JP3295988B2 - Hot water mixing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot and cold water mixing apparatus.
More specifically, the present invention relates to a hot and cold water mixing apparatus that urges a movable valve body to mix hot and cold water using a spring made of a material whose spring constant changes with temperature.

[0002]

2. Description of the Related Art Conventionally, as this kind of hot water mixing apparatus,
An automatic temperature-adjustable hot-water mixer tap that controls the temperature of the hot-water mixture by urging the movable valve body, which controls the mixing ratio of hot water and water, with a shape memory alloy whose shape changes depending on the temperature is proposed. (June 61-4406)
2). This is because, when the shape memory alloy is set to a certain shape at a specific temperature, the initial setting temperature is given even if the shape is physically changed at other temperatures, so that the shape memory alloy is set again at the time of setting. It has the feature of restoring its shape,
It utilizes the fact that it has a smaller heat capacity and operates more sensitively to temperature changes than conventional thermosensitive elements, for example, wax thermos.

In this mixer tap, one of the movable valve bodies is urged by a coil-shaped shape memory alloy, and the other is urged by a coil spring. It is arranged so that it may contact directly.
Further, the coil-shaped shape memory alloy is said to have a constant coil length at a constant temperature, and this coil-shaped shape memory alloy is
According to the change in the temperature of the hot and cold water mixture, the operation is performed as follows.

When the temperature of the hot and cold water mixture is in a steady state at a set temperature, the movable valve body is stopped at a position where the coil shape memory alloy and the coil spring are balanced. When the temperature of the water-water mixture in the steady state changes due to disturbance or the like and becomes a constant temperature, the coil-shaped shape memory alloy generates a shape restoring force in an attempt to restore the coil length set at the temperature. . This shape restoring force breaks the balance with the coil spring in the steady state, and drives the movable valve body to the coil spring side or the coil-shaped shape memory alloy side. Here, if the coil length is continuously set near the set temperature with respect to the coil-shaped shape memory alloy, the coil-shaped shape memory alloy has a lower temperature when the temperature of the hot water mixture changes near the set temperature. The coil length is changed according to the change, and a continuous shape restoring force is generated. Accordingly, the movable valve body is displaced in accordance with the temperature change of the hot and cold water mixture and changes the ratio of hot and cold water, so that the temperature of the hot and cold water mixture can be maintained at the set temperature.

[0005]

However, in the conventional hot and cold water mixing apparatus, a coil-shaped shape memory alloy of a type in which the length of the coil changes depending on the temperature is used. In the case of a shape memory alloy of the same length, there is a problem that it cannot be used as it is. Shape memory alloys have a difference in spring constant between temperature rise and fall (temperature hysteresis), a difference in spring constant due to aging, and a characteristic error between lots. There was a problem that it was not possible.

[0006] In addition, the change of the set temperature of the hot water mixture
Since this is performed by manually applying a preload to the spring that biases the valve element, there has been a problem that a desired tapping temperature cannot be obtained by an external setting using a remote control device or the like. Further, the temperature control using only the shape memory alloy has a problem that when the shape restoring force of the shape memory alloy and the elasticity of the coil spring are balanced at a temperature deviating from the desired tapping temperature, the desired tapping temperature cannot be achieved. there were.

The hot and cold water mixing apparatus of the present invention has been made to solve the above-mentioned problems and has an object to stably maintain the temperature of the hot and cold water mixture at a target temperature, and has the following configuration.

[0008]

As shown in FIG. 1, a hot water mixing apparatus according to the present invention includes a hot water mixing valve MV having a movable valve body for adjusting a hot water mixing ratio, and a hot water mixing valve MV having a predetermined temperature range. A first spring SP1 for urging the movable valve body in a direction to decrease the proportion of hot water with a rise in the temperature of the hot water mixture flowing out of the mixing valve MV; A second spring SP2 for urging the valve body in a direction opposite to the direction, the first and second springs SP2;
Preload adjusting means M1 capable of adjusting at least one of the spring preloads, temperature detecting means M2 for detecting the temperature of the hot and cold water mixture, and controlling the preload adjusting means M1 to adjust the preload to the hot and cold water mixture. Initial preload setting means M3 for setting an initial value corresponding to the target temperature, and if there is a deviation between the temperature detected by the temperature detecting means M2 and the target temperature after the setting, the deviation is set to An electronic control means M4 for controlling the preload adjusting means M1 is provided on the canceling side, and the preload adjusting means M1 adjusts the temperature of the first spring to hot water.
The gist of the invention is that the heating means is controlled separately from the temperature .

Here, in the hot and cold water mixing apparatus, the preload adjusting means M1 may be a means for changing the effective length of the first or second spring. In addition,
The movable valve element may be a configuration for biasing by electromagnetic induction in the biasing direction of the first or second spring.

[0010]

[Action] above hot and cold water mixing device constructed as described, when the hot water is started, the initial preload setting means M3 is preload adjustment
By controlling the joint means M1, the position of the movable valve body is set to an initial value corresponding to the target temperature of the hot and cold water mixture. Further, the first spring SP1 changes a spring constant according to the temperature of the hot and cold water mixture, biases a movable valve body that adjusts the hot and cold water mixing ratio, and controls the temperature of the hot and cold water mixture to the target temperature. First spring S
If only the temperature control by P1 causes a deviation between the temperature of the hot and cold water mixture detected by the temperature detecting means M2 and the target temperature, the electronic control means M4 controls the preload adjusting means M1 to cancel the deviation. Then, the temperature of the hot and cold water mixture is set as the target temperature. In controlling such preload adjusting means M1,
And the temperature of the first spring is controlled separately from the temperature of the hot water.
You.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to further clarify the structure and operation of the present invention described above, preferred embodiments of the present invention will be described below. FIG. 2 is a schematic view of a hot water mixing apparatus according to one embodiment of the present invention, and FIG. 3 is a perspective view of the hot water mixing apparatus.

A hot water mixing device 10 includes a water supply leg 11 for supplying water from a water pipe, a hot water supply leg 12 for supplying hot water from a water heater (not shown), and a valve unit 15 for mixing hot water. And a control unit 18 for electrically controlling the mixing ratio of hot and cold water. Valve unit 15
Functionally, a water / water mixing valve 60 that mixes water supplied from the water supply leg fitting 11 and hot water supplied from the hot water supply leg fitting 12, and a movable valve body 70 incorporated in the hot / water mixing valve 60. A preload adjusting mechanism 100 for adjusting the position, a temperature sensor 110 for detecting a mixed hot and cold water temperature TC, and a shower 1
And a switching / water stop valve 120 for selecting and stopping the mixed hot water from the water supply 30 or the caran 140. Specific configurations of these will be described later. Control unit 1
Reference numeral 8 denotes a liquid crystal display (LCD) 1 for displaying a target temperature TP.
60, a panel operation unit 170 for performing operations such as setting of a target temperature TP and selection of water discharge, and a preload adjusting mechanism 100 which inputs a temperature signal detected by the temperature sensor 110 and a signal from the panel operation unit 170 to Switching / water stop valve 1
20 and an electronic control unit 150 that outputs an output signal to the LCD 160. Further, the hot and cold water mixing device 10 includes a battery 18.
0 to supply necessary power to each unit.

Next, the structure of the water supply leg 11 will be described with reference to FIG. 4 which is an enlarged sectional view of the water supply leg 11. The water supply leg fitting 11 has a housing 20 in which an inlet 21 connected to a water pipe and an outlet 29 connected to a hot water mixing valve 60 are formed, as shown in FIG. The water valve 22 and the pressure control valve 30 are incorporated.

The water stop valve 22 includes a cap 27 which is fastened to the housing 20 in a liquid-tight manner;
It has a valve element 23 guided to zero and a strainer 28. The valve element 23 has a guide portion 24 and an end 26 with the housing 20, and the guide portion 24 is provided with an opening 25 serving as a water passage when water flows. The guide portion 24 is meshed with the housing 20 with a screw, and has a structure in which the valve body 23 is displaced in the rotation axis direction by rotating the valve body 23. Therefore, by rotating the valve body 23, the end 2
By attaching and detaching the housing 6 and the housing 20, water is stopped or water is passed. During the passage of water, the water flowing from the gap between the end portion 26 and the housing 20 passes through the opening 25, and flows into the pressure control valve 30 after dust is removed by the strainer 28.

The pressure control valve 30 is a valve for controlling the water-side pressure supplied to the valve unit 15. A valve seat 31 is formed in the housing 20 in an annular shape, and the flow of water cooperates with the valve seat 31. , A guide member 35 for slidably storing the valve member 32, a valve shaft 40 fixed to the valve member 32, a metal bellows 45 to which the end of the valve shaft 40 is attached, and the like. The valve member 32 includes a nut 34
The main body 32A to which the valve shaft 40 is fixed by the
And a cylindrical skirt 33 extending in the opposite direction,
The skirt 33 is housed with a slight clearance in a bore 36 of a guide member 35 fastened to the housing 20 in a liquid-tight manner. Therefore, the valve member 32 and the skirt 3
A secondary water supply pressure P2 downstream of the valve seat 31 is introduced into a secondary pressure chamber 37 formed by the guide member 3 and the guide member 35.

The valve shaft 40 is provided with a spring receiver 41 at an end opposite to the valve member 32.
A cap 42 is fastened to the spring receiver 41 in a liquid-tight manner. A metal bellows 45 is disposed between the spring receiver 41 and the cap 42 in a liquid-tight manner, and forms a back pressure chamber 46. The metal bellows 45 is a spring having a constant spring constant, and the effective pressure receiving area is set to be equal to the effective area of the valve seat 31. The hot water supply pressure P3 from the water heater is introduced into the back pressure chamber 46 by a pressure introducing pipe 58 connected to the hot water supply leg fitting 12.

The pressure control valve 30 constructed as above operates as follows. The valve member 32 receives a force acting in the valve opening direction by the feed water primary pressure P1 and a force acting in the valve closing direction by the feed water secondary pressure P2 of the secondary pressure chamber 37. The spring receiver 41 has a force acting in the valve closing direction by the primary water supply pressure P1, a spring force acting in the valve opening direction by the metal bellows 45, and a force acting in the valve opening direction by the hot water supply pressure P3 in the back pressure chamber 46. And receive. Since the valve member 32 and the spring receiver 41 are connected by the valve shaft 40, the force acting on the valve member 32 in the valve opening direction due to the primary water supply pressure P1 and the spring receiver 41 acting in the valve closing direction due to the primary water supply pressure P1. The force is substantially balanced, and the spring force acting in the valve opening direction by the metal bellows 45 and the hot water supply pressure in the back pressure chamber 46 are different from the force acting in the valve closing direction due to the water supply secondary pressure P2 in the secondary pressure chamber 37. P
3 and the resultant force acting in the valve opening direction is balanced. Accordingly, the water supply secondary pressure P2 becomes higher than the hot water supply pressure P3 by the spring force of the metal bellows 45, and even if the water supply primary pressure P1 from the water pipe and the hot water supply pressure P3 from the water heater change,
The differential pressure between the water supply secondary pressure P2 and the hot water supply pressure P3 is constant.

Although the structure of the hot water supply leg fitting 12 is not particularly shown, a water stop valve 52 similar to the water stop valve 22 incorporated in the water supply leg fitting 11 is incorporated.

Next, the structure of the valve unit 15 will be described with reference to FIG. 5, which is an enlarged sectional view of the valve unit 15. The valve unit 15 is, as shown in FIG.
1, a hot water mixing valve 60, a preload adjusting mechanism 1
00, a temperature sensor 110 and a switching / water stop valve 120 are incorporated. A water inlet 85 and a hot water inlet 95 are formed in the housing 61. The water inlet 85 is connected to the outlet 29 of the water supply leg fitting 11, and the hot water inlet 95 is connected to the outlet 59 of the hot water supply leg fitting 12. Is done.

The hot water mixing valve 60 includes annular passages 86 and 96 communicating with the water inlet 85 and the hot water inlet 95, a valve chamber 63 accommodating the movable valve body 70 slidably in the axial direction, and a hot water mixing chamber 64. Have. The valve chamber 63 is defined by a water-side valve seat 87 and a water-side valve seat 97 that are perpendicular to the axis of the hot and cold water mixing valve 60, and an axial bore 62. The movable valve body 70 is
It has a cylindrical portion 71 and a radial web 72. A minute clearance is provided between the outer diameter of the cylindrical portion 71 and the inner diameter of the bore 62. A plurality of openings 73 are provided in the web 72 of the movable valve body 70. Hot water flowing into the valve chamber 63 from the hot water inlet 95 flows into the hot and cold water mixing chamber 64 through the openings 73 and is mixed with water. The mixing ratio of water and hot water changes as the movable valve body 70 is displaced in the axial direction.
If the movable valve element 70 is displaced to the position where it engages with the water-side valve seat 87 to shut off water, only hot water flows out, and the movable valve element 70 displaces to the position where it engages with the hot-water valve seat 97. If you shut off the hot water, only water will flow out.

The movable valve body 70 is structured so as to be positioned by the balance between the forces of a temperature-sensitive coil spring 80 disposed in the hot and cold water mixing chamber 64 and a second coil spring 90 disposed in the valve chamber 63. . For this reason, one end of the temperature-sensitive coil spring 80 is supported by a spring receiver 75 fixed to the housing 61 by a retaining ring 74, and the other end is supported by a spring receiver 76 fixed to the movable valve body 70.
One end of the second coil spring 90 is connected to the movable valve body 70.
The other end is supported by the movable spring support 102 of the preload adjusting mechanism 100. For ease of assembly, a spring catch 76 extends through the web 72,
It is structured to be screwed with the spring receiver 77.

The temperature-sensitive coil spring 80 is made of a metal whose spring constant changes according to the temperature.
The coil spring 90 is formed of a normal spring material having a constant spring constant with respect to temperature. As a metal material whose spring constant changes according to temperature, an alloy belonging to the category of a shape memory alloy (SMA) made of a nickel-titanium alloy is known. In this type of SMA, the elastic coefficient changes according to the temperature, and as a result, the spring constant of the temperature-sensitive coil spring 80 made of SMA changes according to the temperature. Temperature-responsive temperature-sensitive coil springs 80 made of SMA and having desired temperature characteristics can be obtained from various suppliers. For example, there is "KTS-SM Alloy" of Kanto Special Steel Co., Ltd.

In order to save the energy of the battery 180 consumed by the preload adjusting mechanism 100, the spring constant and the preload of the temperature-sensitive coil spring 80 are set so that the spring force (generated load) becomes sufficiently small. Must be set. On the other hand, the temperature-sensitive coil spring 80 operates under a low-temperature condition in which only water is to be discharged (at this time, the preload applied to the second coil spring 90 can be made zero, and the movable valve body 70 In this case, the spring force is required to press the movable valve body 70 against the hot water side valve seat 97 with a sufficient force to block the inflow of hot water. For this reason, the spring constant and the preload of the temperature-sensitive coil spring 80 are such that the spring force generated at a low temperature (for example, when the water supply temperature is 5 ° C.) is 500 g or less.
Preferably, it is set to be 300 g or less.

The preload adjusting mechanism 100 is configured to change the preload of the second coil spring 90 by rotating the preload adjusting motor 105 in any direction. Therefore, a movable spring receiver 102 is spline-fitted to the end member 101 which is fastened to the housing 61 in a liquid-tight manner so as to be axially displaceable and non-rotatable. Preload adjustment motor 105
The worm 104 formed on the output shaft 103 is meshed. Also, the output shaft 103 of the preload adjusting motor 105
Is sealed by an O-ring 106.

The preload adjusting mechanism 100 thus configured
Rotates the preload adjusting motor 105 in a predetermined direction,
By displacing the movable spring receiver 102 to the right in FIG. 5, the preload of the second coil spring 90 is increased, and the preload adjusting motor 105 is rotated in the opposite direction to displace the movable spring receiver 102 to the left. Thus, the preload of the second coil spring 90 is reduced.

The temperature sensor 110 is arranged such that the temperature sensing part thereof is in direct contact with the mixed hot and cold water flowing out of the hot and cold water mixing valve 60.
It is arranged downstream of a spring receiver 75 which is an outlet of the hot and cold water mixing valve 60, and is fastened to the housing 61 in a liquid-tight manner.

The switching / water shutoff valve 120 is a temperature sensor 110
, A fixed disk 121 fixed to the housing 61, a rotating disk 125 rotating while being rubbed against the fixed disk 121, and a switching / water stopping motor for rotating the rotating disk 125. 127. The fixed disk 121 has two water discharge ports 122 and 123 as shown in FIG.
One water discharge port 122 is connected to the shower 130 via a connection fitting 131 and a shower hose 132 (see FIG. 3), and the other water discharge port 123 is connected to a callan 140 via a connection metal 141 and a swivel joint (not shown). I have. The rotating disk 125 has only one water discharge port 126 that communicates with the hot and cold water mixing chamber 64 of the hot and cold water mixing valve 60 as shown in FIG. When the switching / water stopping motor 127 is rotated to align the water discharge port 126 of the rotating disk 125 with the water discharge port 122 of the fixed disk 121, the mixed hot water is supplied to the shower 130, and the water discharge port 126 is changed to the water discharge port 123 of the fixed disk 121. And the mixed hot and cold water is supplied to the curan 140, and the water discharge port 126 is connected to any of the water discharge ports 122 and 1 of the fixed disk 121.
Water is stopped when offset from 23.

The electronic control unit 150 constituting the control unit 18 is constituted as a logical operation circuit mainly composed of a microcomputer as shown in FIG. More specifically, CPU 150a, CPU 1 that executes various arithmetic processes for controlling hot water supply according to a preset control program
A ROM 150b in which a control program, control data, and the like necessary for executing various arithmetic processing in 50a are stored in advance;
Similarly, a RAM 150 for temporarily reading and writing various data necessary for executing various arithmetic processes in the CPU 150a.
c, a backup RAM 150 d capable of holding data even when the power is off, a temperature sensor input circuit 150 e for inputting a signal from the temperature sensor 110, and a panel operation unit 17
Switch input circuit 15 for inputting a switch signal from 0
0f, a motor drive circuit 15 that outputs a drive signal to the preload adjusting motor 105 in accordance with the calculation result of the CPU 150a.
0g, switching / water stopping motor 12 according to the input of a water discharging selection switch or a water discharging stop switch of panel operation section 170.
7. A motor drive circuit 150h for outputting a drive signal to the LCD 7 and an LCD drive circuit 15 for outputting a display signal to the LCD 160
0i and the like. Further, the electronic control device 150 includes a constant voltage circuit 150j connected to the battery 180.

As shown in FIG. 3, a panel operation section 170 constituting the control unit 18 includes a switch 171 for decrementing the target temperature TP displayed on the LCD 160,
A switch 172 for incrementing the target temperature TP;
It is composed of a shower selection switch 175 for selecting water discharge from the shower 130, a callan selection switch 176 for selecting water discharge from the callan 140, and a water stop switch 177 for selecting water stop.

Next, the hot and cold water mixing apparatus 1 thus configured
0 will be described with reference to flowcharts shown in FIGS.

FIG. 9 shows a processing routine at the time of tapping, which is executed when tapping is started. This routine is executed when the shower selection switch 175 or the callan selection switch 176 of the panel operation unit 170 is pressed and a switch signal is input via the switch input circuit 150f.

First, RO is set as the target temperature TP of the mixed hot water.
The default value TD stored in M150b (for example, 4
(0 ° C.) and the current preload adjustment amount FD stored in the backup RAM 150d and the current preload adjustment amount FD are executed (steps S100 and S110), and the default value TD is displayed on the LCD 160 (step S1).
20). Next, the mixed hot water temperature TC and the preload adjustment amount FS
A preload adjustment amount FS corresponding to the default value TD is obtained from a map (not shown) representing the relationship with (step S130). The difference between the obtained preload adjustment amount FS and the current preload adjustment amount FD is set to the actual preload adjustment amount ΔF (step S140), and the current preload adjustment amount FD is set to the actual preload adjustment amount ΔF.
(Step S150). That is, by driving the preload adjustment motor 105 by an amount corresponding to the actual preload adjustment amount ΔF, the worm 104 rotates,
The movable spring receiver 102 changes its axial position, and the amount of preload of the second coil spring 90 is adjusted.

Here, the default value TD may be set any number of times. However, in order to prevent hot water or cold water from flowing out of a shower or the like at the start of hot water supply, the mixed water temperature TC is normally used. It is desirable. Further, a configuration without the default value TD may be adopted, but the movable valve body 70 is controlled so that the mixed hot / cold water temperature TC becomes normally used when the tapping is finished.
Is also desirable. In this case, step S1
Steps 00 to S150 are unnecessary.

Next, it is determined which of the shower selection switch 175 and the callan selection switch 176 has been pressed (step S160). In accordance with the determination of the switch, the switching / water stop motor 127 is driven to align the water discharge port 126 of the rotating disk 125 with the water discharge port on the side of the pressed switch (steps S170, S18).
0). Water discharge port 122 or 123 and rotating disk 1
When the 25 water discharge ports 126 are aligned, hot water is started from the shower 130 or the curan 140, and this routine ends.

Next, the processing when the setting of the target temperature is changed will be described with reference to a target temperature changing processing routine shown in FIG. This routine is based on the target temperature TP
Is executed when the switch 171 or 172 for setting is pressed.

First, a process of reading the set target temperature TP and the current preload adjustment amount FD is executed (step S20).
0, 210), the preload adjustment amount FS corresponding to the target temperature TP is obtained from the above-mentioned map representing the relationship between the mixed hot and cold water temperature TC and the preload adjustment amount FS (step S220).
Next, the obtained preload adjustment amount FS and current preload adjustment amount FD
Is set to the actual preload adjustment amount ΔF (step S2).
30), the current preload adjustment amount FD is increased by the actual preload adjustment amount ΔF (step S240), and this routine ends.

9 and 10, the switches 171 and 171 for setting the target temperature TP are set.
By 172, the mixed hot and cold water is discharged at the set temperature. The adjustment of the tapping temperature at this time is performed by a temperature-sensitive coil spring 80 using SMA. Next, this operation will be described.

When the temperature of the mixed hot and cold water TC reaches the target temperature TP and the conditions such as the hot water supply temperature from the water heater, the tap water temperature and the flow rate are in a steady state, the movable valve body 70 moves the mixed hot and cold water in the hot and cold water mixing chamber 64. Therefore, the position is determined by the balance between the spring force generated in the temperature-sensitive coil spring 80 and the spring force (preload) of the second coil spring 90, and the second coil spring 90 is stationary. From this state, when conditions such as the hot water supply temperature from the hot water supply device, the tap water temperature or the flow rate fluctuate due to disturbance, the temperature TC of the mixed hot water in the hot water mixing chamber 64 deviates from the target temperature TP in accordance with the fluctuation, and the temperature deviation ΔT Occurs. The temperature-sensitive coil spring 80 changes the spring constant according to the temperature change, and as a result, the spring force of the temperature-sensitive coil spring 80 changes. The obtained mixed hot / cold water temperature TC is equal to the target temperature TP.
If it is higher, the spring force of the temperature-sensitive coil spring 80 increases, and the movable valve body 70 is displaced to the left in FIG. 5 while increasing the preload of the second coil spring 90, so that the proportion of hot water decreases. As a result, the mixed hot water temperature TC decreases. Conversely, when the mixed hot / cold water temperature TC is lower than the target temperature TP, the spring force of the temperature-sensitive coil spring 80 decreases, and the second
By the action of the coil spring 90, the movable valve body 70
Allows displacement to the right, reducing the proportion of water,
The mixed hot water temperature TC increases. By the action of the temperature-sensitive coil spring 80, the mixed hot / cold water temperature TC becomes the target temperature T
It is held at P.

After the tapping is started by the tapping start processing routine or after the target temperature TP is changed by the target temperature change processing routine, the mixed tap water temperature TC is controlled by the feedback control processing routine shown in FIG. You. This routine is executed every predetermined time, for example, every 100 ms.

In this routine, first, it is determined whether or not 5 seconds have elapsed since the start of tapping, and 3 seconds after the target temperature TP was changed.
It is determined whether or not seconds have elapsed (steps S300, S3
10) If 5 seconds have not elapsed since the start of tapping, or if 3 seconds have not elapsed since the change of the target temperature TP, this routine ends. Here, the reason why the feedback control is executed only after elapse of 5 seconds from the start of hot water supply is as follows.
This is because the mixed water temperature TC immediately after tapping is not stable. In other words, due to the lapse of time since the last stop of hot water,
Since the hot water in the pipe has not reached the predetermined temperature, the mixed hot water immediately after the tapping is considerably lower than the target temperature TP,
This is because the temperature rises sharply when the hot water from the water heater starts to flow. Therefore, the time from the start of tapping, which is 5 seconds in this embodiment, to the start of feedback control is a value determined by the distance between the hot water supply device, which is a hot water supply source, and the hot water mixing device 10, and the like. It may be determined according to the piping conditions of the above. The reason why the feedback control is executed only after the lapse of three seconds from the change of the target temperature TP is that the mixed hot and cold water temperature TC immediately after the change of the target temperature TP is in a transitional period and a certain time is required for stabilization. is there. Therefore, in the present embodiment, the time is set to 3 seconds. However, since the value of 3 seconds is determined by the capacity of the hot water mixing apparatus 10, the position of the temperature sensor 110, and the like, it may be determined by the characteristics of the hot water mixing apparatus 10.

Next, a process of reading the target temperature TP and the mixed hot / cold water temperature TC detected by the temperature sensor 110 is executed (step S320), and the difference between the target temperature TP and the mixed hot / cold water temperature TC is set to the temperature deviation ΔT (step S320). Step S33
0). The absolute value of the set temperature deviation ΔT is set to a threshold Tre.
If the absolute value of the temperature deviation ΔT is smaller than the threshold value Tref, the routine ends. Here, the threshold value Tref is a maximum value in a temperature range allowed from the target temperature TP. When the mixed hot and cold water temperature TC is controlled within 1 ° C. from the target temperature TP, the threshold value Tref has a value of 1, and the target temperature TP When the temperature is controlled within 0.5 ° C., the threshold value Tref has a value of 0.5. This threshold Tre
f is determined by the minimum value at which the preload adjusting motor 105 can be driven and controlled, the characteristics of the temperature-sensitive coil spring 80, and the like.

When the absolute value of the temperature deviation ΔT is larger than the threshold value Tref, the actual preload adjustment amount ΔF is calculated by multiplying the temperature deviation ΔT by the proportional constant K (step S350), and the current preload adjustment amount FD is calculated. The load adjustment amount ΔF is increased (step S360), and this routine ends. Here, in the present embodiment, the relationship between the temperature deviation ΔT and the actual preload adjustment amount ΔF is calculated by the proportionality constant K. However, a configuration in which the value of the proportionality constant K differs depending on the temperature deviation ΔT may be used. The actual actual preload adjustment amount ΔF is set to a constant value irrespective of the temperature, and the temperature deviation ΔT within a certain range is set to the first actual preload adjustment amount ΔF1, and the temperature deviation ΔT is set to the second actual preload adjustment amount ΔT. A configuration or the like with the load adjustment amount ΔF2 is also suitable.

The hot and cold water mixing apparatus 10 of the embodiment described above
According to the above, the temperature-sensitive coil spring 80 made of SMA whose spring constant changes with temperature is used, so that even if the mixed hot and cold water temperature TC changes due to disturbance or the like, the spring constant of the temperature-sensitive coil spring 80 becomes lower than the temperature. The movable valve body 70 is displaced toward the side where the temperature change is canceled by changing the temperature in response to the change, and the mixed hot and cold water temperature TC can be set to the target temperature TP. Further, since the temperature-sensitive coil spring 80 is made of SMA having a small heat capacity and is configured to be in direct contact with the mixed hot and cold water, it can quickly respond to a change in the mixed hot and cold water temperature TC. Therefore, the mixed hot and cold water temperature TC can be maintained at the target temperature TP.

At the start of tapping or when the target temperature TP is changed, the preload adjustment amount FS corresponding to the default value TD or the target temperature TP is determined to determine the position of the movable valve body 70. The mixed hot / cold water temperature TC can be set to the default value TD or the target temperature TP early after the change of the TP.

When a temperature deviation ΔT occurs between the mixed hot and cold water temperature TC and the target temperature TP, and the temperature deviation ΔT cannot be eliminated only by the temperature control using the temperature-sensitive coil spring 80, the temperature deviation ΔT is eliminated by performing feedback control. Therefore, the mixed hot and cold water temperature TC can always be controlled to the target temperature TP.

As shown in FIG. 12, many SMAs cause temperature hysteresis in which the spring constant is different between when the temperature rises and when the temperature falls. Therefore, when the temperature-sensitive coil spring 80 is made of SMA having this temperature hysteresis, proper temperature control may not be performed only by the temperature control using the temperature-sensitive coil spring 80. That is, the spring constant of the temperature-sensitive coil spring 80 changes in accordance with the rise of the mixed hot and cold water temperature TC to lower the mixed hot and cold water temperature TC. However, the spring constant does not change in accordance with the temperature drop in the same manner as when the temperature rises. This is the case where the mixed hot water temperature TC cannot be lowered to the target temperature TP or vice versa. However, in the present embodiment, since the mixed hot water temperature TC is feedback-controlled based on the output signal of the temperature sensor 110, the deviation of the mixed hot water temperature TC from the target temperature TP due to the temperature hysteresis can be eliminated.

In manufacturing a coil spring, generally, there is considerable variation in the spring constant of each product, and the spring constant of the coil spring has a relatively large manufacturing tolerance (±
At present, about 10% is allowed. Therefore, in the hot and cold water mixing apparatus 10 using two coil springs, the temperature-sensitive coil spring 80 and the second coil spring 90, when the temperature of the mixed hot and cold water is to be adjusted only by the temperature control by the temperature-sensitive coil spring 80, Due to the manufacturing tolerances of the coil springs, a considerable offset is generated for each mixing device, and it may not be possible to effectively perform appropriate temperature control. However, in this embodiment,
Since the mixed hot and cold water temperature TC is feedback-controlled based on the output signal of the temperature sensor 110, the offset due to the variation in the spring constant of the temperature-sensitive coil spring 80 and / or the second coil spring 90 is eliminated.

Similarly, a change in the spring constant of the temperature-sensitive coil spring 80 due to aging can be eliminated by feedback control.

In this embodiment, the temperature-sensitive coil spring 80
Although SMA is used for the above, any material that can set a predetermined spring constant at a predetermined temperature may be used instead of metal or plastic. The first and second springs need not be coil springs, but may be leaf springs.

Next, a second embodiment of the present invention will be described. The hot water mixing apparatus according to the second embodiment includes a preload adjusting mechanism 1 of the valve unit 15 according to the first embodiment shown in FIG.
The configuration is provided with a preload adjusting mechanism 200 described below instead of 00. Further, the operation of the second embodiment is the same as the processing routine at the start of hot water supply (FIG. 9), the processing routine at the time of target temperature change (FIG. 10), and the feedback control routine (FIG. 11) of the first embodiment. The configuration and operation of the preload adjusting mechanism 200 according to the second embodiment will be described below with reference to FIG.

FIG. 13 shows a preload adjusting mechanism 20 according to the second embodiment.
It is the schematic diagram which showed the outline of 0. Preload adjustment mechanism 200
Is a movable valve body 70 made of ferrite and a coil 21
0. The movable valve element 70 has a contact surface with the bore 62 coated with a fluororesin in order to reduce a contact friction force with the bore 62 of the housing 61. The coil 210 has an axis in the axial direction of the movable valve body 70 and is arranged so that the movable valve body 70 is the core. The coil 210 is connected to the electronic control unit 150, and generates a force in a direction in which the movable valve element 70 is sucked into the coil 210 by flowing a current, that is, a rightward force in FIG. 13. Thereby, the movable valve body 70 is connected to the temperature-sensitive coil spring 80 and the second
From the position where the spring force is balanced by the coil spring 90, the position is displaced to a new position where the balance includes the force due to the magnetic field. Therefore, by changing the current flowing through the coil 210, the movable valve 70 can be controlled to a desired position.

According to the hot water mixing apparatus of the second embodiment described above, the movable valve element 70 is driven by electromagnetic induction, so that the water tightness of the valve unit 15 can be maintained high. Also, since no motor is used to adjust the preload,
It has a simple structure and can increase reliability.

In the second embodiment, in order to save power, the temperature of the movable valve body 70 before tapping is stopped so that it stops at the position of the hot water / water mixture ratio at which the temperature is normally used (for example, 40 ° C.). Coil spring 80 and second coil spring 9
A configuration for adjusting 0 is also suitable. In this case, in the tapping start processing routine of FIG. 9, the preload is adjusted so that the mixed hot / cold water temperature TC becomes the default value TD.
Steps S100 to S150 become unnecessary. The movable valve element 7
It is sufficient to generate a magnetic field in the axial direction of the movable valve element 7.
A configuration in which a plurality of coils are arranged in parallel to the axial direction of the movable valve body 70 is also possible without arranging the coil 210 so that the center is 0. Further, a configuration in which only part of the movable valve body 70, for example, only the spring receivers 76 and 77, is made of ferrite or the like without using a material such as ferrite for the entire movable valve body 70 is also suitable.

Next, a third embodiment of the present invention will be described. The hot and cold water mixing apparatus of the third embodiment is different from the valve unit 15 of the first embodiment shown in FIG.
This is a configuration including a preload adjusting mechanism 300 described below instead of the preload adjusting mechanism 300. Further, the operation of the third embodiment is the same as the hot water supply start processing routine (FIG. 9), the target temperature change processing routine (FIG. 10), and the feedback control routine (FIG. 11) of the first embodiment. The configuration and operation of the preload adjusting mechanism 300 according to the third embodiment will be described below with reference to FIG.

FIG. 14 shows a preload adjusting mechanism 30 according to the third embodiment.
It is a schematic diagram which shows the outline of 0. This preload adjusting mechanism 30
In the case of 0, a heating element 302 capable of controlling the temperature by a signal from the electronic control device 150 is provided near the temperature-sensitive coil spring 80 for urging the movable valve element 70 in one direction. Since the heating element 302 raises the mixed hot and cold water temperature TC near the temperature-sensitive coil spring 80, the mixed hot and cold water temperature TC
The spring constant of the temperature-sensitive coil spring 80 is changed according to the temperature rise. When the spring constant changes, the spring force balance between the temperature-sensitive coil spring 80 and the second coil spring 90 is broken, and the movable valve body 70 is displaced to a new balance position. The spring constant of the temperature-sensitive coil spring 80 is determined by the temperature near the temperature-sensitive coil spring 80, and the temperature near the temperature-sensitive coil spring 80 is:
The amount of heat generated by the heating element 302, the temperature TC of the mixed hot water before contacting the amount of heat generated by the heating element 302, and the flow rate of the mixed hot water are determined. Therefore, when the flow rate of the mixed hot and cold water is constant, by changing the amount of heat generated by the heating element 302,
The movable valve element 70 can be driven to control the mixed hot and cold water temperature TC.

According to the hot water mixing apparatus of the third embodiment described above, since the preload adjusting mechanism 300 has no movable parts, the water tightness of the valve unit 15 can be maintained high. Also, since no motor is used to adjust the preload,
It has a simple structure and can increase reliability.

In the third embodiment, the heating element 302 is installed near the temperature-sensitive coil spring 80. However, the heating element 302 is in contact with the temperature-sensitive coil spring 80. Hot coil spring 8
A configuration in which the temperature of 0 is changed may be used. Further, the second coil spring 90 has the same S as the temperature-sensitive coil spring 80.
The heating element 302 is made of MA and the second coil spring 9
A configuration in which 0 is controlled independently of the mixed hot and cold water temperature TC is also suitable.

The embodiments of the present invention have been described above. However, the present invention is not limited to these embodiments and can be implemented in various modes without departing from the gist of the present invention. Of course.

[0059]

As described above, in the hot water mixing apparatus of the present invention, the temperature of the hot water mixture can be controlled using a spring made of a material whose spring constant changes according to the temperature within a predetermined temperature range. it can. Further, when a deviation occurs between the temperature of the hot and cold water mixture and the target temperature due to the balance between the spring forces of the first spring and the second spring at the temperature deviating from the target temperature, the preload adjustment is performed on the side to cancel the deviation. Since the means is controlled, the temperature of the hot and cold water mixture can be set as the target temperature. Further, when the first spring has temperature hysteresis, a difference in spring constant due to aging, and a characteristic error between lots, a deviation may occur between the temperature of the hot and cold water mixture and the target temperature due to these. Also in this case, since the preload adjusting means is controlled to cancel the deviation, the temperature of the hot and cold water mixture can be set as the target temperature.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a basic structure of a hot water mixing apparatus of the present invention.

FIG. 2 is a schematic view illustrating a hot water mixing apparatus 10 of the present invention.

FIG. 3 is a perspective view of the hot and cold water mixing apparatus 10 shown in FIG.

FIG. 4 is a foot fitting 11 for water supply which constitutes the hot water mixing apparatus 10;
FIG.

FIG. 5 is an enlarged sectional view of a valve unit 15 constituting the hot and cold water mixing apparatus 10.

6 is a structural diagram of a fixed disk 121 incorporated in the switching / water stop valve 120. FIG.

FIG. 7 is a structural view of a rotating disk 125 incorporated in the switching / water stop valve 120.

FIG. 8 is a block diagram showing an electrical configuration of a control system centering on the electronic control device 150.

FIG. 9 is a flowchart showing a hot water discharge start processing routine executed by CPU 150a of electronic control device 150.

FIG. 10 is a flowchart showing a target temperature change processing routine executed by a CPU 150a of the electronic control unit 150.

11 is a flowchart illustrating a feedback processing routine executed by a CPU 150a of the electronic control device 150. FIG.

FIG. 12 is a graph showing a relationship between a spring constant and a temperature of a temperature-sensitive coil spring 80 made of a shape memory alloy.

FIG. 13 is a schematic diagram showing an outline of a preload adjusting mechanism 200 by electromagnetic induction.

FIG. 14 is a schematic diagram schematically showing a preload adjusting mechanism 300 using a heating element.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Hot water mixing device 11 ... Water supply leg fitting 12 ... Hot water supply leg fitting 15 ... Valve unit 18 ... Control unit 20 ... Housing 21 ... Inlet 22 ... Water stop valve 23 ... Valve body 24 ... Guide part 25 ... Opening 26 ... End 27 Cap 28 Strainer 29 Outlet 30 Pressure control valve 31 Valve seat 32 Valve member 33 Skirt 34 Nut 35 Guide member 36 Bore 37 Secondary pressure chamber 40 Valve shaft 41 Spring Receiver 42 Cap 45 Metal bellows 46 Back pressure chamber 52 Water stop valve 58 Pressure introducing pipe 59 Outlet 60 Hot water mixing valve 61 Housing 62 Bore 63 Valve chamber 64 Hot water mixing chamber 70 Movable valve Body 71 ... Cylindrical part 72 ... Web 73 ... Opening 74 ... Retaining ring 75, 76, 77 ... Spring receiver 80 ... Temperature sensitive coil spring 85 ... Water inlet 86, 96 ... Annular passage 7 ... Water side valve seat 90 ... Second coil spring 95 ... Hot water inlet 97 ... Hot water side valve seat 100, 200, 300 ... Preload adjustment mechanism 101 ... End member 102 ... Movable spring receiver 103 ... Output shaft 104 ... Worm 105 ... Preload adjusting motor 106 ... O-ring 110 ... Temperature sensor 120 ... Switching / water stop valve 121 ... Fixed disk 122,123,126 ... Water discharge port 125 ... Rotating disk 127 ... Switching / water stop motor 130 ... Shower 131 ... Connection fitting 132 ... Shower hose 140 ... Callan 141 ... Connecting fitting 150 ... Electronic control device 150a ... CPU 150b ... ROM 150c ... RAM 150d ... Backup RAM 150e ... Temperature sensor input circuit 150f ... Switch input circuit 150g ... Motor drive circuit 150h ... Motor drive circuit 150i… LC Drive circuit 150j Constant voltage circuit 160 LCD 170 Panel operation unit 171,172 Switch 175 Shower selection switch 176 Callan selection switch 177 Water stop switch 180 Battery 210 Coil 302 Heating element M1 Preload adjustment Means M2 Temperature detecting means M3 Initial preload setting means M4 Electronic control means MV Hot water mixing valve

Continuation of front page (56) References JP-A-58-152984 (JP, A) JP-A-2-306318 (JP, A) JP-A-60-184113 (JP, U) JP-A-61-44062 (JP) , Y1) (58) Field surveyed (Int. Cl. ⁷ , DB name) G05D 23/00-23/32

Claims (2)

(57) [Claims] 1. A hot water mixing valve having a movable valve body for adjusting a hot water mixing ratio, and a material whose spring constant changes according to temperature in a predetermined temperature range, wherein a temperature of the hot water mixture flowing out of the mixing valve is determined. A first spring for urging the movable valve body in a direction in which the proportion of hot water is reduced with rising; a second spring for urging the movable valve body in a direction opposite to the direction; an adjustable preload adjustment means at least one of preload of the second spring, a temperature detecting means for detecting a temperature of the hot water mixture, and controls the preload adjusting means, said preload hot water mixture Initial preload setting means for setting an initial value corresponding to the target temperature; and, after the setting, if there is a deviation between the temperature detected by the temperature detecting means and the target temperature, the deviation is set on the side for canceling the deviation. Controlling the preload adjusting means. Gosuru and an electronic control unit, said preload adjusting means includes a temperature of the temperature of the first spring water
A hot and cold water mixing device that is a separately controlled heating means . 2. The hot and cold water mixing device according to claim 1, wherein the preload adjusting means is means for changing an effective length of the first or second spring.