Back to results
US 6,557,379 B1Granted
Method of producing an arc tube
AssigneeKoito Manufacturing Co., Ltd.
InventorsMasakazu Nagasawa, Masayuki Umehara, Hiroshi Goto
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeKoito Manufacturing Co., Ltd.
InventorsMasakazu Nagasawa, Masayuki Umehara, Hiroshi Goto
Estimating the term…
A pair of chucks, which grip end portions of a cylindrical glass tube blank, are moved by a chuck moving mechanism toward each other, so that softened glass in an intermediate portion of the cylindrical glass tube blank is gathered, thereby forming a shape that is suitable for blow molding a light emitting tube portion. In the approaching movement, the position of one chuck is detected by using a laser position detector, and a result of the detection is fed back to the chuck moving mechanism, so as to control the approach distances of the chucks. The laser position detector detects the position of the chuck itself. Therefore, even when the positional relationship between the chuck and the chuck moving mechanism is varied, or backlash or deformation occurs in the chuck moving mechanism, the correct position of the chuck still is detected irrespective of such variation, backlash or deformation. Consequently, it is possible to effectively prevent the approach distances of the chucks from deviating from a desired value.
A method of producing an arc tube in which, in a process of producing an arc tube including a light emitting tube portion having a substantially elliptical spherical shape, said light emitting tube portion is formed in an intermediate portion of a cylindrical glass tube blank, said method comprising:
Dependencies are inferred from the claim text.