JPH01137108A - Safety device for gas burner proportional control valve - Google Patents

Abstract

PURPOSE:To enable performing combustion within the optimum combustion range without fluctuations in a mixing ratio by installing an air pressure detection means to an air blower and a gas pressure detection means to a raw gas pipe, specifying a setting value to these detection means and closing a solenoid valve when the air pressure or the gas pressure runs out of the setting value. CONSTITUTION:A rotary speed detection means R judges the rotary speed of a fan of a blower with an air detection means. A raw gas pipe P is connected to a raw gas inlet 52 of a proportional control valve 2. A solenoid valve E installed to the raw gas pipe P, a governor V installed to the downstream side of the solenoid valve E, a gas pressure switch S installed to the downstream side of the governor are used as a gas pressure detection means. When a setting value is determined and the rotary speed of the fan or the raw gas pressure runs out of the setting value, both the rotary speed detection means R and the pressure switch S close the solenoid valve E. The pressure switch can be used as a combustion air pressure detection means.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a safety device used in a ratio control valve of a gas burner.

[Prior art]

Pressurized air is supplied to the gas burner as combustion air. If the supply of pressurized air decreases, incomplete combustion will occur, so conventional gas burners are provided with a detection means for detecting the air pressure of pressurized air.

[Problems with conventional technology]

By the way, when supplying a mixture (a mixture of raw gas and air) to a burner, a ratio control valve may be used to optimally set the ratio of raw gas and air.

In this case, if the gas pressure of the raw gas supplied to the ratio control valve or the air pressure of the combustion air changes, the mixing ratio between the amount of raw gas and the amount of air changes, making it impossible to ensure combustion under optimal conditions. This was an inconvenience.

[Means for solving the above problems]

This invention was made to eliminate the above-mentioned disadvantages, and its configuration includes a gas burner and a ratio control valve that adjusts the amount of air mixture supplied to the gas burner, and the ratio control valve is provided with air. An inlet and a raw gas inlet are provided, a blower is installed in the air inlet, a raw gas pipe is connected to the raw gas inlet via a solenoid valve, and the blower is actuated to control the ratio control valve. In the ratio control valve of a gas burner that supplies pressurized air and raw gas to the ratio control valve via the raw gas pipe, the blower is provided with an air pressure detection means, and the raw gas pipe is provided with a gas pressure detection means. and setting values for these detection means, and closing the solenoid valve when the air pressure of the blower or the raw gas pressure of the raw gas pipe becomes outside the set value. This is a safety device for valves.

[Action of the invention]

Since the safety device for a ratio control valve of a gas burner according to the present invention is configured as described above, in other words, the blower is provided with an air pressure detection means, the raw gas pipe is provided with a gas pressure detection means, and the gas pressure detection means is provided in the raw gas pipe. A set value is set in the means, and the solenoid valve is configured to close when the air pressure of the blower or the raw gas pressure of the raw gas pipe becomes outside the set value, so that the raw gas and combustion air are It is always supplied to the ratio control valve at a predetermined pressure.

[Explanation of Examples]

Embodiments of the present invention will be described below based on the drawings.

In describing the embodiment, first, a ratio control valve used in a gas water heater will be described.

In Figure 1, 1 is a part of the burner of a gas water heater, 2
is a ratio control valve, which controls the amount of raw gas, the amount of primary air, and the amount of secondary air supplied to this burner part 1. The burner part 1 and the ratio control valve 2 are integrated by a box 3.

Reference numeral 31 denotes an air introduction port, which is integrally formed with the ratio control valve 2. This air inlet 31 has an outlet 41 for the blower 4.
are connected. Further, 5 is a support tube, which is fitted onto the side surface of the case 3. This support cylinder 5 opens into the case 3, and the inside thereof functions as a raw gas chamber 51. 52 is a raw gas introduction path, which is formed in the support cylinder 5. This raw gas introduction path 52 guides raw gas into the raw gas chamber 51 from the outside. Reference numeral 6 denotes a cylindrical valve face member, which is fitted inside the support tube 5. The rear end of this valve face member 6 passes through the support tube 5. Reference numeral 61 denotes a nut, which is screwed onto the protruding portion of the valve surface member 6 and fixes the valve surface member 6 by a so-called double NAND structure. Reference numeral 62 denotes an annular valve seat, which is fixed to the tip opening of the valve face member 6. The function of this valve seat 62 will be described later. Reference numeral 62 designates a shaft hole bored in the right end portion of the valve face member 6, and reference numeral 7 designates an operating rod fitted into the shaft hole 63 so as to be movable forward and backward. Further, 71 is a valve body, which is integrally formed in the middle of the operating rod 7. The outer wall surface of this valve body 71 is formed in a tapered shape, and together with the annular valve seat 62 constitutes the raw gas amount control valve G of the present invention. The raw gas amount control valve G adjusts the amount of raw gas passing through by increasing and decreasing its opening area by moving the operating rod 7 back and forth.

Next, 32 is a partition wall, which is fixed to the box 3. This partition wall 32 partitions the inside of the box 3 into a primary air chamber 321 and a secondary air chamber 322. Reference numeral 33 denotes an annular valve seat, which is fitted into the partition wall 32. The inner wall surface of this valve seat 33 is tapered.

Reference numeral 8 denotes a retractable cylinder, which is fitted into the support cylinder 6 so as to be retractable and retractable. This reciprocating cylinder 8 is fixed to the left end of the operating rod 7, and moves forward and backward based on the movement of the operating rod 7. Reference numeral 81 denotes a disk-shaped valve body, which is integrally formed at the right end of the reciprocating cylinder 8. This valve body 81 is connected to the primary air chamber 32 together with the valve seat 33.
1.

The primary air amount control valve A increases or decreases its opening area by moving the operating rod 7 back and forth, thereby adjusting the amount of primary air flowing into the secondary air chamber 321. . Further, 811 is a raw gas ejection passage, which is formed radially in the valve body 81.

This raw gas jetting passage 811 communicates the inside of the reciprocating cylinder 8 with the primary air chamber 321 and jets raw gas into the primary air chamber 321 . - The raw gas flowing into the primary air chamber 321 mixes with primary air within the primary air chamber 321.

Next, 9 is a fixed cylinder, which is fixed to the case 3. This fixed cylinder 9 partitions the inside of the box 3 into a compressed air chamber 91 and the secondary air chamber 322.

92 is a valve cylinder, which connects the valve body 81 via a connecting piece 911.
It is integrally formed with the protruding part of. This valve cylinder 92 is fitted into the fixed cylinder 9 so as to be able to move forward and backward, and by moving forward and backward, the opening area between the partition wall 32 and the valve cylinder 92 is increased or decreased. That is,
The valve cylinder 92 and the fixed cylinder 9 constitute the secondary air amount control valve B of the present invention, and as the operating rod 7 moves back and forth, the secondary air chamber 3
Adjust the amount of secondary air flowing into 2. Note that 921 is a return spring for returning the operating rod 7 to its original state.

Next, 11 is a burner head plate of the burner part 1.

The inside of this burner head plate 11 communicates with the primary air chamber 321 of the control section 2. 111, 111, . . . are flame ports, which are bored in the burner head plate 11. This flame outlet 111, 111. ... causes the air-fuel mixture to be jetted out to the outside of the burner head plate 11. This spouted air-fuel mixture is ignited to form an internal flame.

12 is a secondary air pipe, which is installed above the burner head plate 11. This secondary air pipe 12 communicates with the secondary air chamber 322 of the control section 2. 12), 121
．． . . . are pores, which are bored into the secondary air pipe 12. These pores 12), 121, . . . blow out secondary air above the inner flame. This ejected secondary air helps the combustion of the air-fuel mixture and forms an outer flame H above the inner flame. 13
is a heat exchanger, which is installed above the outer flame H. This heat exchanger 13 heats water to turn it into hot water.

To explain the operation of the ratio control valve, the operating rod 7 is moved to the left by an appropriate actuator,
That is, when pushed in, the opening areas of the raw gas amount control valve G, the secondary air amount control valve A, and the secondary air amount control valve B become larger.

Therefore, as a result of an increase in the amount of air-fuel mixture and secondary air supplied to the burner part 1, the amount of combustion heat in the burner part 1 increases. Then, when the operation of the actuator ends,
The action of the return spring 921 causes the operating rod 7 to return to its original state.

Next, the present invention will be explained in detail.

In the figure, R is a rotation speed detection means (combustion air pressure detection means of the present invention), which determines the rotation speed of the blower fan of the blower. In addition, P is a raw gas pipe, and ratio control valve 2
It is connected to the raw gas inlet 52 of. E is a solenoid valve installed in this raw gas pipe P, ■ is a governor installed on the downstream side of this solenoid valve E, and S is a pressure switch installed on the downstream side of this governor ■ (gas pressure detection of this invention). (equivalent to means). The rotational speed detection means R and the pressure switch S have set values, and when the rotational speed of the blower fan or the gas pressure of the raw gas exceeds the set values, the solenoid valve E is closed.

Note that a pressure switch can also be used as the combustion air pressure detection means.

〔Effect of the invention〕

Since the safety device for a ratio control valve of a gas burner according to the present invention is configured as described above, in other words, the blower is provided with an air pressure detection means, the raw gas pipe is provided with a gas pressure detection means, and the gas pressure detection means is provided in the raw gas pipe. A set value is set in the means, and the solenoid valve is configured to close when the air pressure of the blower or the raw gas pressure of the raw gas pipe becomes outside the set value, so that the raw gas and combustion air are It is always supplied to the ratio control valve at a predetermined pressure.

Therefore, if this ratio control valve safety device is used, the gas pressure of the raw gas or the air pressure of the combustion air supplied to the ratio control valve will not fluctuate, so the mixing ratio between the amount of raw gas and the amount of air will be reduced. will not change. As a result, combustion can be achieved within the optimum combustion range.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of the invention. 1... Gas burner 2... Ratio control valve 31... Air inlet 4... Blower 52... Raw gas inlet E... Solenoid valve P... Raw gas pipe R... Air pressure detection means S... Gas pressure detection means patent application Koikan Kogyo Co., Ltd. 5.1
raw gas

Claims (2)

[Claims] (1), comprising a gas burner and a ratio control valve that adjusts the amount of air mixture supplied to the gas burner; the ratio control valve is provided with an air inlet and a raw gas inlet, and the air inlet is provided with an air blower. is installed, a raw gas pipe is connected to the raw gas inlet via a solenoid valve, and the blower is operated to supply pressurized air to the ratio control valve and control the ratio via the raw gas pipe. In a ratio control valve for a gas burner that supplies raw gas to the valve, the blower is provided with an air pressure detection means, the raw gas pipe is provided with a gas pressure detection means, set values are determined for these detection means, and the air pressure of the blower is determined. Alternatively, a safety device for a ratio control valve of a gas burner, wherein the solenoid valve closes when the raw gas pressure in the raw gas pipe becomes outside the set value. (2) The safety device for a ratio control valve of a gas burner as set forth in claim 1, wherein the air pressure detection means comprises rotation speed detection means of a rotating fan of a blower.