JPS5830571A - Mixing valve - Google Patents

Abstract

PURPOSE:To reduce the size of a control valve and to make the capacity of a means for driving the control valve small, by providing pressure transmitting pipes having a small diameter that are used only for transmitting pressure independently of a feed water pipe and a hot- water supply pipe, controlling water flow by the control valve, and transmitting the pressure to a pressure controller. CONSTITUTION:A first pressure chamber 5 and a second pressure chamber 6 are communicated with each other via a first connecting pipe 17 having an orifice 16, and the second pressure chamber 6 is communicated with a mixing pipe 13 via a second connecting pipe 18 and a control valve 19. The temperature of water in the mixing pipe 13 is detected by a detector 32. When the temperature thus detected by the detector 32 is lower than a set value, the control valve 19 is controlled to decrease its opening and to reduce the amount of water supplied from a feed water pipe 10. On the other hand, when the temperature of water detected by the detector 32 is higher than the set value, the valve 19 is controlled to increase its opening and to thereby increase the amount of water supplied from the feed water pipe 10. The above control is repeated until the deviation between the temperature detected by the detector 32 and the set value is reduced to an extremely small value. In the above arrangement, the diameters of feed water pipes 10, 12 and a hot-water feed pipe 14 cannot be made so small in consideration of pressure loss, but the diameters of pressure transmitting pipes 17, 18 can be made fairly small since they are required only to transmit pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mixing pulp that mixes hot water heated by a water heater and supplied water to obtain hot water at an appropriate temperature. The first objective of the present invention is to downsize the drive unit, and the second objective is to prevent hot water that is abnormally higher than the set temperature from being supplied.

BACKGROUND ART It is known to detect temperature and adjust the mixing ratio using a motor in a mixing pulp that mixes hot water to obtain desired hot water. However, in this configuration, the valve driven by the motor directly controls the hot water and water, so not only the valve becomes large but also the motor needs a large capacity motor. ``Also, if hot water that is abnormally high relative to the set temperature suddenly flows in, there is a drawback that the motor operation is delayed and hot water is supplied at a higher temperature.

The present invention eliminates these drawbacks. Hot water and water are mixed, the temperature of the mixing part is detected by a temperature detector, and a control valve activated by the signal controls a small flow. A pressure controller is operated by pressure to control a large flow and to control the mixing temperature of hot water and water to be equal to the set temperature.An example of this will be explained with reference to the attached drawings.

In FIG. 1, 1 is a pressure control valve with a diaphragm (pressure receiving body), 2 is a valve body, and 3 is a casing 4 that connects a first pressure chamber 5. A second pressure chamber 6 is formed. A pressure receiving plate 7 and a control valve body 8 are fixed to the diaphragm 2, and the control valve body 8 is connected to the valve body 3.
A control valve is formed in correspondence with the valve seat 9 attached to the valve seat 9. A water supply pipe 1o is connected to the valve body 3, and the supplied water passes through the gap between the control valve body 8 and the valve seat 9, then flows into the first pressure chamber 6, and then flows into the water supply pipe 12 having a throttle 11. (the first fluid pipe) and flows into the mixing pipe 13. 14 is the hot water pipe (
Hot water heated by a water heater (not shown) in the second fluid pipe (second fluid pipe) passes through the throttle 15 and joins the water in the aforementioned mixing pipe 13. The first pressure chamber 5 and the second pressure chamber 6 are connected by a first communication pipe 17 having a constrictor 16, and the second pressure chamber 6 is connected to a mixing pipe 1.
3 via a second communication pipe 18 and a control valve 1'9.

20 and 21 are springs, respectively. The control valve 19 has a hole 22 and is rotated by a driving body 26 consisting of a motor 23 and a reduction gear 24, so that the passage area of the hole 22 can be changed. 26 is a bypass valve connected to the outlet side of the pressure control valve 1, and an electromagnetic coil 27 and a plunger 2.
8. The lower end of the plunger 28 forms a pair of valves with the valve seat 3o, and the outlet thereof is connected to the bypass pipe 3.
1 to the mixing tube 13. Inside the mixing pipe 13 there is a temperature detector 32 such as a thermistor that converts the temperature into an electrical signal. The differential pressure generated is transmitted to the flow rate detector 35. The flow rate detector 36 forms a pressure chamber 39.40 with the diaphragm 36 and the casing 37.3B, the upstream pressure of the throttle 34 is transmitted to the pressure chamber 39, the downstream pressure of the throttle 34 is transmitted to the pressure chamber 40, and the diaphragm Axis 4 cooperating with 36
1 opens and closes the switch contact 42. 43 is a pressure receiving plate, 44
is a spring.

FIG. 2 is a block diagram showing an embodiment of the control circuit of the present invention, where A is a temperature setting device obtained by dividing a reference voltage by a variable resistor. B is temperature detector 3
This is a temperature converter that converts the temperature signal obtained from 2 into a voltage, and if the temperature detector 32 is a thermistor, it is composed of a bridge circuit and its amplification circuit. The voltages of temperature setter A and temperature converter B are compared to form a deviation signal, which is sent to drive control circuit C. The drive control circuit C amplifies the deviation signal and determines the amount of operation to be applied to the drive body 22. If the drive body 25 is a step motor, the drive control circuit C sends out a digital signal, if it is a servo motor or an lenoid, it sends out a DC signal, and if it is an AC motor, it sends out an AC signal. Drive control circuit C can perform not only proportional control but also known P and ID control, and drive control circuit C can perform servo control by detecting the position of control valve 19 with a potentiometer or the like. . The drive body 26 is displaced by the drive control circuit C and rotates the control valve E (FIG. 19) via the reduction gear D (FIG. 1 24), and the rotation of the control valve E causes the pressure control valve F ( Figure 1 1)
change the pressure acting on the G is a flow rate detector that transmits a signal from the switch contact 42 of the flow rate detector 35, and H is a bypass valve control circuit that opens and closes the bypass valve 26 in accordance with the above-mentioned deviation signal.

Next, the operation will be explained. When the hot water tap (not shown) downstream of the hot water outlet pipe 33 is closed, the switch contact 42 of the flow rate detector 35 is closed, and the flow rate detection circuit G causes the drive control circuit C to fully close the control valve 19. I'm in charge of Shima. When the hot water faucet is opened, the control valve 19 is initially fully closed, so the pressure in the second pressure chamber 6 is high and the control valve element 8 is almost fully open. A larger amount of water flows, and low-temperature hot water flows into the mixing pipe 13. When a differential pressure is generated in the throttle 34, the shaft 41 of the flow rate detector 36 moves upward, the switch contact 42 opens, and this contact signal is transmitted through the flow rate detection circuit G to the drive control circuit C, and the control valve 19 Release the fully closed hold. Thereafter, the temperature detector 32 detects the temperature of the mixing pipe 13, and if it is lower than the set temperature, controls the control valve 19 in the opening direction. When the control valve 19 opens, the fluid resistance decreases, and the throttle 16 and the control valve 1
The pressure in the pressure chamber 6 determined by the fluid resistance ratio of 9 decreases. Therefore, the control valve body 8 moves in the closing direction, the amount of water in the water supply pipe 1o decreases, and the temperature of the mixing pipe 13 increases.゛This increased temperature is compared with the set temperature again, and if it is lower than the set temperature, the control valve 19 is controlled in the open direction to reduce the water amount in the water supply pipe 10, and if it is higher than the set temperature, the control valve 19 is controlled in the close direction. The amount of water in the water supply pipe 10 is increased, and the above-described operation is repeated until the deviation between the temperature of the temperature detector 32 and the set temperature becomes extremely small. The water supply pipes 10 and 12 and the hot water supply pipe 14 cannot be made too thin because pressure loss must be considered, but the first communication pipe 17 and the second
Since the communication pipe 18 only transmits pressure, it is possible to use relatively small diameter piping, and similarly the control valve 19
It also consists of small valves. Therefore, the control valve 19 can be operated with low torque, and the driving body 25 can be configured with a small-sized, low-capacity device.

゛The temperature of the supplied hot water may fluctuate slowly but greatly over time in a solar water heater or the like, but in this case as well, in the present invention, the temperature detector 32 detects the mixing temperature. Since the control valve 19 is operated, the water temperature is maintained at the set temperature. In the shower, the supply of hot water at an abnormally high temperature is not only uncomfortable, but even dangerous. In the present invention, when the hot water temperature is detected by the temperature sensor 32 as being abnormally high relative to the set temperature, the electromagnetic coil 27 of the bypass valve 26 is energized by the valve control circuit H, and the plunger 26 is moved upward. This prevents the water from being supplied at an abnormally high temperature by moving the water to the mixing pipe 13 through the bypass pipe 31.

When the hot water tap is closed, no differential pressure is generated across the throttling valve 34, the switch contact 42 is closed, and the driving body 26 is operated to fully open the regulating valve 19. This operation not only sets the initial position of the regulating valve 19 in a control system that does not detect the position of the regulating valve 19, but also supplies more water than the initial hot water when the hot water tap is opened again. In other words, since hot water is always supplied at a low temperature in the mixing pipe 13, even if there is a dispute over the set temperature or the hot water in the hot water supply pipe 14 is abnormally high, it is possible to prevent hot water from being supplied at a high temperature unexpectedly and causing burns. It is what it is. The fully closed position can be detected by detecting the rotational position of the control valve 190 using a switch.

In the embodiment, the pressure control valve 1 was arranged on the water supply pipe 10 side and the regulation valve 19 on the hot water supply pipe 14 side, but the pressure control valve 1 was arranged on the hot water supply pipe 14 side and the regulation valve 16 on the water supply pipe 10 side. You can also get a similar effect with crab.

In this case, the bypass valve 26 is installed on the water supply pipe 1o side.
, get kicked. Further, the flow rate detector 36 may be configured to detect the water supply flow rate or the hot water supply flow rate instead of the mixed total flow rate, and the same effect can be obtained by using a manual switch in place of the flow rate detector 35. can.

As mentioned above, the present invention provides a thin pressure communication pipe that transmits pressure separate from the water supply pipe/hot water supply pipe, and controls the flow with a control valve and transmits it to the pressure controller. The control valve can be constructed in a compact size, and the driving body of the control valve can be made of low-capacity parts, resulting in a reduction in cost. Furthermore, the function of the binos valve and flow rate detector prevents the supply of hot water at an abnormally high temperature compared to the set temperature, making it highly safe.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a mixing valve according to an embodiment of the present invention, and Fig. 2 is a block diagram of the same control circuit. 1...Pressure control valve, 2...・Diaphragm (pressure receiving body), s, 6... First pressure chamber, second pressure chamber, 8... Control valve body, 12... Water supply pipe (first fluid pipe), 11-13...mixing pipe, 14...hot water supply pipe (second fluid pipe), 1, 7, 18...first communication pipe,
Second communication pipe, 19... (control valve), 25...
...Driver, 26...Bypass valve, 31...
...Bypass pipe, 32 ...Temperature detector, 3
6...Flow rate detector. Name of agent: Patent attorney Toshio Nakao and 1 other person11
11 figure 1ri 12 figure

Claims (4)

[Claims] (1) a pressure control valve consisting of a control valve body cooperating with a pressure receiving body; a first fluid pipe connected to the pressure control valve; a second fluid pipe; the first fluid pipe and the second fluid; a mixing tube for mixing fluids in the tube; a temperature sensor provided in the mixing tube;
A first pressure chamber and a second pressure chamber divided by the pressure receiving body, a first communication passage connecting the first pressure chamber and the second pressure chamber, and connecting the second pressure chamber and the mixing pipe. 1. A mixing pulp comprising: a second communication path for communicating with the user; and a control valve provided in the first communication path or the second communication path, the control valve being actuated by a signal from the temperature sensor. (2) The mixing pulp according to claim 1, wherein the first fluid pipe is a water supply pipe to which city water is supplied, and the second fluid pipe is a hot water supply pipe to which heated hot water is supplied. . 27, ・ (3) It has a bypass pipe separate from the first water supply pipe that connects the pressure control valve and the mixing pipe, and a bypass valve provided in the bypass pipe, so that the difference between the temperature of the mixing pipe and the set temperature is The mixing pulp according to claim 2, wherein the bypass valve is opened when a set value is exceeded. (4) Claim 2, characterized in that it has a flow rate detector that detects the flow rate of any one of the water supply pipe, hot water supply pipe, and mixing pipe, and returns the control valve to the reference position when the fluid stops.
Mixing pulp of section.