JP2947120B2 - Automatic pressure regulating valve and hot water mixing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic pressure regulating valve for equalizing two fluids having different pressures, and a hot water mixing apparatus for adjusting a mixing ratio of hot water and water and mixing them at a set temperature. .

[0002]

2. Description of the Related Art A conventional automatic pressure regulating valve of this type (for example, Japanese Patent Laid-Open No. 60-215169) is shown in FIG. In the figure, 1 is a primary path of a first fluid, and 2 is a primary path of a second fluid. The first valve body 3 and the first valve seat 4, and the second valve body 5 and the second valve seat 6 reduce the primary pressure of the first and second fluid paths, respectively. 7 connects the first valve body 3 and the second valve body 5 to each other, and the secondary pressure of the first fluid in the secondary side passage 8 after the pressure is reduced by the first valve body 3 and the valve seat 4. , A piston that operates with a pressure difference between the secondary pressure in the secondary path 9 of the second fluid after the pressure is reduced by the second valve element 5 and the valve seat 6, and reference numeral 10 denotes the piston 7 and the piston 7. It is a sealing material provided between cylinders 11 provided on the outer periphery. Springs 12 and 13
The first valve body 3 and the second valve body 5 are provided to reduce the sliding resistance between the cylinder 11 and the piston.

The primary pressure in the primary path 1 of the first fluid and the primary pressure in the primary path 2 of the second fluid determine the pressure receiving area applied to the piston 7 and the first and second valve bodies 3 and 4. By making equal, the primary pressures cancel each other out, and only the pressure difference between the secondary pressure in the secondary passage 8 of the first fluid and the secondary pressure in the secondary passage 9 of the second fluid causes the piston 7 to move. Operate. When the balance of the secondary pressure is lost, the piston 7 moves due to the pressure difference, and accordingly, the first and second valve bodies 3,
The lift amount of No. 4 changes, thereby changing the pressure reduction ratio of the primary pressure to equalize the secondary pressure. In addition, the provision of the sealing material 10 allows the piston 7 and the cylinder 11
Therefore, springs 12 and 13 are provided on the first and second valve bodies 3 and 4 to reduce the sliding resistance at which the piston operates. The sealing material 10 seals so that there is no leakage between the first fluid and the second fluid.

[0004] Further, as shown in FIG. 13, there is a type in which the pressure is equalized without providing a seal material on the piston 7.

[0005]

However, in the above-mentioned conventional automatic pressure regulating valve, the sliding resistance of the piston 7 is large because the sealing material 10 slides on the cylinder 11, so that the secondary fluid of the first fluid and the second fluid is hardened. There have been problems in that a pressure difference occurs in the lateral pressure and the responsiveness deteriorates.

Further, since the hysteresis of the springs 12 and 13 affects the lift amount of the valve bodies 3 and 4, there is a problem that it is difficult to equalize the secondary pressures of the first fluid and the second fluid. .

Further, the sealing material 10 is completely
There is a possibility that dirt or scale may bite between the seal member 10 and the cylinder 11 to lock the piston 7 because it is in close contact with the piston 1.

If the piston 7 is not provided with a sealing material, dirt or scale will bite between the piston 7 and the cylinder 11 and the piston 7 is locked. Since a certain gap or more must be provided and a large gap cannot be provided to reduce the amount of leakage, dimensional accuracy is required for the diameter of the cylinder 11 and the diameter of the piston 7,
There is a problem that processing is difficult and processing cost is high.

Further, when the primary pressure of the first and second fluids is high, or when the pressure difference between the primary pressures of the first and second fluids is large, the leakage from the piston 7 and the cylinder 11 may occur. The amounts of the first fluid and the second fluid may be increased, and the mixing amount of the first and second fluids in the automatic pressure regulating valve may be increased.

Further, in the conventional hot / water mixing apparatus using the automatic pressure regulating valve as described above, since the equalization cannot be performed quickly, the primary side pressure fluctuates rapidly or the flow rate is changed by the flow rate regulating valve. In such a case, the temperature of the mixed hot water fluctuates, and overshoot and undershoot may occur due to a response delay until the mixing ratio of the hot and cold water is adjusted by the mixing valve.

The present invention has been made to solve the above problems, and
It is a first object of the present invention to provide an automatic pressure regulating valve which can perform accurate pressure regulation by reducing sliding resistance between a cylinder and an elastic sealing material, and in which a piston is not locked by dust or scale.

A second object of the present invention is to provide an automatic pressure regulating valve in which the piston does not lock due to dust or bite of the scale and the amount of leakage between the first fluid and the second fluid is small.

A third object of the present invention is to provide an automatic pressure control valve capable of improving responsiveness and performing more accurate pressure control by greatly reducing sliding resistance by sliding an elastic seal material and a piston. It is in.

A fourth object is to fix the elastic sealing material even when the pressure difference between the first fluid and the second fluid is large,
An object of the present invention is to provide an automatic pressure regulating valve capable of reliably sliding a piston with an elastic sealing material.

A fifth object of the present invention is to provide an automatic pressure regulating valve which can fix the elastic sealing material more reliably and can further reduce the sliding resistance between the elastic sealing material and the piston.

A sixth object is to provide an automatic pressure regulating valve capable of preventing sticking of the elastic sealing material to the piston and preventing adhesion of scale to the groove of the piston even when the piston is not driven for a long time. is there.

A seventh object of the present invention is to provide a hot water mixing apparatus having a small overshoot or undershoot without adjusting the hot water mixing ratio, even if the primary pressure fluctuates rapidly or the flow rate is changed by a flow control valve. Is to provide.

[0018]

In order to achieve the first object, an automatic pressure regulating valve according to the present invention comprises a first fluid path, a second fluid path, and a primary pressure of a first fluid path. A first valve body and a first valve seat for reducing the pressure, a second valve body and a second valve seat for reducing the primary pressure of the second fluid path, a first valve body and a second valve body. The piston is operated with a secondary pressure difference after decompression of the first fluid and the second fluid, a cylinder provided on the outer periphery of the piston, a groove provided in the piston, and a predetermined gap between the cylinder and the cylinder. And an elastic sealing material provided in the groove so as to form a gap.

In order to achieve the second object, an automatic pressure regulating valve according to the present invention is configured such that an elastic sealing material has a cylinder-side cross-sectional shape and a piston-side cross-sectional shape having a concave shape.

Further, in order to achieve the second object, the automatic pressure regulating valve of the present invention is configured such that a bead is provided on the cylinder side of the elastic sealing material.

To achieve the third object, an automatic pressure regulating valve according to the present invention comprises a first fluid path, a second fluid path,
A first valve body and a first valve seat for reducing the primary pressure of the first fluid path, a second valve body and a second valve seat for reducing the primary pressure of the second fluid path, A piston that is connected to one valve body and the second valve body and that operates with a secondary pressure difference after decompression of the first fluid and the second fluid, a cylinder provided on the outer periphery of the piston, and a piston provided on the piston, It comprises a groove having a width larger than the movable range in the axial direction of the piston, and an elastic sealing material provided in the groove.

In order to achieve the fourth object, an automatic pressure regulating valve according to the present invention comprises a first fluid path, a second fluid path,
A first valve body and a first valve seat for reducing the primary pressure of the first fluid path, a second valve body and a second valve seat for reducing the primary pressure of the second fluid path, A piston that is connected to the valve body and the second valve body and that operates with a secondary pressure difference after decompression of the first fluid and the second fluid, a cylinder provided on the outer periphery of the piston, and a piston provided on the piston. , A groove having a width greater than or equal to the axial movable range, an elastic sealing material provided in the groove, and a fixing groove for fixing the elastic sealing material to the cylinder.

In order to achieve the fifth object, an automatic pressure regulating valve according to the present invention is configured such that the cross-sectional shape of the elastic seal material on the cylinder side is the same as that of the fixed groove, and the cross-sectional shape on the piston side is an arc shape. It is.

In order to achieve the sixth object, the automatic pressure regulating valve according to the present invention is configured such that a groove provided in a piston is made of resin.

In order to achieve the second object, the automatic pressure regulating valve of the present invention has a structure in which a predetermined gap is provided between the elastic sealing material and the groove.

In order to achieve the seventh object, a hot water mixing apparatus according to the present invention comprises: an automatic pressure regulating valve; a mixing valve provided downstream of the automatic pressure regulating valve for adjusting a mixing ratio of hot water and water; A flow control valve for closing the mixed fluid and controlling the flow rate is provided downstream of the valve.

[0027]

According to the automatic pressure regulating valve of the present invention, a predetermined gap is provided between the cylinder and the elastic sealing material, so that the sliding resistance of the piston is reduced and accurate pressure regulation can be performed. At the same time, dirt and scale can pass through the predetermined gap without penetrating, and the piston is not locked, so that a decrease in the pressure regulation function can be prevented. Further, even when the first and second fluids are at a high pressure, the elastic seal material is crushed in the radial direction of the piston by the primary pressure of the first fluid and the second fluid, so that the predetermined gap becomes small and the amount of leakage increases. Can be suppressed.

Further, in the automatic pressure regulating valve of the present invention, since the elastic sealing member is easily deformed in the radial direction of the piston by the above-described configuration, the safety against locking of the piston due to dust or scale biting can be improved. Things.

Further, in the automatic pressure regulating valve of the present invention, since the bead portion is easily crushed in the radial direction of the piston by the primary pressure of the first fluid and the second fluid by the above-described configuration, the first and second beads are easily crushed. When the fluid has a high pressure, the predetermined gap becomes smaller, and the increase in the amount of leakage can be further suppressed.

In the automatic pressure regulating valve according to the present invention, the sliding area is reduced by sliding the elastic sealing material with the piston, so that the sliding resistance can be greatly reduced, and the pressure can be accurately regulated. And responsiveness of pressure regulation can be improved.

Further, the automatic pressure regulating valve of the present invention has the above-described structure, and the elastic sealing material is fixed by the fixing groove and moves even when the primary pressure difference between the first fluid and the second fluid is large. Therefore, the sliding resistance can be reduced significantly.

In addition, in the automatic pressure regulating valve of the present invention, the fixing groove and the elastic sealing material have the same shape due to the above configuration, so that the elastic seal can be fixed more reliably and the arc of the elastic sealing material can be formed. Because of the shape, the sliding resistance can be further reduced.

Further, the automatic pressure regulating valve of the present invention can prevent the elastic seal material from sticking to the piston and reduce the adhesion of the scale to the piston, thereby preventing the pressure regulating function from deteriorating.

Further, in the automatic pressure regulating valve of the present invention, a predetermined gap is provided between the piston and the elastic seal material by the above-described structure, so that the sliding resistance of the piston is reduced and accurate pressure regulation can be performed. In addition to this, dirt and scale can pass through the predetermined gap without penetrating, and the piston is not locked, so that a decrease in the pressure regulation function can be prevented. Further, even when the first and second fluids are at high pressure, the elastic sealing material is crushed in the radial direction of the piston by the primary pressure of the first fluid and the second fluid, and the area of the gap can be reduced. The amount of leakage between the first fluid and the second fluid can be reduced.

Further, the hot water mixing apparatus of the present invention has the above-mentioned structure, and even if the primary pressure fluctuates rapidly or the mixed hot water quantity is changed by the flow rate control valve, the secondary pressure is immediately equalized by the automatic pressure regulating valve. , The fluctuation of the mixed hot water temperature is prevented, and the occurrence of overshoot and undershoot due to a response delay until the mixing ratio of the hot water is adjusted by the mixing valve is prevented.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a configuration diagram of a pressure equalizing valve 14 which is an automatic pressure regulating valve according to a first embodiment of the present invention, and FIG. 2 is an enlarged view of a portion A in FIG. In the figure, 15 is a water supply pipe as a first fluid path, and 16 is a hot water pipe as a second fluid path, and supplies water or hot water to the pressure equalizing valve 14, respectively. Reference numeral 17 denotes a piston that connects the first valve body 18 and the second valve body 19 and is set so as to be movable in a cylinder 18 provided on the outer periphery of the piston 17. The first valve body 19 and the second valve body 20
In accordance with the lift amount of the first valve seat 21 and the second valve seat 22 provided on the primary side 8, the primary pressures of the water and the hot water are respectively reduced, and the secondary passages of the outflow passages 23 and 24 for the water and the hot water are reduced. The lateral pressure is equalized. A groove 26 for setting the elastic seal material 25 is provided at the center of the piston 17, and a predetermined amount is provided between the outer peripheral surface of the elastic seal material 25 set in close contact with the piston 17 and the cylinder 18. Gaps are created. The valve body-side pressure receiving area of the groove portion 26 and the primary pressure side pressure receiving areas of the first valve body 19 and the second valve body 20 are substantially the same in order to eliminate the influence of the primary pressure. Guide portions 27 and 28 are provided to prevent the shaft of the piston 17 from being twisted. Reference numeral 29 denotes an insertion hole for inserting the piston 17 at the time of assembly.
After the 7 is inserted, the plug 30 provided with the guide portion 27 is screwed.

The operation of this embodiment with the above configuration will be described. In consideration of the force applied to the piston 17, the influence of the primary pressure in the water supply pipe 15 and the hot water supply pipe 16 depends on the pressure receiving area on the valve body side of the first valve body 19 and the second valve body 20 and the groove 26 of the piston 17. Because they are equal, they can be offset. Therefore, the piston 17 is provided with the outflow passage 23 for hot water and water,
24 is actuated by the force exerted on the first valve element 19 and the second valve element 20 by the secondary pressure (namely, the pressure difference between the secondary pressures in the outflow passages 23 and 24). Since the secondary-side pressure receiving areas of the valve element 20 are equalized, the operation stops when the secondary-side pressures of hot water and water become equal. That is,
When the pressure balance of the secondary pressure is lost, the piston 17 moves due to the pressure difference, and the lift of the first valve element 19 and the second valve element 20 changes accordingly, thereby changing the rate of reduction of the primary pressure. , And equalizing the secondary pressure.

At this time, if the piston 17 has sliding resistance, the piston 17 does not operate until a force exceeding the sliding resistance is applied to the piston 17. That is, a pressure difference corresponding to the sliding resistance occurs in the secondary pressure. However, since a gap is provided between the elastic sealing material 25 and the cylinder 18, almost no sliding resistance is generated, and the secondary pressure can be surely equalized.

Since a gap is provided between the elastic sealing material 25 and the cylinder 18, when the pressure difference between the primary side pressures is large, the dust and the scale are changed from the higher primary pressure to the lower primary pressure together with the fluid. It passes through the gap between 25 and the cylinder 18. At this time, dust and the like larger than the gap temporarily accumulate in the gap, but when the piston 17 operates, the elastic sealing material 25 is deformed, and the dust and the like pass through the gap, so that dust is accumulated in the gap. Therefore, the piston 17 is not locked due to clogging of dust or the like.

Since a gap is provided between the elastic sealing material 25 and the cylinder 18, a slight amount of leakage occurs between hot water and cold water. FIG. 3 shows the relationship between the primary pressure and the amount of leakage from the piston at this time. In the case of a cylinder that does not use a sealing material, the amount of leakage increases in accordance with the pressure and the temperature of the hot water decreases, which may hinder use at high pressure. However, in the present embodiment, the elastic seal material 25 has a shape shown by a solid line in FIG. 2 under a low pressure, and almost the same leakage occurs. However, at a high pressure, the elastic seal material 25 is shown by a dotted line due to the primary pressure. It is deformed into a shape, and the gap between the elastic sealing material 25 and the cylinder 18 is reduced, so that the leakage amount is reduced. Therefore, the elastic sealing material 25
By setting the gap between the cylinder and the cylinder 18, the amount of leakage can be reduced to a predetermined amount or less. The elastic sealing material 25
The groove 26 and the groove 26 are in close contact with each other so that sealing is performed, so that there is no leakage between the elastic sealing material 25 and the groove 26.

As described above, according to this embodiment, since a gap is provided between the elastic sealing material 25 and the cylinder 18, no sliding resistance is generated between the elastic sealing material 25 and the cylinder 18. In addition, there is an effect that the secondary side pressure can be surely equalized. In addition, since the elastic seal material 25 is used, when the piston 17 operates, the elastic seal material 25 is deformed, dust and the like pass through the gap, and no dust is accumulated in the gap, and the piston 17 is There is an effect that locking is not performed due to clogging of dust or the like. Further, even in the case of high pressure, the elastic sealing material 25 is deformed by the primary pressure,
Since the gap between the elastic seal member 25 and the cylinder 18 is reduced, the amount of leakage can be reduced to a predetermined amount or less.

The sectional shape of the elastic sealing material 25 is shown in FIG.
Similar effects can be obtained by forming a bead 25b on the piston 17 side and the cylinder 18 side like the elastic seal material 25a shown in FIG. In addition, even if the piston 17 is twisted or a considerably high pressure is applied, even if the elastic sealing material 25
5b is in contact with the cylinder 18, so that the contact area does not increase, and the sliding resistance of the piston 17 can be reduced. Further, a bead 25b is provided on the cylinder 18 side.
Is provided, the fluid resistance between the hot water and the hot water is increased by the elastic sealing material 25a, so that the leak amount between the hot water and the hot water can be further reduced.

FIG. 5 is a cross-sectional view of the elastic sealing material 25.
When the inverted V-shape (the cylinder side is made convex and the piston side is made concave) like the elastic seal material 25c shown in FIG. Since 25c is more easily deformed, the effect of further improving safety against locking due to clogging of the piston 17 with dust or the like can be obtained.

FIG. 6 is a view showing the construction of a pressure equalizing valve 31 which is an automatic pressure regulating valve according to a second embodiment of the present invention. FIG. 7 is an enlarged view of a portion B in FIG. Regarding 31, only differences from the configuration of the equalizing valve 14 in FIG. 1 will be described. A groove 32 larger than the movable range of the piston 17 is provided at the center of the piston 17 with a resin. Even when the piston 17 is operated, the fixed groove 33 of the cylinder 18 is set with a predetermined gap from the groove 32. The elastic sealing material 34 is prevented from hitting the piston 17 (that is, the side surface 35 of the groove 32 on the elastic sealing material 34 side is
7 does not come into contact with the elastic seal member 34 even when it operates. ).
The shape of the elastic sealing material 34 on the cylinder 18 side is
And the elastic seal member 34 is difficult to move due to the pressure difference of the primary side pressure. The shape of the elastic seal member 34 on the piston 17 side is a circular arc so that there is almost no sliding resistance even when the elastic seal member 34 and the piston 17 abut.

With respect to the operation of the present embodiment in the above configuration, only differences from the first embodiment will be described. Piston 17
, The piston 17 does not operate until a force exceeding the sliding resistance is applied to the piston 17. That is, a pressure difference corresponding to the sliding resistance occurs in the secondary pressure. However, since a gap is provided between the elastic sealing material 34 and the groove 32, almost no sliding resistance occurs,
The secondary side pressure can be reliably and quickly equalized. Piston 17
Even when the piston abuts against the elastic seal material 34 due to shaft deviation or the like, the shape of the piston side is an arc, and the groove 32 of the piston 17
Is a resin, there is almost no sliding resistance.

Since the cross-sectional area of the gap can be made smaller than that in which a gap is provided between the cylinder 18 and the elastic sealing material, the amount of leakage can be further reduced. FIG. 8 shows the relationship between the primary pressure and the amount of leakage from the piston at this time. At low pressure, the elastic sealing material 34, which had the shape shown by the solid line in FIG. 7, is deformed to the shape shown by the dotted line due to the primary pressure at high pressure, and the gap between the elastic sealing material 34 and the piston 17 is further reduced. Become. Therefore, even if the primary side pressure becomes high, the amount of leakage decreases.

As described above, according to this embodiment, the groove 32 larger than the movable range of the piston 17 is provided at the center of the piston 17 and the groove 32 and the elastic sealing material 3
Since the gap is provided between the elastic seal member 4 and the elastic seal member 34, the sliding resistance does not occur between the elastic seal member 34 and the groove 32, and the secondary pressure can be reliably and quickly equalized. Further, since the gap area between the groove 32 and the elastic sealing material 34 can be further reduced, the amount of leakage between hot water and water can be further reduced. Further, since the shape of the elastic seal member 34 on the cylinder 18 side and the shape of the fixed groove 33 are the same, even if the pressure difference between the primary side pressures is large, the elastic seal member 34 does not move and the pressure can be reliably equalized. In addition, piston 17
Even when the piston abuts against the elastic seal member 34 due to shaft deviation or the like, the shape of the piston side is an arc and the groove 3 of the piston 17
Since 2 is a resin, almost no sliding resistance occurs.
Further, since the groove 32 is made of resin, it is possible to prevent the scale from adhering to the groove 32, and thus it is possible to improve the durability.
Further, when the piston 17 is actuated, the elastic sealing material 34 is deformed, dust and the like pass through the gap, and the dust does not accumulate in the gap. in addition,
Since the amount of leakage between hot and cold water is small, and there is no possibility that the piston 17 is locked due to clogging of dust or the like, the allowable dimensional tolerance of the gap between the groove 32 and the elastic sealing material 34 can be widened, and the processing cost can be increased. Can be reduced.

In this embodiment, a predetermined gap is provided between the piston 17 and the elastic seal member 34. However, even if a predetermined gap is not provided between the piston 17 and the elastic seal member 34, the sliding area can be increased. Is considerably reduced, and the sliding resistance can be reduced, so that there is no leakage between hot and cold water, and a pressure equalizing valve with good responsiveness can be supplied.

FIG. 9 is a block diagram of a hot and cold water mixing apparatus 36 showing a third embodiment of the present invention, and FIG. 10 is an enlarged view of a portion C in FIG. 9, which is different from the configuration of the second embodiment. I will explain only. An X-ring 37, which is an elastic sealing material, is set in the fixed groove 33 of the cylinder 18 so as to form a predetermined gap with the groove 32. Here, the side surface 35 of the groove 32 does not hit the X ring 37 even when the piston 17 operates. The shape of the fixing groove 33 is rectangular,
The configuration is such that the X ring 37 is disengaged from the fixing groove due to the pressure difference of the primary side pressure and does not move.

Numeral 38 denotes a mixing valve capable of mixing the hot water and water equalized by the equalizing valve 31 at an arbitrary ratio, and 39 denotes a mixed hot water temperature for detecting the temperature of the mixed hot water mixed by the mixing valve 38. It is a detecting means. Numeral 40 denotes control means for controlling the mixing ratio of the hot and cold water in the mixing valve 38. The control means 40 controls the mixing ratio of the hot and cold water in the mixing valve 38 so that the temperature detected by the mixing hot water temperature detecting means 39 becomes equal to a preset temperature. Is controlling. Reference numeral 41 denotes a flow rate control valve provided on the downstream side of the mixing valve for controlling water shutoff and flow rate, and adjusts the amount of mixed hot water from the hot water outlet terminal 42.

With respect to the operation of the present embodiment in the above configuration, only differences from the second embodiment will be described. X ring 37
Since there is a gap between the groove and the groove 32, there is almost no sliding resistance, and even if the primary pressure of hot water or water fluctuates rapidly, the secondary pressure is reliably and quickly equalized. . At low pressure, the X-ring 37, which had the shape shown by the solid line in FIG. 10, is deformed into the shape shown by the dotted line due to the primary pressure at the time of high pressure, and the gap between the X-ring and the piston 17 is further reduced. Therefore, even if the primary side pressure becomes high as shown in FIG. 8 in the second embodiment, the amount of leakage between the hot water and the water decreases, so that the temperature of the hot water supplied to the mixing valve 38 decreases. Therefore, a high-temperature mixed hot water can be reliably obtained. The X ring 37 and the fixing groove 33 are in close contact with each other, and are securely sealed.

The hot water and the water equalized by the equalization valve 31 are supplied to the mixing valve 38, respectively. Control means 40
Adjusts the mixing ratio of hot and cold water in the mixing valve 38 so as to reduce the deviation between the preset temperature and the temperature detected by the mixed hot water temperature detecting means 39. That is, the detected temperature and the mixed hot water temperature are made to match by feedback control. The mixed hot water mixed to the set temperature by the mixing valve 38 is adjusted to the set flow rate by the flow rate control valve 41 and supplied from the hot water outlet terminal 42.

In general, when there is no pressure equalizing valve, if the primary pressure of hot water or water changes abruptly, the temperature of the mixed hot water changes abruptly. Also, when the flow rate is largely changed by the flow rate control valve 41, the temperature of the mixed hot water also rapidly changes because the primary pressure and the secondary pressure fluctuate. After the change in the hot water temperature is detected by the mixed hot water temperature detecting means 39, the mixing ratio of the hot water and the hot water is adjusted by the mixing valve 38, so that an overshoot or an undershoot as shown by a dotted line in FIG. 9 has occurred. Further, even when the pressure equalizing valve 31 is provided, if the sliding resistance is large and the response is poor, the pressure equalization is not performed quickly. In addition, the delay caused overshoot or undershoot. However, a gap is provided between the X ring 37 and the groove 32 as in the present embodiment,
By reducing the sliding resistance, the secondary pressure is reliably and promptly equalized, so that there is no need to change the mixing ratio of hot and cold water by the mixing valve 38, and as shown in FIG. No shoot occurs.

It is to be noted that overshooting or undershooting at the time of changing the set temperature can be prevented by reliably and quickly equalizing the secondary pressure.

As described above, according to the present embodiment, the groove 32 larger than the movable range of the piston 17 is provided at the center of the piston 17, and the gap is provided between the groove 32 and the X ring 37. , X ring 37 and groove 32
The secondary side pressure can be reliably and promptly equalized without generating any sliding resistance between them. Therefore, even if the primary pressure suddenly changes or the flow rate is changed by the flow rate control valve 41, there is no need to adjust the mixing ratio of hot and cold water by the mixing valve 38, and almost no overshoot or undershoot occurs. Is obtained. Further, even if the primary side pressure becomes high, the gap between the X ring 37 and the piston 17 is reduced by deforming the X ring 37, and the amount of leakage between hot and cold water is reduced. The temperature of the supplied hot water does not decrease and a high-temperature mixed hot water can be reliably obtained.

The same effect can be obtained by using the equalizing valve shown in the first and second embodiments as the equalizing valve 31 of the hot and cold water mixing device as in the third embodiment. .

[0058]

As described above in detail, the automatic pressure regulating valve of the present invention has a predetermined gap between the cylinder and the elastic sealing material, so that the sliding resistance of the piston is reduced and accurate pressure regulation is achieved. This can be performed, and dirt and scale can pass through the predetermined gap without digging into the gap, and the piston is not locked. Further, even when the first and second fluids are at high pressure, the elastic sealing material is crushed in the radial direction of the piston by the primary pressure of the first and second fluids, so that an increase in the amount of leakage can be suppressed.

In the automatic pressure regulating valve of the present invention, the elastic seal material has a convex section on the cylinder side and a concave shape on the piston side. In addition to improving the safety of locking the piston due to biting of the scale or the scale, the increase in the amount of leakage can be suppressed even when the first and second fluids are at a high pressure.

Further, in the automatic pressure regulating valve of the present invention, since the bead is provided on the cylinder side of the elastic sealing material, when the first and second fluids are at a high pressure, the bead portion is formed by the first fluid and the second fluid. The primary pressure of the fluid is likely to be crushed in the radial direction of the piston, and the predetermined gap can be made smaller. That is, the amount of leakage between the first and second fluids can be reduced.

In the automatic pressure regulating valve of the present invention, the sliding area is reduced by sliding the elastic sealing material with the piston, so that the sliding resistance can be greatly reduced and accurate pressure regulation can be performed. The responsiveness of pressure regulation can be improved.

Further, in the automatic pressure regulating valve of the present invention, since the fixing groove is provided in the cylinder and the elastic sealing material is fixed, even if the pressure difference between the primary pressures of the first fluid and the second fluid is large, the elastic pressure can be reduced. The sealing material does not move, and the sliding resistance can be reduced significantly.

In addition, in the automatic pressure regulating valve of the present invention, since the shape of the fixing groove and the shape of the elastic sealing material are the same, it is possible to more reliably fix the elastic seal and the circular shape of the elastic sealing material. In addition, the sliding resistance can be further reduced.

In the automatic pressure regulating valve of the present invention, since the groove is made of resin, it is possible to prevent the elastic seal material from sticking to the piston and to reduce the adhesion of scale to the piston. Therefore, it is possible to prevent a decrease in the pressure regulation function when not used for a long period of time, and to improve the durability performance.

Further, in the automatic pressure regulating valve of the present invention, since a predetermined gap is provided between the piston and the elastic seal material, the sliding resistance of the piston is reduced, and accurate pressure regulation can be performed. In addition, even if the predetermined gap is clogged with dirt or scale, the elastic sealing material is deformed, so that the dirt or scale can pass through the gap and the piston is not locked, so that a decrease in the pressure regulation function can be prevented. . Further, even when the first and second fluids are at high pressure, the elastic sealing material is crushed in the radial direction of the piston by the primary pressure of the first fluid and the second fluid, and the clearance area is reduced. And the amount of leakage between the second fluid and the second fluid can be reduced. In addition, the amount of leakage between the first fluid and the second fluid is small, and there is no possibility that the piston is locked due to clogging or the like. Therefore, the dimensional tolerance of the gap between the groove 32 and the elastic seal member 34 is allowable. And the processing cost can be reduced.

In addition, the hot and cold water mixing apparatus of the present invention is provided with an automatic pressure regulating valve for reducing the sliding resistance of the piston, a mixing valve for adjusting the mixing ratio of hot and cold water, and a flow control valve for adjusting the flow rate of the mixed hot water. Therefore, even when the primary pressure fluctuates rapidly or the flow rate is changed by the flow control valve, the secondary pressure can be immediately equalized by the automatic pressure control valve to prevent the fluctuation of the mixed hot water temperature. In addition to this, it is possible to prevent overshoot and undershoot due to response delay until the mixing ratio of hot water and water is adjusted by the mixing valve. Also, even if the primary pressure becomes high,
Since the amount of leakage between the hot water and the hot water is reduced by the deformation of the elastic sealing material, the temperature of the hot water supplied to the mixing valve does not decrease, and a high-temperature mixed hot water can be reliably obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view of an automatic pressure regulating valve showing a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a portion A of the automatic pressure regulating valve.

FIG. 3 is a characteristic diagram showing a relationship between a primary pressure and a leakage amount between fluids in the automatic pressure regulating valve.

FIG. 4 is an enlarged sectional view of a part A using another elastic sealing material in the automatic pressure regulating valve.

FIG. 5 is an enlarged sectional view of a part A using another elastic sealing material in the automatic pressure regulating valve.

FIG. 6 is a sectional view of an automatic pressure regulating valve showing a second embodiment of the present invention.

FIG. 7 is an enlarged sectional view of a portion B of the automatic pressure regulating valve.

FIG. 8 is a characteristic diagram showing a relationship between a primary pressure and a leakage amount between fluids in the automatic pressure regulating valve.

FIG. 9 is a sectional view of a hot water mixing apparatus showing a third embodiment of the present invention.

FIG. 10 is an enlarged sectional view of a portion C of the hot water mixing apparatus.

FIG. 11 is a characteristic diagram showing mixed hot water temperature in the hot water mixing apparatus.

FIG. 12 is a sectional view of a conventional automatic pressure regulating valve.

FIG. 13 is a sectional view of another conventional automatic pressure regulating valve.

[Explanation of symbols]

 14 pressure equalizing valve (automatic pressure regulating valve) 15 water supply pipe (first fluid path) 16 hot water supply pipe (second fluid path) 17 piston 18 cylinder 19 first valve element 20 second valve element 21 first Valve seat 22 Second valve seat 25 Elastic sealing material 25a Elastic sealing material 25b Bead 25c Elastic sealing material 26 Groove 31 Equalizing valve (automatic pressure regulating valve) 32 Groove 33 Fixed groove 34 Elastic sealing material 37 X-ring (Elastic sealing material) ) 38 Mixing valve 41 Flow control valve

Claims (9)

(57) [Claims] 1. A first fluid path, a second fluid path, a first valve body and a first valve seat for reducing a primary pressure of the first fluid path, and the second fluid path. A second valve body and a second valve seat for reducing the primary pressure, and a secondary after decompression of the first fluid and the second fluid connected to the first valve body and the second valve body. An automatic piston comprising a piston that operates by a pressure difference, a cylinder provided on the outer periphery of the piston, a groove provided in the piston, and an elastic sealing material provided in the groove so that a predetermined gap is formed between the cylinder and the piston. Pressure regulating valve. 2. The automatic pressure regulating valve according to claim 1, wherein the cross-sectional shape of the elastic sealing material is a convex shape on the cylinder side and a concave shape on the piston side. 3. The automatic pressure regulating valve according to claim 1, wherein a bead is provided on the cylinder side of the elastic sealing material. 4. A first fluid path, a second fluid path, a first valve body and a first valve seat for reducing a primary pressure of the first fluid path, and the second fluid path. A second valve body and a second valve seat for reducing the primary pressure, and a secondary after decompression of the first fluid and the second fluid connected to the first valve body and the second valve body. A piston that operates with a pressure difference, a cylinder provided on the outer periphery of the piston, a groove provided on the piston and having a width greater than or equal to an axial movable range of the piston,
An automatic pressure regulating valve comprising an elastic sealing material provided in the groove. 5. A first fluid path, a second fluid path, a first valve body and a first valve seat for reducing a primary pressure of the first fluid path, and the second fluid path. A second valve body and a second valve seat for reducing the primary pressure of the first fluid and the second valve body connected to the first valve body and the second valve body. A piston that operates at the next pressure difference, a cylinder provided on the outer periphery of the piston, and a piston provided on the piston,
An automatic pressure regulating valve comprising a groove having a width greater than or equal to the axial movable range of the piston, an elastic sealing material provided in the groove, and a fixing groove for fixing the elastic sealing material to the cylinder. 6. The automatic pressure regulating valve according to claim 3, wherein the cross-sectional shape of the elastic sealing material is the same as that of the fixing groove on the cylinder side and the arc shape is on the piston side. 7. The automatic pressure regulating valve according to claim 3, wherein a resin is used for a groove provided in the piston. 8. The automatic pressure regulating valve according to claim 3, wherein a predetermined gap is provided between the elastic sealing material and the groove. 9. A mixing valve provided downstream of the automatic pressure regulating valve for adjusting the mixing ratio of hot water and water, and a flow regulating valve downstream of the mixing valve for closing and controlling the flow rate of the mixed fluid. Item 9. The hot and cold water mixing device according to any one of Items 1 to 8.