JPH11201446A - Water pressure response gas valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a flow control valve disk restricting operation, by keeping a flow control valve disk free by a correction spring until approaching at specified distance from a full-open position to a flow control valve hole, and pressing the valve disk in a direction away from the flow control valve hole after approaching at specified distance. SOLUTION: While in an initial state i.e. a water flow stop state in a water circuit 81, a flow control valve disk 51 is in the most remote state from the full-open position of a flow control valve hole 53 and a specified gap b is formed between a peripheral flange 515 at the upstream end of the flow control valve disk 51 and upstream end of a correction spring 83 to hold the correction spring 83 free. After approaching at specified distance from the full-open position of the flow control valve disk 51 to the flow control valve hole 53, the flow control valve disk 51 is pressed by the correction spring 83 in a direction away from the flow control valve hole 53, thereby suppressing the flow control valve disk 51 from restricting operation and flow rate from excessive reduction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water pressure responsive gas valve incorporated in an instantaneous water heater or the like, and it is possible to reduce a decrease in the amount of hot water even when a water supply pressure on a water supply pipe connected to the water heater increases. It is something that can be suppressed.

[0002]

2. Description of the Related Art FIG. 4 is a schematic view of an instantaneous water heater incorporating a conventional hydraulically responsive gas valve. The gas circuit (11) is provided with an electromagnetic valve (13) and a downstream responsive valve (15), and a nozzle (16) (16) at the downstream end of the gas circuit (11). Faces the gas inlets (22) and (22) of the gas burners (21) and (21).

On the other hand, a water governor (31) for detecting a water flow is provided at an upstream end of the water circuit (26) passing through the heat exchanger (24) so as to open a gas circuit. The water governor (31) has a function of alleviating a change in the amount of hot water due to a change in the water supply pressure. Further, a shower head (28) is provided at a downstream end of the water circuit (26). Further, the water governor (31) is adapted to be linked with the operation button (35) via the valve opening lever (33), and the operation signal of the operation button (35) is
It is applied to a control circuit (37) for controlling the solenoid valve (13) and the like.

The water governor (31) has a valve casing (39).
Is provided with an on-off valve (459) interlocking with the valve-opening lever (33), such that the on-off valve (459) opens and closes the valve port (49) at the upstream end of the water passage cylinder (47). Has become. The water flow control valve (47) has a flow control valve body that is movable in the axial direction.
(51) is accommodated, and a flow control valve opening (53) is opposed to the flow control valve (51) from the downstream side, and the flow control valve ( The valve opening is adjusted by the contact / separation operation of 51).

A primary pressure chamber downstream of the flow control valve port (53).
(55) is partitioned by a diaphragm (59) from a secondary pressure chamber (57), and the secondary pressure chamber (57) is a throttle (61) formed downstream of the primary pressure chamber (55). ) Is connected to the downstream side through a communication passage (62). The spring receiving disk (60) at the tip of the valve shaft (63) protruding from the flow rate adjusting valve body (51) is a mounting spring (86).
At the diaphragm (59) side,
The flow regulating valve element (51) moves following the diaphragm (59). Further, a rod (6) which comes into contact with the diaphragm (59) from the opposite side of the flow regulating valve body (51).
The other end of (4) is provided with a switch closing piece (65) which is urged by a return spring (71) and turns ON / OFF the limit switch (67). 6
A lift valve type reaction valve (15) urged in the valve closing direction by a valve closing spring (69) with a predetermined clearance (usually about 2.5 mm) and a rod (65a) integral with 5) Is provided.

In this apparatus, when the operation button (35) is pushed in, the on-off valve (459) is opened in conjunction with the valve opening lever (33) rotated by the tip (36) of the operation button (35). Operate.
That is, the on-off valve (459) moves in the direction away from the valve port (49) at the upstream end of the water flow pipe (47) to the upstream side, and as a result, the valve port (4
9) is opened. Then, the water inlet of the water governor (31) (7
3) → Valve (49) of water flow cylinder (47) → Flow control valve port (53) at downstream end of water flow cylinder (47) → Primary pressure chamber (55) of water governor (31) → Throttle section
Water is supplied through the route of (61) → heat exchanger (24) → shower head (28). At this time, the flow rate is reduced by the throttle section (61), and a constant pressure drop occurs in this section. Then, the pressure of the secondary pressure chamber (57) communicating with the downstream side of the throttle portion (61) decreases, whereby the diaphragm (59) deforms toward the secondary pressure chamber (57) and the response valve ( 15) opens the valve against the urging force of the valve closing spring (69).

When the response valve (15) is opened, the response valve (1) is opened.
The arm (68) of the limit switch (67) pressed by the switch-on piece (65) interlocked with 5) becomes non-pressed and turns ON, and the solenoid valve (13) is output by the output of the control circuit (37). ) Is kept open to supply gas to the gas burners (21) and (21), and the gas burners (21) and (21) burn due to sparks from the ignition electrode (75). Thereby, the heat exchanger (24) is heated and the hot water flows out of the shower head (28).

In the above tapping state, when the supply pressure of the water supply pipe connected to the water inlet (73) of the water governor (31) fluctuates, the pressure difference between the primary pressure chamber (55) and the secondary pressure chamber (57) changes. At this time, the flow regulating valve body (51) moves toward and away from the flow regulating valve port (53), whereby the throttle amount changes and the pressure difference is kept constant, and the water circuit (26) The flow rate in parentheses) is kept constant.
That is, when the supply water pressure increases and the flow rate in the water circuit (26) is about to increase, the pressure difference between the primary pressure chamber (55) and the secondary pressure chamber (57) increases, and the flow rate regulating valve element (51) While the throttle operation suppresses the increase in the flow rate, conversely, when the water supply pressure decreases and the flow rate tends to decrease, the pressure difference decreases and the flow adjustment valve body (51) opens. Thus, the decrease in the flow rate is suppressed, and the flow rate through the flow rate adjustment valve port (53) is kept constant.

As described above, in the above-described conventional apparatus, a change in the flow rate in the water circuit (26) due to a change in the supply water pressure on the water supply pipe upstream of the water governor (31) can be suppressed to some extent. Even if the water pressure fluctuates, the fluctuation in the amount of hot water from the shower head (28) can be kept small, and a stable hot water operation can be ensured.

[0010]

However, in the above-mentioned conventional apparatus, the amount of hot water can be stabilized to some extent even if the supply water pressure on the upstream side of the water governor (31) fluctuates, but the stability is still unsatisfactory. In particular, when the above-mentioned water supply pressure rises remarkably, the water supply pressure acts on the flow regulating valve body (51) itself, and the diaphragm (59) is excessively deformed toward the secondary pressure chamber (57). Let it. As a result, there has been a problem that the flow regulating valve element (51) is excessively throttled and the flow rate of the water circuit (26) is significantly reduced.

In order to solve the above problem, the flow regulating valve element (51) on which the feed water pressure acts is made small (small pressure receiving area), and the valve closing spring (69) of the response valve (15) is used. It is conceivable that the spring constant is increased, but in the former case, the flow control valve port (53) corresponding to the flow control valve element (51) also becomes small, and the flow path resistance increases. On the other hand, in the latter case, especially when the water supply pressure is low, the response valve (15) becomes difficult to open during the tapping operation, and the operation of igniting the gas burner (21) does not start smoothly.

[0012] The present invention has been made in view of the above points, and it is possible to more reliably prevent a decrease in the amount of hot water when the supply water pressure rises, while ensuring the smoothness of the ignition operation of the gas burner (21) at the time of the hot water operation. It is an object of the present invention to provide a hydraulically responsive gas valve which can be suppressed to a minimum.

[0013]

The technical means according to the first aspect of the present invention adopted to solve the above-mentioned problem is a gas burner.
And a response valve (15) disposed in the gas circuit (11) to (21) and opening and closing in conjunction with the deformation operation of the diaphragm (59) disposed in the water circuit. The diaphragm (59) is stretched so that a pressure receiving surface thereof is exposed in the water circuit, and has a flow rate adjustment valve port formed in a portion of the water circuit opposite to the pressure receiving surface. A flow control valve that faces the flow control valve port from the side opposite to the diaphragm (59) and moves in the direction of coming into contact with and separating from the flow control valve port following the deformation operation of the diaphragm (59). Body (5
1), the flow regulating valve body (51) is kept in a free state from the fully opened position to approach the flow regulating valve port a predetermined distance, and after approaching the predetermined distance, the flow regulating valve body (51) is moved. And a correction spring that urges in a direction away from the flow control valve opening. "

According to the above technical means, when a water flow is generated in the water circuit, a pressure difference between the pressure receiving surface of the diaphragm (59) and the pressure acting on the opposite surface is generated, and the diaphragm (59) adjusts the flow rate opposed thereto. Deformation operation is performed in the direction away from the valve port, and the response valve (15) is opened and the gas circuit (1
Gas flows in 1). When a water flow is generated in the water circuit and the diaphragm (59) deforms, the flow regulating valve body (51)
Since the correction spring is kept in a free state and does not exert an urging force until it approaches the flow control valve port by a predetermined distance, the gas circuit can be operated even when the water supply pressure is low as in the case of the above-described conventional type having no correction spring. The response valve (15) of (11) opens smoothly.

In this state, when the water supply pressure on the upstream water supply pipe side rises, the water supply pressure acts on the pressure receiving surface of the flow control valve body (51), and the flow control valve body (51) is connected to the flow control valve port. Start approaching. However, after the flow regulating valve body (51) approaches the flow regulating valve opening by a predetermined distance (after the response valve (15) is opened), the correction spring is in a non-free state and is compressed. The movement of the flow regulating valve body (51) in the valve closing direction is suppressed by the biasing force of the correction spring, whereby the throttle operation of the flow regulating valve body (51) is suppressed, and an excessive decrease in the flow rate is suppressed. .

Specifically, the correction spring is provided between the flow regulating valve body (51) and a fixed portion formed downstream of the flow regulating valve body (51). Mounted coil spring ”. According to the third aspect of the present invention, "when the pressure receiving area of the flow regulating valve element (51) is 64 mm ² , the spring constant of the correction spring is set to 0.64 kg / mm or more". it can.

Further, the predetermined distance is defined as "the position of the flow regulating valve body (51) when the response valve (15) is opened and the flow regulating valve body (5
The distance between the two points with the fully open position in 1) is not less than that ”(the invention of claim 4). In this case, the correction spring is kept free until the response valve (15) is opened. Therefore, until the response valve (15) opens, the flow regulating valve
(51) is not pushed to the fully open position side by the correction spring, and the smooth opening operation of the response valve (15) can be ensured.

[0018]

As described above, according to the first to fourth aspects of the present invention, the response valve (1) provided in the gas circuit (11) is provided.
Since the compensating spring does not exert biasing force until 5) opens,
A responsive valve similar to the above-mentioned conventional valve not having the correction spring
(15) opens smoothly. When the hydraulic pressure-responsive gas valve of the present invention is incorporated in, for example, a water heater, the response valve (1
Since the ignition operation to the gas burner is normally performed when the valve is opened in 5), in such a case, the ignition operation to the gas burner supplied with gas from the corresponding valve (15) is performed even when the feed water pressure is low. It is performed smoothly. Also, after the flow regulating valve body (51) has approached the flow regulating valve port for a predetermined distance (after the response valve (15) has been opened).
Since the correction spring exerts a biasing force in the direction of suppressing the opening degree throttle operation of the flow regulating valve element (51), the water supply pressure on the upstream water pipe side with the response valve (15) opened. Even if the pressure rises, it becomes difficult for the flow regulating valve body (51) to move in the direction of opening reduction. Therefore, a decrease in the flow rate in the water circuit can be more reliably suppressed as compared with the above-described conventional one having no correction spring.

According to the third aspect of the present invention, when the pressure receiving area of the flow regulating valve element (51) is set to 64 mm ² , the spring constant of the correction spring is set to 0.64 kg / mm or more. It was confirmed that the flow rate of the water circuit could be kept almost constant regardless of the amount. According to the invention of claim 4, the response valve (15)
The correction spring is not compressed unless the flow regulating valve body (51) moves from the fully open position to the position of the flow regulating valve body (51) when the valve is opened. Therefore, the inconvenience that the correction spring is compressed before the response valve (15) is opened can be reliably prevented, and the smooth opening operation of the response valve (15) can be further ensured. it can.

[0020]

Next, an embodiment of the present invention will be described. FIG. 1 is a schematic structural view of an instantaneous water heater in which a hydraulically responsive gas valve according to the present invention is incorporated. The gas circuit (11) is provided with an electromagnetic valve (13) and a downstream valve (15) in the same manner as the conventional one, and a nozzle portion at the downstream end of the gas circuit (11). (16) (16) gas burner (21)
The gas inlets (22) and (22) of (21) are facing. Further, the responsive valve (15) is urged in the valve closing direction by a valve closing spring (69), and a rod (64) extending from the responsive valve (15) to a portion where a water governor (31) described later is provided. A switch closing piece (65) biased by a return spring (71) is provided in the middle of ().

Next, a water governor (31) is provided at the upstream end of the water circuit (26) passing through the heat exchanger (24). The water governor (31), the above-described response valve (15), and the rod (64) connecting these components constitute a hydraulic pressure-responsive gas valve according to the present invention. Next, the structure of the water governor (31) will be described. [Overall Configuration of Water Governor (31)] As shown in FIG. 2, the water casing (39) of the water governor (31) has a water inlet (73) → an arrangement part of the diaphragm valve (45) → a water passage cylinder ( 47) → the water bottle (47)
Downstream of the flow control valve port (53) → the primary pressure chamber (55) between the flow control valve port (53) and the diaphragm (59) → hot water flow control valve (77)
A water circuit (81) connected to the throttle (61) → the water outlet (79) is formed, and the throttle (61) and the secondary pressure chamber (57) adjacent to the diaphragm (59) communicate with the communication passage (62). ).

The details of each component of the water governor (31) will be described below. [About diaphragm valve (45)] Valve casing (39)
An opening (42) formed so as to be connected to the water circuit (81) inside the side wall of the diaphragm (43) is closed by a diaphragm (43) constituting a diaphragm valve (45), and the outer periphery of the diaphragm (43) Of the diaphragm cover (74) covering the opening (42) and a flange (76) on the opening end side of the diaphragm cover (74) and a component wall of the valve casing (39). .

A seat member (40) is locked to the diaphragm (43), and a central protruding shaft (400) is connected to a valve port (41) of a water flow cylinder (47).
3) slidably penetrates through to ensure concentricity between the diaphragm valve (45) and the water pipe (47).
A pilot valve (41) for opening and closing a pilot hole (46) formed through the center of the protruding shaft (400) is urged in a valve closing direction by a spring (48).

The valve shaft (411) of the pilot valve (41) is
Shaft guide (412) mounted on diaphragm cover (74)
And projecting outside the diaphragm cover (74), and near the outer periphery of the overlapping portion of the sheet member (40) and the diaphragm (43), the inside of the diaphragm cover (74) and the valve casing (39). A leak hole (431) is formed to communicate with the inside of the water circuit (81) on the water inlet (73) side.

The downstream end of the above-described water passage cylinder (47) having a valve port (413) opened and closed by the seat member (40) attached to the diaphragm (43) is connected to a valve casing (39). An O-ring (471) is used to press-fit the formed cylindrical recess (470) in a watertight manner. [Regarding Flow Adjusting Valve (51)] The flow adjusting valve (51) housed in the water flow cylinder (47) is arranged at a position opposite to the diaphragm (59) with respect to a flow adjusting valve opening (53) described later. The flow control valve element (51) is formed in a truncated conical shape such that the diameter increases as the distance from the flow control valve port (53) increases. A passage (511) penetrating from the large-diameter end face to the side wall is formed in the flow control valve element (51), and a valve head (512) at the small-diameter end of the flow control valve element (51) is formed. ) Is opposed from the upstream side to a flow regulating valve port (53) formed on the inner periphery of a cylindrical screw (85) screwed into the valve casing (39). In addition, an annular groove (850) is provided on the outer periphery of the upstream end of the cylindrical screw (85).
And one end of a correction spring (83) formed of a coil spring is externally fitted and fixed in the annular groove (850) (corresponding to the "fixing portion" which is the invention specifying matter of the second aspect of the present invention). .
Also, in the initial state where the water circuit (81) is in the water stop state,
The flow regulating valve body (51) is farthest from the flow regulating valve opening (53), and the outer peripheral flange (515) at the upstream end of the flow regulating valve body (51) and the correction spring (83) A predetermined gap (b) is formed between the upstream end portions of the correction spring (83).
Is in a free state. This gap (b) is
And the switch-on piece (65) rod (65
a) is larger than (a), and specifically,
The dimension of the gap (b) is set to 3 mm, and the other gap (a) is set to 2.5 mm. Therefore, the rod (65a)
The correction spring (65) is not compressed until the valve abuts on the responsive valve (15), so that the supply water pressure (operating pressure) for opening the responsive valve (15) can be reduced. Therefore, the ignition operation of the gas burners (21) (21) described later in conjunction with the valve opening operation of the response valve (15) can be reliably performed. That is, contrary to the above, if the correction spring (65) is compressed before the response valve (15) opens and exerts an urging force, the urging force makes it difficult for the response valve (15) to open, As a result, the working water pressure (water pressure required to open the response valve (15)) increases. Therefore, in such a case, the operation of igniting the gas burners (21) and (21) is not performed smoothly. However, in the above-described embodiment of the present invention, the gas burners (21) ( ) Is smoothly and reliably performed.

The spring constant of the correction spring (83) is larger than the spring constants of the valve closing spring (69) for the response valve (15) and the return spring (71) for the switch closing piece (65). Although this is set to a value, a specific value of this spring constant will be described later. A valve shaft (63) projecting from the downstream end of the flow regulating valve body (51)
A spring receiving disk (60) concentric with the shaft is connected to the downstream end of the spring receiving disk (60), and a spring receiving disk (60) is provided between the spring receiving disk (60) and the cylindrical screw (85). ) Is interposed with a pressing spring (86) for loosely pressing a diaphragm (59) described later. The spring constant of the pressing spring (86) is set to a value smaller than the spring constant of the correction spring (83).

The diaphragm (59) is stretched so as to close an opening (30) formed in the side wall of the valve casing (39), and a bead (5) on the outer periphery of the diaphragm (59) is provided.
The portion (91) is squeezed and held by the constituent walls of the lid (88) and the valve casing (39). A guide cylinder (89) protruding from the outer surface of the lid (88) has a rod (6) for driving the responsive valve (15).
4) penetrates slidably.

The space surrounded by the diaphragm (59) and the lid (88) becomes the secondary pressure chamber (57), and is formed on the opposite side of the secondary pressure chamber (57) across the diaphragm (59). The space being used is a primary pressure chamber (55). Therefore, the surface of the diaphragm (59) on the side of the primary pressure chamber (55) serves as a pressure receiving surface which is an invention-specifying matter of the first aspect of the present invention. It is located.

[Regarding Hot Water Amount Control Valve (77)] The hot water flow control valve (77) disposed downstream of the diaphragm (59) is
A notch (78) is opened in the side wall of the cylindrical body, and when the tapping amount control valve (77) is rotated clockwise from the state of FIG. 2, a valve seat (82) formed in the water circuit (81) is formed. ) Is blocked by the peripheral side wall of the flow control valve (77), thereby decreasing the amount of water supplied to the heat exchanger (24) downstream of the water governor (31) and reducing the amount of hot water. Become.

[Regarding the throttle section (61)]
The throttle (61) formed on the downstream side of (77) is a conical cylinder (6
6), and a window (660) formed on the side wall of the conical cylinder (66) communicates with the above-described secondary pressure chamber (57) through a communication passage (62), whereby The water pressure reduced by a constant pressure by being throttled by the throttle section (61) is transmitted to the secondary pressure chamber (57).

A water outlet (79) located downstream of the conical cylinder (66) is configured to be connected to a heat exchanger (24) via a water circuit (26) as shown in FIG. ing. [Explanation of Operation] Next, the operation of the above-mentioned water pressure responsive gas valve will be described. In the initial state where the hydraulic pressure-responsive gas valve is not operating,
The diaphragm valve (45) is in the closed state, and the water pressure in the diaphragm cover (74) is increased by the leak hole (431).
It matches the water pressure in 1).

When the operation button (35) provided on the operation section on the front of the water heater is pushed in, the valve opening lever (33) is pushed by the tip (36) of the operation button (35) in the same manner as in the prior art. ) Is pushed, the valve opening lever (33) rotates, and the valve shaft (411) connected to the output end of the valve retreats against the urging force of the spring (48) to retract the pilot hole. (46) is opened, and the water pressure in the diaphragm cover (74) decreases. Then, due to the pressure difference between the inside of the diaphragm cover (74) and the water circuit (81), the diaphragm (43) for the diaphragm valve (45) is deformed inside the diaphragm cover (74) to operate. Is separated from the valve port (413), whereby the valve port (413) is opened.

As a result, the water inlet (73) of the water governor (31) →
Valve port (413) of water flow cylinder (47) → flow rate control valve port (53) on the downstream side of water flow cylinder (47) → primary pressure chamber (55) → hot water supply amount control valve (77) → throttle section (61) → Water flows through the path of the water outlet (79), and then the water is supplied from the heat exchanger (24) to the shower head (28).
When a water flow is generated in the throttle section (61), the water pressure on the downstream side of the upstream side of the throttle section (61) drops by a certain pressure, and the pressure drop is reduced via the communication passage (62) to the secondary pressure chamber (57). ). Then, the diaphragm (59) is deformed toward the secondary pressure chamber (57), and the rod (64) moves in the direction of the deformed operation to move the response valve (15).
Is opened against the urging force of the valve closing spring (69). In this case, in the initial state before the water flow is generated in the water circuit (81) in the water governor (31), the outer peripheral flange (5) at the upstream end of the flow regulating valve body (51) is used.
15) does not come into contact with the correction spring (83).
Is not acting on the flow regulating valve element (51), there is no fear that the correction spring (83) will hinder the smooth deformation operation of the diaphragm (59), and the correction spring (83) does not include the correction spring (83). The diaphragm (59) deforms and the responsive valve (15) is opened with the same smoothness as the conventional one. When the flow regulating valve (51) moves following the deformation of the diaphragm (59) and the outer peripheral flange (515) at its upstream end abuts against the compensating spring (83), the responsive valve is actuated.
(15) becomes the ignitable opening (the opening that can supply a sufficient amount of gas to burn the gas burner (21)). After the correction spring (83) comes into contact with the outer peripheral flange (515), the responsive valve (15) is opened to a certain degree (an opening capable of supplying a sufficient amount of gas to burn the gas burner (21)). Degree), and even if the response valve (15) further increases in opening thereafter, the increase in the opening hardly affects the increase in the amount of gas flowing through the response valve (15). Then, after the response valve (15) has reached the above-mentioned ignition possible opening degree, as described above, the flow regulating valve body (51)
The outer peripheral flange (515) abuts against and compresses the correction spring (83), and as shown in FIG. 3, the valve head (512) of the flow control valve body (51) is inserted into the flow control valve port (53). Is partially inserted,
In this state, the subsequent hot water supply operation proceeds.

When the response valve (15) is opened by the deformation operation of the diaphragm (59), the limit switch (67) pressed by the switch closing piece (65) fixed to the rod (64). Arm (68) is in a non-pressed state, and the limit switch (67) is turned ON. Then, by the output of the control circuit (37) for processing the ON signal, the solenoid valve (13) is opened and the ignition electrode (75) is spark-discharged to cause the gas burner (21).
Burns. Thereby, hot water flows out of the shower head (28).

In the above hot water supply state, when the water supply pressure in the water supply pipe connected to the water inlet (73) of the water governor (31) rises, the increased water supply pressure acts on the flow regulating valve body (51). An attempt is made to reduce the opening of the flow control valve port (53). However, in the above, the correction spring (83) is provided with the flow regulating valve body (51).
Abuts against the outer peripheral flange (515) of the correction spring (83).
The flow control valve body (51) is prevented from being excessively closed by the urging force. Therefore, in the hydraulic pressure-responsive gas valve according to the above-described embodiment, the shower head (28) does not work when the water supply pressure rises as in the above-described conventional device without the correction spring (83).
Inconveniences such as a decrease in the amount of hot water from the furnace can be avoided.

In order to keep the amount of hot water from the shower head (28) constant irrespective of a change in water pressure in the water supply pipe on the upstream side connected to the water inlet (73), the spring constant of the correction spring (83) is set. Must be set as follows. That is, the area of the pressure receiving surface of the flow regulating valve element (51) is set to 64 mm ² , and the mounting spring (8
6), the spring constant of the valve closing spring (69) and the spring constant of the return spring (71) are each set to 0.
In the case of 05 kg / mm, 0.13 kg / mm, and 0.05 kg / mm, the spring constant of the correction spring (83) should be 1.17 kg / mm or more.
The free length of the compensating spring (83) is set to about 9.2 mm, and the length of the compensating spring (83) in the compressed state (hot tap state) is about 6.3.
It is necessary to set the dimensions of each part to be mm. In this case, even if the water supply pressure on the side of the water supply pipe connected upstream of the water governor (31) changes in the range of about 50 kpa to 785 kpa, the flow control valve port (53) and the flow control valve
It was confirmed that the gap of (51) became about 0.18 mm and the flow rate was maintained at 5 liter / min. That is, it was confirmed that even if the water supply pressure changed within the above range, it was possible to prevent a decrease in the flow rate in the water circuit (26). If the spring constant of the correction spring (83) is set to 0.64 kg / mm or more, even if the water supply pressure changes in the above range, the water circuit (26) is compared with the case where the correction spring (83) is not provided. The decrease in the flow rate in parentheses) can be suppressed.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an instantaneous water heater incorporating a hydraulically responsive gas valve according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a water governor portion of the hydraulic pressure-responsive gas valve according to the embodiment of the present invention.

FIG. 3 is a sectional view of an operating state of the hydraulically responsive gas valve according to the embodiment of the present invention.

FIG. 4 is an explanatory view of a conventional example.

[Explanation of symbols]

 (21) Gas burner (11) Gas circuit (59) Diaphragm (15) Response valve (51) Flow control valve (53) Flow control valve port (83) Correction spring

Claims (4)

[Claims] A response valve (15) disposed in a gas circuit (11) to a gas burner (21) and opening and closing in conjunction with a deformation operation of a diaphragm (59) disposed in a water circuit. The diaphragm (59) is stretched so that a pressure receiving surface thereof is exposed in the water circuit, and is formed at a portion facing the pressure receiving surface in the water circuit. And a direction in which the flow control valve port faces the flow control valve port from the side opposite to the diaphragm (59) and moves toward and away from the flow control valve port following the deformation operation of the diaphragm (59). The flow regulating valve body (51) that moves to, is maintained in a free state until the flow regulating valve body (51) approaches a predetermined distance from the fully open position to the flow regulating valve port, and after approaching the predetermined distance, A correction spring for urging the flow control valve body (51) in a direction away from the flow control valve port. Pressure responsive gas valve for. 2. The hydraulic pressure according to claim 1, wherein the correction spring is a coil spring interposed between the flow regulating valve body (51) and a fixed portion formed downstream of the flow regulating valve body (51). Responsive gas valve. 3. The pressure receiving area of the flow regulating valve body (51) is 64 mm ^2.
, The spring constant of the correction spring is 0.64 Kg /
The hydraulically responsive gas valve according to claim 1 or 2, wherein the valve is set to not less than mm. 4. The predetermined distance is equal to or longer than a distance between two points between a position of the flow regulating valve body (51) when the response valve (15) is opened and a fully opened position of the flow regulating valve body (51). The hydraulically responsive gas valve according to any one of claims 1 to 3, wherein