Patent application number | Description | Published |
20110147572 | ROTARY ENCODER AND ROTATION MECHANISM INCLUDING THE SAME - A rotary encoder includes two first detection units disposed at positions that are symmetrical about a rotation axis, each of the first detection units outputting an incremental signal, and second detection unit that outputs an absolute signal φ | 06-23-2011 |
20130096862 | ENCODER AND APPARATUS WITH THE SAME - The encoder includes a scale provided with a periodic pattern, a sensor relatively movable with respect to the scale and reading the periodic pattern to output analog signals each having a changing period corresponding to the periodic pattern and having mutually different phases, an A/D converter performing time-division analog-to-digital conversion on the analog signals output from the sensor to produce digital signals, and a phase detector detecting a phase from the digital signals. The encoder further includes a corrector calculating a correction value by using a relative movement speed of the scale and the sensor and the detected phase detected by the phase detector, and calculating a corrected phase from the correction value and the detected phase, and a position detector calculating a position in a direction in which the scale and the sensor are relativity moved by using the corrected phase. | 04-18-2013 |
20130099105 | ENCODER AND APPARATUS USING THE SAME - The encoder includes a scale including first and second periodic patterns, and a detector relatively movable with respect to the scale and whose detection state is switchable between a first detection state to read the first periodic pattern and output a first signal and a second detection state to read the second periodic pattern and output a second signal. A processor performs a first process to detect a first absolute position by using the first and second signals and then performs a second process to calculate a relative movement amount by using a specific signal that is one of the first and second signals and detect a second absolute position by using the relative movement amount and the first absolute position. The specific signal is obtained from the detector set in a same detection state as that set last in the first process. | 04-25-2013 |
20130126718 | OPTICAL ENCODER AND APPARATUS INCLUDING THE SAME - The optical encoder includes a scale provided with a periodic pattern in which an optical portion is periodically formed with a first period in a first direction, and a light receiver movable relatively with the scale in the first direction and photoelectrically converts a detection light from a light source and then passing through the optical portions. The optical portion periodically has a pattern, which is formed by pattern portions mutually adjacent in a second direction orthogonal to the first direction and mutually shifted in the first direction, in the second direction with a second period of t. A width w of the light source in the second direction satisfies w=(a+b)/b·nt where n represents a natural number, and a:b represents a ratio of a distance from the light source to the periodic pattern and a distance from the periodic pattern to the light receiver. | 05-23-2013 |
20130163654 | ENCODER - An encoder ( | 06-27-2013 |
20130292556 | ENCODER AND APPARATUS USING THE SAME - The encoder includes a scale having a first periodic pattern and a second periodic pattern, a sensor relatively movable with the scale. The sensor outputs in a first detection state a first periodic signal changing with a change period corresponding to the first periodic pattern and outputs in a second detection state a second periodic signal changing with a longer change period corresponding to the second periodic pattern than that of the first periodic signal. A processor calculates a position in a relative movement direction of the scale and sensor by using both the first and second periodic signals. The processor takes in the second periodic signal, the first periodic signal and the second periodic signal in this order at mutually different times, calculates phases of the second, first and second periodic signals at a specific time and calculates the position at the specific time by using the calculated phases. | 11-07-2013 |
20130292557 | ENCODER AND APPARATUS USING THE SAME - The encoder includes a scale provided with first and second tracks, a sensor relatively movable with the scale and reading periodic patterns to output periodic signals, and a processor calculating a position in a relative movement direction of the scale and sensor by using the periodic signals. The first track includes first and second periodic patterns whose periods are mutually different, and the second track includes a third periodic pattern whose period is different from that of the second pattern and is an integral multiple or an integral fraction of that of the first periodic pattern. The processor calculates, by using a phase difference between the periodic signals corresponding to the first and third periodic patterns, the position in which a sensor reading error due to a relative displacement between the first and second tracks and the sensor is corrected. | 11-07-2013 |
20140277730 | POSITION DETECTION APPARATUS, LENS APPARATUS, IMAGE PICKUP SYSTEM, AND MACHINE TOOL APPARATUS - A position detection apparatus ( | 09-18-2014 |