| US 7,546,733 B2 | ||
| Method for controlling operation of cylinder apparatus | ||
| Takeshi Nakada, Tsuchiura (Japan); Kazuhiro Tanaka, Chikushino (Japan); Yasuo Sakurai, Kazo (Japan); Hiromichi Kajikawa, Ibaraki-ken (Japan); and Takeshi Seo, Nagareyama (Japan) | ||
| Assigned to SMC Kabushiki Kaisha, Tokyo (Japan) | ||
| Filed on Sep. 01, 2006, as Appl. No. 11/469,662. | ||
| Claims priority of application No. 2005-260556 (JP), filed on Sep. 08, 2005. | ||
| Prior Publication US 2007/0051405 A1, Mar. 08, 2007 | ||
| Int. Cl. F01B 21/04 (2006.01) | ||
| U.S. Cl. 60—711 | 5 Claims |
| 5. A method for controlling operation of a cylinder apparatus comprising a piston which is provided displaceably in a cylinder
body, a ball screw which is engaged with said piston, and a driving section which drives and rotates said ball screw, wherein
said piston is displaced by a driving force of said driving section and a pressure of a pressure fluid supplied to a cylinder
chamber of said cylinder body to move a workpiece attached to said piston, said method comprising the steps of:
applying a weight load to said piston, said weight load applied to said piston fluctuating during a displacement range of
said piston;
displacing said piston along said cylinder body by said ball screw under a driving action of said driving section;
performing, during a portion of said displacement range, a step of supplying said pressure fluid to said cylinder chamber
at a pressure corresponding to fluctuation of said weight load before said weight load applied to said piston is fluctuated
so that a pressing force, which is substantially balanced with said weight load, is applied to said piston, and performing,
during another portion of said displacement range, a step of detecting a driving torque of said driving section to compare
said driving torque with a preset driving torque of said driving section set in a control unit, and calculating a pressure
of said pressure fluid to be supplied corresponding to a difference between said preset driving amount and said driving amount
detected to supply said pressure fluid to said cylinder chamber based on the calculated pressure; and moving said piston by
said driving force brought about by said driving section and said pressing force brought about by said pressure fluid.
|