JPS58221083A - Mixing valve - Google Patents

Abstract

PURPOSE:To make the operating force reducible in operating time of a control valve, by setting th control valve in motion only at the time of hot water delivery with a signal out of a flow rate detector, while making a hydraulic pressure so as not to act excessively on the control valve when it operates. CONSTITUTION:In a state that a hot water tap is closed, a control valve 6 is held in the state of inlet pressure in a feed water passage being high in pressure whereby the hydraulic pressure directly acts on the control valve 6, producing excessive frictional resistance there, but on the other hand, in the state that the hot water tap is opened, the hydraulic pressure acting on the control valve 6 is very scanty so that no hindrance will affect the operation of the control valve 6. Therefore, it means that a driver 27 is operated only in time of operating a flow rate detector 14, driving the control valve 6 at low torque in consequence.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mixing valve that mixes hot water heated by a water heater or the like with supplied water to obtain hot water at an appropriate temperature.

Mixing valves that mix hot water and water to obtain the desired hot water are already known, but most of them use the expansion of gas or liquid called thermobellets, and the response is slow and the sensitivity cannot be high, so it is difficult to supply. The drawback was that the outlet temperature fluctuated significantly due to poor followability to changes in the hot water supply temperature and water supply pressure. Although temperature detection is not performed yet, a method is known in which the desired hot water is obtained by adjusting the hot water supply and the pressure of the water supply, keeping the mixing ratio constant, and selecting the mixing ratio. There is a disadvantage that when the water temperature changes, the outlet temperature also changes accordingly.Furthermore, when operating the control valve that selects the mixing ratio, when the water is stopped, the source pressure acts and the operating force is reduced due to friction between the control valve and the main body. It also had the disadvantage of increasing As described above, the conventional mixing valve system has a large practical problem in applications such as showers that require highly accurate temperature control and operability.

The present invention aims to maintain the hot water outlet temperature at a set temperature quickly and with high precision, and to reduce the operating force when operating the temperature setting control valve to ensure smooth adjustment. .

In order to achieve the above objective, a temperature sensor is installed after the mixing section where the water supply channel and the hot water supply channel merge, a flow rate detector is installed in a part of each channel, and a control valve and its The actuator is operated only when hot water is dispensed in accordance with the signal from the flow rate sensor and the temperature sensor to prevent excessive source pressure from acting when the control valve is operated. An embodiment of the invention will be described with reference to the accompanying drawings.

In FIG. 1, 1 is a mixing valve main body, 2 is a water supply channel, and 3 is a hot water supply channel. Each channel joins in a mixing part 4, and hot water is dispensed from a faucet (not shown) through a hot water outlet channel 6. The upstream side of the water supply channel 2 is supplied with city water pipes, and the upstream side of the hot water supply channel 3 is supplied with a water heater (not shown) or the like. 6
A control valve provided in the hot water supply path 3 controls the temperature of the hot water outlet path 6 by adjusting the amount of hot water supplied. 7 is a pressure regulating valve provided in the water supply channel 2, which includes a diaphragm (pressure receiving body) 8, a control valve body 9 that follows the operation of the diaphragm 8, and a valve seat 1o integrally provided in the main body 1. A control valve is formed to adjust the pressure in the pressure chamber 11 downstream of the pressure chamber 11 . A pressure chamber 12 on the back pressure side of the pressure chamber 11 partitioned by a diaphragm is communicated with the upstream side of the control valve 6 of the hot water supply path 3 through a communication hole 13, and the pressure in the pressure chamber 11 is communicated with the pressure chamber 12, that is, the control valve 6. The pressure is controlled to be approximately equal to the pressure on the upstream side of 6. 14 is a flow rate detector, which includes a pressure chamber 1 partitioned by a diaphragm 15.
6.17, the pressure on the upstream side of the flow path is guided to the pressure chamber 16 on the high pressure side through the communication hole 18, and the pressure on the downstream side is guided to the pressure chamber 17 on the low pressure side through the communication hole 19. The diaphragm 15 detects the differential pressure when it flows into the flow path through the throttle 2o formed between the valves (-, the switch 23 is operated via the operating frame 22 against the spring 21 to detect the flow. has a hole 24 and is rotated by a driving body 27 consisting of a motor 25 and a reduction gear 26, and the flow rate of the hot water supply path 3 is adjusted by changing the passing area of the hole 24. 28 is a holding plate of the control valve 6; 29 is a temperature sensor such as a thermistor installed in the hot water outlet path 6, and is connected to the temperature setting device/control box 30 together with the driving body 27° and the flow rate detector 14 by a signal line. A check valve is provided in each of the passage 2 and hot water supply passage 3.

FIG. 2 shows a block diagram of an embodiment of the control circuit of the present invention, where A is obtained by dividing the reference voltage by a variable resistor in a temperature setting device.

B is a temperature converter that converts the temperature signal obtained from the temperature detector 29 into a voltage, and when the temperature detector 29 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 and sent to drive control circuit C as a deviation signal. The drive control circuit C amplifies the deviation signal and determines the amount of operation to be applied to the drive body 27. If the drive body 27 is a step motor, the drive control circuit C sends out a digital signal, if it is a servo motor or a solenoid, it sends out a DC signal, and if it is an AC motor, it sends out an AC signal. In the drive control circuit σ, not only proportional control but also the well-known P
ID control can be performed, and if necessary, the position of the control valve 6 can be detected with a potentiometer or the like and servo control can be performed. The drive body 27 is displaced by the drive control circuit C, and the control valve E6 is rotated via the reduction gear D26. The rotation of the control valve E changes the mixing ratio of the hot water supply amount and the water supply amount, and the newly set mixing ratio is achieved. As the amount of hot water changes, the pressure chamber 11 changes to the pressure chamber 12 through the communication hole 13.
The amount of water supplied is controlled by the pressure control valve FT so that the pressure is approximately equal to the pressure. G is a flow rate detection circuit that transmits a signal from the switch 23 of the flow rate detector 14, and is configured so that the driver 27 operates only when the flow rate is detected through control in a control box.

Next, the operation will be explained. When the hot water tap (not shown) located downstream of the hot water outlet path 5 is closed, the flow rate detector 14 is not operating, the switch 23 is open, and a signal is sent to the flow rate detection circuit G (control box 30). Since the control valve 6 and the driving body are not inserted, the control valve 6 and the driving body remain in a stationary state in the position of the previous use state. When the hot water tap is opened, hot and cold water flows into the water supply channel 2 and the hot water supply channel 3 at the temperature setting and the position of the control valve 6 that were previously used, joins in the mixing section 4, passes through the hot water supply channel 5, and is dispensed from the hot water faucet. Flow rate detector 1 detects the momentary flow when the stopper is opened.
4, the diaphragm 16 is displaced to the right in the figure against the spring 21, the contact of the switch 23 is closed through the operation 22, and a flow rate detection signal is sent to the control box 30. This contact signal is transmitted from the flow rate detection circuit G to the drive control circuit C and enters the operating state of the drive body 27 through the signal line, but at the same time as the signal from the flow rate detector, the signal from the temperature sensor 29 is also transmitted to the control box 3°. The set temperature of the temperature setting device A (inside the control box) is compared with the set temperature of the temperature setting device A (inside the control box) through the temperature converter B, and the drive body 2 is
7 will be operated. To explain in more detail, first, the temperature of the hot water coming out from the hot water supply path 5 is assumed to be a general so'c constant, although if the heat source of the hot water in the hot water supply path is a water heater, the temperature will vary depending on the temperature setting, while the water temperature in the hot water supply path Although it varies depending on the season, it is generally a constant temperature between 5 and 36°C, and if hot water and cold water at a certain temperature are mixed, the hot water temperature will inevitably depend on the flow rate ratio of hot water and water. Determined. The flow rate of hot water and water is determined by the pressure and resistance of each flow path,
The resistance value of the hot water outlet path is constant if the opening degree of the hot water tap (faucet) is constant L, and if the amount of hot water supplied is constant when the regulating valve 6 is throttled, it is determined by the upstream pressure of the regulating valve 6, and the water supply is constant. The amount is determined by the pressure in the pressure chamber 11 since the resistance value of the flow path after the pressure chamber 11 is also constant, but the pressure in the pressure chamber 11 becomes almost equal to the pressure in the pressure chamber 12 due to the action of the pressure regulating valve 7. The upstream pressure of the regulating valve 6 and the pressure in the pressure chamber 11 are adjusted by the control valve body 9 and the valve seat 10, so that the pressure in the pressure chamber 11 is always approximately equal. Therefore, in the state of the control valve 6 described above, hot water at a constant temperature can be obtained. Even if the hot water supply amount is adjusted by changing the opening degree of the hot water tap, the resistance of the hot water outlet path is a change in resistance common to both roads, so even if the equal pressure value of both roads changes, the flow rate ratio will not change. The hot water temperature does not change. In addition, the source pressure of the water supply line (water heaters usually have a pressure reducing valve, so below 0.8 to 97c, if) and the source pressure of the water supply line (usually 0.6 to 1o Ky/cnl for city water) changes. Even in this case, the pressure regulator 7 described above always maintains the same pressure, so the temperature of the hot water does not change. next,
By changing the opening degree of the control valve 6, the ratio between the amount of hot water and the amount of water supplied changes, making it possible to adjust the temperature.
If there is a difference between the temperature setting value at o and the detected value by the temperature detector 29, the motor 25 is operated through the drive control circuit C, and the speed is reduced by the reduction gear 26, and the control valve 6 is driven in the direction where the temperature difference is reduced. The resulting hot water outlet temperature is detected again by the temperature detector 9, and the above-described operation is repeated until the deviation from the set temperature becomes extremely small, so that the hot water outlet temperature can reach the set value in a very short time. As mentioned above, pressure fluctuations on both roads are instantly adjusted by the action of the pressure regulating valve 7, and there is almost no need to detect and control the temperature, and fluctuations in the hot water temperature due to delays in temperature detection are avoided. There aren't many. However, there may be cases where the heat source of the hot water supply path fluctuates greatly in instantaneous water heaters, solar water heaters, etc., but in this case as well, in the present invention, the temperature detector 29 detects the mixing temperature and operates the control valve 6. The hot water temperature remains at the set temperature.

Next, characteristic parts of the present invention will be explained.

The amount of hot water supplied by the control valve 6 is adjusted by rotating the control valve 6 through the hole 24.
The rotation is performed by changing the passage area formed by the main body 1, but since the rotation is driven by an external reduction gear 26, the surface of the control valve 6 facing the reduction gear and a holding plate to prevent the control valve 6 from protruding outside. Frictional resistance will be generated between the shaft and the shaft 28, which will impede rotation. This size corresponds to the high pressure at the inlet of the water supply channel (0.6 to 1oKy/cm) when the hot water tap (faucet) is closed.
), and the water pressure acts directly on the control valve 6, creating excessive frictional resistance.On the other hand, when the hot water tap is opened, the water pressure acting on the control valve 6 is extremely low (
0-5 to 9/crA or less), and does not interfere with the operation of the control valve 6 in any way. In the present invention, as described above, the driving body 27 is operated only when the flow rate detector 14 is operated (when detecting the flow rate), and the control valve 6 is driven with low torque. In the embodiment of the present invention, the control valve 6 controls only the hot water supply path, but this is because the hot water temperature is set at a high temperature of about 8o''C and the water supply temperature is set at 5 to 35℃, as described above.
Considering that the water temperature is ℃, if the hot water outlet temperature is set to an appropriate temperature of about 42℃, the flow rate mixing ratio of hot water and water will be approximately 1:1 to 1:5, and the total amount of hot water (hot water supply amount) must be throttled and adjusted. Therefore, by simply adjusting the amount of hot water, a high temperature of about 6°C can be obtained as the water temperature rises to 35°C. In addition, if you want to obtain high-temperature hot water (zero water amount) even when the water temperature is low, the control valve 6 can be located near the mixing section 4, so that both the hot water supply amount and the water supply amount can be adjusted with a single control valve. With this structure, the above can be achieved. Furthermore, in the embodiment of the present application, a pressure regulator is provided in the water supply channel, but if the water supply channel inlet is inserted between the pressure reducing valve on the inlet side of a water heater or other appliance and the appliance, the pressure regulator may be installed in the mixing valve body. The pressure adjustment function becomes unnecessary. The Ushida flow rate detector 14 may be configured to detect only the water supply flow rate or the hot water supply flow rate, as well as the portion including the hot water outlet path.In addition, the control box @O may be equipped with a temperature setting device. However, it may be located outside the control box.

As described above, the present invention detects the mixed temperature of hot water and controls the temperature by electrical means while maintaining the same pressure between the water supply channel and the hot water supply channel, and has a fast response and high accuracy. Not only can the temperature be controlled, but the temperature of the hot water is extremely stable against fluctuations in hot water or water pressure. Since the control valve operates only when the motor is running smoothly, there is no need to worry about the control valve malfunctioning if you try to forcefully adjust it even when the water is stopped, and you can avoid making the motor larger than necessary. , there is no need to increase the gear ratio of the reduction gear to delay response, and there is no risk of locking or damaging the motor, providing a highly reliable control valve mechanism that is reliable, quick, and inexpensive. This mixing valve has an adjustable function and is highly safe and has extremely high practical value.

[Brief explanation of the drawing]

Figure 1 shows an embodiment of the mixing valve of the present invention.
Mixing valve body, 2... Water supply channel, 3...
- hot water supply path, 4...mixing section, 5...- hot water outlet path,
6...Control valve, 7...Pressure control valve, 8...
Pressure receiving body (diaphragm), 9...control valve body, 14...-
- Flow rate detector, 27...driver, 29-...temperature detector. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2

Claims (1)

[Scope of Claims] 1. A water supply channel, a hot water supply channel, a hot water outlet channel where each of them merges in a mixing section, a control valve and its driver provided in the hot water supply channel or the mixing section, and the mixing section or the hot water supply channel. It has a temperature detector provided in the hot water outlet path and a flow rate detector that detects the flow rate of any of the flow paths, and the driving body of the control valve is activated only when fluid is flowing according to a signal from the flow rate detector. A mixing valve configured to operate in response to a signal from the temperature detector. 2. A pressure regulating valve is provided in the water supply channel, and the pressure regulating valve consists of a pressure receiving body and a control valve body that operates together with the pressure receiving body, and the pressure after passing through the front filling control valve body and the hot water supply path are connected to the pressure receiving body. 2. The mixing valve according to claim 1, wherein the mixing valve is configured such that the pressure on the upstream side of the control valve acts to perform substantially equal pressure control.