Patent Description:
At the end of the nineteenth century, aluminothermic welding was invented to weld rail tracks with the development of the metallurgical and chemical industries. To prepare aluminothermic welding for connecting two rail ends, a welding operator should heat the end faces of these rail ends opposite each other in the welding gap. This heating process aims to remove any moisture that may exist in a welding mold. Furthermore, increasing the temperature of the rail ends can slow down the cooling of the heated weld. In this way, a welding operator can obtain a desired certain metallic structure in the welding gap. However, when working at the railway tracks, a welding operator takes much effort and energy to move a conventional preheating burner equipped with an air compressor on and off the railway tracks. The conventional preheating burner is comparatively huge and heavy because the air compressor is usually disposed on the side of the preheating burner. Thus, a conventional preheating burner does not provide a thinner and lighter burning apparatus for railway repair.

German patent <CIT>, on which the two-part form of claim <NUM> is based, discloses a process for increasing the vapor pressure of liquid gases housed in steel bottles, characterized in that the bottles are heated with an artificially generated hot wind from the outside. The hot wind is generated using fuel from the liquid bottle, the vapor pressure of which is to be increased. The process consists of a funnel-like housing made of sheet iron or refractory with a gas-air mixture inlet at the top of the funnel and an inhibitor of the flow of the burning mixture, in the funnel, a certain distance from the mixture inlet, the largest part of the funnel cross-section is filled.

German utility model <CIT> discloses a preheating torch which is intended to prepare an aluminothermic weld of two rail ends spaced apart from each other at the end faces by a welding gap and which is designed for convenient operation on the laid track. Said torch consists of a housing (<NUM>), which accommodates means for forming a combustible mixture, and an outlet nozzle (<NUM>), which is intended to introduce the combustible mixture into a region to be preheated, on the end of a tubular element (<NUM>), wherein a fan is provided inside the housing (<NUM>) to supply said means with combustion air taken from the ambient atmosphere. The housing (<NUM>) is also provided with supports (<NUM>, <NUM>) for placing on the ground on either side of the rail ends to be welded and with an annular body (<NUM>) acting as a crane eye.

Chinese patent application <CIT> discloses an intelligent preheating mechanism for steel rail thermit welding. The intelligent preheating mechanism comprises a positioning clamping unit, an intelligent control system arranged on the positioning clamping unit and a combustion unit connected with the intelligent control system; the intelligent control system comprises a combustor, a control unit for controlling the combustor and a gas pipe connector communicating with the combustor; the combustion unit comprises an air inlet pipe communicating with the combustor, and a combustion nozzle communicating with the other end of the air inlet pipe; and the positioning clamping unit comprises a main support, a steel rail positioning and locking support which is arranged on the main support and used for locking the mechanism on a steel rail, a thermit welding sand mold locking device which is used for locking a thermit welding sand mold on the steel rail and a preheating position adjusting device which is used foradjusting positions of the combustion nozzle. According to the intelligent preheating mechanism, various parameters of the steel rail preheating can be strictly and accurately controlled, various factors easily causing poor preheating in the steel rail thermit welding preheating process are reduced or eliminated, and steel rail preheating effect is improved.

The objective of the present invention is to provide a burning apparatus for railway repair, and more particularly a burning apparatus that provides a thinner and lighter burning apparatus for railway repair.

The following summarizes some aspects of the present invention to provide a basic understanding of the technology discussed. This summary is not an extensive overview of all contemplated features of the invention, and is intended neither to identify key or critical elements of all aspects of the invention nor to delineate the scope of any or all aspects of the invention. Its sole purpose is to present some concepts of one or more aspects of the invention in a summary form as a prelude to the more detailed description that is presented later.

The present invention is defined in claim <NUM>, which provides a burning apparatus for railway repair, defining an axis and comprising: an air compressor assembly including an inlet opening and an outlet opening, and a combustion assembly connected to the outlet opening of the air compressor assembly, wherein the air compressor assembly and the combustion assembly are axially disposed along the axis, and wherein the air compressor assembly compresses air into the combustion assembly.

The air compressor assembly further comprises: a body axially disposed along the axis, a motor including a motor shaft and disposed in the body, and a propeller driven by the motor through the motor shaft and guiding air into the body.

The invention is characterised in that the body comprises: an outer housing, and an inner housing disposed in the outer housing and connected to the outer housing, the motor disposed therein, wherein the inner housing and the outer housing defining an air passage therebetween, and the propeller guides air from the air compressor assembly into the combustion assembly through the air passage.

Further aspects of the present invention are specified in the dependent claims.

Advantageously, the present invention aims to provide a thinner and lighter burning apparatus for railway repair and cooling the combustion assembly.

Please refer to <FIG> and <FIG> together. A burning apparatus <NUM> is provided for railway repair, such as for heating the railway tracks or drying the molds during the aluminothermic welding process. Specifically, the burning apparatus <NUM> defines a longitudinal axis P and includes an air compressor assembly <NUM> and a combustion assembly <NUM>. The air compressor assembly <NUM> is used for inhaling air and forcing air (with oxygen) into the combustion assembly <NUM> of the burning apparatus <NUM>. The combustion assembly <NUM> is used for the reaction of combustion and for producing flames. The air compressor assembly <NUM> and the combustion assembly <NUM> are axially disposed along the axis P. During operation, the air compressor assembly <NUM> compresses air with oxygen into the combustion assembly <NUM>, so the combustion assembly <NUM> can ignite the fuel and oxygen and produce a flame for railway repair. The temperature of a flame may be within the range of <NUM> and <NUM> Celsius degrees for welding railways. The axial arrangement of the air compressor assembly <NUM> and the combustion assembly <NUM> makes the overall burning apparatus <NUM> thinner, smaller, and more symmetric. Thus, a welding operator can easily handle and operate the burning apparatus <NUM> at a railway construction site.

Please refer to <FIG> together. The air compressor assembly <NUM> includes an inlet opening <NUM>, an outlet opening <NUM>, a body <NUM>, a motor <NUM>, and a propeller <NUM>. The inlet opening <NUM> is used for inhaling air into the burning apparatus <NUM>, and the outlet opening <NUM> is used for communicating with the combustion assembly <NUM>. The motor <NUM> includes a motor shaft <NUM> and is disposed in the body <NUM>. The motor <NUM> drives the propeller <NUM> through the motor shaft <NUM>. The inlet opening <NUM> may be configured to be any shape for guiding air into the inlet opening <NUM> of the air compressor assembly <NUM> and therefore into the body <NUM>. The body <NUM> is axially disposed along the axis P. The body <NUM> comprises an outer housing <NUM>, an inner housing <NUM>, and an air passage <NUM>. Specifically, the inner housing <NUM> is disposed in the outer housing <NUM> and is connected to the outer housing <NUM> of the body <NUM>. The motor <NUM> is disposed in the inner housing <NUM> of the body <NUM>. The inner housing <NUM> and the outer housing <NUM> define an air passage <NUM> therebetween. The propeller <NUM> guides air from the air compressor assembly <NUM> into the combustion assembly <NUM> through the air passage <NUM>. Namely, the inlet opening <NUM>, an outlet opening <NUM>, and the air passage <NUM> allow air to flow therethrough.

To avoid the turbulence of the air in the burning apparatus <NUM>, the body <NUM> of a preferred embodiment also includes a rib <NUM> or multiple ribs <NUM> for realizing a more laminar flow motion of air in the air passage <NUM> and for reinforcing the connection between the outer housing <NUM> and the inner housing <NUM>. The ribs <NUM> may fully or partially extend between the outer housing <NUM> and the inner housing <NUM> in the air passage <NUM>.

To facilitate the compression and transmission of air into the inlet opening <NUM> of the combustion assembly <NUM>, the air compressor assembly <NUM> further comprises a hood <NUM> configured for guiding and sucking air into the inlet opening <NUM> of the air compressor assembly <NUM>. The hood <NUM> is also axially disposed along the axis P and adapted to the propeller <NUM> to collect and optimize air transmission into the burning apparatus <NUM>. In a preferred embodiment, the hood <NUM> is configured to be shaped for optimally guiding the air from the propeller <NUM> into the air passage <NUM> of the body <NUM> of the air compressor assembly <NUM>.

To strengthen the connection and assembling of the body <NUM> and the hood <NUM>, the air compressor assembly <NUM> further comprises a plastic mounting plate <NUM> and a metal mounting plate <NUM>. The plastic mounting plate <NUM> and the metal mounting plate <NUM> include openings to let air go into the air passage <NUM> of the air compressor assembly <NUM>. The plastic mounting plate <NUM> is for receiving the propeller <NUM> and disposed between the hood <NUM>, the metal mounting plate <NUM>, and the body <NUM>. The plastic mounting plate <NUM> may include a propeller guiding feature to realize a more laminar flow of the air. The metal mounting plate <NUM> is disposed between the plastic mounting plate <NUM> and the body <NUM>. Several screws <NUM> are used for the connection between the plastic mounting plate <NUM>, the metal mounting plate <NUM>, the hood <NUM>, and the body <NUM> of the air compressor assembly <NUM>, improving the stability of the air compressor assembly <NUM>. The body <NUM> of the air compressor assembly <NUM> can be constructed as integral, and the hood <NUM> and the body <NUM> can be constructed as integral. The air compressor assembly <NUM> and the combustion assembly <NUM> can be constructed as integral.

A motor of a conventional burning apparatus <NUM> usually has a problem in heat dissipation when the motor works. The burning apparatus <NUM> is designed to have a cooling feature. Specifically, the inner housing <NUM> of the body <NUM> includes an inner housing opening <NUM> which allows air to flow from the air passage <NUM> into the inner housing <NUM> for cooling the motor <NUM>. So, the air in the air compressor assembly <NUM> is fully circulated. In addition, the inner housing <NUM> also includes a cavity <NUM> for optimizing the flow path of the cooling air. Also, the body <NUM> includes a wire channel <NUM> passing through the outer housing <NUM> and the inner housing <NUM> to receive a wire of the motor <NUM> and/or to release the cooling air which also cools down the wire of motors <NUM> accordingly. The wire channel <NUM> and the cavity <NUM> are communicated.

Please refer to <FIG> together. The combustion assembly <NUM> includes a combustion assembly housing <NUM>, a fuel means <NUM>, an ignition means <NUM>, and a burning tube assembly <NUM>. The combustion assembly housing <NUM> may be configured to be a tube and is connected to the air compressor assembly <NUM>. The combustion assembly housing <NUM> also includes an inlet opening <NUM> and an outlet opening <NUM>. The inlet opening <NUM> of the combustion assembly housing <NUM> communicates with the outlet opening <NUM> of the air compressor assembly <NUM>, so air can be blown into the combustion assembly <NUM>. The fuel means <NUM> is for providing fuel into the combustion assembly <NUM>. The fuel can be any flammable fuel, gas, or liquid for combustion, such as propane, butane, or hydrogen. A fuel providing device <NUM> can be arranged for storing fuel and be connected to the fuel means <NUM> by a hose (not shown in the drawings). For example, the fuel providing device <NUM> can be a fuel tank or a gas cylinder. Similarly, the ignition means <NUM> is for igniting the fuel and is connected to an external electrical device <NUM>. For example, the external electrical device <NUM> can be an electrical generator or a power source providing a desired voltage. When the ignition means <NUM> ignites the fuel in the combustion assembly <NUM> to produce a flame F, the air compressor assembly <NUM> blows the flame F out of the outlet opening <NUM> of the combustion assembly <NUM>.

Combustion takes place in a burning tube assembly <NUM>. The burning tube assembly <NUM> is disposed in the combustion assembly housing <NUM> of the combustion assembly <NUM>, and is preferably near the lower part of the combustion assembly housing <NUM> of the combustion assembly <NUM>. Specifically, the burning tube assembly <NUM> includes a burning tube body <NUM>, an inlet disc <NUM>, and an outlet disc <NUM>. The detail of the burning tube assembly <NUM> is provided as follows.

The burning tube body <NUM> is configured to be hollow, and is disposed along the axis P and in the combustion assembly housing <NUM> and between the inlet disc <NUM> and the outlet disc <NUM>. The burning tube assembly <NUM> is preferably located near the bottom of the combustion assembly housing <NUM> of the combustion assembly <NUM>. The burning tube body <NUM> and the combustion assembly housing <NUM> define an air channel <NUM> therebetween. In a preferred embodiment, the burning tube body <NUM> further includes openings <NUM> designed along the burning tube body <NUM> to control the amount of air entering from the air channel <NUM> into the burning tube body <NUM>. The inlet disc <NUM> contains holes for receiving the fuel means <NUM> and the ignition means <NUM>. Additionally, the inlet disc <NUM> contains openings <NUM> to allow air to enter the air channel <NUM>. So, the air flowed from the air compressor assembly <NUM> into the air channel <NUM> of the combustion assembly <NUM> via the openings <NUM> of the inlet disc <NUM>. On the other hand, the outlet disc <NUM> is formed as a circular disc for sealing the bottom of the air channel <NUM>, while the outlet disc <NUM> leaves the bottom of the burning tube body <NUM> open, so a flame F ejects out of the burning apparatus <NUM>. As a result, the air passage <NUM> of the air compressor assembly <NUM>, the openings <NUM> of the inlet disc <NUM>, the air channel <NUM> of the combustion assembly <NUM>, the openings <NUM> of the burning tube body <NUM>, and the outlet opening <NUM> of the combustion assembly <NUM> are designed to be communicated for the airflow G (please see the airflow G of <FIG>).

The fuel means <NUM> and the ignition means <NUM> extend into the burning tube body <NUM> through the holes of the inlet disc <NUM>. Hence, the fuel is provided in the burning tube body <NUM>, and the combustion of the mixture of the fuel and oxygen ignited by the ignition means <NUM> happens in the burning tube body <NUM>. The fuel means <NUM> may be a fuel tube for transmitting fuel, and the ignition means <NUM> may be an ignition electrode. The fuel means <NUM> and the ignition means <NUM> may extend from the outside of the burning tube assembly <NUM> into the burning tube body <NUM> and fixed at the inlet disc <NUM>, so the fuel means <NUM> and the ignition means <NUM> can limit the reaction of the combustion in the burning tube body <NUM>. In another preferred embodiment, the fuel means <NUM> and the ignition means <NUM> may be included in the air compressor assembly <NUM>.

To further optimize the cooling effect of the burning tube assembly <NUM> and improve the efficiency of the combustion, the openings <NUM> of the burning tube body <NUM> closer to the inlet disc <NUM> may be designed to be smaller than the openings <NUM> of the burning tube body <NUM> closer to the outlet disc <NUM>. For example, the openings <NUM> of the burning tube body <NUM> can be the first set openings <NUM>, the second set openings <NUM>, and the third set openings <NUM>. The first set openings <NUM> are located near the inlet disc <NUM>; the third set openings <NUM> near the outlet disc <NUM>; the second set openings <NUM> are at somewhere between the first set openings <NUM> and the third set openings <NUM>. Namely, the first set openings <NUM> near the inlet disc <NUM> are smaller than the third set openings <NUM> near the outlet disc <NUM>. This leads to the following benefits. First, the smaller first set openings <NUM> limit the amount of air entering the first set openings <NUM> and allow more air flowing in the air channel <NUM> down to the third set openings <NUM> along the burning tube body <NUM>, so that air can cool down the burning tube body <NUM> as well as the combustion assembly housing <NUM>. Second, the size of the smaller first set openings <NUM> allows more converged air to enter the burning tube body <NUM>. This can stabilize the formation of a converged flame F in the burning tube body <NUM>. The flame F formed near the inlet disc <NUM> is preferably to be stable and converged. Third, the combustion of fuel needs merely a small amount of oxygen, so the smaller first set openings <NUM> can maintain the small amount of air and oxygen entering the burning tube assembly <NUM> to achieve the desired amount and shape of a flame. A preferred flame is slim and thin. Fourth, the bigger third set openings <NUM> at the outlet disc <NUM> help blowing the combusted flame F out of the outlet end of the burning tube assembly <NUM>. The second set opening <NUM> and the third set openings <NUM> allow more oxygen to enter the burning tube body <NUM>, ensuring a better mixing of the fuel and oxygen and pushing the flame F from the burning tube body <NUM> towards the axis P and thus towards the outlet opening <NUM>. The burning tube assembly <NUM> leads to minimal contact of the flame F with the burning tube body <NUM>, so the burning apparatus <NUM> and the combustion assembly <NUM> are cooled down during the operation of the burning apparatus <NUM>.

To ensure the safety of the combustion, the combustion assembly <NUM> includes a sensor <NUM> for monitoring and detecting the formation of flame F. Specifically, a welding operator may operate the burning apparatus <NUM> together with the sensor <NUM> with the following steps: (A) activate the air compressor assembly <NUM>, (B) activate the ignition means <NUM>, (C) provide fuel by the fuel means <NUM>, and (D) detect the presence of the flame F by the sensor <NUM>. If there is no flame detected by the sensor <NUM>, a welding operator checks or restarts the burning apparatus <NUM> to ensure the safe operation.

Claim 1:
A burning apparatus for railway repair, defining an axis (P) and comprising:
an air compressor assembly (<NUM>) including an inlet opening (<NUM>) and an outlet opening (<NUM>), and
a combustion assembly (<NUM>) connected to the outlet opening (<NUM>) of the air compressor assembly (<NUM>),
wherein the air compressor assembly (<NUM>) and the combustion assembly (<NUM>) are axially disposed along the axis (P), and wherein the air compressor assembly (<NUM>) compresses air into the combustion assembly (<NUM>),
wherein the air compressor assembly (<NUM>) further comprises:
a body (<NUM>) axially disposed along the axis (P),
a motor (<NUM>) including a motor shaft (<NUM>) and disposed in the body (<NUM>), and
a propeller (<NUM>) driven by the motor (<NUM>) through the motor shaft (<NUM>) and guiding air into the body (<NUM>),
characterised in that the body (<NUM>) comprises:
an outer housing (<NUM>), and
an inner housing (<NUM>) disposed in the outer housing (<NUM>) and connected to the outer housing (<NUM>), the motor (<NUM>) disposed therein,
wherein the inner housing (<NUM>) and the outer housing (<NUM>) defining an air passage (<NUM>) therebetween, and the propeller (<NUM>) guides air from the air compressor assembly (<NUM>) into the combustion assembly (<NUM>) through the air passage (<NUM>).