JPH0435645Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a mixing valve for a hot water production device.

[Conventional technology]

In general, factories and the like have boiler equipment for production, cooling and heating, and a considerable number of simple hot water production apparatuses are in use that utilize excess steam generated from the boiler equipment as a heat source. For example, as shown in FIG. 1, this hot water production apparatus consists of a steam introduction pipe 1 connected to a steam source (not shown), a drain discharge pipe 3 having a drain trap 2 in the middle, and a cold water supply pipe connected to a cold water source (not shown). A heat exchanger 6 to which an inlet pipe 4 and a hot water feed pipe 5 for feeding hot water heated by steam are attached, a branch pipe 4a from the cold water inlet pipe 4, and a hot water feed pipe. 5 and a hot water supply pipe 7 connected to a hot water faucet (not shown). detects it instantaneously and converts it into mechanical movement of the valve body,
Thereby, heat and cold water are mixed in an appropriate ratio based on the valve body whose position is set in advance by the adjustment lever 57, and hot water at a constant temperature is produced. In addition, pressure gauges 9 are installed in the cold water introduction pipe 4 and the hot water supply pipe 5 to measure the cold water pressure P _W and the hot water outlet pressure P _H, respectively.
is installed.

As shown in FIGS. 2A and 2B, for example, a conventional mixing valve of this type includes a valve box 41, a guide 42 screwed onto the valve box 41, and a shaft portion attached to the guide 42.
The valve body 4 is supported via a ring 43.
1, a frame 45 fixed to the top of the valve box 41, a diaphragm chamber main body 46 fixed to the top of the frame 45, and a diaphragm chamber main body 46. A diaphragm chamber lid 48 is fixed onto the main body 46 so as to sandwich the peripheral edge of the diaphragm 47 between the diaphragm 4
The diaphragm receiver 49 is arranged to receive the operating pressure of 7, and the upper end is screwed to the diaphragm receiver 49, and the vicinity of the upper end is vertically slidably supported by the diaphragm chamber main body 46 via an O-ring 50, and the lower end is hanging down. Tightened diaphragm receiving rod 51
, a lower spring receiver 52 fixed to the middle part of the frame 45 and slidably supporting the vicinity of the lower end of the diaphragm receiver bar 51, an upper spring receiver 53 screwed to the middle part of the diaphragm receiver bar, and both springs. Receivers 52 and 53
a spring 54 interposed between the two, a joint 56 whose upper end is screwed onto the lower end of the diaphragm receiving rod 51, whose lower end is fitted onto the upper end of the shaft of the valve body 44, and which is fixed by a lock bolt 55; An adjustment lever 57 fixed perpendicularly to the shaft of the valve body 44, a support spring 58 to prevent the shaft of the valve body 44 from falling out of the joint 56 when the lock bolt 55 is loosened during adjustment, and a lift are adjusted. It consisted of a lock nut 59 for fixing the water, a conduit 60 for guiding the hot water outlet pressure to the lower chamber of the diaphragm, and a conduit 61 for guiding the cold water inlet pressure to the upper chamber of the diaphragm.

[Problem that the invention attempts to solve]

However, the above mixing valve has a diaphragm receiving rod 5.
1 and the sliding shaft portion of the valve body 44 with an O-ring 5.
Because it was designed to be sealed with 0,43 etc.
There was a problem in that the O-rings 50, 43 were worn out in a short period of time due to the sliding movement of these shaft parts, and as a result, hot water was likely to leak to the outside. Therefore, it is necessary to replace the O-rings 50 and 43 in a short period of time, but in that case, the entire mixing valve must be removed from the piping, and the valve body 44 and diaphragm receiving rod 51 must be removed from the mixing valve body, so disassembly and assembly is required. is troublesome,
Furthermore, since the diaphragm receiving rod 51 and the shaft portion of the valve body 44 are connected by a joint 56, it is also necessary to adjust the valve lift, which poses a problem in that these operations require skill and maintenance costs are high. In addition, there is considerable sliding resistance in the O-rings 50, 43, etc. that seal the sliding shaft, and the valve body 4 resists this resistance.
In order to operate the diaphragm 47 smoothly, the operating pressure of the diaphragm 47, that is, the differential pressure between hot water and cold water, must be set to a large value, and even then, large hysteresis occurs due to the resistance of the O-rings 50 and 43 (see Fig. 8). ), there was a problem in that the movement of the valve body 44 lacked smoothness, resulting in variations in hot water temperature. In addition, a long conduit 60 with hot water outlet pressure
Since the hot water was configured to be guided to the lower chamber of the diaphragm via the There was a problem with hot water not coming out right away. Further, since a joint 56 is required to connect the diaphragm receiving rod 51 and the shaft of the valve body 44, the number of parts increases, which increases manufacturing costs, and the height of the entire mixing valve increases, making it large. There was a problem that it turned into

〔the purpose〕

In view of the above problems, the present invention provides a mixing valve that is less likely to leak hot water to the outside, has low maintenance costs, eliminates variations in hot water temperature, has low manufacturing costs, and can be miniaturized.

[Means and actions for solving problems]

The mixing valve according to the present invention includes: a valve box having a cylinder chamber, a hot water inlet, a cold water inlet, and a hot water outlet communicating with the cylinder chamber; a diaphragm chamber main body fixed on the valve box via an O-ring; A diaphragm chamber lid that is fixed to the diaphragm chamber body and forms a diaphragm chamber with the main body, and a diaphragm chamber lid that is slidably inserted into the cylinder chamber and communicates with an opening that can overlap the hot water inlet and the cold water inlet, respectively, and the hot water outlet. A valve body is provided with a hollow portion in the shaft portion that communicates with the lower chamber of the cylinder chamber and the diaphragm chamber, and has a two-chamfered portion formed at the top, and a valve body that fits into the two-chamfered portion and rotates within the guide ring. a movable adjustment plug, a diaphragm receiver fixed to the shaft of the valve body via an O-ring, an inner edge fixed to the diaphragm receiver and an outer edge connected to the diaphragm chamber body and the diaphragm chamber lid. The O-ring does not move relative to the other because it is composed of a diaphragm that is sandwiched between the diaphragm and divides the diaphragm chamber into two upper and lower chambers, and a cold water pressure introduction pipe that communicates the cold water inlet of the valve box with the upper chamber of the diaphragm. It is arranged only between contact surfaces or between contact surfaces that rotate relative to each other only during adjustment, and is not attached to the sliding shaft at all, and the shaft of the valve body is directly connected to the diaphragm, eliminating the need for adjusting the valve lift. The number of parts is reduced and the overall height of the mixing valve is lowered, and a hollow part is provided in the valve body to communicate the hot water outlet and the diaphragm chamber, so that changes in the hot water outlet pressure are transmitted to the diaphragm chamber without delay. Each component has a concentric structure and is assembled sequentially from one direction, thereby eliminating the need to remove the entire mixing valve from the piping when replacing the O-ring.

〔Example〕

Hereinafter, the present invention will be described in detail based on an embodiment shown in FIGS. 3 to 6. Reference numeral 11 indicates a cylinder chamber 11a penetrating vertically;
A hot water inlet 11b (FIG. 4A) that is open on the inner circumferential wall of the pipe a and is connected to the hot water supply pipe 5, and a cold water inlet 11c that is connected to the branch pipe 4a from the cold water introduction pipe 4.
(FIG. 4B) and a hot water outlet 11d provided at the bottom and connected to the hot water supply pipe 7,
12 is fixed to the top surface of the valve box 11 by bolts 13, is provided at the bottom, and is connected to the cylinder chamber 11a.
14 is a diaphragm chamber body having a center hole 12a that communicates with the center hole 12a, a stopper member 12b provided on the inner wall of the intermediate portion, and an air vent hole 12c provided on the top peripheral wall; O-ring interposed between
Reference numeral 15 indicates a guide ring fitted into the center hole 12a, and reference numeral 16 indicates a piston portion 16a fitted into the cylinder chamber 11a so as to be able to move up and down, and the guide ring 1.
The piston part 1 is formed hollow from the piston part 16a to the intermediate position of the shaft part 16b.
The openings 16c (FIG. 4A) and 16d (FIG. 4B) that open in the peripheral wall of the piston 6a, the opening 16e that opens in the bottom of the piston portion 16a, and the shaft portion 16b are provided in the peripheral wall at an intermediate position, and are located inside the shaft portion 16b. A communication hole 16f communicating with the inside of the diaphragm chamber main body 12 and the shaft portion 16
A two-chamfered portion 16g formed at the top of b (Fig. 5)
17 and 18 are stainless steel rings interposed between the inner circumferential surface of the cylinder chamber 11a and the outer circumferential surface of the piston portion 16a, and 19 is fitted into the shaft portion 16b. The lower end 1 is tightened by the action of the double nut 20 screwed onto the
9a (FIG. 6) and the stepped portion 16b' (sixth step) of the shaft portion 16b.
A diaphragm receiver 21 is made rotatable and prevented from coming off upwards by leaving a slight gap δ (see FIG. 6) between the outer peripheral surface of the shaft portion 16b and the diaphragm receiver 19. The O-ring 22 is a spring whose elasticity is set to balance the vertical pressure difference ΔP acting on the diaphragm, which will be described later, by imparting an upward movement habit to the diaphragm receiver 19. , 23 is a diaphragm retainer fitted into the cylindrical portion 19b at the upper end of the diaphragm receiver 19, 24 is a tightening plate screwed onto the cylindrical portion 19b, and 25 is screwed onto the tightening plate 24 so that when tightened, A bolt acts to press the diaphragm retainer 23 to the diaphragm receiver 19, 26 is a diaphragm chamber lid fixed to the diaphragm chamber main body 12 by a bolt 27 and has a center hole 26a provided at the top, and 28 is an inner edge. The diaphragm chamber is sandwiched between the diaphragm receiver 19 and the diaphragm retainer 23, and the outer edge portion is sandwiched between the outer edges of the diaphragm chamber main body 12 and the diaphragm chamber lid 26, thereby dividing the diaphragm chamber into an upper chamber 29 and a lower chamber 30. A divided diaphragm, 31 is a guide ring fitted into the center hole 26a, and 32 is a slotted portion 32a, a shaft portion 32b, and a flange portion 32c.
and a two-chamfered portion 32d, and the slotted portion 32a fits into the two-chamfered portion 16g (Fig. 5).
In this way, the shaft portion 32b is rotatably inserted into the guide ring 31, and the flange portion 32c is brought into close contact with the top end surface of the diaphragm chamber cover 26 via the gasket 33. Inner peripheral surface and shaft portion 32 of adjustment plug 32
an O-ring interposed between the outer peripheral surface of b;
Numeral 35 is a lock nut which is screwed onto the top of the diaphragm chamber lid 26 and acts to press the flange portion 32c of the adjustment plug 32 onto the top end surface of the diaphragm chamber lid 26 via the gasket 33 when tightened; and 36 is an adjustment nut. An indicator arrow is fixed to the top surface of the plug 32, 37 is an arrow name plate fixed to a predetermined position on the outer peripheral surface of the top of the diaphragm chamber lid 26 and indicates the adjustment direction of the set temperature, and 38 is a screw screwed to the top side wall of the diaphragm chamber lid 26. A pipe joint 39 is connected to the cold water inlet 11 and is configured to vent air from the upper chamber 29 by loosening it during initial operation.
A cold water pressure introduction pipe 40 connected between the vicinity of c and the pipe joint 38 is screwed onto the outlet of the air vent hole 12c, and is configured to bleed air from the lower chamber 30 by loosening it during initial operation. This is the air vent valve body. It is assumed that the stopper 12b is provided at a position where the lower end of the piston portion 16a of the valve body 16 can come into contact with the diaphragm receiver 19 before reaching the bottom surface of the cylinder chamber 11a of the valve box 11.

Since the mixing valve according to the present invention is configured as described above, during normal operation, hot water flows in from the overlapping part of the hot water inlet 11b and the opening 16c (the shaded part in FIG. 4A), and the cold water inlet 11c and the opening 1
6d (shaded area in FIG. 4B) mixes in the piston portion 16a to become hot water, and the hot water passes through the opening 16e and the hot water outlet 11d to the hot water supply pipe 7 (the Figure 1). The temperature of the hot water at this time changes depending on the ratio of the amount of hot water and the amount of cold water flowing within a certain period of time, assuming that the respective temperatures of the hot water and the cold water are constant.
Also, at this time, the cold water inlet pressure P _W of the cold water introduction pipe 4 is transferred to the upper chamber 29 through the cold water pressure introduction pipe 39 and the pipe joint 38.
The hot water outlet pressure P _H of the hot water supply pipe 7 is guided into the lower chamber 30 through the valve body 16 and the communication hole 16f, so the diaphragm 28 has a differential pressure ΔP (=
P _W −P _H ) acts. Note that the cold water in the cold water introduction pipe 4 uses water at a substantially constant pressure from a water supply pump or an elevated water tank (not shown) as a cold water source, so the cold water inlet pressure P _W is generally maintained at a substantially constant pressure.

Now, in this state, the hot water flow rate W is changed by opening and closing the hot water tap (not shown). For example, the flow rate W
If P increases (or decreases), this will directly appear as a decrease (increase) in the hot water outlet pressure P _H.
Then, the pressure in the lower chamber 30 decreases (increases) and the differential pressure ΔP changes, causing the diaphragm 28 to displace downward (upward) (valve lift changes), which causes the valve body 16 to descend (rise). ), the area of the overlapping portion of the hot water inlet 11b and the opening 16c (the shaded area in FIG. 4A), the area of the cold water inlet 11c and the opening 1
The area of the overlapping portion 6d (the shaded portion in FIG. 4B) increases (or decreases) at the same ratio.

Therefore, when the hot water flow rate W changes, both the amount W _A of hot water and the amount W _B of cold water flowing into the piston portion 16a of the valve body 16 within a certain period of time change, but the ratio of the two is W _A /W. Since _B does not change (see Figure 7), the temperature of the hot water remains constant.

Also, if you want to change the set temperature of hot water, you can do the following operation. That is, only when changing the set temperature, the lock nut 35 is temporarily loosened, and then the adjustment plug is turned in the desired direction while checking the overlapping position of the indicator arrow 36 and the arrow name plate 37. Then, since the slotted portion 32a of the adjustment plug 32 and the two-chamfered portion 16g of the valve body 16 are fitted, the valve body 16 also rotates in the same direction while the valve lift changes slightly from to '. Therefore, the respective areas of the overlapping part of the hot water inlet 11b and the opening 16c and the overlapping part of the cold water inlet 11c and the opening 16d change from those shown in FIG. 4 A and B to those shown in FIG. 4 C and D, for example. .

Therefore, the ratio of the amount of hot water and the amount of cold water flowing in within a certain period of time changes from W _A /W _B to W _A ′/W _B ′ (see Figure 7), so the set temperature of hot water changes. .
Finally, by tightening the lock nut 35, the adjustment plug 32 is fixed, and as a result, the rotational position of the valve body 16 is also fixed, and the subsequent movement of the valve body 16 is only up and down, and the subsequent hot water temperature becomes constant at the reset temperature. Furthermore, when the hot water flow rate is large, the hot water outlet pressure P _H drops significantly and the difference between it and the cold water inlet pressure P _W becomes large, so the valve body 16 drops significantly due to the above principle, but in the case of this mixing valve, the valve body 16 Since the diaphragm receiver 19 is configured to be received by the stopper 12b before the lower end of the piston portion 16a of the body 16 reaches the bottom surface of the cylinder chamber 11a of the valve box 11, the piston portion 16a is configured to be received by the stopper 12b.
There is no possibility that the lower end of a is brought into pressure contact with the bottom surface of the cylinder chamber 11a. Therefore, the set temperature can be adjusted even when the hot water flow rate is large.

Note that if the cold water inlet pressure P _W temporarily increases (or decreases) during use while the hot water flow rate W from the hot water tap (not shown) is constant, the pressure in the upper chamber 29 is increased by the cold water pressure introduction pipe 39. As a result of the rise (decrease) and the change in the differential pressure ΔP, the valve body 16 begins to move slightly in an attempt to descend (rise), and the amount of hot water W _A and the amount of cold water W _B will increase (decrease) while keeping the ratio constant. shall be. However, if the amount of hot water flowing out from the mixing valve to the hot water supply pipe 7 increases slightly, the hot water outlet pressure P _H will increase because the hot water flow rate W from the hot water tap is constant.
As a result, the valve body 16 now rises (descends) and returns to the position where the amount of outflow to the hot water supply pipe 7 is equal to the amount of hot water outflow W from the hot water tap. This position is a position before the cold water inlet pressure P _W temporarily increases (decreases), and the valve body 16 moves up and down while the differential pressure ΔP of the diaphragm and the elasticity of the spring 22 are balanced.

Therefore, the relationship shown in Figure 8 is established between the hot water flow rate W and the differential pressure ΔP, and the cold water inlet pressure
Even if _PW changes, the valve lift can be immediately corrected to keep the hot water temperature constant.

In this regard, in conventional mixing valves, when the cold water inlet pressure _PW changes temporarily, a response delay occurs and hysteresis is large, so the flow rate from the mixing valve to the hot water supply pipe 7 fluctuates, resulting in The flow rate of hot water from the hot water tap was fluctuating.

Although the hot water temperature was assumed to be constant in the above explanation, the hot water temperature has a certain relationship with the flow rate (heat exchange characteristics)
In the case where the ratio of the area of the overlapping part of the hot water inlet 11b and the opening 16c to the area of the overlapping part of the cold water inlet 11c and the opening 16d is changed according to the heat exchange characteristics as shown in FIGS. 4A and B, By changing it with the lift, it is possible to mix the appropriate ratio and create hot water at a constant temperature.

The operating principle of the mixing valve according to the present invention and the method of adjusting the set temperature of hot water have been explained above.As is clear from the above structure, this mixing valve is capable of adjusting the set temperature between the contact surfaces where the O-rings do not move at all relative to each other. Since the O-ring is only interposed between the contact surfaces that rotate relative to each other for a very short period of time, and is not attached to the sliding shaft, the O-ring hardly wears out, and as a result, there is no leakage of hot water to the outside. Hard to occur.
Furthermore, there is no need to replace the O-ring in a short period of time.
In addition, since each component has a concentric structure and is assembled sequentially from one direction, each component can be replaced by loosening the corresponding nuts and bolts when replacing each O-ring. Since the mixing valve can be separated in the same direction (upward in FIG. 3), there is no need to remove the entire mixing valve from the piping, which facilitates disassembly and assembly.
Since the valve is directly connected to the diaphragm receiver 19, there is no need to adjust the valve lift, and therefore, these operations do not require skill and maintenance costs are reduced. In addition, since there is no O-ring on the sliding shaft, the sliding resistance is small, and almost no hysteresis occurs in the movement of the valve body 16. As a result, the operation of the diaphragm 28, that is, the differential pressure between hot and cold water, can be set to a small value. As the valve body moves more smoothly,
It is possible to eliminate variations in hot water temperature. or,
Since the hot water outlet pressure is guided to the diaphragm chamber through the inside of the valve body 16, changes in the hot water flow rate, that is, changes in the hot water outlet pressure, are transmitted to the diaphragm chamber without delay, and as a result, the hot water tap, etc. is opened. The hot water flows out smoothly. In addition, since the shaft portion 16b of the valve body 16 is directly connected to the diaphragm receiver 19, the number of parts is significantly reduced compared to conventional mixing valves, reducing manufacturing costs and reducing the overall height of the mixing valve. It can be made smaller.

[Effect of idea]

As mentioned above, the mixing valve of the hot water production device according to the present invention has the following practical advantages: it is difficult to leak hot water to the outside, it has low maintenance costs, it eliminates variations in hot water temperature, it has low manufacturing costs, and it can be made compact. It has advantages.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a hot water production device, Fig. 2 A and B are a cross-sectional view and a side view of a conventional mixing valve, respectively, and Fig. 3 is a schematic diagram of a hot water production device.
The figure is a longitudinal cross-sectional view of one embodiment of the mixing valve according to the present invention (Figure 4 A and B are views in the direction of arrows A and B in Figure 3 before changing the set temperature, respectively, C and D are views after changing the set temperature, respectively) Similar arrow view later, No. 5
The figure is a cross-sectional view taken along the line V-V in Figure 3, Figure 6 is an enlarged cross-sectional view of the main part showing the attachment structure of the diaphragm receiver to the shaft of the valve body, and Figure 7 is a hot water flow rate of the mixing valve according to the present invention. FIG. 8 is a diagram showing the relationship between the vertical differential pressure of the diaphragm and the hot water flow rate for the present invention and the conventional example. 11...Valve box, 12...Diaphragm chamber body,
13... Bolt, 14... O ring, 15... Guide ring, 16... Valve body, 17, 18... Stainless steel ring, 19... Diaphragm receiver, 20
...Double nut, 21...O ring, 22...
Spring, 23...Diaphragm holder, 24...
... Tightening plate, 25 ... Bolt, 26 ... Diaphragm chamber cover, 27 ... Bolt, 28 ... Diaphragm, 29 ... Upper chamber, 30 ... Lower chamber, 31 ... Guide ring, 32 ... Adjustment plug , 33... Gasket, 34... O-ring, 35... Lock nut, 36... Indication arrow, 37... Arrow nameplate, 38...
... Pipe joint, 39 ... Cold water pressure introduction pipe, 40 ... Air vent valve body.

Claims (1)

[Claim for Utility Model Registration] A diaphragm instantly detects the pressure change on the hot water outlet side caused by a change in hot water flow rate and converts it into mechanical movement of the valve body, thereby adjusting the hot water and cold water at an appropriate ratio. A mixing valve for a hot water production device that mixes water at a constant temperature to produce hot water at a constant temperature, the valve box having a cylinder chamber, a hot water inlet, a cold water inlet, and a hot water outlet communicating with the cylinder chamber;
A diaphragm chamber main body fixed on the valve box via an O-ring, a diaphragm chamber cover fixed to the diaphragm chamber main body and forming a diaphragm chamber with the main body, and an outer edge portion of the diaphragm chamber main body and the diaphragm chamber cover. a diaphragm sandwiched between the diaphragm chamber and the diaphragm chamber to partition the diaphragm chamber into an upper chamber and a lower chamber; An opening that can overlap with the inlet, an opening formed in the bottom of the piston part and communicating with the hot water outlet, and a hollow part formed in the shaft part that communicates the cylinder chamber and the lower chamber, and a two-chamfered part is formed in the top part. an adjustment plug that is fitted into the two-chamfered portion and can rotate the valve element within the guide ring; a lock nut that fixes the adjustment plug at an arbitrary position; A diaphragm receiver having a fixed peripheral portion and fixed to the shaft portion of the valve body via an O-ring, and a cold water pressure introduction pipe communicating the cold water inlet of the valve box and the upper chamber of the diaphragm chamber. Characteristic mixing valve.