US 20050016978 A1
A cooling system connected to provide coolant to a welding-type component automatically circulates coolant through the welding component upon activation of the welding component. A controller is configured to regulate the cooling system such that upon activation of the welding-type component coolant is caused to at least flow through the welding-type component and circulate after deactivation of the welding torch until a temperature of the coolant falls below a certain value or a specified time period has expired. The cooling system is constructed to be integrally disposed within a power source housing.
24. A welder comprising:
a welding torch configured to present an electrode to a weld;
an enclosure defined by a base plate, a pair of side plates, a pair of end plates, and a top cover;
a power conditioner disposed within the enclosure and configured to condition raw power into a form usable in a welding process; and
a cooling system disposed within the enclosure and designed to circulate coolant through the welding torch connected to the enclosure.
25. The welder of
26. The welder of
27. The welder of
28. The welder of
29. The welder of
30. The welder of
31. The welder of
32. The welder of
33. The welder of
34. A welding-type power source comprising:
a power supply circuit disposed in the enclosure and configured to receive a raw power input and provide a power output usable by a welding-type process; and
a cooling system disposed in the enclosure and configured to circulate coolant to regulate a temperature in at least the enclosure.
35. The welding-type power source of
36. The welding-type power source of
37. The welding-type power source of
38. The welding-type power source of
39. The welding-type power source of
40. A welding system comprising:
a power source connectable to a coolant-cooled welding torch;
a cooling system disposed in the power source and configured to circulate coolant to at least the welding torch during a welding process; and
at least one check valve integrated with the cooling system and biased to prevent coolant leakage from the power source when the welding torch is disconnected from the power source.
41. The system of
42. The system of
a coolant tank;
a pump assembly configured to draw coolant from the coolant tank and deliver coolant to the welding torch; and
a heat exchanger configured to lower a temperature of coolant being reclaimed from the welding torch.
43. The system of
The present invention relates generally to welding-type systems and, more particularly, to a method and apparatus of an automatically and conditionally cooling a welding-type system upon activation of the welding-type system. More particularly, the invention relates to circulating coolant automatically through a power source and a welding-type torch upon initiation of a welding-type process.
It is well known that certain welding processes such as heavy-duty TIG (tungsten inert gas) welding generate considerable amount of heat during the welding process. A welding component or welding torch is commonly used to hold a tungsten electrode that is heated to join metals through heat transfer. Because tungsten is a rare metallic element with an extremely high melting point (approximately 3410°), the electrode can withstand a tremendous heat load and use the heat to join metals with filler material. The heat generated, however, can cause the welding torch to become increasingly heated. A cooling system is typically required to prevent overheating of the torch. Generally, the welding torch is liquid-cooled with coolant, such as water, which is supplied from a coolant source remote from the power source. The welding torch may also be air cooled.
One of the drawbacks with these standard cooling systems is that the cooling system is manually operable. That is, a typical cooling system is equipped with an ON/OFF switch that requires an operator to manually turn on the cooling system at the commencement of the welding process. When the cooling system is activated, coolant is caused to circulate through the power source and the welding torch. It can therefore be problematic if the operator forgets to turn the cooling system on before commencing welding. As a result, the temperature of the torch quickly rises to maximum acceptable limits and if not immediately cooled, can cause the torch to break down and malfunction. It is also costly to interrupt the welding process and allow the torch to cool. Moreover, the operator may forget to turn off the cooling system during extended periods of downtime. As such, the cooling system continues to circulate coolant to the welding torch even when cooling is not needed which increases energy consumption.
Another disadvantage of manually actuated cooling system rests in that the operator may turn off the cooling system prematurely following completion of a welding session. It may take several minutes following welding termination for the temperature of the torch to drop below an acceptable set point. However, if the operator prematurely shuts down the cooling system, the temperature of the torch may actually increase for a short and potentially damaging period. These drawbacks can significantly reduce the life expectancy of the cooling system and/or torch and increase the overall energy consumption of the system. All of which increases the costs of the welding system.
Therefore, it would be desirable to design a cooling system that automatically circulates coolant through at least the welding torch upon activation of the torch or commencement of the welding process and maintains coolant flow until the temperature of the torch falls below a specified set point or expiration of a prescribed time period that is of sufficient length to allow the torch to cool to below the specified set point.
The present invention solves the aforementioned problems by providing a cooling system with associated circuitry and sensory devices that causes coolant to flow in a torch of a welding system automatically upon activation of the torch or commencement of welding at a weld. Commencement of the welding process occurs when a welding arc is struck between an electrode and a workpiece. The cooling system is configured to circulate the coolant through the torch for a set period of time after deactivation of the torch or until temperature of the torch falls below a temperature set point.
There are a large number of welding processes available for use in industry. These welding processes include gas tungsten arc, oxygen gas welding, and shielded metal arc welding. The gas tungsten arc welding process is generally referred to as TIG (tungsten inert gas) welding. A typical TIG welding apparatus includes a welding component which is commonly referred to as welding torch and is designed to introduce a tungsten electrode to a weld. The welding torch holds the electrode which is heated to extremely high temperatures by electrical power received from the power source. The welding torch is designed to introduce the electrode to a weld such that the electrode “scratches” the workpiece and is removed therefrom. At appropriate voltage and current, a welding arc is created between the electrode and the workpiece. The torch typically includes a trigger mechanism for initiating the welding process, i.e., closing the circuit between the workpiece and the power source.
Accordingly, one aspect of the present invention includes a welding-type component configured to present an electrode to a weld. A cooling system is configured to automatically circulate liquid coolant through at least the welding-type component upon activation of the welding-type component.
In accordance with another aspect of the invention, a welding apparatus includes an enclosure having a power source and a cooling system disposed therein. A welding torch is connected to both the power source and the integrated cooling system. A controller is configured to regulate the integrated cooling system such that, upon activation of the welding torch, coolant is caused to at least flow through the welding torch and continue to circulate after deactivation of the welding torch until a temperature of the torch or coolant falls below a certain value.
In accordance with yet another aspect of the invention, a method for cooling a welding-type component includes the step of detecting activation of a welding-type component. The method further includes that the steps automatically circulating coolant through the welding-type component upon activation of the welding-type component and maintaining coolant circulation through the welding-type component for a limited period after the welding-type component is deactivated.
Various other features, objects and advantages of the present invention will be made apparent from the following detailed description and the drawings.
The drawings illustrate one preferred embodiment presently contemplated for carrying out the invention.
In the drawings:
Enclosed in the enclosure 14 are the welding-type power source and a cooling system. The power source is constructed to condition raw power from a power supply into a power suitable for welding. In the preferred embodiment, the welding-type power supply and cooling system are disposed within the common enclosure 14. The cooling system is designed to circulate coolant through the torch 32 via coolant conduit 42. The coolant system is designed such that coolant automatically flows into the torch when the welding process begins, i.e., the torch is activated or an arc is stuck. Alternately, the integrated cooling system may be remote from the power source.
Controller 50 is adapted to electronically communicate with the cooling system to effectuate automatic commencement of coolant circulation to torch 32 when the welding process begins. The controller 50 is also connected to a temperature sensor 54 designed to provide feedback as to the temperature of the torch and/or the coolant within the torch as well as a pressure sensor or flow meter 56 to provide feedback regarding coolant pressure in the system. In this regard, controller can regulate pump 48 to increase or decrease the pressure or flow of coolant to and from the torch. The temperature sensor 54 provides temperature feedback to the controller such that circulation is maintained after a welding process is complete if the temperature exceeds a specified set point. Controller 50 may also include a timer that regulates or maintains coolant circulation for a specified period. The timer is designed to define a cool-down period of sufficient duration to allow the torch to cool.
Cooling system also includes a motor assembly 58 to drive pump 48 and a heat exchanger 60 and fan assembly 61 operationally connected to one another to remove the heat carried by the coolant from the torch. During one operational embodiment, the pump 48 draws coolant from tank 46 and delivers the coolant to torch 32 through coolant path 49. The coolant absorbs heat from the torch and carries the heated coolant to heat exchanger via path 62. The heat exchanger 60 may include a coiled radiator to remove the heat from the coolant to the surrounding atmosphere and dissipated by fan 61. The cooled coolant is then re-deposited in tank 46 and further allowed to cool before re-circulated back to torch 32. As illustrated, cooling system 44 is integrated within the welder or power source 12. However, the cooling system 44 may be a modular or portable unit separately mounted to the power source or other welding or transport equipment.
Cooling system 44 further includes a check valve 63 in coolant supply path 49 that is biased such that coolant is prevented from flowing out of the system when torch 32 is not connected to the power source. Additionally, the system may be constructed with additional multiple check valves, i.e. check valve 69 in the coolant return path 62, to further regulate coolant flow. The check valves are designed to prevent coolant flow when the torch is not connected or when the power source is being serviced and the like. Limiting coolant flow is advantageous under certain situations because of the high voltage characteristics of the power source as well as limiting exposure to the internal electronic components of the power source.
Cooling system 44 is designed such that coolant is supplied to tank 46 through a spout 65 that extends externally of the power source 12. Having spout 65 extending outside the power source frame reduces and, preferably, eliminates accidental coolant and internal power source component contact. Tank 46 is preferably constructed to hold approximately two gallons of coolant, such as water.
A coolant level indicator 67 is provided for real-time status of coolant level in the tank. Indicator 67 is preferably mounted externally to the frame of the power source. Additionally, controller 50 may be connected to level indicator 67 such that warnings (audio and visual) may be activated if the coolant falls below acceptable levels.
Referring now to
The algorithm also instructs the controller to regulate coolant flow based on coolant pressure in the system. As such, break-down in coolant lines or other failures in the cooling system that affect the amount and force of coolant flow are readily identified. An excessive flow condition may indicate that coolant supply pressure has exceeded a maximum level signaling malfunction of the pump and/or motor. Similarly, an insufficient flow condition may indicate a failure of the coolant supply or a general blockage of the coolant supply or return lines. Therefore, the controller 50 detects at step 120 whether coolant pressure is within acceptable limits. If so 120 a, circulation continues at 106. If not 120 b, the controller determines whether a pressure override has been selected at step 122. If so 122, 122 a, coolant flow continues despite the pressure being outside acceptable limits. If not 122, 122 b, coolant circulation ceases and the cooling system is returned to stand-by state at 116.
The heretofore described steps are to be repeatedly executed by one or more processors. For example, the steps of the algorithm are carried out repeatedly every 10 ms by a microprocessor in the power source or cooling system. As such, once the cooling system is placed in stand-by mode, the controller switch confirms that a valid arc has been struck or other indicators that welding has recommenced such as a manual start before recommencement of coolant circulation.
Accordingly, one embodiment of the present invention includes a welding-type component configured to present an electrode to a weld. A cooling system is configured to automatically circulate liquid coolant through at least the welding-type component upon activation of the welding-type component.
In accordance with another embodiment of the invention, a welding apparatus includes an enclosure having a power source and a cooling system disposed therein. A welding torch is connected to both the power source and the integrated cooling system. A controller is configured to regulate the integrated cooling system such that, upon activation of the welding torch, coolant is caused to at least flow through the welding torch and continue to circulate after deactivation of the welding torch until a temperature of the torch or coolant falls below a certain value.
In accordance with yet another embodiment of the invention, a method for cooling a welding-type component includes the step of detecting activation of a welding-type component. The method further includes that the steps automatically circulating coolant through the welding-type component upon activation of the welding-type component and maintaining coolant circulation through the welding-type component for a limited period after the welding-type component is deactivated.
As one skilled in the art will fully appreciate, the heretofore description of welding devices not only includes welders, but also includes any system that requires high power outputs, such as heating and cutting systems. Therefore, the present invention is equivalently applicable with any device requiring high power output, including welders, plasma cutters, induction heaters, and the like. Reference to welding power, welding-type power, or welders generally, includes welding, cutting, or heating power. Description of a welding apparatus illustrates just one embodiment in which the present invention may be implemented. The present invention is equivalently applicable with many high power systems, such as cutting and induction heating systems, or any similar systems.
The present invention has been described in terms of the preferred embodiment, and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims.