate is changed. being developed.
However, this method has a problem in that the mechanism is complicated and expensive due to the electronic control method using a microcomputer.

The present invention has been made in order to solve these problems, and it is possible to maintain the hot water temperature of a gas instantaneous water heater at a substantially constant level even if the hot water output amount changes by mechanical control. The object of the present invention is to provide a gas proportional control valve.

The present invention has been completed based on the knowledge obtained as a result of various experiments and studies in order to solve the above-mentioned problems.

In other words, when controlling the gas supply amount to control the hot water temperature, it is not possible to simply control the gas supply amount by operating the gas control valve with a thermostat that senses the hot water temperature and operates. The response speed to changes in the hot water temperature is slow, and the control to change the amount of gas combustion in response to changes in the hot water temperature due to changes in the hot water flow rate cannot be done in time. A gas control valve that controls the gas supply amount first roughly controls the gas supply amount according to changes in the tapping flow rate, and then the controlled gas supply amount is controlled by the gas supply amount. If the temperature of hot water boiled up by a combustion-operated gas burner is sensed and corrected by a thermostat that operates, the amount of gas supplied will change immediately in response to changes in the flow rate of hot water, and the gas supply will be adjusted accordingly. It has become possible to accurately control the amount of hot water to maintain the tapped water temperature at a predetermined temperature, and the amount of gas burnt can be controlled proportionally in response to changes in the hot water flow rate, and the control to maintain the tapped hot water temperature approximately constant has become sufficient. This is because the result was that it became possible to do so.

Therefore, in the present invention, a hot water flow path connected to a hot water supply pipe and a gas supply path connected to a gas pipe are provided in the main body so as to be adjacent and parallel, and in the gas supply path, A partition wall is provided that partitions the primary side communicating with the gas piping side and the secondary side communicating with the gas burner, and the partition wall includes a first valve port and a second gas control valve whose opening and closing are controlled by the first gas control valve. A second valve port, which is opened and closed by The operation of the thermoelement piston is linked to a first gas control valve provided in the gas supply path via a rod, and the operation of the piston of the thermoelement is linked to a second control valve provided in the gas supply path. This paper proposes a gas proportional control valve in an instantaneous water heater.

Next, an example of implementation will be described in detail with reference to the drawings.

In FIG. 1, a indicates the main body of the gas proportional control valve A according to the present invention, 1 indicates a flow path for hot water provided in the main body a, and 2 indicates a gas supply path. Further, b indicates a conduit that leads hot water from a heat exchanger of a gas instantaneous water heater (omitted in the drawing), and is connected to a connection port 10 on the inlet side of the hot water flow path 1. . Further, c is a hot water pipe that guides the hot water flowing into the hot water flow path 1 to the hot water tap (faucet), and d is a gas pipe that leads gas from the gas main tap to the connection port 20 on the inlet side of the gas hot water feed path 2. ,
Reference character e indicates a gas pipe for supplying the gas supplied to the gas supply path 2 to the gas burner of the gas instantaneous water heater.

The hot water flow path 1 has an end on the outlet 11 side connected to the hot water supply pipe c bent upward to form a vertical cylindrical portion 1a. A through hole 12 passing vertically is formed in a portion of the cylindrical portion 1a that overlaps with the axis. In the cylindrical portion 1a, a piston-shaped actuating body 3 (or differential pressure plate) is provided with a through hole 30 penetrating vertically.
is fitted so as to be slidable up and down while keeping the space between its circumferential surface and the inner wall of the cylindrical portion 1a substantially watertight, and is interposed between the spring receiving seat 31 provided in the cylindrical portion 1a. It is urged downward by a spring 32. Further, a rod 33 whose upper end is connected to the aforementioned actuating body 3 is fitted into the through hole 12 so as to be able to slide up and down, and the lower half of the rod 33 is made to protrude below the hot water flow path 1. There is.

The gas supply path 2 is disposed below the hot water flow path 1, and there is a gas pipe d inside it.
A partition wall 21 is provided to partition a primary side 2a that communicates with the gas burner and a secondary side 2b that communicates with the gas burner. A first gas control valve 4 that moves up and down to control the opening and closing of the first valve port 40 is biased toward the open side by a spring 41 and corresponds to the first valve port 40 . The lower end side of the rod 33 connected to the actuating body 3 so as to protrude downward from the actuating body 3 is inserted into the gas supply passage 2 through a through hole provided in the upper wall of the gas supply passage 2. Rushing into
This is connected to the first gas control valve 4, thereby increasing the flow path of the hot water flowing in the hot water flow path 1, and increasing the resistance of the hot water flowing through the through hole 30 of the actuating body 3. When the actuating body 3 moves upward against the bias of the spring 32, the first gas control valve 4 provided in the gas supply path 2 moves to increase the opening degree of the first valve port 40, and the gas is The amount of gas supplied to the burner is increased.

Reference numeral 5 denotes a thermoelement disposed in the hot water flow path 1, which pushes out a piston 52 provided in a guide cylinder portion 51 when the wax sealed in the body 50 expands due to rising temperature. It is a well-known wax thermo-element, and its guide cylinder part 51 is fitted into a through hole provided in the lower wall of the hot water flow path 1 so as to be slidable up and down while maintaining watertightness. A piston 52 for moving in and out is made to protrude below the hot water flow path 1, and the upper end of the body 50 located in the hot water flow path 1 is screwed into the upper wall of the hot water flow path 1. It is supported by a spring 53 provided between them.

7 is a second gas control valve installed in the gas supply path 2 separately from the first gas control valve 4 to control the gas supply amount by the operation of the thermoelement 5;
The partition wall 21 is provided in correspondence with a second valve port 70 provided separately from the first valve port 40, and is biased by a spring 71 so as to push the second valve port 70 toward the opening side. The lower end of a connecting rod 72 is connected to the upper surface side of the second gas control valve 7 and can be fitted onto the upper wall of the gas supply path 2 so as to slide up and down while maintaining airtightness. The upper end is connected to the protruding end of the piston 52 of the thermoelement 5 described above, so that the opening degree of the valve port 70 is controlled by the sensing operation of the outlet hot water temperature of the thermoelement 5. Note that 54 is a return spring for the thermoelement 5, and the spring 53 is a relief spring. In FIG. 1, f is a solenoid valve provided in the gas pipe d, and g is controlled to open when water flows into the heat exchanger by the operation of a flow switch provided in front of the heat exchanger; is a pipe that leads gas to the pilot burner p, h is a solenoid valve installed in the gas pipe d and controlled to be kept open by a thermocouple when the pilot burner p is performing combustion operation, and i is a main valve. shows.

The embodiment device constructed in this manner operates as follows.

When the hot water tap (faucet) equipped with the hot water supply pipe c is opened, hot water flowing from the heat exchanger of the gas instantaneous water heater into the hot water flow path 1 via the conduit b is transferred to the thermoelement 5 and the operating body. It flows out from the faucet after 3 steps.

As a result, the actuating body 3 provided in the hot water flow path 1 moves upward due to the differential pressure generated between the upper surface side and the lower surface side as the hot water flows in the hot water flow path 1. The gas control valve 4 is pulled up to open the first valve port 40, and the thermoelement 5 moves the second gas control valve 7 according to the temperature of the flowing hot water. Assume that this results in the state shown in FIG.

Next, from this state, if you squeeze the faucet and change the amount of hot water that comes out, the resistance of the hot water passing through the through holes 30 of the actuating body 3 will decrease, and the resistance between the upper and lower surfaces of the actuating body 3 will decrease. As the differential pressure becomes smaller, the actuating body 3 is actuated to move downward by the pressure of the spring 32, pushing down the first gas control valve 4, and opening the first valve port 40 as shown in FIG. Reduce the opening and reduce the amount of gas supplied to the gas burner of the gas instantaneous water heater.

Then, the hot water heated by the gas burner that operates while the gas supply amount is restricted by the above-mentioned operation flows into the hot water flow path 1.
It comes into contact with the thermoelement 5. At this time, if the temperature of the hot water is lower than the desired temperature set by the adjustment screw 6, the thermoelement 5
As the pressure to push out the piston 52 decreases,
The piston 52 is pushed in by the return spring 54,
As shown in FIG. 2, the second gas control valve 7 moves to widen the opening degree of the second valve port 70, increasing the amount of gas supplied and raising the temperature of the hot water. Try to keep the temperature almost constant.

In addition, if the faucet is widened to increase the amount of hot water coming out from the above-mentioned state, the increase in the amount of hot water flowing into the hot water flow path 1 will increase the differential pressure between the top and bottom of the actuating body 3. The body 3 is pushed up against the pressure of the spring 32 as shown by the chain line in FIG. 2, and operates to pull up the first gas control valve 4 as shown by the chain line in FIG. 40 to increase the amount of gas supplied. Then, the boiled hot water flows into the hot water flow path 1 in a state where the combustion operation is active due to the large amount of gas supplied, and comes into contact with the thermoelement 5.
The amount of gas supplied is adjusted by the operation of , and the hot water temperature is maintained at the set temperature.

As explained above, the gas proportional control valve in the gas instantaneous water heater according to the present invention has an operating body 3 that senses the flow rate and operates when the amount of hot water output is changed.
By controlling the first gas control valve 4 by
First, the amount of gas supplied is changed on the fly, and then the thermostat is activated by sensing the temperature of the water that is boiled up by the gas burner that burns with that amount of gas supplied. element 5
Since this is corrected by controlling the second gas control valve 7, this effectively eliminates the problem of response delay when changing the amount of hot water and maintains the desired hot water temperature. A gas proportional control valve in a gas instantaneous water heater is obtained which can maintain a set temperature set at .

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view of a gas proportional control valve in a gas instantaneous water heater in which the present invention can be implemented, and FIG. 2 is an explanatory view of the same operation. Explanation of drawing symbols, A...Gas proportional control valve, a...
...Main body, b...Conduit, c...Hot water piping, d...Gas piping, e...Gas pipe, f...Solenoid valve, g...Pipeline, h...Solenoid valve, i...Main valve, p ...Pilot burner, 1...Hot water flow path, 1a...Cylinder part, 1
0...Connection port, 11...Outlet, 12...Through hole, 2
... Gas supply path, 2a ... Primary side, 2b ... Secondary side, 20 ... Connection port, 21 ... Partition wall, 3 ... Actuating body, 30 ... Through hole, 31 ... Spring seat, 32 ……
Spring, 33... Rod, 4... Gas control valve, 40
... Valve port, 41 ... Spring, 5 ... Thermoelement, 50 ... Body, 51 ... Guide tube section, 52
...Piston, 53...Spring, 54...Return spring,
6...Temperature adjustment screw, 7...Gas control valve, 70...
...Valve port, 71...Spring, 72...Connection rod.

Claims (1)

[Claims] 1 Hot water flow path 1 connected to hot water supply pipe c in main body a
and a gas supply path 2 connected to the gas pipe d are provided adjacently and in parallel, and in the gas supply path 2, a primary side 2a communicating with the gas pipe d side and a gas burner are connected. A partition wall 21 is provided to partition the secondary side 2b, and the partition wall 21 has a first valve port 40 whose opening and closing are controlled by the first gas control valve 4 and a second valve port whose opening and closing are controlled by the second gas control valve 7. 70 are installed in parallel, and in the hot water flow path 1, an actuating body 3 that senses the flow rate of hot water and operates, and a piston 5 that operates due to temperature changes.
The operation of the actuating body 3 is connected to the first gas control valve 4 provided in the gas supply path 2 via the rod 33, and the piston 52 of the thermoelement 5 is connected to the first gas control valve 4 through the rod 33. A gas proportional control valve in a gas instantaneous water heater whose operation is linked to a second control valve 7 provided in the gas supply path 2.