JPS6153587B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention makes it possible to regulate the appropriate minimum gas flow rate for different gas types without providing a bypass circuit, and to regulate the appropriate minimum gas flow rate for each different gas type. An object of the present invention is to provide a gas proportional control valve that can accurately control the flow rate. That is, the present invention provides a spacer with a shape that does not obstruct gas flow above the valve seat that is movable in the direction of the valve axis, and adjusts the gap between the valve and the valve seat at the minimum gas flow rate by raising and lowering this spacer. This relates to a proportional control valve that divides gas types into several groups, such as liquefied petroleum gas (LPG), natural gas, and manufactured gas (city gas), and controls the gas types between the groups. The present invention relates to a gas proportional control valve that is ideal for a control device that can switch the current range and accurately control the gas flow rate.

The combustion control range for gas appliances such as water heaters and small boilers is determined by the maximum gas flow rate determined by the gas supply pressure and the resistance of the gas passage including the appliance nozzle.
Between the minimum gas flow rates determined by the burner characteristics. When controlling the amount of combustion in these gas appliances, there is a minimum limit for stable and complete combustion without blowing out due to the influence of external wind, and in order to maintain this, the minimum gas flow rate must be set. A regulating bypass circuit is provided. Since creating a bypass circuit within the valve body increases the cost accordingly, the present invention eliminates the need for a bypass circuit by providing an adjustment mechanism above the valve body to adjust the minimum valve seat clearance, thereby reducing manufacturing costs. It is possible to do this.

In order to solve the above-mentioned problems of the conventional gas proportional control valve, the present invention provides a balance between the attractive force generated by the exciting current and the repulsive force of the spring or permanent magnet, so that the valve body provided on the plunger control the position,
In a proportional control valve that controls a fluid flow rate by regulating an opening area formed between a valve body and a valve seat, the valve body is arranged without contacting a female conical valve seat, and the valve body is arranged without contacting the valve seat. A spacer having a shape that does not obstruct gas flow is fitted inside the upstream valve body so as to be able to move up and down, and the valve seat, which is in contact with the lower end of the spacer and is biased upward by the elasticity of a spring, moves up and down. A spacer lifting mechanism is provided on the upper part of the valve body, and includes a screw that can continuously adjust the minimum clearance between the valve seat and the valve body depending on the type of gas. The present invention provides a gas proportional control valve having the following configuration.

The present invention provides a gas proportional control valve having the above-mentioned configuration, in which a spacer having a shape that does not obstruct gas flow is provided above the valve seat in the valve body, and the spacer can be raised and lowered when different gas types are to be used. year,
By making it possible to adjust the gap between the valve and the valve seat at the minimum gas flow rate appropriate for different gas types, a bypass circuit is not required even when the gas type is different, and the valve is suitable for different gas types. By controlling the excitation current that determines the position of the body, that is, the degree of opening of the valve, it is possible to perform appropriate proportional control from the minimum gas flow rate to the maximum gas flow rate commensurate with the type of gas used, without replacing any parts. It is something.

Next, the present invention will be specifically explained with reference to the drawings.

As shown in FIGS. 1 and 2, the gas proportional control valve has a disk-shaped valve body 12 facing a female-conical valve seat 11 that is detachably attached inside a main body 10.
have. A solenoid 1 is installed at the bottom of the main body 10.
3, and a plunger 14 that moves up and down based on the balance between the attractive force generated by the excitation current of the solenoid and the repulsive force of the spring 15 or the permanent magnet is installed inside. The valve body 12 is attached to a valve rod 16 connected to the upper part of the plunger 14. The shape of the valve is not limited to a female conical valve, but may be a poppet valve. Gas whose pressure is controlled (secondary pressure) by a governor (not shown) enters the valve chamber from the inlet 34 of the main body 10 and enters the valve seat 1.
The flow rate is controlled by the gap between 1 and the valve body 12, and the gas is sent to a gas combustor or the like through an outlet 35.

The valve chamber formed inside the main body 10 is divided into an upper valve chamber 17, which is a small diameter portion, and a lower valve chamber 18, which is a large diameter portion.
is located. The valve seat 11 is biased upward within the valve chamber by a spring 21 provided between a guide member 20 of a plunger fitted in the lower part of the main body and the lower edge of the valve seat. Also, the small diameter portion 17 of the valve chamber
A cylindrical spacer 22 with an opening at the bottom as shown in FIG. 3 is inserted into the spacer. The lower edge of the spacer 22 is always in contact with the upper peripheral edge of the valve seat 11, and a window hole 23 is provided in the side surface corresponding to the gas inlet 34. A recess 27 is formed to hold a steel ball 26 interposed between the recess 25 and a positioning hole 29 that engages with a guide pin 28 projecting from the top wall of the main body. There is. Further, there is a horizontal screw hole 31 provided in the top wall portion 25 of the main body, and an adjusting screw 32 having a taper 33 that contacts the steel ball 26 and is screwed into the screw hole 31.
A lifting mechanism 30 for lifting and lowering the spacer 22 is configured.

In the state shown in FIG. 1, the elasticity of the spring 21 causes the valve seat 11 and the spacer 22 to rise to their respective upper limits, forming a predetermined gap between the valve seat 11 and the valve body 12. When the shutoff valve of the gas appliance is opened in this state, even if no current flows through the solenoid 13, the minimum gas flow rate flows through the gap between the valve seat and the valve body and combustion occurs. For example, when the water temperature detected by the detection unit in a gas water heater is lower than the set value,
An operation signal (control current) is output from the adjustment section in order to increase the operation amount (gas flow rate) according to the difference between the set value and the detected value. The solenoid coil is excited by this control current, the plunger 14 is attracted into the coil, and the valve body 12 is moved to a position where the spring 15 is compressed and the repulsion force is balanced with the attraction force of the solenoid.
is displaced to widen the gap with the valve seat 11 and increase the gas flow rate (operated amount). As the gas flow rate increases, the water temperature rises, and as the difference from the set value decreases, the control current (operation signal) decreases, and the repulsive force of the spring increases relative to the suction force of the solenoid. move towards
The gap between the valve body 12 and the valve seat 11 is reduced by again displacing the valve body 12 to a position where it balances with the suction force of the solenoid.

The above is a case where the operation is performed on a gas with a small calorific value per unit volume, such as production gas (4 gases). When changing the gas type to a gas with a large calorific value per unit, adjust the adjusting screw 32 and pass the spacer 22 through the taper 33 and steel ball 26.
lower. Due to the lowering of the spacer 22, the valve seat 1
1 descends against the elasticity of the spring 21, reducing the gap with the valve body 12, maintaining the minimum gas flow rate commensurate with the type of gas used, and thereafter changing it to the maximum flow rate by performing the operations described above. be.

Since the spacer 22 has a cylindrical shape with an open bottom and has a window hole 23 on the side surface, the inflow of gas is not obstructed. Also, the top wall portion 25 of the main body
Since the guide pin 28 protruding to the side is engaged with the hole 29 of the spacer top plate, positioning during assembly (aligning the opening entrance 34 and the window hole 23) and raising and lowering of the spacer are smoothly guided. Furthermore, a steel ball 26 is placed in the recess 27 in the center of the top plate,
Since the taper 33 of the adjusting screw 32 is brought into contact with the steel ball 26, the minute downward movement of the spacer can be accurately performed by the thrust of the adjusting screw 32.

4 to 6 show modifications of the spacer guide and lifting mechanism. That is, as shown in FIG. 4, there is an internal screw hole 36 formed in the center of the top wall portion 25 of the main body 10, and an adjusting screw 37 that is screwed into the internal screw hole 36 and abuts against the top plate 24 of the spacer 22. The elevating mechanism 30 is constituted by the above. The spacer 22 has a cylindrical shape with an open bottom and has a window hole 23 on the side surface, and also has a pair of protrusions 38, 38 on the side surface as shown in FIG. Projection 3
8 and 38 are engaged with guide grooves 39 and 39 (FIG. 5) formed in the vertical direction of the inner wall of the upper valve chamber 17, so in this embodiment as well, by adjusting the adjustment screw 37, The spacer 22 is moved up and down in the vertical direction, so that the gap between the valve seat 11 and the valve body 12 can be adjusted as desired.

As described above, in the present invention, a bypass circuit is not provided in the main body, and the minimum gas flow rate is regulated only by the main circuit, so that the valve and the valve seat do not come into contact with each other and always have a gap. Therefore, contact between the valve and the valve seat during the throttle stroke of the valve can be avoided or almost eliminated, and the life of the valve can be maintained for a long time. In addition, the gap between the valve and the valve seat can be easily adjusted by operating the lifting mechanism to push down the spacer and lowering the valve seat, which is given an upward tendency by the elasticity of the spring.

[Brief explanation of the drawing]

Figure 1 is a sectional front view of the proportional control valve of the present invention, Figure 2 is a front view of the proportional control valve of the present invention;
The figure is a side view, FIG. 3 is a perspective view of the spacer, FIG. 4 is a partial sectional view of a modified example, and FIG. 5 is a V--
6 is a cross-sectional view taken along the V line, and FIG. 6 is a perspective view of the spacer in FIG. 4. 10...Main body, 11...Valve seat, 12...Valve body,
13...Solenoid, 14...Plunger, 15
... Spring, 16 ... Valve rod, 17 ... Upper valve chamber, 18 ... Lower valve chamber, 19 ... Step part, 20 ...
... Guide member, 21 ... Spring, 22 ... Spacer, 23 ... Window hole, 24 ... Top plate, 25 ... Main body top wall, 26 ... Steel ball, 27 ... Recess, 28 ... Guide pin , 29... hole, 30...
Lifting mechanism, 31...Screw hole, 32...Adjust screw, 33...Taper, 34...Gas inlet, 35...Gas outlet, 36...Female thread hole, 37
...Screw, 38...Protrusion, 39...Guide groove.

Claims (1)

[Claims] 1. The position of the valve body provided on the plunger is controlled by the balance between the attractive force generated by the exciting current and the repulsive force of the spring or permanent magnet, and the valve body is formed between the valve body and the valve seat. In a proportional control valve that controls fluid flow rate by regulating the opening area of the valve, the valve body is arranged without contacting a female conical valve seat, and the gas flow is controlled inside the valve body on the upstream side of the valve seat. A spacer having a shape that does not obstruct the flow of the valve is fitted so as to be movable up and down, and the valve seat, which is in contact with the lower end of the spacer and is biased upward by the elasticity of a spring, is fitted so as to be movable up and down. A gas proportioning device characterized in that the upper part of the main body is provided with a spacer elevating mechanism equipped with a screw that can continuously adjust the minimum clearance between the valve seat and the valve body depending on the type of gas. control valve. 2 The spacer has a cylindrical shape with an open bottom,
The top plate has a guide hole for positioning, and the side part has a window hole for gas inflow.The spacer's elevating mechanism uses a steel ball placed in the center of the spacer's top plate, and a steel ball from the top of the valve body. A gas proportional control valve according to claim 1, comprising a tapered screw brought into contact with the gas. 3 The spacer has a cylindrical shape with an open bottom,
The side part has a window hole for gas inflow and a pair of protrusions that engage with the guide groove formed in the upper valve chamber, and the spacer lifting mechanism is formed in the center of the top wall of the main body through an internal threaded hole. 2. The gas proportional control valve as set forth in claim 1, comprising: and an adjusting screw which is screwed into the female threaded hole and comes into contact with the top plate of the spacer.