JP4889380B2 - Heating system - Google Patents

Description

  The present invention relates to a heating system that generates hot water by heating cold water with a heating fluid such as steam.

Conventionally, a hot water supply apparatus that generates hot water by heating cold water with steam is known. As shown in FIG. 6, the heating system in this hot water supply apparatus generates hot water M by heating cold water C with heat of a heating fluid S such as steam by a heat exchanger 60, and is supplied from a water supply source WA. A cold water pipe 61 that leads the cold water C to the heat exchanger 60 and a heating fluid pipe 62 that is connected to an external heating fluid supply source VA and leads the heating fluid S from the heating fluid supply source VA to the heat exchanger 60. And a hot water pipe 63 for deriving the hot water M generated by heat exchange between the cold water C and the heating fluid S in the heat exchanger 60. The heating fluid pipe 62 is provided with a regulating valve 64 that adjusts the passage amount of the heating fluid S in the heating fluid pipe 62, and the hot water pipe 63 is provided with a temperature sensor 65 in the vicinity of the outlet side of the heat exchanger 60. (For example, refer to Patent Document 1).
JP 2006-127719 A

  According to the hot water supply device, the hot water M is generated by heat exchange between the cold water C from the water supply source WA and the heating fluid S from the heating fluid supply source VA in the heat exchanger 60. It is taken out by opening the valve. The heated fluid S after the heat exchange through the heat exchanger 11 is discharged from the discharge passage 67 to the outside as condensate (drain). In this hot water supply apparatus, the temperature of the hot water M generated by the heat exchanger 60 is detected by the temperature sensor 65, and the temperature information of the detected hot water M is fed back to the control valve 64 by the feedback control circuit 68. If the temperature is high, the supply amount of the heating fluid S to the heat exchanger 60 is decreased by the steam control valve 64 to lower the temperature of the hot water M, and if the temperature of the warm water M is low, the supply amount of the heating fluid S is increased by the control valve 64. Then, the temperature of the hot water M is raised.

  However, in the case of the hot water supply device, even when the curan 66 is closed, that is, when the hot water M is not used, the temperature of the hot water M generated by the heat exchanger 60 is always detected by the temperature sensor 65. The detected temperature information of the hot water M is fed back to the control valve 64 by the feedback control circuit 68 and the heating fluid S is supplied to the heat exchanger 60 so that the temperature of the hot water M is always kept constant. However, when the temperature of the hot water M decreases due to the heat radiation of the hot water pipe 63, the heating fluid S is wasted. In addition, the temperature of the hot water M changes due to a delay in sensing of the temperature sensor 65 or a change in temperature of the hot water M relative to a change in the supply amount of the heating fluid S, and it is difficult to generate the hot water M having a stable temperature.

  Then, this invention aims at providing the heating system which can always produce | generate the hot water of the stable temperature, without heating fluids, such as a vapor | steam being wasted.

In order to achieve the above-described object, a heating system according to the present invention includes a heat exchanger that generates hot water by heat exchange between a heating fluid and cold water, and the heat exchange from the heating fluid supply source. A heating fluid passage leading to the heater, a cooling water passage leading the cold water from the water supply source to the heat exchanger, an orifice provided in the cold water passage, and an upstream side and a downstream side of the orifice provided in the heating fluid passage. And a control valve that adjusts the supply amount of the heating fluid to the heat exchanger according to the differential pressure, and the control valve receives the differential pressure at the lower end of the valve stem that extends in the vertical direction and pivots the valve stem. A drive part that drives in the direction, and a valve body part that opens and closes the heating fluid passage at the upper end of the valve stem, and the drive part is introduced upstream by which cold water upstream of the orifice is introduced. Chamber and downstream where cold water downstream of the orifice is introduced With the introduction chamber, and a diaphragm partitioning the said two inlet chamber. Here, the hot water M includes not only hot water of about 40 to 60 ° C. but also hot water of 60 ° C. or higher.

According to this configuration, when the hot water is not used by closing the currant, the cold water is not flowing in the cold water passage, and there is a difference between the upstream side and the downstream side of the orifice provided in the cold water passage. No pressure is generated. In this case, since the regulating valve that adjusts the supply amount of the heating fluid to the heat exchanger according to the differential pressure between the upstream side and the downstream side of the orifice is closed, the heating fluid is supplied to the heat exchanger by the regulating valve. Since it is not supplied, the heated fluid is not wasted. On the other hand, when hot water is used with the curan open, the cold water flows in the cold water passage toward the heat exchanger, and the difference between the cold water between the upstream side and the downstream side of the orifice provided in the cold water passage. Pressure is generated. Therefore, a control valve that adjusts the supply amount of the heating fluid to the heat exchanger according to the differential pressure of the cold water upstream and downstream of the orifice opens, and the heating fluid is supplied to the heat exchanger by this control valve. The At this time, the opening degree of the control valve is adjusted according to the magnitude of the differential pressure. Thus, the heating fluid is not consumed when hot water is not used, and the heating fluid is consumed only when hot water is used, and the supply amount of the heating fluid is controlled according to this differential pressure. Therefore, the heating fluid is used efficiently. Further, there is no delay in temperature detection, and hot water having a stable temperature can be obtained at all times. Furthermore, since the drive part and the valve body part are provided at both ends of the valve stem, the control valve becomes compact. Further, since cold water is introduced into the lower part of the valve stem, unlike the case where steam is introduced into the lower part of the valve stem, there is no possibility that the heat of the steam rises and the cold water is heated and expanded.

  Preferably, the valve body portion further includes a ball valve which is pressed by the other end portion of the valve stem and moves in the axial direction of the valve stem. Thus, the structure of the valve element is simplified by using the ball valve.

  According to the heating system of the present invention, the heating fluid is not consumed when hot water is not used, and the heating fluid is consumed only when hot water is used. Since it is controlled according to the differential pressure, the heating fluid can be used efficiently. In addition, since the temperature of the hot water is not detected, there is no delay in temperature detection, and hot water having a stable temperature is always obtained.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a system diagram of a heating system according to the present invention. The heating system 10 shown in the figure includes a heat exchanger 11 that generates hot water M by heating cold water C that is a fluid to be heated with heat of a heating fluid S such as steam. As the heat exchanger 11, for example, a plate type heat exchanger in which a plurality of plates are stacked and a passage of a heating fluid (not shown) and a passage of cold water as a fluid to be heated are alternately arranged via the plates. Is preferable because of its small size and large heat exchange capacity.

  The heating system 10 further includes a cold water passage 12 that leads the cold water C supplied from the water supply source WA to the heat exchanger 11 and a heating fluid S such as steam supplied from the heating fluid supply source VA to the heat exchanger 11. The heated fluid passage 13 that leads to the heated fluid passage 13, the warm water passage 14 that leads out the heated water M that is the heated fluid generated in the heat exchanger 11, and the heated fluid S after the heat exchange that has passed through the heat exchanger 11 And a discharge passage 15 for discharging the water as condensate (drain).

  The cold water passage 12 is provided with an orifice 16, and the heating fluid passage 14 is provided with a regulating valve 17 that adjusts the supply amount of the heating fluid S to the heat exchanger 11. As shown in FIG. 2, the orifice 16 is provided with a standing wall 51 extending in a direction perpendicular to the flow direction, for example, in a cold water pipe 50 constituting the cold water passage 12, and a small hole 51 a is provided in the center of the standing wall 51. The flow rate of the cold water C flowing from the upstream side to the downstream side passes through the small hole 51a of the standing wall 51 is reduced. The upstream introduction pipe 52 that forms the upstream introduction path 18 is branched from the vicinity of the upstream side with the standing wall 51 interposed therebetween, and the downstream introduction path that forms the downstream introduction path 19 from the vicinity of the downstream side with the standing wall 51 interposed therebetween. The pipe 53 is branched, and the ends of the upstream introduction pipe 52 and the downstream introduction pipe 53 are connected to the control valve 17 in FIG. The control valve 17 has a structure in which the opening degree can be adjusted by opening the differential pressure between the upstream pressure and the downstream pressure of the orifice 16. When the hot water M is used, the differential pressure is Therefore, the supply amount of the heating fluid S to the heat exchanger 11 in FIG. 1 is adjusted according to the differential pressure.

  A hot water supply passage 23 is connected downstream of the hot water passage 14 to guide the hot water M guided to the hot water passage 14 to a hot water supply valve (curan) 24 serving as a hot water outlet. In addition, although not shown in figure, when the said hot water M is warm water before the said currant 24, you may provide the hot water mixing valve which mixes cold water C with this and produces | generates low temperature warm water.

Next, a specific structure of the control valve 17 will be described with reference to FIG. The figure shows the closed state of the control valve 17. As shown in the figure, the control valve 17 has a valve rod 26 extending in the vertical direction slidably supported in a casing 25 having a heating fluid passage 13 formed in the upper portion. (the lower end), the drive unit 27 to the valve stem 26 receives a differential pressure between the pressure of the pressure and the downstream side of the upstream side of the orifice 16 is driven in the axial direction is provided, the other end of the valve stem 26 (the upper end ) Is provided with a valve body 28 composed of a ball valve for opening and closing the heating fluid passage 13. An O-ring 42 is attached to a sliding surface portion between the valve stem 26 and the casing 25 to ensure airtightness and watertightness so that the cold water C from the downstream introduction chamber 19 does not enter the heating fluid passage 13. Is considered. In the embodiment shown in FIGS. 2 to 3, the valve stem 26 and the valve body portion 28 are separate bodies, but the valve stem 26 and the valve body portion 28 may be integrally formed. .

  The drive unit 27 includes a disk-shaped receiving member 26 a provided at the lower end of the valve rod 26, and a diaphragm 30 fixed to the receiving member 26 a, and the lower side partitioned by the diaphragm 30 An upstream introduction chamber 38 into which the cold water C upstream of the orifice 16 is introduced from the upstream introduction passage 18 is provided, and the cold water C downstream of the orifice 16 from the downstream introduction chamber 19 is provided on the upper side partitioned by the diaphragm 30. A downstream side introduction chamber 39 is provided. The ball valve 28 is pressed toward the upper end of the valve stem 26 and the valve seat 25 a by a spring 29 interposed between the ball valve 28 and the casing 25.

  Next, the operation of the heating system configured as described above will be described. First, when using the hot water M that opens the currant 24 in FIG. 1, the cold water C from the water supply source WA passes through the orifice 16 provided in the cold water passage 12 and enters the heat exchanger 11. When the cold water C passes through the orifice 16, the pressure in the vicinity of the downstream side of the orifice 16 in the cold water passage 12 becomes smaller than the pressure in the vicinity of the upstream side due to the venturi effect. These two pressures act on the upstream side introduction chamber 38 and the downstream side introduction chamber 39 shown in FIG. 4 via the upstream side introduction chamber 18 and the downstream side introduction chamber 19, and the diaphragm 30 is deformed upward to cause the receiving member. 26a is pushed upward, and the valve stem 26 is driven axially upward. As a result, the ball valve 28 moves upward to open the heating fluid passage 13. That is, the valve is opened. Here, since the upstream side introduction chamber 38 and the downstream side introduction chamber 39 that constitute the drive unit 27 are disposed below the heating fluid passage 13, the heat from the heating fluid S passing through the heating fluid passage 13. In response to this, the valve operation is stabilized without being heated and expanded. The adjustment valve 17 adjusts the supply amount of the heating fluid S to the heat exchanger 11 according to the differential pressure between the introduction chambers 38 and 39, and supplies the heating fluid S to the heat exchanger 11 in FIG.

  When the hot water M is not used, since the cold water C does not flow in the cold water passage 12, the differential pressure between the upstream side and the downstream side across the orifice 16 becomes zero. Therefore, the ball valve 28 is pressed against the valve seat 25a by the spring force of the spring 29 in FIG. 3 to close the valve, thereby closing the heating fluid passage 13 and stopping the supply of the heating fluid S to the heat exchanger 11. Thereby, useless consumption of the heating fluid S is suppressed. Moreover, since it does not operate by detecting the temperature of the hot water, there is no delay in temperature detection, and hot water with a stable temperature can always be obtained.

  Next, the relationship between the flow rate and temperature of hot water obtained by the present invention will be described with reference to FIG. In the figure, when the steam pressure is 0.3 MPa (gauge pressure), as shown by the solid line, the temperature of the hot water M increases rapidly as the flow rate of the hot water increases from 2 L / min to 5 L / min, and is close to 90 ° C. Rose to. When the hot water flow rate is 7 L / min, the peak reaches 100 ° C., and when the hot water flow rate is 7 L / min or more, the temperature tends to decrease proportionally. When it is desired to use hot water of 60 ° C. or higher, the flow rate range is about 4 to 27 L / min as shown by the symbol A, and there is a wide usage range. Further, when it is desired to use hot water of 40 ° C. or higher, the flow range is approximately 3 to 35 L / min, as shown by the symbol B, and the use range is extremely wide.

  On the other hand, when the steam pressure is 0.1 MPa (gauge pressure), the temperature of the hot water M increases as the flow rate of the hot water increases from 2 L / min as shown by the alternate long and short dash line, and rises to nearly 80 ° C. of the peak temperature. When the hot water flow rate is 14 L / min or more, the temperature is reduced proportionally. The flow rate range in which hot water can be used is narrower than when the steam pressure is 0.3 MPa.

It is a systematic diagram of the heating system which concerns on this invention. It is a longitudinal cross-sectional view of the vicinity of an orifice. It is a longitudinal cross-sectional view which shows the valve closing state of the control valve used with the heating system. It is a longitudinal cross-sectional view which shows the valve opening state of the control valve used with the same heating system. It is a graph explaining the relationship between the warm water temperature and the warm water flow rate by the differential pressure | voltage change of an upstream side and a downstream side across an orifice, and range use of warm water. It is a systematic diagram of the conventional heating system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Heating system 11 Heat exchanger 12 Chilled water passage 13 Heating fluid passage 14 Hot water passage 15 Discharge passage 16 Orifice 17 Control valve 18 Upstream side introduction chamber 19 Downstream side introduction chamber 25 Casing 26 Valve rod 27 Drive part 38 Upstream side introduction chamber 39 Downstream Side introduction chamber VA Heating fluid supply source WA Water supply source S Heating fluid C Cold water

Claims (2)

A heat exchanger that generates hot water by heat exchange between the heating fluid and cold water;
A heating fluid passage for directing the heating fluid from a heating fluid supply to the heat exchanger;
A cold water passage for guiding cold water from a water supply source to the heat exchanger;
An orifice provided in the cold water passage;
A regulating valve that is provided in the heating fluid passage and adjusts the amount of heating fluid supplied to the heat exchanger according to the differential pressure between the upstream side and the downstream side of the orifice;
With
The control valve has a drive unit that receives the differential pressure and drives the valve rod in the axial direction at a lower end of a valve rod that extends in a vertical direction, and opens and closes the heating fluid passage at the upper end of the valve rod. Has a body,
The drive unit is
An upstream introduction chamber into which cold water upstream of the orifice is introduced;
A downstream introduction chamber into which cold water downstream of the orifice is introduced;
A diaphragm for partitioning the introduction chambers;
Having a heating system. 2. The heating system according to claim 1 , wherein the valve body portion is a ball valve that is pressed by the other end portion of the valve stem and moves in the axial direction of the valve stem.

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