Electric heating – Metal heating – By arc
Patent
1992-06-25
1994-01-11
Shaw, Clifford C.
Electric heating
Metal heating
By arc
219 7615, B23K 904
Patent
active
052783910
DESCRIPTION:
BRIEF SUMMARY
DESCRIPTION
1. Technical Field
This invention relates to an unbalance correction method for rotating bodies such as a turbine assembly of a torque converter etc.
2. Background Art
A rotating body such as a turbine assembly for a torque converter will vibrate during high-speed rotation, when its mass is distributed non-uniformly relative to a rotating shaft. In order to avoid such vibration, it is required to make the mass of rotating body uniform relative to the rotating shaft. To this end, an unbalance has been adjusted by making a hole on an unbalanced position of the rotating body to reduce the mass, or by attaching a balance weight to increase the mass. The following four methods have been used in order to increase the mass by attaching the weight: resistance welding, etc.
In the above methods [1], [2] and [3], however, problems such as an increase in labor cost and unevenness of quality have occurred because of difficulty in automating the welding operation and the necessity of hand work. Although it easy to automate the welding operation in the above method [4], there have been problems due to the necessity for after-processes such as washing and removal work and the contamination of parts of an automatic transmission for a torque converter, for example, which presents a very severe limitation on the contamination of parts. That is, spatter or scale has been produced in the built-up welding carried out by ordinary arc welding, so that it has been necessary to wash and remove the spatter or scale by after-processes. Further, because of a very thin thickness (approx. 1.2 mm) of the turbine assembly at its unbalance position of mass, a penetration-to-backside has occurred due to penetration of mother material of a turbine assembly, or scale (backside-burning) has been produced at a backside of the mother material so as to worsen a quality of the turbine assembly in the built-up welding carried out by ordinary arc welding. Further, there has been a problem that, because of occurrence of the penetration-to-backside or the backside-burning, only a small amount of built-up welding has been possible so that it has been a problem in the art to perform effective correction.
DISCLOSURE OF THE INVENTION
This invention has been made in order to solve the above problems, and an object of the invention is to provide an unbalance correction method for a rotating body, which can be automated easily, does not cause deterioration of a quality of the rotating body, and can perform exact and effective correction.
This invention provides an unbalance correction method for a rotating body, in which an unbalance of the rotating body is corrected by carrying out a built-up welding at an unbalance position of the rotating body, characterized in that a filler metal is brazed to the welding position by means of TIG welding while changing an intensity of the produced arc by pulse control under an inert gas atmosphere created at a backside of a welding position of the rotating body. Since the backside of the welding position of the rotating body is put under the inert gas atmosphere in the present invention, the scale is not produced at the backside of the welding position at the time of the welding.
Since the arc is produced by the pulse control while being changed in its intensity, the molten state of the filler metal is also changed in its intensity so that a temperature rise on a surface at the welding position is controlled. Therefore, the penetration-to-backside due to penetration at the welding position is not produced so that it becomes possible to apply a large amount of padding.
As described above, the back-burning and the penetration-to-backside can be prevented so that the quality of the rotating body is not reduced.
The unbalance is corrected by the brazing and built-up welding of filler metal, so that it becomes easy to automate the welding operation.
Owing to the TIG welding, spatter is not produced so that the washing and removal work are not necessary in the after processes.
BRIEF DESCRIPTION OF THE DRAWING
REFERENCES:
patent: 1489699 (1924-04-01), David
patent: 4295032 (1981-10-01), Sasaki
patent: 4445399 (1984-05-01), Sasaki et al.
patent: 4780593 (1988-10-01), Kato
Kabushiki Kaisha Daikin Seisakusho
Shaw Clifford C.
LandOfFree
Unbalance correction method for rotating body does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Unbalance correction method for rotating body, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Unbalance correction method for rotating body will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1633023