Patent Application
20210017902
The present disclosure relates to engine driven generators, and in particular to engine driven arc generation devices, such as welders and plasma cutters.
Engine driven welders include an internal combustion engine, such as a diesel, gasoline or liquefied petroleum gas (LPG) engine. The engine drives a generator, and the generator supplies electrical power to a welding power supply that outputs a welding current and voltage. A compact design for an engine driven welder is often desirable. However, it can be difficult to maximize the machine's fuel storage capacity when a compact design is employed. For example, space for the fuel tank will be limited, and various obstructions in the structural chassis that occupy potential fuel tank space may be present. A compact design for an engine driven welder that maximizes fuel storage capacity would be beneficial. The generator is cooled by a fan that rotates with the generator's rotor to move air through the generator. Air that exits the generator can be quite hot and can undesirably heat nearby components within the engine driven welder. Reducing such heating would be beneficial. Engine driven welders can include auxiliary loads or equipment that are powered by the engine. Examples of such auxiliary loads include air compressors and hydraulic pumps. A drive mechanism is required to power the auxiliary loads.
The following summary presents a simplified summary in order to provide a basic understanding of some aspects of the devices, systems and/or methods discussed herein. This summary is not an extensive overview of the devices, systems and/or methods discussed herein. It is not intended to identify critical elements or to delineate the scope of such devices, systems and/or methods. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later.
In accordance with one aspect of the present invention, provided is a welding machine. The welding machine includes a welding power supply, and a chassis structure that at least partially forms an engine compartment. An internal combustion engine is located within the engine compartment. A generator is operatively connected to the welding power supply to supply electrical energy to the welding power supply. The generator comprises a rotor shaft driven by the internal combustion engine. The welding machine includes an air compressor or a hydraulic pump comprising a driven pulley. An axial generator cooling fan is driven by the rotor shaft of the generator. The axial generator cooling fan comprises a plurality of fan blades extending between a central hub that is attached to the rotor shaft and an annular pulley ring connecting the fan blades. The annular pulley ring is coupled to the driven pulley to power the air compressor or the hydraulic pump. A fuel tank is mounted within the chassis structure and is located beneath both of the internal combustion engine and the generator. The axial generator cooling fan generates a first cooling air flow that cools the generator, and a second cooling air flow that cools the fuel tank.
In accordance with another aspect of the present invention, provided is a welding machine. The welding machine includes a welding power supply, and a chassis structure comprising a divider wall that at least partially defines an engine compartment of the welding machine. A generator is operatively connected to the welding power supply to supply electrical energy to the welding power supply. The generator comprises a rotor shaft. An internal combustion engine is connected to drive the rotor shaft of the generator. An axial generator cooling fan is driven by the rotor shaft of the generator. The axial generator cooling fan comprises a plurality of fan blades extending between a central hub attached to the rotor shaft and an annular pulley ring connecting the fan blades. An auxiliary load comprising a driven pulley is coupled to the annular pulley ring of the axial generator cooling fan. The axial generator cooling fan powers the auxiliary load via the annular pulley ring. A cantilevered engine-mounting shelf that is cantilevered from the divider wall. The internal combustion engine is attached to the cantilevered engine-mounting shelf. A fuel tank is mounted within the chassis structure and is located beneath both of the cantilevered engine-mounting shelf and the internal combustion engine.
In accordance with another aspect of the present invention, provided is an electrical power generation apparatus comprising an internal combustion engine. An electric generator is coaxially coupled to the internal combustion engine. The electric generator comprises a rotor shaft driven by the internal combustion engine. An axial generator cooling fan is driven by the rotor shaft of the electric generator. The axial generator cooling fan comprises a plurality of fan blades extending from a central hub that is attached to the rotor shaft, and an annular pulley ring encircling the fan blades. An auxiliary load comprising a driven pulley is coupled to the annular pulley ring of the axial generator cooling fan. The axial generator cooling fan powers the auxiliary load via the annular pulley ring. A chassis structure comprising a bulkhead separates an engine compartment from another compartment of the electrical power generation apparatus. A vibration isolator is mounted to the bulkhead, and an engine-mounting shelf is cantilevered from the bulkhead and is isolated from the bulkhead by the vibration isolator. A fuel tank is mounted within the chassis structure and is located beneath each of the engine-mounting shelf, the internal combustion engine and the electric generator.
Embodiments of the present disclosure relate to engine driven welders. The embodiments will now be described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. It is to be appreciated that the various drawings are not necessarily drawn to scale from one figure to another nor inside a given figure, and in particular that the size of the components are arbitrarily drawn for facilitating the understanding of the drawings. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It may be evident, however, that the present invention can be practiced without these specific details. Additionally, other embodiments of the invention are possible and the invention is capable of being practiced and carried out in ways other than as described. The terminology and phraseology used in describing the invention is employed for the purpose of promoting an understanding of the invention and should not be taken as limiting.
As used herein, “at least one”, “one or more”, and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together. Any disjunctive word or phrase presenting two or more alternative terms, whether in the description of embodiments, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” should be understood to include the possibilities of “A” or “B” or “A and B.”
The welding machine 10 includes a base 12 that is part of a chassis structure for the welding machine, and an outer case or enclosure 14. A user interface 16 for controlling the operation of the welding machine 10 is located on the front side of the outer case 14. Example welding processes that can be performed by the welding machine include shielded metal arc welding (SMAW), gas metal arc welding (GMAW), flux-cored arc welding (FCAW), gas tungsten arc welding (GTAW), and gouging.
The case 14 includes various access doors. Doors 18 along the left and right lateral sides of the welding machine 10 provide access to an engine compartment. In certain embodiments, the doors 18 are hinged at their bottom edges, allowing the doors 18 to swing downward. The doors 18 can be easily removable from the hinges, so that they can be relocated away from the welding machine 10 when accessing the engine compartment. A door 20 on the top of the welding machine 10 also provides access to the engine compartment. The top door 20 can be aligned with an air filter housing for the engine, so that the air filter can be readily inspected and replaced.
One or more doors 22 on the front side of the welding machine 10 provide access to various electrical outputs of the welding machine. For example, auxiliary power receptacles and welding torch connections can be accessed via the doors 22 on the front of the welding machine 10.
Beneath the doors 22 on the front side of the welding machine is a removable battery compartment cover 24. The battery compartment cover 24 is shown in an unattached, open position in
As noted above, air that exits the generator 30 can be quite hot and can heat other components within the welding machine. For example, a generator with Class H winding insulation may have exit or discharge air temperatures of 110° C. or higher. This hot exit air could flow over a fuel tank of the welding machine, or across another component of the welding machine that is negatively impacted by high heat. It is desirable to maintain the fuel temperature below a specific threshold, such as 50° C. for example, and maintaining the fuel temperature becomes more difficult when the fuel tank is heated by the generator 30. Increasing the volume of airflow through the generator 30 will lower the exit air temperature from the generator. To create an increased airflow through the generator 30, the generator includes both a radial generator cooling fan 31 and an axial generator cooling fan 33. Both fans 31, 33 are mounted on or otherwise driven by the rotor shaft 35 of the generator 35. As the engine 28 turns the rotor shaft 35, both fans 31, 33 operate together to cool the generator 30. The axial generator cooling fan 33 is configured to push air axially through the generator housing, and the radial generator cooling fan 31 is configured to pull the air axially through the generator housing and expel the air radially from the housing. The radial generator cooling fan 31 can be located within the generator housing, and the axial generator cooling fan 33 can be located external to the housing to push air into the housing through an inlet. In certain embodiments, the axial generator cooling fan 33 can be used to cool additional components within the welding machine 10, such as the fuel tank. For example, operation of the axial generator cooling fan 33 can create a first cooling air flow that helps to cool the generator, and additional cooling air flows that cool the fuel tank, muffler, electronic components, etc.
The welding machine 10 can include an auxiliary load 37 that is mechanically driven by the engine 28. Examples of auxiliary loads 37 include air compressors and hydraulic pumps. The auxiliary load 37 can include a clutch 39, such as an electromagnetic clutch, to engage and disengage the auxiliary load. The auxiliary load 37 can further include a driven pulley 41, chain ring, gear, etc. that couples the auxiliary load to the output of the engine, such as via a drive belt 43, drive chain, etc. In certain embodiments, the auxiliary load 37 is driven by the engine 28 via a drive pulley 45 attached to the axial generator cooling fan 33. When the axial generator cooling fan 33 rotates with the clutch 39 on the auxiliary load 37 engaged, engine power is transferred to the auxiliary load via the drive belt 43, which couples the drive pulley 45 on the fan to the driven pulley 41 on the auxiliary load.
The welding machine 10 includes an engine-mounting shelf 42 or bracket that is cantilevered from an internal wall or bulkhead of the machine's chassis structure. Cantilevering the engine-mounting shelf 42 removes the engine's mounting system from the bottom of the chassis structure and frees up space for maximizing the size of the fuel tank 44. The engine's mounting system does not intrude into usable fuel tank volume within the engine compartment. The fuel tank 44 is mounted within the chassis structure and extends from a point just behind the battery compartment 26 to the rear of the welding machine 10, and the fuel tank 44 is located beneath the engine 28, the engine-mounting shelf 42, the generator 30 and a mounting bracket 46 for the generator.
The engine-mounting structure is shown in detail in
It can be seen that the engine-mounting shelf 42 in the illustrated embodiment has a trapezoidal shape. The engine-mounting shelf 42 need not have a trapezoidal shape and could have a square or rectangular shape for example. However, the trapezoidal shape provides the advantages of reduced torque/force on the vibration isolators 52 and the fasteners extending therethrough, while reducing the weight of the engine-mounting shelf 42. Locating the vibration isolators 52 far apart on the divider wall 50 helps to minimize the side-to-side rocking of the engine. The trapezoidal shape of the shelf 42 reduces the weight of the shelf by narrowing it near the engine mounts. It can be seen that the nonparallel sides 54, 56 of the engine-mounting shelf 42 extend away from the divider wall and converge, and would extend into the engine compartment of the welding machine. The edges of the nonparallel sides 54, 56 of the engine-mounting shelf 42 are upturned to form strengthening flanges that extend vertically away from the upper surface 58 of the shelf. Alternatively, the edges can extend downwards to form the strengthening flanges. In either case, the strengthening flanges stiffen the shelf 42 to support the weight of the engine. The engine is mounted to the upper surface 58 of the engine-mounting shelf 42. The engine-mounting shelf 42 can include holes 60 for fasteners to secure the engine to the shelf, and slots 62 for hanging the shelf from the vibration isolators 52. To reduce the weight of the engine-mounting shelf 42, or to allow air to flow through the shelf, the shelf can include one or more cutout portions 63.
Returning to
At the bottom of the chassis structure nestled within the base 12 is the fuel tank 44. The base is not shown in
The fuel tank 44 can occupy nearly the entire floor space of the engine compartment 64 formed by the base 12. The fuel tank 44 can extend from the divider wall 50 to a point rearward of the generator-mounting bracket 46. The fuel tank 44 can occupy such a considerable amount of the floor space of the engine compartment 64 because the mounting system for the engine 28 does not intrude into the floor space. Thus, the fuel tank 44 can be located beneath each of the engine-mounting shelf 42, the engine 28, the generator 30, the generator-mounting bracket 46 and the muffler 66. The base 12 of the chassis structure has raised side walls, a raised rear wall, and a forward wall formed by the divider wall 50, and the fuel tank 44 can extend substantially to each of these four walls. Further, the engine 28 and generator 30 need not be supported by the fuel tank 44, but rather can be borne by their respective support structures (e.g., engine-mounting shelf 42 and bracket 46 and associated vibration isolators) and held just above the fuel tank.
The right and left lateral sides of the enclosure 14 include recessed air channels 76, 78 that extend rearward from the vents 72, 74 along the sides of the enclosure (e.g., along the engine compartment). The depth of the air channels 76, 78 can increase from back to front in a linear or non-linear fashion, so that the air channels are tapered. The recessed vents 72, 74 and air channels 76, 78 are less likely to be obstructed when the welding machine 10 is placed close to another object, as compared to vents located directly on a side surface of the machine. Moreover, the effective open area provided by the recessed vents 72, 74 can be made larger than conventional stamped louvered vents located on a side surface of the machine. Large intake vents 72, 74 provide a slower air flow, which reduces noise and the decreases the likelihood of drawing contaminants into the enclosure 14.
The recessed side vents 72, 74 and air channels 76, 78 are located well above the base 12, and can be located high on the machine, such as in the upper one-third or upper one-quarter of the machine's height, or lower, such as in the upper two-thirds or upper one-half of the machine's height. In the embodiment shown in the drawings, the recessed side vents 72, 74 and air channels 76, 78 are located above the engine compartment access doors 18 in an upper portion of the welding machine 10. The electronics compartment 48 is also located in an upper portion of the welding machine 10, above the battery compartment 26. Locating the side air intake vents 72, 74 and electronics compartment 48 in an upper portion of the welding machine 10 allows access to the starting battery 32 and battery compartment 26 to be provided at the front of the machine. Further, placing the vents 72, 74 above the base 12 reduces the likelihood that contaminants, such as dirt, rain, or snow, will be sucked into the welding machine 10. Engine noise emitted through the recessed side vents 72, 74 will tend to propagate away from the front of the welding machine 10 and away from an operator located at the front of the welding machine.
Cooling air flows into and out of the welding machine 10 as shown schematically by arrow in
Air is expelled from the engine compartment 64 through discharge vents 84 in the sides and/or rear of the outer case 14. The discharge vents 84 can also be located in the upper two-thirds or upper half of the outer case 14. Discharging the cooling air at the top of the welding machine 10 helps to project engine noise upwards and away from the operator.
The rear surface of the outer case 14 includes an air intake vent 88 for the generator 30. Through the air intake vent 88, ambient air is pushed/pulled into the generator housing by the axial 33 and radial 31 (
The axial generator cooling fan 33 has a central hub 90 that is mounted on or attached to the rotor shaft of the generator 30, at the rear of the generator. A plurality of fan blades 92 extend from the central hub 90. The axial generator cooling fan 33 further includes an annular pulley ring 45 for driving an auxiliary load 37, such as an air compressor or a hydraulic pump. The annular pulley ring 45 encircles the fan blades 92. In certain embodiments, the annular pulley ring 45 connects the fan blades 92 together, so that the fan blades extend from the central hub 90 to the annular pulley ring. The fan 33 may be formed as a monolithic component, with the central hub 90, blades 92, and annular pulley ring 45 being one piece.
The annular pulley ring 45 is a drive pulley for the auxiliary load 37. A drive belt 43 or similar device couples the annular pulley ring 45 to the driven pulley 41 on the auxiliary load 37. The clutch for engaging and disengaging the auxiliary load 37 can be built into auxiliary load, and is not shown in
The auxiliary load 37 can be attached to the mounting bracket 46 for the generator 30, and the fuel tank 44 can extend beneath the auxiliary load. Locating the pulleys and drive belt at the rear of the machine and external to the generator housing improves serviceability. For example, the belt 43 can be replaced without removing the end cap of the generator 30.
In certain embodiments, some of the airflow created by the axial generator cooling fan 33 can be directed away from the generator 30 to cool other components in the engine compartment, such as the fuel tank 44 for example. After cooling such other components, the redirected airflow can combine with the cooling air that is discharged from the generator housing 82 and pass through the outer case of the welding machine.
It should be evident that this disclosure is by way of example and that various changes may be made by adding, modifying or eliminating details without departing from the fair scope of the teaching contained in this disclosure. The invention is therefore not limited to particular details of this disclosure except to the extent that the following claims are necessarily so limited.
