JPH044379A - Hot water and cool water mixing device - Google Patents

Abstract

PURPOSE:To prevent a temperature variation owing to an error by providing variable differen tial pressure generators at the downstream sides of a hot water side and a cool water side valve bodies, and providing a valve shaft to oppose the forces of outlet pressures at the hot water side and the cool water side valve bodies, and variable operation force generating means to enforce the valve shaft. CONSTITUTION:A variable operation force generating means 13 has an inner core 14 and a coil 15, a valve shaft 17 moves up and down by increasing and decreasing the control current of a control circuit 16, and a cool water side valve body 18 and a hot water side valve body 19 are operated following the up and down movement of the valve shaft 17, to regulate the flow of the cool water and the hot water. By a partition wall body 20 provided at the center of the valve body 17, a cool water flow way 1 and a hot water flow way 12 are separated, variable differential pressure generating bodies 23 and 24 are provided at the downstream sides of the flow ways 11 and 12 respectively, and the cool water and the hot water passing through the generator bodies 23 and 24 are mixed in a mixing passage 25. The variable differential pressure generator bodies 23 and 24 are composed of variable valves 23c and 24c, and their openings are determined responding to the flow amounts. By using the variable valves, the controllable smallest water flow is reduced, and the differential pressure at the maximum flow is reduced. Consequently, the power loss of the passages can be reduced, the driving force of the variable operation force generating means 13 can be also reduced, and a temperature variation owing to a pressure regulation error is eliminat ed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a water heater that adjusts the mixing ratio of hot water and water to obtain an optimal temperature of the mixed water.

2. Description of the Related Art Conventionally, there has been a water heater of this type as shown in FIG. 1 is a hot water flow path, 2 is a water flow path, and an automatic pressure regulating valve 3 is provided in relation to each flow path, and this automatic pressure regulating valve 3 has a hot water side valve body 4, a water side valve body 5, and both valve bodies. Even if the pressure between the shaft 6 and the piston 6a connecting the hot water or water suddenly changes, the automatic pressure regulating valve 3 moves with that pressure to stabilize the mixed water temperature. This automatic pressure regulating valve 3 is used to change the mixing ratio of hot water and water by bias means 9 consisting of a coil 7 and a magnet 8.

Problems to be Solved by the Invention However, in the above configuration, since there is a fixed restriction between the hot water side valve body 4, the water side valve body 5, and the mixing section, that is, the fluid resistance is constant, there are the following drawbacks. Figure 3 shows the relationship between the flow rate on the Zunawaji hot water side or the water side and the differential pressure between the hot water side valve body 4, the water side valve body 5, and the mixing section. As shown, the differential pressure increases in proportion to the square of the flow rate, resulting in a relationship as shown in characteristic B. It is driven by the bias means 9 against the force caused by the product of this differential pressure and the cross-sectional area of the hot water side valve body 4 or the water side valve body 5.

For this reason, if the fluid resistance is increased, the bias means 9 will need a large force when the flow rate increases, and if the fluid resistance is small, the differential pressure that occurs when the flow rate is low is small, and errors caused by friction etc. cannot be ignored and the mixing ratio will be reduced. Becomes unstable.

Means for Solving the Problems - In order to achieve the object described above, the hot water mixing device of the present invention has a hot water flow path and a water flow path, a hot water side valve body that adjusts the flow rates of the hot water flow path and the water flow path, and a water flow path. A side valve body, a variable differential pressure generator having a check function provided downstream of the hot water side valve body and water side valve body, respectively, a mixing part of the hot water flow path and the water flow path, and a connection between the hot water side valve body and the water side valve body. A valve shaft that makes forces due to the outlet pressure of the side valve body oppose each other, a partition between a hot water flow path and a water flow path provided on the valve shaft, and a variable operating force generating means that applies a biasing force to the valve shaft. It is prepared.

Operation With the above configuration, the hot water side valve body and the water side valve body are operated by the variable operating force generating means to change the mixing ratio and adjust the hot water temperature.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings. In addition, in FIG. 1, the valve body 10 has a water flow path 11 and a hot water flow path 12.
There is a variable operating force generating means 13 on the water flow path 11 side, the variable operating force generating means 13 has an iron core 14 and a waterproof and insulated coil 15 around the iron core 14, and the coil 15 is connected to a control circuit. 16.

A valve shaft 17 is provided inside the valve body 10, and the upper end of the valve shaft 17 is in contact with the iron core 14. There is a water side valve body 18 on the water flow path 11 side of the valve stem 17, and a hot water side valve body 19 on the hot water flow path 12 side, and the water flow rate and the hot water flow rate are adjusted by movement of the valve stem 17. At the center of the valve stem 17 is a partition wall 20 made of a diaphragm or the like, which separates the water flow path 11 and the hot water flow path 12.
are separated. A spring 21 is attached to the lower end of the valve shaft 17 by a plug 22. The hot water and water that have passed through the water side valve body 18 and the hot water side valve body 19 are transferred to the water side variable differential pressure generating body 23.
and the hot water side variable differential pressure generator 24 and are mixed in the mixing path 25. The variable water side differential pressure generator 23 and the variable hot water side differential pressure generator 24 have springs 23b and 2 in the valve holes 23a and 24a, respectively.
The movable valve 23c is composed of movable valves 23c and 24c which are pressed against each other by a spring 23b.For example, when water flows, a pressure difference is generated on both sides of the movable valve 23c, and the movable valve 23c opens against the force of a spring 23b. The opening degree of this movable valve 23c is determined according to the flow rate of fluid passing through it.

If the spring 23b is appropriately selected, the relationship between the passing flow rate and the pressure difference can be set to the characteristic shown in FIG. 3, characteristic A. The same goes for the hot water side. These variable differential pressure generators 23 and 24
When the hot water and water passing through the tube try to flow in the opposite direction, the movable valves 23c and 24c close the valve holes 23a and 24a to prevent the backflow, as shown in FIG. 26 is a temperature detector whose signal is connected to the control circuit 16.

Next, the present invention will be explained in detail. When the control circuit 18 increases the current to the coil 15, the iron core 14 is urged downward by electromagnetic force, the valve shaft 17 moves downward, the water flow rate decreases, and the hot water flow rate increases. As a result, the temperature of the mixed water increases. Conversely, when the current is reduced, the electromagnetic force is reduced and the valve shaft 17 is moved upward by the spring 21, thereby increasing the water flow rate and decreasing the hot water flow rate. As a result, the mixed water temperature decreases. In this way, the mixed water temperature can be adjusted by changing the current flowing through the coil 15. The mixed water temperature is detected by a temperature detector 26 and calculated by a control circuit 16 to control the current to the coil 15. When the water pressure fluctuates, if the pressure-receiving areas of the water-side valve body 18, the hot-water side valve body 19, and the partition wall body 2o are made approximately equal as in the past, the change in the mixing ratio of hot water and water will be small and the hot water temperature will be stable. There is. In this way, under ideal conditions, the hot water temperature does not fluctuate due to changes in pressure or flow rate.
Pressure adjustment errors occur due to dimensional errors or resolution and reproducibility of the variable operating force generating means 13. In order to reduce fluctuations in water temperature due to pressure adjustment errors, the differential pressure generated by the differential pressure generators 23 and 24 must be at least a certain value.

If the differential pressure required for control in the characteristic A of FIG. 3 is Pl, then the minimum amount of water that can be controlled between the hot water side and the water side is Ql. On the other hand, if the maximum flow rate required by the person using the toilet is Q2, the differential pressure will be P2. When a normal orifice is used instead of a variable restrictor, as shown in characteristic B in Figure 3, if the differential pressure PL required for control is equal to that in the case of linear resistance, the minimum amount of water that can be controlled is Q.
1', and the differential pressure becomes P2' at -force and large flow rate Q2. That is, when a variable throttle is used, the minimum amount of water that can be controlled becomes smaller, and the differential pressure generated at the maximum flow rate becomes smaller.

Therefore, the pressure loss in the passage can be reduced, and the maximum required driving force of the variable operating force generating means 13 can also be reduced.

Effects of the Invention As described above, the hot water mixing device of the present invention has a hot water flow path and a water flow path, a hot water side valve body and a water side valve body that adjust the flow rates of the hot water flow path and the water flow path, and a hot water side valve body and a water side valve body that adjust the flow rates of the hot water flow path and the water flow path. variable differential pressure generators each having a check function and provided downstream of the water side valve body;
A mixing part of the hot water flow path and the water flow path, a valve shaft that opposes the forces due to the outlet pressures of the hot water side valve body and the water side valve body, and a partition between the hot water flow path and the water flow path provided on the valve shaft. and a variable operating force generating means for applying a biasing force to the valve stem, the valve stem has the following effects.

a. Pressure loss is small and the required driving force of the variable operating force generating means is small.

59 A check valve, which is normally required to be provided upstream of the water flow path and the hot water flow path, is not required, and the size and cost can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a hot water mixing device according to an embodiment of the present invention, Fig. 2 is a sectional view of a variable differential pressure generator of the same device, and Fig. 3 is a variable pressure differential between the same device and a conventional hot water mixing device. FIG. 4, which is a characteristic diagram of the generator, is a cross-sectional view of the structure of a conventional water heater. 11...Water flow path, 12...Hot water flow path, 1
3...Variable operating force generating means, 17...
Valve shaft, 18... Water side valve body, 19... Hot water side valve body, 20... Bulkhead body, 23... Water side variable pressure differential generation. Body, 24... Hot water side variable pressure difference generator, 25... Mixing path.

Claims (1)

[Claims] A hot water flow path and a water flow path, a hot water side valve body and a water side valve body that adjust the flow rates of the hot water flow path and the water side valve body, and a reverse valve body provided downstream of the hot water side valve body and the water side valve body, respectively. a variable differential pressure generator having a stopping function; a mixing section of the hot water flow path and the water flow path; a valve shaft that opposes forces due to outlet pressures of the hot water side valve body and the water side valve body; and the valve A hot water mixing device comprising: a partition between the hot water flow path and the water flow path provided on a shaft; and variable operating force generating means for applying a biasing force to the valve shaft.