JPH06331051A - Fixed flow valve with water temperature correction - Google Patents

Abstract

PURPOSE:To attain not only displaying an essential pressure adjusting function and water temperature correcting function but also decreasing a pressure drop value at a low cost, in a fixed flow valve with water temperature correction. CONSTITUTION:A valve element is formed of a coil-shaped spring 41 actuated to extend/contract in accordance with fluctuation of a pressure of fluid, to make a clearance between windings 43 of this coil-shaped spring 41 correspond to a passing hole area variable in accordance with fluctuation of the pressure of fluid. A spring load characteristic of the coil-shaped spring 41 is non-linearly set so as to almost fix a product of the passing hole area by the clearance 15 between the windings 43 of the coil-shaped spring 41 and a square root of fluid difference pressure with the coil-shaped spring 41 bordering. Further, the coil-shaped spring 41 is formed of SMA material which is a heat sensitizing responding member corresponding to change of a supply water temperature.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is mounted on a water supply side of a water heater or the like, and can supply the apparatus at a constant flow rate regardless of fluctuations in the supply pressure thereof, and can also change the temperature of the supply water. Accordingly, the present invention relates to a constant flow valve with a water temperature correction function for adjusting the amount of supplied water, and in particular, a coil spring made of a shape memory alloy is used as a thermoresponsive element for water temperature.

[0002]

^2. Description of the Related Art Generally, the supply pressure of tap water supplied to a house varies from 0.3 to 7.0 kg / cm ² . Possible causes of this are regional differences such as mountains and valleys, insufficient capacity of water supply pipes, and demand for supply. Further, for example, the hot water supply water heater is provided with a constant flow valve so that there is no problem even if the supply pressure of the tap water varies.

An example of a general structure of the constant flow valve is shown in FIG. 4 of Japanese Utility Model Publication No. 4-10450. In the constant flow valve, the liquid supplied from the liquid inlet 3 into the primary hydraulic chamber 12 between the intermediate portion of the tubular valve body 8 and the valve box 2 is indicated by the reference numerals in the drawings of the publication. Then, it passes through the proximal end chamber 1 and the secondary hydraulic chamber 13 in the tubular valve body 8, and then sequentially flows to the liquid outlet 4 via the orifice 6.

Such a constant flow valve is set when the differential pressure before and after the valve does not reach 1.0 to 1.5 kg / cm ² , as shown by the solid line in the pressure flow characteristic diagram of FIG. From the experimental results, it is known that the flow rate (20 l / min in the figure) is not satisfied. That is, in this case, in the area where the supply pressure of the tap water is 0.3 kg / cm ² which is the lower limit of the variation, the hot water heater cannot be used soundly, and the user is dissatisfied. .

Conventionally, as a means for improving such pressure loss on the low pressure side, the valve diameter is increased or two valves are provided as shown in Japanese Patent Publication No. 62-35574. As a result, the area of the passage hole of the valve portion is enlarged and the passage resistance value is reduced to deal with the problem.

Further, conventionally, a shape memory alloy (SMA; Shape Memory Alloy, hereinafter simply referred to as S) has been used as a water temperature thermosensitive element.
As a constant flow valve with water temperature correction using a coiled spring manufactured by MA), there is known a constant flow valve disclosed in JP-A-63-303281. The characteristic configuration is as follows, when the reference numerals in the drawings of the publication are also described. That is, in this constant flow valve with water temperature correction, the movable valve body V2 is biased by the SMA coil spring 1 against the fixed valve body V1 so as to be superposed, and a complicated flow path is provided. It has a structure.

[0007]

[Problems to be Solved by the Invention]
In the constant flow valve disclosed in FIG. 4 of Japanese Unexamined Patent Publication No. 10450, the method of increasing the valve diameter causes the valve housing itself to be large in size and costly. Further, as disclosed in Japanese Patent Publication No. 62-35574, the method of providing two valves complicates the valve structure and increases the cost.
However, there was a problem that the improvement effect was small.

In the conventional constant flow valve as shown in FIG. 4 of Japanese Utility Model Publication No. 4-10450 and Japanese Patent Publication No. 62-35574, there are many components in the first place, and the shape of the components is large. Is complicated, the man-hours for assembling parts and the man-hours for assembling are large, and the cost is high.
We could not supply an inexpensive constant flow valve. For this reason, there were places where the market could not continue to grow even though many fields of application could be expected.

Further, in the constant flow valve with a water temperature correction using the SMA coil spring disclosed in the above-mentioned Japanese Patent Laid-Open No. 63-303281, as described above, the structure thereof is complicated, and therefore the fluid passage resistance is increased. Was large, the pressure loss value was high, and it was a high-cost product.

By the way, the heat exchange capacity of the water heater is limited, and the hot water supply capacity of the water heater must be maintained. The stable supply of the fluid pressure on the water supply side and the stable supply of the fluid temperature of the supply water are required. In the constant flow valve, the former stable supply of fluid pressure can be achieved by the governor function, and the latter stable supply of fluid temperature is handled by the water temperature correction function.

Here, the water temperature of the supply water of a general tap water is
About 5 ° C in winter and about 25 ° C in summer, the temperature difference is 20 ° C. For this reason, if the temperature setting dial in the water heater is adjusted to winter, for example, it will become overheated in summer, and if it is adjusted to summer, it will be insufficiently overheated in winter, resulting in large fluctuations. Therefore, most of the conventional techniques in the constant flow valve with water temperature correction are
The control point is set in the winter, and the capacity that becomes overheated in the summer is dealt with by increasing the flow rate of the supplied water so that the hot water temperature becomes constant throughout the year, and the supply capacity is stabilized. Has been taken.

The present invention is based on the same idea, and its purpose is not only to exhibit the original pressure regulating function and water temperature correcting function, but also to reduce the above-mentioned pressure loss value. It enables sound use of hot water heaters in low-pressure areas where the supply pressure is 0.3 kg / cm ² or less, and the simplified structure reduces the number of parts and simplifies the shape of parts. It is to provide a constant flow valve with water temperature correction at a low cost at a low cost by significantly improving the processing man-hours and the assembly man-hours.

[0013]

In order to solve the above problems, the present invention is provided with a valve body which is installed in a water supply passage for a fluid and which makes a passage area of the fluid variable in accordance with a pressure variation of the fluid. A constant flow valve with a water temperature correcting function, which corrects the area of the passage hole of the valve body with an SMA material which is a heat sensitive element corresponding to a change in the supplied water temperature so that a predetermined flow rate corresponding to the supplied water temperature can be obtained. The valve element is formed of a coiled spring that expands and contracts in response to pressure fluctuations of the fluid,
The gap between the windings of the coiled spring is made to correspond to the passage hole area that is variable according to the pressure fluctuation of the fluid, and the passage hole area is defined by the gap between the windings of the coiled spring, and The spring load characteristic of the coil spring is set to be non-linear so that the product of the square root of the pressure difference of the fluid with the coil spring as a boundary is substantially constant, and the coil spring is connected to the supply water temperature. S corresponding to the change of
It is made of MA material.

[0014]

The coil-shaped spring forming the valve element expands and contracts according to the pressure fluctuation of the fluid, and the area of the passage hole due to the gap between the respective windings becomes variable according to the pressure fluctuation of the fluid. Moreover, the spring load characteristic of the coiled spring that forms the valve element is a non-linear characteristic in which the product of the area of the passage hole due to the gap between the windings and the square root of the differential pressure of the fluid across this is almost constant. For example, in a low-pressure area where the supply pressure of tap water is 0.3 kg / cm ² or less, generation of fluid passage resistance is small and pressure loss is very small.

When the water temperature changes, the spring load changes proportionally with the SMA coiled spring as the valve element, and the area of the passage hole due to the gap between the windings also increases / decreases proportionally. The amount of water supply also increases / decreases proportionally.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a constant flow valve with water temperature correction according to the present invention will be described below with reference to FIGS. FIG. 1 shows a first embodiment of a constant flow valve with water temperature correction according to the present invention, and is a vertical sectional side view showing a state before the start of use, and FIG. 2 is taken along the line AA in FIG. FIG. 4 is a cutaway plan view for explaining a pressure receiving area in which the valve housing and the like are shown in cross section, FIG. 3 is a vertical cross-sectional side view showing a stable state of flow rate control, and FIG.

First, FIGS. 1 to 4 show a first embodiment of the present invention. In FIG. 1 showing a state before the start of use of a constant flow valve 10 with a water temperature correction according to the first embodiment, 1
1 is a valve housing, 12 is a flow path, 13 is an inlet, 15 is an outlet, 2
Reference numeral 1 is a valve support plate, 23 is a through hole, 25 is a bearing cylinder, 31 is a spring receiving plate, 33 is a guide shaft, 35 is a snap ring, and 41 is a SMA coil spring that forms a valve body. The valve housing 11 has an inlet 13 at one end and an outlet 15 at the other end, with the tubular body serving as a flow path 12, and has a taper screw 14 provided on the outer circumference on the inlet 13 side and an outer circumference on the outlet 15 side. By the provided taper screw 16, for example, the taper screw 16 is connected to a water supply pipe line of a hot water supply water heater (not shown).

The outlet 15 in the intermediate portion 17 of the valve housing 11
On the side, the valve support plate 21 is formed so as to divide the flow path 12 at a right angle.
Are formed. A plurality of through holes 23, 23, ... Are formed in the valve support plate 21 in the circumferential direction thereof, and a bearing tubular body 25 extending to the outlet 15 side is formed in the center. The bearing hole 26 in the bearing cylinder 25 is formed by the valve support plate 21.
Has an opening on the upper surface of. A guide shaft 33 having a disk-shaped spring receiving plate 31 at the upper end is slidably and rotatably assembled in the bearing hole 26, and the lower surface of the spring receiving plate 31 and the upper surface of the valve supporting plate 21 are provided. Between the valve housing intermediate portion 17 and the step portion 22, a conical SMA coil-shaped spring 41 forming a valve body is provided.

That is, in the conical SMA coil-shaped spring 41 forming the valve body, the small diameter side is in contact with the lower surface of the spring receiving plate 31, and the large diameter side is in the step portion 22 on the upper surface of the valve supporting plate 21. The abutment ring 35 is fitted in the annular groove portion 34 formed at the end of the guide shaft 33 protruding from the bearing tubular body 25 toward the outlet 15 side in abutment and slightly compressed state. Thus, in the valve casing 11, a conical SMA that forms a valve body with the spring receiving plate 31 so as to close the flow passage 12 is formed.
A coil-shaped spring 41 is attached. The pressure of tap water flowing from the inlet 13 into the flow path 12, that is,
The primary-side pressure P1 is the cross section of the guide shaft 33 of the spring receiving plate 31 and the upper surface of each winding 43, 43, ... Of the conical SMA coil-shaped spring 41 forming the valve body (on the upper surface of the spring wire development length). (Corresponding) acts uniformly.

The pressure receiving area A for controlling the valve opening and closing of the constant flow valve 10 is the maximum in the range of the granular pattern shown in FIG. 2, and the SMA coil spring 41 is as shown in FIGS. 3 and 4. In addition, since the operation form of the winding 43 starts contacting from the large diameter side and is gradually shifted to the smaller diameter side as the displacement amount increases, it will be described later as shown in proportion in FIG. It decreases in a manner almost proportional to the passage hole area S. The constant flow valve 10 senses a change in water pressure by the pressure receiving area A as described above and responds to it. Here, the conical SMA coil-shaped spring 41 forming the valve body is shown in FIG.
As shown in FIG. 4, since the windings 43, 43, ... Are spirally formed toward the small diameter side so as to sequentially contact the inside of the large diameter side, one coil is wound at the maximum displacement. It becomes a disc shape.

3 and 4 are longitudinal side views showing a stable state of the flow rate control. As shown in FIG.
Windings 43, 43, 43 on the small diameter side of the coil-shaped spring 41 made of
43, ... Are not in contact with each other, and a gap 45,
45, 45, 45, ... This gap 45, 4
The total circumference of 5, 45, 45, ... Is the passage hole area S that controls the fluid at this stable time. Also, each winding 43, 4
In the contact portions of 3, ..., the leakage of fluid from the contact surfaces is required to be such that the function as a constant flow valve can be secured. Further, the valve support plate 21 has a backup function of the conical SMA coil spring 41 that forms the valve body during the displacement as described above. The fluid pressure changes from the primary pressure P1 to the secondary pressure P2 with the conical SMA coil-shaped spring 41 forming the valve body as a boundary.

The flow rate Q of the fluid is generally expressed by the following equation.

Q = αSV = αS√ (2g (P1−P2) / r) = αS√ (2gΔP / r) (1) where α is a coefficient, S is the area of the passage hole of the fluid, g is the acceleration of gravity, P1 is the primary pressure, P2 is the secondary pressure, r is the specific gravity of the fluid, V is the fluid velocity, and ΔP = P1-P2.

Since α, g, and r are coefficients and constants, when formula (1) is rearranged and the conditions for controlling the constant flow rate are searched, Q∝S√ΔP (2) Thus, the condition that the flow rate Q is constant is that the passage hole area S
And the product of the square root (√ΔP) of the differential pressure with the coiled spring 41 forming the valve body as a boundary is constant.

The balance between ΔP at one point of continuously changing ΔP and the coil-shaped spring 41 forming the valve body is expressed by the following equation.

ΔPA = KL = F (3) ΔP = F / A Q∝S√ (F / A) (4) where K is the spring constant of the spring 41, and A is the pressure received. The area, L represents the amount of displacement of the spring 41, and F represents the force generated by the displacement of the spring 41.

FIG. 7 is a characteristic diagram showing the changing state of the passage hole area S with respect to the displacement amount L of the conical coil-shaped spring 41 forming the valve body. It has a downward-sloping non-linear characteristic.
Therefore, in order to satisfy the above expression (2), the displacement load characteristic of the coiled spring 41 is set to "upward to the right" so that the "downward right" of the passage hole area S described above is achieved.
It can be seen that the characteristics should be corrected.

FIG. 8 is a characteristic diagram showing the changing state of the spring load F with respect to the displacement amount L of the conical coil spring 41 forming the valve body, and as shown in the figure, increases as it goes toward the close contact side. It has a non-linear characteristic that rises to the right. That is, this “upward rightward” characteristic can be obtained by using the conical coiled spring 41 as in the present embodiment.

However, on the actual surface, the pressure receiving area A is "downward to the right" like the passage hole area S. Therefore, in determining the displacement characteristic of the spring 41, the equations (3) and (4) are used. It is determined by confirming through an experiment in consideration of the passage hole area S while ensuring the relationship of.

The above-mentioned spring characteristics (the downward-sloping characteristic of the passage hole area S and the upward-sloping characteristic of the spring load F) can be realized by the conical coil spring 41, but as shown in FIG. General cylindrical coil spring 5 made of SMA
1 is also possible. In the case of the cylindrical SMA coil-shaped spring 51 forming such a valve body, each winding 53,
The pitch of 53, ... Is small on one end side of the cylindrical shape,
The pitch is unequal and the pitch is gradually increased to the maximum on the other end side. The pressure receiving area A in this case is
It is determined by the coil center diameter of the cylindrical SMA coil spring 51, and differs from the conical one. In the figure,
55 is a gap between the windings 53, 53. Also, the first
Cone-shaped SMA coil spring 4 which forms the valve body of the embodiment
Even in the case of 1, by freely adjusting the degree of the non-linear curve of the spring characteristics by changing the pitch for each of the windings 43, 43, .. It is possible to approach.

Next, the operation of the constant flow valve 10 provided with the conical SMA coil spring 41 forming the valve body of the first embodiment will be described.

In FIGS. 1, 3 and 4, when the use of a hot water heater (not shown) starts and a fluid flows at the inlet 13, a conical SM that forms a valve body with the spring receiving plate 31.
The tap water supply pressure acts on the pressure receiving area A formed by the upper surface of the A coil spring 41. As a result, the SMA coil spring 41 is pushed to change the state shown in FIG. 1 to the state shown in FIG.

That is, the SMA coil-shaped spring 41 starts the close contact from the large diameter side of the conical shape, the close contact progresses to the small diameter side, and one end is close to the fully closed state. Upon receiving the reaction force of the generated force F due to the displacement of the spring 41 itself, the spring 41 is pushed back toward the valve opening side. Then, the operation of pushing back to the valve closing side by the acting force of the pressure receiving area A is repeated, and the flow rate becomes stable at the set flow rate value. In reality, the repetition of this operation is completed instantly.

3 and 5 show the stable state. Further, when it is stable, it corresponds to the intermediate position in the characteristic diagram of FIG. In such a stable state, the above equation (2) is established, and the actual fluid is controlled and used according to the above equation (1).
Here, as already described, the supply pressure of the tap water, in fact, there is 0.3~7.0kg / cm ² and variations, constant in the low-pressure side (0.3kg / cm ²⁾ which is a problem Considering the state of the flow valve 10, the fact that the pressure acting on the pressure receiving area A is small means that the amount of displacement of the conical SMA coil spring 41 forming the valve body is small, and this state is It is expected that the state is close to the state of FIG.

As is apparent from FIG. 1, the winding gaps 45, 45, 45, 45, 4 of the SMA coil spring 41 are formed.
.. are sufficiently distributed over the respective windings 43, 43, 43, 43, 43, .. Therefore, the passage hole area S of the valve portion is such that the winding clearances 45, 45, 45, 45, 45, .. and its perimeter, the number is so large that it cannot be compared with the constant flow valve disclosed in FIG. 4 of Japanese Utility Model Publication No. 4-10450. This situation corresponds to the left side of the characteristic shown in FIG. Such a state on the low voltage side corresponds to the left side of the characteristic indicated by the dotted line in the characteristic diagram of FIG. Therefore,
The passage resistance of the fluid is small and the pressure loss is very small.

By the way, the SMA material, which is a thermosensitive element, has a characteristic that the lateral elastic modulus (G) of the material changes when the temperature changes, and it is known that this characteristic becomes linear in a constant temperature region. ing. Therefore, the spring load proportional to the lateral elastic coefficient also has a linear characteristic in the temperature range (see JP-A-63-303281).
(See FIG. 3 of the publication), it is widely used. The temperature range is easily determined by selecting the heat treatment temperature in the manufacturing process.

In the embodiment of the present invention, the SMA coil spring 41 is heat-treated on the extension side, and this shape is memorized. Therefore, the SMA coil spring 41
Has the property of undergoing a compressive deformation on the low temperature side and then recovering the stored original shape on the extension side when heated.

Here, it has already been described that the base point of the control of the water temperature correction function is in the winter season. However, where to set this base point is particularly important for the present invention in which the valve body corresponds to the coil spring 41. Is. Since the coil-shaped spring 41 is made of SMA material, the product of the passage hole area S and the square root (√ΔP) of the differential pressure of the fluid with the coil-shaped spring 41 as a boundary is substantially constant. The reason is that the temperature at which the spring load characteristic of the coil spring 41 is set non-linearly becomes a problem.

FIG. 8 shows S in the assembling relationship with the valve housing 11.
The spring load characteristic of the MA coil spring 41 is shown, and the curve shown by the solid line shows the characteristic at a predetermined constant temperature (T ° C) when the base point is set in the winter season. Is. Therefore, the hot water supply capacity of the water heater or the like can be guaranteed at a minimum with the constant flow valve 10 having the spring load characteristic shown by the solid line. The curve indicated by the one-dot chain line shows the characteristic at a water temperature (T1 ° C) slightly higher than T ° C, and the curve indicated by the two-dot chain line shows the characteristic at a higher water temperature (T2 ° C). It is a thing.

Next, the water temperature of the water supplied to the water heater changes from T1 to T2 during use, and the amount of hot water supplied increases or decreases due to the action of the SMA coil spring 41 that forms the valve body. Consider In addition, here, the equations (2), (3), and (4) are used. In each equation, Q is a control flow rate at a base point T ° C., S is a fluid passage hole area, ΔP = P1−P2 (differential pressure), A is a pressure receiving area, and K is a base point of an SMA coil spring 41. Spring constant of T ° C., L is displacement of SMA coil spring 41, F is SM
It is a spring load at the base point T ° C. of the coil spring 41 made of A.

In the present invention, as described above, since the valve body is supported by the SMA coil spring 41, the above (2)
In the expressions, (3), and (4), when the water temperature of the supply water changes, the above-mentioned F, S, K, and Q change, and so on. .

In FIG. 8, the diagram shown on the horizontal axis side of the spring load characteristic diagram is the SMA coil spring 41 and the spring receiving plate which form the valve element provided on the valve support plate 21 of the valve housing 11. 31
In order to facilitate understanding, the L
And spring height H, and SMA coil spring 4
The relationship between the free length of 1 and the set length is shown. here,
When the SMA coiled spring 41 operates to balance at the spring height H, and this H is constant and does not change, and the water temperature rises to T, T1, T2, as shown in the same figure, The spring load also changes to F, F1 and F2. In the following, the control flow rate at T1 ° C. is represented by Q1 and the control flow rate at T2 ° C. is represented by Q2.

Therefore, at T1 ° C., the equation (2) becomes Q1∝S√ΔP1, and from the equation (4), ΔP1
= F1 / A, so Q1∝S√ (F1 / A) In this formula, S and A are the conditions under which H does not change, so T
Since it does not change even in 1, the formula is summarized as follows: Q1∝S√F1 (5) Also, at T2 ° C, in the same manner as above, Q2∝S√ΔP2 ΔP2 = F2 / A Q2 ∝S√ (F2 / A) Q2∝S√F2 ・ ・ ・ (6) The spring load expansion ratio of the SMA coil spring 41 is α = F
Since it is 2 / F1, F2 = αF1 (7) By substituting this equation (7) into the equation (6) and extracting the flow rate, Q2∝S√ (αF1) is compared with the equation (5). Then, Q2∝Q1√α (8)

Therefore, it can be seen that the increase in the amount of hot water supplied when the supply water temperature changes from T1 to T2 is √α times that at T1. FIG. 9 shows the time course of these Q, Q1 and Q2. On the contrary, when the water temperature is lowered from T2 to T1, the spring load reduction rate is α = F2 / F1. Therefore, Q1 is reduced to √ (1 / α) of Q2.

Next, the second embodiment of the present invention shown in FIG. 6 will be described. The constant flow valve 60 with water temperature correction according to the second embodiment is of a type that is inserted into the water supply pipe line 61 and directly assembled.

That is, the valve support plate 71 is incorporated so as to divide the inside of the water supply pipe 61 at a right angle. This valve support plate 71
Is a plurality of through holes 73, 73, 73, as in the first embodiment.
The bearing cylinder 75 and the bearing hole 76 are provided, and the supporting cylinder 77 for stabilizing the water supply pipe 61 is integrally provided.
This support cylinder 77 is in contact with the upstream side step portion 62 in the water supply pipe 61, and a seal member 79 such as an O-ring is assembled in the annular groove 78 on the outer peripheral surface so as to be airtight with the water supply pipe 61. Relationship.

Then, similarly to the first embodiment, the guide shaft 83 having the spring receiving plate 81 is slidably and rotatably assembled in the bearing hole 76, and the spring receiving plate 8 is provided.
1 stepped portion 72 between the lower surface and the support cylinder 77 on the upper surface of the valve support plate 71
A conical SMA coil-shaped spring 91 forming a valve body is interposed between the two. A retaining ring 85 is fitted in an annular groove portion 84 at the end of the guide shaft 83 protruding from the bearing tubular body 75 to the downstream side, 93 is a winding wire, and 95 is a gap therebetween. In this way, the valve support plate 71 including the spring receiving plate 81 and the conical SMA coil-shaped spring 91 forming the valve body is directly assembled in the water supply pipe 61 so as to close the flow passage.

The constant-flow valve 60 with water temperature correction according to the second embodiment also has the same function as that of the first embodiment, and compared with the first embodiment, the valve casing. Since the body can be omitted, there is an advantage that the cost can be further reduced.

In the above embodiment, the constant temperature valve with water temperature correction installed in the water supply conduit of the hot water heater has been intended to stabilize the hot water temperature, but the constant temperature control with water temperature correction according to the present invention is intended. The use of the flow valve is not limited to this, and it is installed in the cooling water supply pipe line of the high temperature heat treatment furnace and the air compressor to stabilize the operation and save water, and further, to flush the toilet bowl and the like. It can be widely used by installing it in the water supply pipe of a cleaning device (ball tap, etc.) to save water.

In addition, the constant flow valve with water temperature correction according to the present invention is installed on the supply side of applicable equipment and devices,
If the product can be supplied inexpensively, it can be installed and used on the outlet side of equipment and devices. For example, as one example, in a general household, in addition to general hot water supply such as a kitchen, bath, shower, etc. by installing a large-scale hot water heater, a heating device that arranges a heat exchanger in each room to supply hot water. Are often used.

As described above, a problem when hot water is supplied to a large number of places using one hot water heater is the state of installation of each device and apparatus, that is, the distance from the hot water heater, Due to the difference in fluid resistance due to the difference in height, the number of joints, etc., there may be a difference in the hot water supply flow rate to each.
Therefore, if the constant flow valve with water temperature correction according to the present invention is provided at the inlet of each hot water supply pipe to stabilize the flow rate, the above-mentioned problem can be solved.

Further, the specific arrangement of the constant flow valve with water temperature correction according to the present invention, the kind of fluid for which the flow rate is to be controlled, etc. are arbitrary, and other specific detailed structures and the like can be appropriately changed. Of course,

[0053]

As described above, according to the constant flow valve with water temperature correction according to the present invention, for example, the pressure loss on the low pressure side of the supply pressure of tap water can be reduced to 0.2 kg / cm ² or less, Even in a low-pressure area where the supply pressure of tap water is 0.3 kg / cm ² , for example, in the case of a hot water heater, the set flow rate (20 l / min in the embodiment) can be sufficiently supplied. Therefore, not only can the water heater for hot water be used soundly, but also sufficient water can be used, so that the user can be satisfied.

Further, according to the present invention, the water supply amount can be corrected according to the change in the water temperature of the supplied water by a simple structure in which the coiled spring forming the valve body is made of the SMA material which is the heat sensitive element. Since it also has a governor (pressure regulating) function, it is possible to constantly stabilize the hot water temperature of the hot water supply such as a water heater regardless of time.

The constant flow valve with water temperature correction according to the present invention can simplify the structure of the valve by providing the coiled spring as a valve body with a constant flow control function.
Since the parts can also be simplified, mass production is possible and man-hours can be greatly reduced. Therefore, it is possible to inexpensively and widely provide a constant flow valve with a good water temperature correction.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view showing a first embodiment of a constant flow valve with water temperature correction according to the present invention, showing a state before the start of use.

FIG. 2 is a cutaway plan view for explaining a pressure receiving area in which a valve housing and the like are shown in a cross section along line AA in FIG.

FIG. 3 is a vertical sectional side view showing a stable state of flow rate control.

FIG. 4 is an enlarged view of part B in FIG.

FIG. 5 is a cutaway side view showing a modified example of an SMA coiled spring that forms a valve body.

FIG. 6 is a vertical sectional side view showing a second embodiment of the constant flow valve with water temperature correction according to the present invention, showing a state before the start of use.

FIG. 7 is a characteristic diagram of a passage hole area (pressure receiving area) of a valve body by the constant flow valve with water temperature correction according to the present invention.

FIG. 8 is a diagram illustrating a function against water temperature fluctuation by combining a coil-shaped spring portion made of SMA with a spring load characteristic diagram of a valve body by a constant flow valve with water temperature correction according to the present invention.

FIG. 9 is a pressure / flow rate characteristic diagram for comparing pressure loss between a constant flow valve with water temperature correction according to the present invention and a conventional constant flow valve.

[Explanation of symbols]

 10, 60 Constant flow valve with water temperature correction according to the present invention 11 Valve housing 12 Flow path 13 Inlet 15 Outlet 21,71 Valve support plate 22,72 Step portion 23,73 Through hole 25,75 Bearing tubular body 31,81 Spring Retaining plate 33,83 Guide shaft 35,85 Retaining ring 41,51,91 SMA coil spring 43,53,93 which forms a valve body Winding 45,55,95 Gap 61 Water supply conduit 62 Step portion 77 Support cylinder 79 Seal member

Claims (1)

[Claims] 1. A valve body, which is installed in a water supply channel for a fluid, and has a passage hole area for the fluid that is variable according to a pressure fluctuation of the fluid,
Further, it is a constant flow valve in which the area of the passage hole of the valve body is corrected by a shape memory alloy material which is a heat sensitive element corresponding to the change of the supply water temperature so that a predetermined flow rate corresponding to the supply water temperature can be obtained. The valve body is formed of a coil-shaped spring that expands and contracts according to the pressure fluctuation of the fluid, and the gap between the windings of the coil-shaped spring is variable according to the pressure fluctuation of the fluid. Corresponding to the hole area, the product of the passage hole area due to the gap between the windings of the coiled spring and the square root of the differential pressure of the fluid with the coiled spring as a boundary is substantially constant, A constant flow rate with water temperature correction, characterized in that the spring load characteristic of the coiled spring is set non-linearly, and the coiled spring is formed of the shape memory alloy material corresponding to the change of the supplied water temperature. valve.