JP2001050592A - Hot blast generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate replacement of a burner head in a site and improve maintainability by enabling a burner head a having combustion blower, a fuel pump, a fuel-jetting nozzle, an ignition plug and an igniter incorporated therein to be installed in a combustion chamber with a coupling by one touch operation. SOLUTION: A hot blast generator suitable for a rail point snow-melting system for railroad has a blower 2 rotated by an AC motor 1 disposed in the front portion of an outer housing 6 to supply air passing between the outer housing 6, the burner head 4 and combustion chamber 5 by its revolution. In this case, the burner head 4 has a unit constitution in which a DC motor 7, a hall sensor 9, a fuel pump 10, a nozzle 11, an igniter 12, a plug 13, a flame sensor 14 and the like are integrally assembled, and is detachably attached to the combustion chamber 5 through a V band coupling 17 by one touch operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot-air generator, and more particularly to a hot-air generator suitable for use as a hot-melt hot-air supply source using kerosene as a fuel, which is used in a snow-melting device at a railway rail point.

[0002]

2. Description of the Related Art FIG. 2 shows an example of a conventional hot air generator used as a supply source of hot air for snow melting. An AC motor 1 is disposed in front of an outer housing 6 shown in the figure, and a blower 2 and a fuel pump 10 are rotationally driven on both sides of a rotation shaft thereof.
The blower 2 rotates while maintaining a predetermined interval between the blower 2 and the casing 3, and sends in the combustion air guided by the air guide 20 and the blowing air passing between the outer housing 6 and the conversion chamber 5.

[0003] The fuel pump 10 also starts rotating together with the blower 2, the fuel is pressurized, and the solenoid valves 24 and 25 are started.
Is opened, fuel is sprayed into the combustion chamber 5 from the tip of the nozzle 11. Next, when the transformer 22 is energized, discharge starts at the tip of the plug 13, and ignition occurs in the combustion chamber 5 to start combustion.

[0004] The combustion gas is discharged from the tip of the combustion chamber 5 and merges with the air to be blown to generate enormous hot air and is discharged from the tip of the outer housing 6. The completion of the ignition and the start of the combustion are detected by the frame sensor 14 composed of CdS, and the energization of the transformer 22, that is, the discharge of the plug 13 is stopped.

[0005] Combustion is controlled by two-stage switching between Hi and Lo. That is, by closing the solenoid valve 24,
The fuel is depressurized through the orifice 23 of the bypass circuit,
The Lo operation is performed by controlling the solenoid valve 21 to adjust the flow rate of the combustion air. In the case of Hi operation, the solenoid valve 24 is opened, and the solenoid valve 21 is also controlled to increase the flow rate.

[0006]

In the above-described hot air generator, since the air pressure of the blower 2 for sending the combustion air and the air for blowing is low, the change in the air amount due to the fluctuation of the pipe resistance is large.
There is a problem that it is difficult to stabilize combustion performance. In addition, since the switching between the Lo operation and the Hi operation is performed mechanically, mechanical driving parts are required, the structure becomes complicated, and the variation in the flow rate and the pressure becomes large, so that fine control cannot be performed. was there.

Further, since the functional components are dispersedly arranged and the heater body is difficult to disassemble, repair on site cannot be performed, and the heater body must be replaced when a failure occurs. In addition, because of its heavy weight and large size, it cannot be transported by one person, making maintenance difficult.

Further, the safety device has only a frame sensor that detects misfiring and combustion interruption, and there is a problem that even if any trouble occurs, an abnormality cannot be detected as long as combustion continues.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it is an object of the present invention to provide a hot air generator capable of performing stable combustion control with a small number of mechanically driven components.

It is another object of the present invention to provide a hot air generator which is compact, lightweight, easy to maintain, and capable of reliably detecting an abnormal situation.

[0011]

Means for Solving the Problems A hot air generator according to the present invention comprises:
A burner head incorporating a combustion blower, a fuel pump, a fuel injection nozzle, an ignition plug, and an igniter is attached to a combustion chamber with a coupling and can be detached and attached with a single touch.

In the hot air generator, the rotation of a DC motor for driving the combustion blower is controlled by PWM control using a microcomputer and a Hall sensor, and the fuel pump is an electromagnetic pump having a regulator and a pressure switching valve built therein. And the two-stage combustion control is performed stably.

Further, in each of the above-mentioned hot air generators, a pressure switch for detecting a blockage of an intake duct or a stop of a blower for blower is mounted on an outer housing, and a thermostat for detecting overheating of a device is mounted on a burner head.

Further, in each of the hot air generators,
-By using a DC converter, the burner control
This is performed with the C power supply.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A hot air generator according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view showing a hot air generator according to an embodiment of the present invention. An AC motor 1 is disposed in front of an outer housing 6 shown in the drawing, and blowers 2 are mounted on both sides of a rotating shaft thereof and are driven to rotate. The blower 2 rotates while maintaining a predetermined interval between the blower 2 and the casing 3, and blows in air for blowing that passes between the outer housing 6, the burner head 4, and the conversion chamber 5.

A DC motor 7 is accommodated in the burner head 4, and a Wesco pump type blower 8 having a high wind pressure is fixed to a rotating shaft thereof. By driving the DC motor 7, the Wesco pump type blower 8 rotates and sends air, and the combustion air passes through the burner head 4 and is supplied into the conversion chamber 5.

The rotation speed of the DC motor 7 is detected by a Hall sensor 9, and the rotation of the DC motor 7 is controlled to a predetermined speed by PWM control of a heater control unit (HCU) having a built-in microcomputer. The burner head 4 further houses a fuel pump 10 (electromagnetic pump) having a built-in regulator valve and pressure switching valve.

When the fuel pump 10 pressurizes the fuel, the fuel is sprayed from the tip of the nozzle 11 into the combustion chamber 5. Next, by driving the igniter 12 incorporated in the burner head 4, discharge starts at the tip of the plug 13, ignites in the combustion chamber 5, and combustion starts.

The combustion gas is discharged from the tip of the combustion chamber 5 and merges with the air to be blown to generate enormous hot air and is discharged from the tip of the outer housing 6. The ignition and combustion are detected by a frame sensor 14 composed of a phototransistor, and the drive of the igniter 12 is stopped by the HCU, and the discharge of the plug 13 is stopped. The HCU controls combustion by two-stage switching between Hi and Lo. That is, H
In the case of i operation and Lo, the HCU is a DC motor 7
Is controlled to each predetermined speed, and the fuel pump 10 is controlled to each predetermined pressure.

A pressure switch 15 is mounted on the outer housing 6, and the pressure switch 15 detects the pressure inside the main body, so that it is possible to detect the blockage of the suction duct and the failure of the AC motor 1.
Further, a thermostat 16 is attached to the burner head 4, and the thermostat 16 detects the surface temperature of the burner head 4, thereby enabling detection of blockage of the suction / discharge duct and failure of the AC motor 1, and in the event of an abnormality, The HCU can safely shut down the device.

The burner head 4 has all the functional components except the AC motor 1 and the pressure switch 15 (DC motor 7, Hall sensor 9, fuel pump 10, nozzle 11,
The igniter 12, the plug 13, the frame sensor 14, and the thermostat 16) are housed therein, and in the case of a normal failure, repair can be performed only by replacing the burner head 4.

The burner head 4 is a V band coupling 1
7 and detached from the combustion chamber 5, and the one-touch coupling 18 is detached and separated from the fuel line for easy removal. In this way, by integrating related parts that have been conventionally arranged in a dispersed manner into a unit, the size and weight of the main body are reduced, and maintenance is facilitated.

[0023]

According to the hot air generator of the present invention, the influence of the pipe resistance for intake and hot air blowing on the combustion performance is minimized, and the combustion with high pipe resistance is possible.

Further, the two-stage combustion control of Hi and Lo is easily and stably performed, and the number of mechanically operating components such as a solenoid valve for controlling the blowing amount and the fuel pressure is reduced.

Further, by incorporating most of the functional components into the burner head to form a unit, the main body is reduced in size and weight, and the burner head can be replaced on site, thereby reducing the time required for repair work. I was able to. The need for transporting the main body for repairs has been eliminated, thereby reducing the number of repair staff. In addition, safety was improved by installing a pressure switch and a thermostat.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a hot-air generator according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view showing a conventional hot air generator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 AC motor 2 Blower 3 Casing 4 Burner head 5 Combustion chamber 6 Outer housing 7 DC motor 8 Wesco pump type blower 9 Hall sensor 10 Fuel pump 11 Nozzle 12 Igniter 13 Plug 14 Frame sensor 15 Pressure switch 16 Thermostat 17 V band coupling 18 One-touch type coupling 20 Air guide 21 Solenoid valve 22 Transformer 23 Orifice 24, 25 Solenoid valve

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Tsuneo Yamamoto Iwate-gun Takizawa-mura Takizawa-mura 309 Sotoyama, Tokuzawa-mura, Japan Mikniadec Co., Ltd. (72) Inventor Hiroshi Shinseki 2-2-2, Yoyogi, Shibuya-ku, Tokyo East Japan Passenger Railway F-term (reference) 3L028 AB05

Claims (4)

[Claims] 1. A hot air generator characterized in that a burner head incorporating a combustion blower, a fuel pump, a fuel injection nozzle, an ignition plug and an igniter is attached to a conversion chamber with a coupling and can be detached with a single touch. . 2. The two-stage combustion control using a microcomputer and a Hall sensor to control the rotation of a DC motor for driving the combustion blower by PWM control, and the fuel pump using an electromagnetic pump with a built-in regulator and pressure switching valve. 2. The hot air generator according to claim 1, wherein the operation is performed stably. 3. The hot-air generator according to claim 1, wherein a pressure switch for detecting blockage of the intake duct or stoppage of the blower is mounted on the outer housing, and a thermostat for detecting overheating of the device is mounted on the burner head. 4. The hot air generator according to claim 1, wherein the burner is controlled by a DC power supply by using an AC-DC converter.