Patent application number | Description | Published |
20090009656 | SMA ACTUATOR DRIVING DEVICE, AND IMAGE PICKUP DEVICE INCORPORATED WITH THE SAME - In a shape memory alloy actuator driving device, a predetermined constant current is applied to a shape memory alloy member as a retrieval signal to detect a terminal voltage of the shape memory alloy member, and a detection result of the terminal voltage is compared with a target voltage value to be calculated based on a target resistance value of the shape memory alloy member and a value of the constant current to cause a driving circuit to output, to the shape memory alloy member, a drive current that makes the detection result substantially equal to the target voltage value. | 01-08-2009 |
20100257859 | SHAPE MEMORY ALLOY DRIVE DEVICE - A shape memory alloy drive device has drive control portion for displacing a shape memory alloy up to a target displacement value by applying a voltage or an electric current to the shape memory alloy by servo control, and also has contact detection portion for detecting a predetermined change in a drive control value, or, for example, a sharp increase in the drive control value, representing the amount of the voltage of the electric current applied by the drive control portion. When detecting a predetermined change, the contact detection portion determines that a movable portion having a lens etc. mounted thereon is in contact with a stationary mechanism. The shape memory alloy drive device further has drive limiting portion which, when the determination described above is made, causes the drive control portion to limit the target displacement value within a predetermined range. This limits an electric current flowing when the movable portion makes contact with the stationary mechanism, preventing overheating and excess stress. | 10-14-2010 |
20100296183 | DRIVING DEVICE MADE OF SHAPE-MEMORY ALLOY - A storing section ( | 11-25-2010 |
20100320943 | SHAPE MEMORY ALLOY DRIVER - A shape memory alloy driver comprises a displacement detection portion, a drive control portion, and a compensation calculation portion. The displacement detection portion detects displacement of a shape memory alloy based on a resistance value etc. detected from the shape memory alloy. The drive control portion applies a voltage or current to the shape memory alloy by servo control to thereby displace the shape memory alloy to a target displacement value fed from a microcomputer etc. The compensation calculation portion calculates a compensated displacement value from the detected displacement value and a variation—attributable to the environment temperature—of the drive control value which the drive control portion uses for controlling the voltage or current. Having been fed with the compensated displacement value, the drive control portion varies the drive control value such that the compensated displacement value is equal to the target displacement value. | 12-23-2010 |
20110031924 | SHAPE MEMORY ALLOY DRIVER - A shape memory alloy driver comprises a displacement detection portion, a drive control portion, and a compensation calculation portion. The displacement detection portion detects displacement of a shape memory alloy based on a resistance value etc. detected from the shape memory alloy. The drive control portion applies a voltage or current to the shape memory alloy by servo control to thereby displace the shape memory alloy to a target displacement value fed from a microcomputer etc. The compensation calculation portion calculates a compensated displacement value from the detected displacement value and a variation—attributable to the environment temperature—of the drive control value which the drive control portion uses for controlling the voltage or current. Having been fed with the compensated displacement value, the drive control portion varies the drive control value such that the compensated displacement value is equal to the target displacement value. | 02-10-2011 |
20110032628 | DRIVE DEVICE - A drive device includes a setting unit | 02-10-2011 |
20110071663 | POSITION CONTROL DEVICE, POSITION CONTROL METHOD, DRIVE DEVICE AND IMAGING DEVICE - A position control device | 03-24-2011 |
20110242398 | SHAPE MEMORY ALLOY ACTUATOR DRIVE DEVICE AND METHOD, AND IMAGING DEVICE USING THE SAME - A driving circuit ( | 10-06-2011 |