JP2000161781A - Gas hot-water supplier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the failure of movement of a spindle even when a spindle supporting unit, made of a resin, is clamped by an excessive torque from a direction orthogonal to the axial direction of the spindle. SOLUTION: In a connecting structure, connecting a spindle supporting unit 31, made of a resin and supporting a spindle 22 so as to be free of advancing and retreating, to a gas side casing 9 by clamping the supporting unit 31 from a direction orthogonal to the axial direction of the spindle 22 by a cone point screw 33, the spindle supporting unit 31 is provided with an air gap unit 38, formed on the clamping direction of the cone point screw 33, whereby the air gap unit 38 is deformed and absorbs an excessive torque when the cone point screw 33 is screwed with an excessive clamping torque and therefore, the penetrating hole 29 of the spindle 22 will not be deformed into an elliptical shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas water heater, and more particularly, to a connection structure between a spindle support portion of a water pressure responsive device formed of a resin material and a gas side casing.

[0002]

2. Description of the Related Art Conventionally, in order to open and close a gas passage in conjunction with water flow to a gas water heater, a water pressure responsive device that operates by a differential pressure due to water flow and the operation of the water pressure responsive device are transmitted. A spindle and a water supply automatic gas valve that opens and closes a gas flow path are provided at a tip of the spindle. Generally, as shown in FIG. 4, the water pressure responsive device is connected to the gas side casing 9 by a single pointed screw 33 so that it can be easily attached and detached in order to facilitate maintenance. That is, the connection between the water pressure response device 10a and the gas side casing 9 is made by the spindle support portion 31a of the water pressure response device 10a.
Is inserted into the connecting portion 30 of the gas side casing 9, and one pointed screw 33 is screwed into the recess 32 of the spindle support portion 31 a from a direction perpendicular to the axial direction of the spindle 22. In addition, the spindle support 31
A metal material such as brass or bronze has been conventionally used for the casing lid 20 that forms a. However, a resin material has begun to be used instead of the metal material in order to reduce the weight and manufacture it at low cost.

[0003]

However, if the casing lid 20, which is the connecting portion of the hydraulic pressure responsive device 10a, is made of resin, when the pointed screw 33 is screwed with an excessive screwing torque, the insertion hole of the spindle 22 is inserted. 29 may be deformed into an elliptical shape, and the spindle 22 may not operate smoothly. In other words, if the sliding resistance between the insertion hole 29 and the spindle 22 becomes larger than the forward / backward force acting on the spindle 22, the spindle 22 cannot move forward and backward, and the automatic water supply gas valve cannot be opened and closed. Therefore, the gas water heater of the present invention solves the above problems,
It is an object of the present invention to prevent the spindle from being damaged even if the spindle support is made of a resin material and is tightened with an excessive tightening torque from a direction perpendicular to the axial direction of the spindle.

[0004]

According to a first aspect of the present invention, there is provided a gas water heater having a diaphragm provided in a water supply passage from a faucet to a heat exchanger by passing water to the heat exchanger. A water pressure difference occurs between the primary room and the secondary room partitioned by
A water pressure responsive device for advancing a spindle inserted into the secondary chamber is provided, and a water supply for opening a gas flow path by advancing the spindle and closing the valve by retreating a gas side casing forming a gas flow path. An automatic gas valve is provided, the water pressure responsive device includes an insertion hole through which the spindle is inserted, and a resin support portion that freely supports the spindle so as to advance and retreat, in a direction orthogonal to the axial direction of the spindle. In the gas water heater connecting the support portion of the spindle to the gas side casing by the tightening means, the support portion of the spindle has a gap formed on or near the tightening direction of the tightening means. Make a summary.

[0005] In the gas water heater according to the first aspect of the present invention having the above structure, the fastening means connects the spindle support portion of the hydraulic pressure responsive device to the gas side casing. When the resin support portion is tightened by the tightening means from a direction perpendicular to the spindle axis direction, a gap formed in the support portion on or near the tightening direction line is deformed, and the tightening force applied to the insertion hole of the spindle is changed. Absorb. Therefore, even if the support portion is molded of easily deformable resin and is tightened with an excessive force from a direction orthogonal to the spindle axis direction by the tightening means, the cavity absorbs the tightening force and the spindle insertion hole becomes elliptical. Since it is difficult to deform, the sliding resistance of the spindle does not increase and the movement of the spindle is not impaired.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to further clarify the configuration and operation of the present invention described above, a preferred embodiment of a gas water heater of the present invention will be described below. FIG. 5 is a schematic diagram of a gas water heater, in which a water flow control unit is provided at a water inlet. The water flow control unit includes, from the upstream, a faucet 24 for opening and closing the water supply path 3 from the water inlet, a water pressure responsive device 10 for opening and closing the gas flow path in conjunction with the flow of water, and a hot water by changing the amount of water. A hot water temperature controller 11 for controlling the temperature and a venturi 2 described later are incorporated in a resin housing.

The hydraulic pressure responsive device 10 is provided with a diaphragm 12 that is movable back and forth, and a primary chamber 16 and a secondary chamber 21 are formed by dividing the diaphragm 12. A casing lid 20 for holding the diaphragm 12 is fixed to a water-side casing 8, which is a housing of the water flow control unit, by a screw (not shown), and a flow path to the primary chamber 16 of the water-side casing 8 is coaxial with the diaphragm 12. A water governor 14 is provided to keep the flow rate constant even when the supply water pressure fluctuates, and a hot water temperature controller 11 is provided downstream of the primary chamber 16. In the hot water temperature control unit 11, the flow path includes a heating path 7a that passes through the venturi 2 to the heat exchanger 1 and then to the mixing unit 6, and a bypass path 7b that directly flows to the mixing unit 6.
Branched to The branched flow paths join at the mixing section 6 and reach the hot water outlet via the hot water supply path 5. Also,
The venturi 2 provided in the heating path 7a narrows the flow path and has a horizontal hole 2a in a direction perpendicular to the flow path. Then, the secondary chamber 21 of the hydraulic pressure response device 10 is
Is provided. The diaphragm 12 has a spindle 22 and a push shaft 37 for transmitting displacement.
Are provided in contact with the same axis, and the other end of the push shaft 37 is provided with an automatic water supply gas valve 23 urged in a backward direction by a spring (not shown).

In the gas supply path 4 to the burner 27, an instrument plug 26 for opening and closing the gas passage and a main valve 25 are provided upstream of the automatic water supply gas valve 23. Further, a burner 27 that burns the fuel gas is provided downstream of the automatic water supply gas valve 23, and an electrode (not shown) that discharges the burner 27 and ignites the fuel gas is provided.

The hydraulic pressure responsive device 10 is incorporated in a water-side casing 8 integrally formed of a resin material, and a casing lid 20 screwed to the water-side casing 8 is similarly formed of a resin material.

As shown in FIG. 1, the casing lid 20 is provided with a convex spindle support portion 31 (φ16 mm), and an insertion hole 29 (φ2 mm) through which the spindle 22 is freely inserted into the center axis. Is opened, and a conical recess 32 is provided on the outer peripheral surface (the lower side in the figure). Further, the gas-side casing 9 connected to the water-side hydraulic pressure responsive device 10.
, A cylindrical connecting portion 30 into which the spindle support portion 31 is inserted, and a push shaft 37 for pushing and opening the automatic water supply water gas valve 23 on the center axis, facing the back of the connecting portion 30, On the outer side of the connecting portion 30, a pointed screw 3 whose tip is conically pointed toward the central axis from a direction perpendicular to the central axis (downward in the figure).
3 is screwed. When the recessed portion 32 of the spindle support portion 31 is inserted into the connecting portion 30 so as to match the leading end position of the pointed screw 33 and the pointed screw 33 is screwed, the tip of the pointed screw 33 is pressed into the recessed portion 32. Then, the hydraulic pressure responsive device 10 and the gas side casing 9 are connected. Further, when connected, the spindle 22 which advances and retreats by the hydraulic pressure responsive device 10 and the push shaft 37 which opens and closes the automatic water supply gas valve abut on the same axis.

The spindle support 31 of the casing lid 20
As shown in FIG. 2 and FIG. 3, a reinforcing portion 34 protruding from the end on the side of the concave portion 32 (the lower side in the drawing) is provided, and a 10.5 mm depth substantially radially extends around the central axis from the end. There are provided meat fillets 36a, 36b, 36c, 36d (hereinafter, referred to as "meat fillet 36" when no distinction is made). Due to this meat thread 36, substantially radial ribs 35a, 35b, 35c (3 mm in width) are formed in the spindle support portion 31 from the ends in the axial direction. , 35b and the rib 3 extending upward
5c forms an inverted T-shaped rib (hereinafter, referred to as "rib 35" when not distinguished). That is, the meat fillet 36 is located between the ribs (between 35a to 35c, 35c
To 35b) and between the reinforcing portion 34 and the rib (35a to 34b).
(Between 35b and 34b). In the middle of the rib 35c extending upward from the central axis, 1.5 mm from the end.
A groove-shaped gap 38 having a depth is provided across the rib 35c.

The connection between the hydraulic pressure responsive device 10 and the gas side casing 9 is made by a single pointed screw 33 so that the hydraulic pressure responsive device 10 can be easily detached from the gas side casing 9 for easy maintenance. . When the pointed screw 33 is screwed, the gap 38 provided at the end of the spindle support portion 31 is deformed to absorb an excessive screwing force of the pointed screw 33. For this reason, even if the pointed screw 33 is screwed with an excessive screwing torque, the spindle insertion hole 29 is unlikely to be deformed into an elliptical shape, and the so-called cylindricity of the insertion hole 29 is not impaired. For example, according to data obtained experimentally, even when tightening with an excessive tightening torque of 20 kg · cm exceeding the tightening torque by manual power, when the gap portion 38 is not provided,
While the diameter of the insertion hole 29 was deformed by 2.5%, when the gap 38 was provided, the deformation could be limited to 1% or less. This deformation amount is smaller than a gap formed between the outer diameter of the spindle 22 and the inner diameter of the insertion hole 29, and is a deformation amount that does not cause sliding resistance due to the tightening force.

Next, the operation of the water pressure responsive device 10 of the water heater will be described (FIG. 5). When the ignition operation is performed, the instrument plug 26
The faucet 24 is opened together with the main valve 25. When the water passes through the venturi 2 via the hydraulic pressure responsive device 10, the pressure in the secondary chamber 21 decreases in accordance with the decrease in the water pressure in the lateral hole 2a due to the venturi effect. Then, a differential pressure is generated between the primary chamber 16 and the secondary chamber 21 to generate a moving force (to the left in the drawing) on the diaphragm 12 which can be moved back and forth, and the moving force is transmitted to the spindle 22 and the push shaft 37. Then, the water supply automatic gas valve 23 is opened, and the gas flow path is opened.

When the faucet 24 is closed to stop tapping water from this state, the water flowing through the water supply path 3 toward the heat exchanger 1 is stopped, and the water pressure responsive device 10 is connected to the diaphragm 12.
The differential pressure between the primary chamber 16 and the secondary chamber 21 disappears,
7 is retracted to the stop position (right direction in the figure), the automatic water supply gas valve 23 is closed, and the gas flow path is closed. As described above, in order to efficiently transmit the moving force between the hydraulic pressure responsive device 10 and the automatic water supply gas valve 23, the transmission loss due to the sliding resistance must be minimized. Therefore, the gap 38 provided in the spindle support portion 31 does not increase the sliding resistance of the spindle 22 inserted into the insertion portion 29 and does not impair the movement of the spindle 22. For example, in the gas water heater, the safety is improved because the spindle 22 does not stop on the way to advance and retreat and the water supply automatic gas valve 23 is not left open.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments at all, and it is needless to say that the present invention can be implemented in various modes without departing from the gist of the present invention. It is. For example, the shape such as the depth and the width of the gap 38 varies depending on the size of the spindle support 31 and the hardness of the resin material.

[0016]

As described in detail above, according to the gas water heater of the present invention, when the hydraulic pressure responsive device is connected to the gas side casing, the spindle support portion is made of resin, and the axial direction of the spindle is increased. Even when the spindle is tightened with an excessive force from a direction perpendicular to the direction, the insertion hole of the spindle is hardly deformed into an elliptical shape, so that an excellent effect that the sliding resistance of the spindle does not increase and the movement of the spindle is not impaired is exerted.

[Brief description of the drawings]

FIG. 1 is a schematic view of a spindle support unit according to an embodiment of the present invention.

FIG. 2 shows a spindle support unit 31 according to the embodiment of the present invention.
FIG.

FIG. 3 shows a spindle support portion 31 according to the embodiment of the present invention.
It is a perspective view of.

FIG. 4 is a schematic view of a conventional spindle support portion 31.

FIG. 5 is a schematic configuration diagram of a water heater.

[Explanation of symbols]

 9 Gas side casing 10 Hydraulic pressure responsive device 22 Spindle 29 Insertion hole 31 Spindle support part 33 Pointed screw 35 Rib 36 Thickness 37 Push shaft 38 Void

Claims (1)

[Claims] 1. A water pressure difference is generated between a primary chamber and a secondary chamber partitioned by a diaphragm in the middle of a water supply passage from a faucet to a heat exchanger, and water is passed through the heat exchanger. A water pressure responsive device for advancing a spindle inserted into the chamber is provided, and a water supply automatic gas valve for opening a gas flow path by advancing the spindle and closing the valve by retreating a gas side casing forming a gas flow path. Wherein the water pressure responsive device includes an insertion hole through which the spindle is inserted, and a resin support portion that supports the spindle freely to advance and retreat, and tightening means from a direction orthogonal to the axial direction of the spindle. In the gas water heater connecting the support portion of the spindle to the gas side casing, the support portion of the spindle has an empty space on or near the tightening direction of the tightening means. Gas water heaters, characterized in that part is formed.