Flameless Heater System

Abstract

A flameless heater system that doubles as a source of compressed air. The flameless heater system generally includes an engine and an air compressor as sources of radiant heat. Air is forced past an engine radiator and an air compressor heat exchanger to create heated forced air that is conducted through ducts to a desired destination. The system can be operated only as a heater, or only as a source of compressed air, or both at the same time.

Description

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable to this application.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a flameless heater and more specifically it relates to a flameless heater system that can double as a system for producing compressed air. Radiant heat from an engine that drives an air compressor, and from the air compressor, is used to heat forced air that is ducted to a desired location.

2. Description of the Related Art

Any discussion of the related art throughout the specification should in no way be considered as an admission that such related art is widely known or forms part of common general knowledge in the field.

Industrial-sized heaters are used to heat large volumes of enclosed air, such as an enclosed space in a building in which construction is underway, or a manufacturing facility, or some other type of work site. In general, the heating elements are exposed directly to ambient air, which is heated by the heating elements and moved around by the fan. Many heating elements, such as a flame produced by burning hydrocarbon fuel, are routinely exposed to ambient air, at a temperature far above the ignition point of hydrocarbon and other flammable gasses. Unfortunately, there is often a danger that such flammable gasses may be found at such work sites. For example, a liquid fuel such as gasoline may leak through a hole in a tank or pipe and evaporate, creating flammable fumes at the work site. In such a case, the fumes may be exposed to the flame-based heating element and catch fire, or even explode.

In addition, large air compressors are often used at work sites, for example to power pneumatic tools. The air compressors are generally driven by engines, and the engines are generally cooled using a radiator. Further, the air compressors generally produce heat adiabatically as the air is compressed and such air compressors are suitable for usage in various embodiments of the present invention. The heat from the engine and from the air compressor is generally dissipated as waste heat.

Because of the inherent danger and waste associated with the related art, there is a need for a safer, more efficient way to produce heat and compressed air on an industrial scale.

BRIEF SUMMARY OF THE INVENTION

Described herein is an industrial scale heater which does not use a flame or other heat source as a heating element that is exposed to ambient air. The heater is integrated with an air compressor driven by an engine as a system. The heat produced by the engine and the air compressor is captured and used as the flameless heater's heat source. In embodiments, the system includes sensors that sense aspects of the system and generate sensor signals, a user interface with input devices for a user to input settings and output devices to convey the state of aspects of the system, control elements that control aspects of the system in accordance with control signals, and a controller that receives the user settings and monitors the sensor signals, and automatically generates the control signals to control the control elements based on the sensor signals and the user settings.

There has thus been outlined, rather broadly, some of the features of the invention in order that the detailed description thereof may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and that will form the subject matter of the claims appended hereto. In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction or to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of the description and should not be regarded as limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

Various other objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:

FIG. 1A is a perspective view of the outside of a flameless heater system embodiment mounted on a trailer.

FIG. 1B is a perspective view of the outside of the flameless heater system of FIG. 1A installed at a work site.

FIG. 2 is a perspective view of the system of FIG. 1A with the cover removed.

FIG. 3 is a top view of the system of FIG. 1A with the cover removed.

FIG. 4 is a bottom view of the system of FIG. 1A mounted on a trailer.

FIG. 5 shows a layout of an embodiment of the system in which the fan is pneumatically powered.

FIG. 6 is a diagram illustrating components of the system of FIG. 5 whose state is sensed by sensors that send sensor signals to the controller, and components whose operation is controlled by control signals from the controller.

FIG. 7 is a layout of an embodiment of the system in which the fan is hydraulically powered.

FIG. 8 is a diagram illustrating components of the system of FIG. 7 whose state is sensed by sensors that send sensor signals to the controller, and components whose operation is controlled by control signals from the controller.

FIG. 9 is an illustration of an exemplary embodiment of a user interface.

FIG. 10 shows flow diagrams of an exemplary system startup procedure and an exemplary system shutdown procedure.

FIG. 11 is a diagram illustrating an exemplary fluid system suitable for use with a rotary screw compressor that utilizes oil to lubricate and seal the compression screws.

DETAILED DESCRIPTION OF THE INVENTION

Any and all headings appearing in this disclosure are used for convenience only and have no limiting effect. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety to the extent allowed by applicable law and regulations.

Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views, FIGS. 1A through 10 illustrate example embodiments of a flameless heater system. The system comprises heat sources that generate heat while producing compressed air, for example to power pneumatic tools, such as an air compressor and the engine that drives it. In the past, this heat has been vented as waste heat. In contrast, the disclosed system does not discard the heat, but uses it to heat air that is then conducted to provide heat to a desired location. Moreover, unlike open flame heat sources, the heat sources used in the disclosed system only present surfaces open to ambient air that remain below the ignition temperature of flammable fumes that might be present at a work site.

FIG. 1A is a perspective view of the outside of a flameless heater system embodiment mounted on a trailer, showing an enclosure containing the heat sources and other system elements mounted on a trailer. Alternatively, the system can be mounted on a skid or the like, or can be installed permanently at a work site. As shown, the trailer has a solid surface that supports the system frame 1a at its base, and wheels 1b and hitch 1c for towing the system to/from a work site. The system comprises an enclosure housing 1 that contains the engine and air compressor. In an embodiment, the front of the housing E may be curved to reduce drag due to air friction as the trailer is being towed. Also shown are ambient air side intake vents 2 and heated air outlet 2a. In an embodiment, the interior of the enclosure can be accessed through side access doors 1h. In an embodiment, there may be disposed behind the doors a control surface or the like. The control surface may have mounted thereon user input devices for inputting settings to adapt the system to operate in a preferred manner or for use in a particular situation, or user output devices for displaying the state of various aspects of the system, or both.

FIG. 1B is a perspective view of the outside of the flameless heater system of FIG. 1A installed at a work site, and shows the trailer with heating system parked at a work site for operation. The installation includes coupling heated air ducts 26 to the hot-air outlet through a cover plate 1g. The cover plate may be bolted as shown to completely cover the edge of the hot-air outlet, and may be made airtight with a gasket or the like. The cover plate may also have flanges to which the hot air ducts 26 may be removably coupled. The ducts may be flexible for ease of installation to conduct the heated air to a desired location.

FIG. 2 is a perspective view, and FIG. 3 is a top view, of the system of FIG. 1A with the enclosure housing removed. As shown, the system comprises engine 3 which generates heat by burning fuel within the engine block, and is cooled by transferring heat to a liquid coolant that is pumped through the block. The cooling fluid then passes through radiator 4 where heat is transferred from the coolant to the radiator, and the cooled coolant returns to the engine to be heated again. In an embodiment, the radiator is placed apart from the engine and oriented to enhance heat transfer to the forced air stream.

The burning fuel in the engine produces hot exhaust gasses that flow through exhaust pipe 16 to engine exhaust heat exchanger 10. The hot exhaust gasses transfer heat in the heat exchanger to air that is forced through it. In an embodiment, the exhaust pipe passes from one side of a divider wall 12 to the other side, for example through a hole in the divider wall as shown.

The engine generates motive force that is operatively coupled to air compressor 5, and drives it to compress air. The air heats as it is compressed (e.g. adiabatically), and heat is transferred from the hot compressed air/oil mixture to coolant forced through a compressor heat exchanger 9 (shown as an oil heat exchanger in FIG. 11 where an oil/air separator tank is used). In an embodiment, the hot compressed air flows directly through a heat exchanger, for example through tubes. In another embodiment, liquid coolant is pumped via a separate pathway through the hot compressed air to move heat from the compressed air to the heat exchanger, where the coolant transfers the heat to air forced through the heat exchanger. In this embodiment, the compressed air coolant circulates through the hot compressed air and the heat exchanger in a cycle similar to the engine coolant flowing through the engine and the radiator previously described.

Changing the temperature and pressure, within the system, of air that contains some water vapor as humidity may cause the water vapor to condense into water. The water may then be separated from the air in air/water separator 25 positioned inline of the pressurized air, and conveyed out of the enclosure in any convenient manner known in the art.

FIG. 4 is a bottom view of the system of FIG. 1A. In this embodiment, the underside of the enclosure front portion 1e comprises lower intake vents 2. Ambient air is drawn into the enclosure through the side and lower intake vents by a fan inside the enclosure. The fan then forces the drawn air through the enclosure. The forced air is heated as it is forced past or through the engine radiator, the engine exhaust heat exchanger, and the compressor heat exchanger, all disposed inside the enclosure. In an embodiment, one or more grills may be disposed near the vents to direct the air as it is drawn into the enclosure, and one or more baffles may be placed within the enclosure to direct the air as it passes through the enclosure. The grill and baffle elements are arranged to enhance the transfer of heat to the forced air as it passes through the heat transfer elements. The heated forced air is then forced through the air ducts as a working fluid, to convey its heat to the remote end of the air ducts. The remote end of the ducts can be placed so that the heated forced air heats an enclosed work space such as a warehouse or other building, or can be ducted to a specific location to heat that location and any objects and people nearby.

FIG. 5 shows a layout of an embodiment of the flameless heater system in which the fan 24 is powered by an air motor 21. The air motor is powered pneumatically by compressed air from the air compressor 5 which obtains unpressurized air though air filter 6. The air motor 21 obtains compressed air via main air line 35. The figure also shows engine 3 and its radiator 4, and engine coolant lines 7, 8. Engine coolant is heated as it flows through the engine, and the heated coolant is conveyed through one of the engine coolant lines to the radiator, where it is cooled. Then the cooled coolant flows through the other coolant line back to the engine where it is heated again, defining a fluid circuit. The coolant flows continuously through this fluid circuit. The engine generates motive power by internal combustion of fuel. The fuel is obtained from the fuel tank 30 through the fuel filter 36. A

The air compressor 5 may be comprised of any type of air compressor (or gas compressor) that is adapted for compressing a gas whereby the compression of the gas generates heat. One type of suitable air compressor is a positive-displacement compressor which includes rotary compressors (e.g. lobe, rotary screw compressor, rotary screw blower, liquid ring, scroll, vane) or reciprocating compressors (e.g. piston-type compressor). Dynamic compressors may be used such as centrifugal compressors or axial-flow compressors. One or more air compressors may be mechanically connected to the engine. A rotary screw compressor is a type of gas compressor that uses a rotary type positive displacement mechanism. The rotary screw compressor is comprised of a pair of rotary screws that provide a gas compression process in a continuous sweeping motion so there is little pulsation or surging of flow which occurs with piston compressors.

The air compressor 5 draws in air through the air filter 6 and compresses it, which heats the compressed air adiabatically. The compressed air is fed into main air line 35, and is conveyed by the line to one or more loads such as pneumatic tools (not shown), in addition to the air motor that drives the fan. The hot compressed coolant is cooled in heat exchanger 9. The air compressor and the heat exchanger, together with air compressor coolant lines 14, 15, define a fluid circuit through which a fluid coolant flows. The fluid coolant may be the compressed gas itself passing it through heat exchanger 9, or the coolant may be a liquid coolant that is heated by the hot compressed air and cooled in the heat exchanger 9. The water separator 25 draws condensed water out of the main air line.

The engine exhaust pipe 16 receives hot exhaust gasses from the engine and conveys the hot gasses through exhaust heat exchanger 10, and from there through exhaust pipe outlet 17 where it leaves the system.

In addition, FIG. 5 shows structural elements such as the frame/enclosure housing 1 and the divider wall 12. Areas within the enclosure are defined by the wall, including engine compartment 18 and fan compartment 29.

FIG. 5 also shows, and FIG. 6 shows with greater clarity, a plurality of sensors that sense the state of various aspects of the system, and a plurality of control devices that control various aspects of the system. Controller 19 receives the sensor signals and, based on the sensor signals, generates control signals that it sends to the control devices. In the illustrated example embodiment, the sensors include fan speed sensor 32, temperature sensor 33 that senses the temperature of the forced heated air leaving the heated air outlet, and temperature sensor 34 that senses the temperature of the hot compressed coolant or air/oil mixture leaving the compressor. In the illustrated example embodiment, the control devices include flow regulator 11 that regulates the discharge air stream from the fan motor, and pressure/flow regulator 23 that regulates the flow and/or pressure of compressed air to pneumatic loads 22, 37 (represented by the dotted boxes), pressure regulators 52 that regulates the air pressure in the main air line, and the flow regulator 11 that regulates the discharge air stream.

In embodiments, the radiator 4 may be remote mounted relative to the engine 3 to provide the maximum heat transfer. The air compressor 5 may be either directly or indirectly coupled to the engine. Compressed air from the air compressor may be directed to a manifold monitored by a pressure gauge 31, and controlled with a pressure regulator 52. The compressed air may be distributed as desired to a silencer 13, optional multi-purpose load control 22, and/or directly to the fan motor 21 to supply power to run the fan, all controlled by controller 19, as will be described. Air from the silencer 13 is preferably exhausted on the fan side of divider wall 12. The heat exchangers 9, 10 are preferably placed on the engine side of the divider wall, to enhance heat transfer to the forced air stream. Ducting may be arranged from the fan to connect forced heated air to the heated air outlet 2a, where it will then be conducted to the desired location via flexible ducting. The fan motor 21 can be directly mounted to the fan 24 via a shaft. Controller 19 is communicatively connected to the various components/sensors to continually monitor system performance to ensure the user input operating conditions are met, and also safely shut down the system in the event of adverse or dangerous conditions. The controller receives its inputs from at least some of the following: engine 3, air compressor 5, temperature sensor 34, flow regulator 11, speed sensor 32, outlet air temperature sensor 33, pressure/flow regulator 23, pressure gauge 31, pressure regulators 52, and fuel tank 30. The controller uses information from these inputs to generate and send control outputs to at least some of the following components: engine 3, air compressor 5, flow regulator 11, pressure regulators 52, pressure flow regulator 23, and operation beacon 38.

In an example embodiment, one or more user input devices (shown in FIG. 9 for example) can be used to input settings that influence the operation of the system, for example, by setting a desired heated air temperature to be maintained at the heated air output. The user input devices can be assembled in a control panel that may be accessible through side access doors 1h. Such a control panel may also comprise one or more user output devices (again shown in FIG. 8) to indicate to a user the current state of various aspects of the system. In the example embodiment illustrated in FIG. 5, the output devices (i.e., status indicators) include a pressure gauge 31 that shows the pressure of the compressed air output by the system to external pneumatic loads. The operating beacon 38 which is on when the system is operating can also be considered an output device. In an embodiment, controller 19 generates control signals to the control devices based on the sensor signals in conjunction with the user input settings.

FIG. 7 shows a layout of an embodiment of the flameless heater system in which fan 24 is powered by hydraulic motor 42. FIG. 7 shows, and FIG. 8 shows with greater clarity, a plurality of sensors that sense the state of various aspects of the system, and a plurality of control devices that control various aspects of the system. As before, controller 19 receives the sensor signals and, based on the sensor signals, generates control signals that it sends to the control devices. The differences between FIGS. 5, 6 and FIGS. 7, 8 consist essentially of removing elements of the pneumatic system related to powering the air motor and corresponding sensors and control devices, and adding elements related to the hydraulic system that powers the hydraulic motor and corresponding sensors and control devices. Otherwise, the embodiment illustrated in FIGS. 5, 6 is very similar to the embodiment shown in FIGS. 7, 8.

In FIG. 7, the hydraulic motor is powered by hydraulic pump 39, which itself is powered by the engine. The hydraulic pump pumps oil through proportional valve 40 to the motor, then back to the pump, in a path that defines hydraulic circuit 41. The oil in the circuit is cooled by hydraulic circuit cooler 43 and filtered by hydraulic circuit filter 44. The circuit also includes hydraulic reservoir 45, which provides elasticity to the circuit and prevents noisy operation due to hydraulic component vibration.

In yet another embodiment (not shown), the fan may be powered by an electric motor. In this embodiment, none of the components pertaining to providing, monitoring, and controlling either the pneumatic power system or the hydraulic power system are necessary.

In an embodiment using a hydraulic fan motor, the controller collects inputs from at least some of the following components; engine 3, pressurized air source 5, temperature sensor 34, flow control valve 46, speed sensor 32, outlet air temperature sensor 33, hydraulic temp switch 48, hydraulic level switch 49, hydraulic system regulator 40, flow regulator 37, and fuel tank 30. The controller 19 sends outputs to the following components: engine 3, pressurized air source 5, flow control valve 46, hydraulic system regulator 40, flow regulator 37, and operation beacon 38.

FIG. 9 illustrates an exemplary user interface 60 comprising user input devices and user output devices. The user input devices include on/off button 61, a fan button 62 that sets fan speed to a desired value, increase/decrease buttons 63, 64 used to set the desired output temperature in an econo mode; a mode selector 65 that enables the user to select a desired mode of operation; and a mode selector 69 that sets the mode of operation. The user output devices include temperature display 66 that shows the temperature of a predetermined system element, tachometer 67 that shows the speed of the fan, load indicator 68 that shows the load on the engine as a percent of its rated power; and an indicator 70 pertaining to the speed of the fan. It is to be understood that many other user interface configurations are possible, for example a configuration that includes a fuel level gauge.

The system consists of a mobile unit that is used to transfer energy in the form of heat from the unit to a remote area outside of the unit. The unit consists of 2 main systems: the chassis and pneumatic heat system. The chassis consists of a structural outer frame and containment box 1 that can be skid mounted or connected to a trailer with wheels for transportation behind a vehicle. The chassis also acts as an enclosure to prevent heat from escaping to the outside ambient air. In addition, it will direct the airflow in a manner that will ensure maximum heat capture.

The pneumatic heat system consists of the engine 3 loaded by a pressurized air source(s) 5 where the heat rejected from both components is converted into forced air heat. An engine radiator 4, engine exhaust heat exchanger 10, pressurized air source heat exchanger(s) 9, and hydraulic circuit cooler 43 will capture this energy. A fan 24 and fan motor(s) 21, 42 controlled by pressure/flow regulators 11, 52 if powered with pressurized air or proportional valve 40 if powered by hydraulic fluid will move the air necessary to transfer this heat. The intake grill 2 directs airflow through the machine and across heat exchangers and through the air outlet 26. The fan motor(s) 21, 42 will be driven by the compressed air from the pressurized air source 5 or fluid from the hydraulic pump 39.

The radiator 2 may be remotely mounted relative to the engine 3 to provide the maximum heat transfer. The pressurized air source 5 will be either directly or indirectly mounted to the engine 3. Air flow from the pressurized air source(s) 5 will be directed to a manifold 35, which will be monitored by a pressure gauge 31 and controlled with a pressure regulator 52 in turn distribute the desired amounts of air to either a silencer 13, optional multi-purpose load control 22 or directly to the fan motor(s) 21 to supply power to run the fan(s) 24 and all controlled by the controller 19. The air from the silencer 13 will be exhausted on the fan side. The heat ex-changers 9, 10 will be placed on the engine side of the divider wall to capture as much heat transfer as possible. Ducting 10 will come off of the fan(s) 9 and connect to the outside wall of the heater, where it will then further direct air to the desired location via flexible ducting. The fan motor(s) 21 will be directly mounted to the fan(s) 24 via a shaft. The controller 19 will be connected to the various components/sensors to continually monitor performance to ensure user defined operating conditions are met, and safely shut down the unit in the event of adverse conditions in any area. The controller 19 will collect inputs from the following components; engine 3, pressurized air source 5, temperature sensor 34, flow regulator 11, speed sensor 32, outlet air temperature sensor 33, pressure/flow regulator 23, pressure gauge 31, pressure regulators 52 and fuel tank 30. The controller 19 sends outputs to the following components: engine 3, pressurized air source 5, flow regulator 11, pressure regulators 52, pressure flow regulator 23, and operation beacon 38.

The radiator 2 will be remote mounted relative to the engine 3 to provide the maximum heat transfer. The pressurized air source 5 will be either directly or indirectly mounted to the engine 3. Air flow from the pressurized air source(s) 5 will be directed to a flow control valve 46, which will be monitored by a pressure gauge 34. Air can be returned to the inlet of the compressor or sent to the main air line 35. Air sent to the main air line 35 can pass through a water separator 25 and to a pressure regulator 52 and routed to a silencer 13 for dissipation or to the air manifold 51 to distribute air to any optional loads or all controlled by the controller 19. The heat ex-changers 9, 10 will be placed on the engine side of the divider wall to capture as much heat transfer as possible. Heat duct outlet 26 directs airflow from the fan 24 and connect to the outside wall of the heater, where it direct air to the desired location via flexible ducting. The hydraulic fan motor(s) 42 will be directly mounted to the fan(s) 24 via a shaft. The controller 19 will be connected to the various components/sensors to continually monitor performance to ensure user defined operating conditions are met, and safely shut down the unit in the event of adverse conditions in any area. The controller 19 will collect inputs from the following components; engine 3, pressurized air source 5, temperature sensor 34, flow control valve 46, speed sensor 32, outlet air temperature sensor 33, hydraulic temp switch 48, hydraulic level switch 49, hydraulic system regulator 40, flow regulator 37, and fuel tank 30. The controller 19 sends outputs to the following components: engine 3, pressurized air source 5, flow control valve 46, hydraulic system regulator 40, flow regulator 37, and operation beacon 38.

A design will utilize a controller 19 and display, with software. The controller 19 will utilize user inputs via the display to control the engine 3, pressurized air source(s) 5, fan motor(s) 21 and pressure sensor 31 on the main air line 35.

The pressurized air source(s) 5 will either be directly or indirectly coupled to the engine crank shaft. Indirect coupling can include, but not be limited to, a gearbox/transmission and/or pulley system to operate the pressurized air source(s) 5 at the desired revolutions per minute if different than engine revolutions per minute. The pressurized air source(s) 5 will be loaded and unloaded via the inlet valve or by regulating system pressure on the pressurized air source(s) 5.

General machine function is as follows. Beginning with machine powered off—the user will push a functional start button to begin the glow plug cycle and engine starting. The pressurized air source(s) 5, fan motor(s) 21 and any auxiliary air tank(s) (not shown) will be in a no/minimum load state, as commanded by the controller 19. Once the engine coolant temperature is measured at a specified level, the engine 3 will be loaded by the pressurized air source(s) 5 via the controller 19. The controller 19 will receive input from pressure gauges 31, and begin to load the engine 3 with the pressurized air source(s) 5 via the air inlet control or system pressure on the pressurized air source(s) 5. At this time the fan will be set at the desired speed defined by user input. For normal shutdown, a user input will tell the controller 19 to gradually unload the engine 3, reduce engine revolutions per minute and allow a proprietary shut down sequence to occur.

The flameless heater will utilize several energy sources including the engine coolant package, the engine heat rejection to ambient (from block, heads, exhaust system), the heat exchanger for compressed air (air to air or air to liquid), the heat exchanger for pressurized air source cooling (liquid to air or air to air), and/or the pressurized air source heat rejection to ambient exhaust system heat exchanger.

The controller 19 will adjust the pressurized air source(s) 5 loading based on used inputs and temperature sending unit inputs. Additionally, the controller 19 will turn on/off external signaling devices (not shown) to visually indicate machine function. Other potential inputs for the controller 19 that aren't listed above are but not limited to:

1. Emergency stop

2. Auxiliary compressed air tank(s) pressure

3. Ambient temperature

4. Pneumatic control coil feedback

5. Exhaust air temperature (for air to air/air to liquid heat exchanger)

6. Engine auto stop (for runaway diesel engine prevention)

7. Telematics communication (asset management, control, indication, etc.)

The unit will also consist of a water separator 25 to remove water out of the compressed air system to help eliminate corrosion issues and prolong system life. The water will be dissipated to the environment as water vapor discharged through the engine exhaust system to prevent ice build-up during operation in a cold environment.

A design will utilize a controller 19 and display, with software. The controller 19 will utilize user inputs via the display to control the engine 3, pressurized air source(s) 5, flow regulator 37, and hydraulic fan motor(s) 42 via the hydraulic system regulator 40.

The pressurized air source(s) 5 will either be directly or indirectly coupled to the engine crank shaft. Indirect coupling can include, but not be limited to, a gearbox/transmission and/or pulley system to operate the pressurized air source(s) 5 at the desired revolutions per minute if different than engine revolutions per minute. The pressurized air source(s) 5 will be loaded and unloaded via the inlet valve on the pressurized air source(s) 5.

General machine function is as follows. Beginning with machine powered off—the user will push a functional start button to begin the glow plug cycle and engine starting. The pressurized air source(s) 5, hydraulic pump 39 and any auxiliary air tank(s) (not shown) will be in a no/minimum load state, as commanded by the controller 19. Once the engine coolant temperature is measured at a specified level, the engine 3 will be loaded by the pressurized air source(s) 5 via the controller 19. The controller 19 will receive input from the flow control valve 46, and begin to load the engine 3 with the pressurized air source(s) 5 via the air inlet control on the pressurized air source(s) 5. Once a desired system air temperature is reached at the exit duct measured by the temperature sensor 33, the controller 19 will turn on the fan motor(s) 42 to the user defined revolutions per minute by adjusting the hydraulic system regulator 40. If compressed air is desired from by the user and input into the controller 19, the controller 19 will adjust the flow control valve 46 and direct air flow through the main air line 35 and to the flow regulator 37 to any desired load. The controller 19 may also send unused air flow through a silencer 13 if the software settings determine the air is unneeded. For normal shutdown, a user input will tell the controller 19 to gradually unload the engine 3, reduce engine revolutions per minute and allow a proprietary shut down sequence to occur. The flameless heater will utilize several energy sources including the engine coolant package, the engine heat rejection to ambient (from block, heads, exhaust system), the heat exchanger for compressed air (air to air or air to liquid), the heat exchanger for pressurized air source cooling (liquid to air or air to air), the pressurized air source heat rejection to ambient exhaust system heat exchanger, and/or the heat exchanger for hydraulic fan circuit.

The controller 19 will adjust the pressurized air source(s) 5 loading based on used inputs and temperature sending unit inputs. Additionally, the controller 19 will turn on/off external signaling devices (not shown) to visually indicate machine function. Other potential inputs for the controller 19 that aren't listed above are but not limited to:

1. Emergency stop

2. Auxiliary compressed air tank(s) pressure

3. Ambient temperature

4. Pneumatic control coil feedback

5. Exhaust air temperature (for air to air/air to liquid heat exchanger)

6. Engine auto stop (for runaway diesel engine prevention)

7. Telematics communication (asset management, control, indication, etc.)

8. Remote thermostat

The unit will also consist of a water separation system 25 to remove water out of the compressed air system to help eliminate corrosion issues and prolong system life.

One of many unique features of the present invention are that it can be configured to use the working fluid of the heat source to help deliver the heat to its desired location without using excess engine horsepower. In addition, the working fluid can be used to power tools or other equipment that uses compressed air as its energy source. The product can be used as a stand-alone compressor, a stand-alone heater, or both a heater and a compressor simultaneously. Thus the product can have year round utilization unlike other heaters on the market.

The invention will be manufactured by welding together a frame that may be mounted to a trailer for transportation purposes, or left alone to be used as a skid unit. This frame will support all of the components necessary for the unit to operate. Components will be either purchased or made internally and then placed into the frame in their desired locations/configurations. Once the unit is assembled it will be tested to ensure proper functioning before delivery to the customer.

FIG. 10 shows flow diagrams illustrating procedures for startup and shutdown of an exemplary flameless heater system, in which the startup procedure is shown across the top of the figure, and the shutdown procedure is shown across the bottom.

The startup procedure begins when a user pushes a start button 71 while the system is off, and the user inputs desired temperature output settings 72. The controller monitors the engine coolant temperature, and starts the system when the temperature reaches a predetermined threshold 73. Thereafter, depending on what mode the system is in, the controller adjusts the fan speed and system settings to achieve the desired temperature output 74. Once achieved, the controller monitors the system to maintain the state of the system 75.

FIG. 11 provides an exemplary illustration of one embodiment of the air compressor 5 that utilizes a rotary positive displacement compressor such as a rotary screw compressor. After the engine 3 is started, the engine 3 both generates heat and mechanically powers the air compressor 5 wherein the air compressor 5 generates heat. As the air compressor 5 is powered by the engine 3, the air compressor 5 draws in air through an air filter. The air compressor 5 compresses the ambient air thereby generating pressurized air and correspondingly heat. Oil that is used within the rotary screw compressor mixes with the heated air to remove a portion of the heat from the heated air and also a portion of the heat due to friction of the mechanical components in the air compressor. The air/oil mixture (heated) is then forced out from the air compressor 5 to an oil/air separator tank that separates the compressed air from the oil. The separated compressed air exits the oil/air separator tank and may pass through a compressed air heat exchanger to transfer heat from the compressed air to the air flowing through the flameless heater and then the compressed air may be discharged to the atmosphere or used in a tool requiring pressurized air. The separated oil flows from the oil/air separator tank to a thermal valve which directs the separated oil back to the air compressor 5 if the oil temperature is below a desired minimum temperature level for heating as shown in FIG. 11. As further shown in FIG. 11, if the separated oil exceeds a desired minimum temperature level then the separated oil is directed by the thermal valve to an oil filter for cleaning and then onto the oil heat exchanger. The oil heat exchanger transfers the heat from the separated oil to the air flowing through the flameless heater system thereby further increasing the temperature of the air flowing through the enclosure and to the heated air outlet 2a. The cooled oil from the oil heat exchanger then returns to the air compressor to repeat the process again wherein the returned oil is combined with the compressed air to form the air/oil mixture (heated) as shown in FIG. 11. Depending upon the size and type of air compressor used, the flowrate of oil into and out of the air compressor 5 may reach levels of 13-19 gallons per minute (or greater or lower).

The air drawn into the enclosure is heated by one or more heat devices comprising the engine radiator 4, the engine 3, the air compressor 5, the compressor heat exchanger (oil heat exchanger) 9, the engine exhaust heat exchanger 10, and/or the compressed air heat exchanger (see FIG. 11) in any combination and in any order thereof. The heated air is then discharged out through the heated air outlet 2a for use in heating an area.

In an exemplary embodiment of operation of the flameless heater system, ambient air is drawn into the intake vents 2 (sides and bottom of the front nose of trailer enclosure) by the fan 24 (e.g. air powered fan, hydraulic powered fan, electric powered fan) that is drawn or forced through the enclosure. In the exemplary embodiment, the forced air passes through the radiator 4 and is heated to a first temperature. The forced air passes directly over the engine and the air compressor 5 to be heated to a second temperature that is higher than the first temperature. The forced air then passes through the compressor heat exchanger 9 (also referred to as the oil heat exchanger in FIG. 11) which to be heated to a third temperature that is higher than the second temperature. The forced air then passes through a compressed air heat exchanger (no illustrated in FIGS. 5, 7) to be heated to a fourth temperature that is higher than the third temperature. The compressed air heat exchanger may be positioned between the compressor heat exchanger and exhaust heat exchanger. The forced air then passes through the engine exhaust heat exchanger 10 to be heated to a fifth temperature that is higher than the fourth temperature. The forced air then is heated to the desired temperature and is forced out through the heated air outlet 2a through one or more heat ducts 26 to be used in heating a room, building or providing heated air to workers working outdoors. The heat exchangers may be positioned in various locations within the structure/enclosure in a manner to achieve the maximum level of heat transfer to the air passing through the structure/enclosure. It is further preferable, though not required, that the heat exchangers are positioned along a common pathway one behind another and/or are parallel to one another as illustrated in FIGS. 5 and 7.

The shutdown procedure begins when a user pushes the start/stop button 76 while the system is on. Alternatively, the user interface may comprise separate startup and shutdown buttons. In either case when the button is pushed, the system is unloaded and the engine revolutions per minute is reduced 77. After the system is unloaded, an embodiment-specific shutdown sequence is followed 78, in order to protect system components and ending. When the sequence is completed, the system shuts off 79.

The flameless heater system may have various modes of operation such as:

• • Econo Mode: The flameless heater is set by the user to the desired air output temperature to help conserve fuel and maintain a certain temperature. The controller will keep the air output temperature at this temperature and fan speed setting by regulating the system. This can be done by either regulating the load on the engine, the RPM' s of the engine, or the fan speed itself.
  • Max Heat Mode: The is where the user will be able to choose the desired fan speed but the controller will regulate the unit to produce the maximum amount of heat/fuel burn. The output air temperature will be whatever the unit is able to obtain with the ambient conditions at the time and the selected fan speed.
  • Compressor mode: This is where the unit will operate as a standalone compressor (i.e. not as a flameless heater). This will primarily be used in the “non-heat season” for year round utilization but could also be used during the heat season if there is no desire to capture the heat that is generated.

Various other modes may be used with the flameless heater system.

Below is a listing of reference symbols and numerals to assist the reader of this patent document. All terms in this patent application are to be given their ordinary meaning and the below glossary is not intended by the applicant to be their own lexicographer. Below is a glossary summarizing the features at least one embodiment of the flameless heater system:

1 a—Frame Base.

1 b—Trailer Wheels.

1 c—Trailer Hitch.

1 e—Enclosure Front Portion.

1 g—Heated Air Outlet Cover Plate.

1 h—Side Access Doors.

1—Outer Frame and Containment Box: This is the main frame for the machine to which all of the components attach.

2—Intake Vent: The inlet into which ambient air is drawn to absorb energy from the heat sources and to be blown out as heated forced air.

2 a—Heated Air Outlet: The outlet from which heated forced heated air is blown out.

3—Engine: The primary heat source for the flameless heater and power source to drive the air compressor and hydraulic pump.

4—Engine Radiator: A heat exchanger that heats forced air with heat from the engine.

5—Air Compressor/Blower: Compresses air using motive power from the engine. The heat generated by the compression of air is used to heat forced air in a heat exchanger, and the compressed air may be used to drive a fan motor and/or other air powered tools/equipment. The compressed air can also be run through an additional heat exchanger to capture its heat if desired.

6—Air Filters: Removes particulates from the air coming into the air compressor.

7—Engine Coolant Line One: Transports hot coolant from the engine to the radiator.

8—Engine Coolant Line Two: Transports cooled coolant from the radiator to the engine.

9—Compressor Heat Exchanger: Transfers heat from the hot compressed air/oil to the forced air stream.

10—Engine Exhaust Heat Exchanger: Transfers heat from the engine exhaust to the forced air stream.

11—Flow Regulator: Regulates the flow coming out of the air motor.

12—Divider Wall: Acts as a sealed and insulated barrier between the engine compartment and fan compartment of the flameless heater. It ensures that all air flow is directed across the heat exchangers for maximum heat capture efficiency.

13—Resonator/Silencer (i.e., muffler): Reduces the noise level of the discharge air.

14—Air Compressor Cooler Line One: Transports coolant (e.g., oil) from the hot compressed air to the air compressor heat exchanger.

15—Air Compressor Cooler Line Two: Transports cooled coolant from the compressor heat exchanger back to the air compressor.

16—Engine Exhaust Pipe: Transports exhaust from the engine to the exhaust heat exchanger.

17—Exhaust Outlet Pipe: Transports exhaust from the exhaust heat exchanger to the outside environment.

18—Engine Compartment: The “engine side” of the flameless heater containing the engine, air compressor, and associated components.

19—Controller: Generates control signals for control devices based on sensor data and user input settings. Utilizes sensor and user inputs to control the engine, compressor, fan speed, and custom manifold.

20—Storage Compartment: Storage area for duct hoses, tools, and miscellaneous pieces.

21—Compressed Air Motor: Powers the fan using compressed air from the compressor.

22—Optional Multi-Purpose Load Control: Optional loads that will make use of compressed air not used by the air motor 21.

23—Pressure/Flow Regulator: Regulates pressure/flow of air not used by the air motor 21, e.g., to compressed air tank or pneumatic tools.

24—Fan: Draws ambient air into the enclosure and forces the air across the radiator and heat exchangers and to the desired location.

25—Water Separator: Eliminates moisture that condenses in the components in the flameless heater enclosure.

26—Heat Duct: Rigid ducting may be provided from the exit of the fan to the exit of the flameless heater; and flexible or rigid ducting to conduct the heated forced air to the desired location once it leaves the unit.

27—Air Intake Stream: Incoming air into the system.

28—Outlet Air Stream: Forced heated air exiting the system.

29—Fan Compartment: The “fan side” of the flameless heating system containing the fan 24, exhaust heat exchanger 10, and air motor 21 or hydraulic motor 42.

30—Fuel Tank: Contains diesel or other fuel to run the engine.

31—Pressure Gauge: Monitors the outlet pressure of the air compressor 5.

32—Speed Sensor: Senses the fan speed and sends it to the controller 19.

33—Temperature Sensor: Senses outlet air stream temperature 28.

34—Temperature Sensor: Senses compressed air/oil mixture temperature.

35—Main Air Line: Line containing compressed air exiting the air compressor 5.

36—Fuel Filter: Filters diesel fuel to be burned by the engine.

37—Optional Pressure/Flow Regulators and Additional Loads: Additional equipment that can be added to use compressed air as a pneumatic energy source.

38—Operation Beacon: A light mounted to top of machine so the user can see the status from a distance. Green light for ok, yellow for check machine, and red for machine down, for example.

39—Hydraulic Pump: Pump powered by the engine to drive the fan 42.

40—Proportional Valve: Controls hydraulic system and fan speed based on user input from controller 19 and speed sensor 32.

41—Hydraulic Circuit: Transports oil from hydraulic pump and to the fan and back.

42—Hydraulic Fan Motor: Powers the fan using fluid from the hydraulic pump 39.

43—Hydraulic Circuit Cooler: Heats the forced air stream with hydraulic circuit heat.

44—Hydraulic Circuit Filter: Cleans oil in hydraulic circuit.

45—Hydraulic Reservoir: Stores and releases fluid as the hydraulic system works.

46—Flow Control Valve: Controls the release of compressed air to the main air line.

47—Compressor Return Line: Returns compressed air to the inlet of the air compressor when compressed air is not released into main air line 35.

48—Hydraulic Temperature Switch: Signals system shut down if hydraulic fluid temperature exceeds a predetermined threshold.

49—Hydraulic Level Switch: Signals system shut down if hydraulic fluid level is too low.

50—Emergency Stop Switch: Allows user to stop machine instantly in emergency situations.

51—Compressed Air Outlet: Outlet where pneumatic tools can be connected.

52—Pressure Regulator: Regulates pressure under the control of the controller 19.

60—User Interface: an means for a user to interact with the system, comprising user input devices and user output devices.

61—On/Off Button.

62—Fan Selector Button: Activates the increase/decrease buttons to set the fan speed.

63—Increase Button: Used to increase a user input value.

64—Decrease Button: Used to decrease a user input value.

65—Mode Selector: Enables the user to select a desired mode of operation.

66—Temperature Display: Displays the current temperature of a predetermined system element.

67—Tachometer: Displays the current speed of the fan.

68—Load Indicator: Displays the load on the engine as a percentage of its rated power.

69—Speed Selector: Used to set the level of a predetermined system element.

70—General Indicator: Displays the current speed of the element set using selector 69.

71-75: Method steps of a procedure for starting up the system.

76-79: Method steps of a procedure for shutting down the system.

The invention has been described with reference to illustrations of aspects of the disclosed systems, methods, and apparatus according to example embodiments of the invention. The invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. Accordingly, the disclosed embodiments are to be considered in all respects as illustrative and not restrictive. Many modifications and other embodiments of the invention will come to mind to one skilled in the art to which this invention pertains and having the benefit of the teachings presented in the present disclosure and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. For example, suitable methods and materials may have been described, although other methods and materials similar to or equivalent to those described herein may be used in the practice or testing of the present invention. Thus, the present invention is to be accorded the widest scope consistent with the principles and features disclosed herein.

Claims

1. A flameless heater, comprising: a plurality of radiant heat sources maintained at a higher temperature than ambient air outside of the heater, including an engine that produces heat as it generates motive power, and an air compressor that produces heat as it compresses air;a structure arranged to receive ambient air and conduct it past the radiant heat sources;a fan to force ambient air through the structure to heat the air; anda duct to deliver the heated air to a desired location.

2. The heater of claim 1, further comprising: a radiator thermally coupled to the engine;an exhaust heat exchanger thermally coupled to an engine exhaust; andan air compressor heat exchanger thermally coupled to the air compressor;wherein the air is heated as it is forced past the radiator and the heat exchangers.

3. The heater of claim 2, wherein the air compressor is a rotary screw compressor.

4. The heater of claim 2, further comprising: at least one pressure regulator and flow regulator;wherein the fan is driven by pneumatic pressure from the air compressor, and the pressure/flow regulators are operatively coupled between the air compressor and the fan to control the speed of the fan.

5. The heater of claim 2, further comprising: a hydraulic pump coupled to the engine to use at least a portion of the motive power to drive the pump; anda proportional valve;wherein the fan is driven by hydraulic pressure from the hydraulic pump, and the proportional valve is operatively coupled between the hydraulic pump and the fan to control the speed of the fan.

6. The heater of claim 1, further comprising: at least one sensor arranged to sense an aspect of the heater related to the production and delivery of heat;at least one control component operable to control a respective aspect of the heater sensed by the sensors; anda controller operatively coupled to the sensors and to the control components, arranged to control the production and delivery of forced heated air based on the sensed conditions using the control components.

7. The heater of claim 6, further comprising a user interface operatively coupled to the controller, the user interface comprising at least one input device for receiving a user input to influence operation of the control components, and at least one output device for providing a user output related to the sensed conditions.

8. The heater of claim 7, wherein the controller is arranged to receive and group the sensed input signals from all of the sensors, and to output control signals based on the sensed input signals and the user inputs to control the control components.

9. The heater of claim 8, wherein the controller controls the production and delivery of forced heated air by controlling all of the control devices based on all of the sensed conditions and all of the user inputs.

10. The heater of claim 9, wherein the heater functions as a thermostat to maintain the temperature of an enclosed space warmer than the ambient air.

11. The heater of claim 1, further comprising a chassis fixedly coupled to the source of radiant heat, the air mover, and the duct.

12. The heater of claim 11, wherein the chassis comprises a structural frame mounted on one of a skid and a wheeled trailer.

13. The heater of claim 11, wherein the chassis further comprises an enclosure arranged to mitigate heat escaping from the heater in an uncontrolled manner.

14. The heater of claim 13, further comprising: an intake grill to direct the flow of ambient air into the enclosure; andat least one of a duct and a baffle to direct the flow of the intake air through the enclosure.

15. The heater of claim 11, further comprising a water separator to remove water from one or more of the heater components.

16. A method of starting a flameless heater, comprising: receiving a start signal from a start device operated by a user;receiving user input settings from input devices of a user interface operated by the user;starting an engine of the heater that generates motive power and produces heat;monitoring the temperature of engine coolant circulating through the engine;after the engine coolant temperature rises to a predetermined threshold, starting an air compressor coupled to the engine that uses at least a portion of the motive power to compress air and produces heat as the air is compressed;starting a fan to force air past: a radiator thermally coupled to the engine;a heat exchanger thermally coupled to an exhaust port of the engine; andan air compressor heat exchanger thermally coupled to the air compressor;whereby the forced air is heated; andconducting the forced heated air through a duct to provide heat to a desired location.

17. The method of claim 16, further comprising automatically: controlling a speed of the fan to achieve a predetermined temperature of the forced heated air;sensing a plurality of conditions of aspects of the heater related to the production and delivery of the heated air; andcontrolling a plurality of control components based on the sensed conditions to control the production and delivery of the forced heated air.

18. The heater of claim 17, further comprising: monitoring the sensed conditions; andadjusting at least one of the control components to maintain at a predetermined level the production and delivery of the forced heated air.

19. A method of stopping a flameless heater, comprising: receiving a stop signal from a stop device operated by a user;unloading an air compressor of the heater; andunloading an engine of the heater that drives the air compressor.

20. The method of claim 19, further comprising: executing a phased procedure to shut off the heater in a manner designed not to damage any aspect of the heater.