Tokyo Kogaku Kikai Kabushiki Kaisha

Tokyo Shibaura Denki Kabushiki Kaisha

Tokyo Kagaku Kikai K.k.

Tsuneo Sasaki

Fumio Ohtomo

Takashi Yokokura

Fumitomo Kondo

Kazuaki Kimura

Masana Minami

Hiroshi Tamaki

Masayuki Kondo

A displacement measuring device, using an incremental code, which includes a coding member (22) resting on the object (21) to be measured and having a coding section for generating such signals that a sensing element can discriminate the signals as 0 or 1, sensing means (25A, 25B) disposed to sense the coding section of the coding member for producing sensed signals in response to the displacement of the coding member (22), and rectangular wave-converting circuits (27A, 27B) for receiving and converting the sensed signal into rectangular wave signals. A clock pulse generator (28) is provided in the device for generating a clock pulse with a higher repetition-frequency than the repetition-frequency of the sensed signal. An edge detector (29) receives the clock pulse from the clock pulse generator (28) and the rectangular wave-signal from the rectangular wave-converting circuits (27A, 27B) and then delivers, as an output pulse, the clock pulse substantially coincident with at least one of the leading edge and the trailing edge of the rectangular wave-signal. A counter (30) counts the output pulses from the edge detector and a display (31) indicates the counted value. With such an arrangement, an incremental displacement measurement can be made without a differentiating circuit and an averaging circuit.

Displacement measuring device utilizing an incremental code

A displacement measuring device, using an incremental code, which includes a coding member (22) resting on the object (21) to be measured and having a coding section for generating such signals that a sensing element can discriminate the signals as 0 or 1, sensing means (25A, 25B) disposed to sense the coding section of the coding member for producing sensed signal in response to the displacement of the coding member (22), and rectangular wave-converting circuits (27A, 27B) for receiving and converting the sensed signal into rectangular wave signals. A clock pulse generator (28) is provided in the device for generating a clock pulse with a higher repetition-frequency than the repetition-frequency of the sensed signal. An edge detector (29) receives the clock pulse from the clock pulse generator (28) and the rectangular wave-signal from the rectangular wave-converting circuits (27A, 27B) and then delivers, as an output pulse, the clock pulse substantially coincident with at least one of the leading edge and the trailing edge of the rectangular wave-signal. A counter (30) counts the output pulses from the edge detector and a display (31) indicates the counted value. With such an arrangement, an incremental displacement measurement can be made without a differentiating circuit and an averaging circuit.

An encoder for measuring devices having a code plate including binary grating patterns arranged in a given regular fashion and forming a first scale, a linear sensor including photodiode elements arranged with fixed intervals and forming a second scale disposed in parallel with the code plate, and processor means for absolute-interpolating one pitch of the first or second scale on the basis of reading data or information obtained from the linear sensor corresponding to a relative position of the patterns to the elements. When the number of the scale divisions of the first scale within a fixed range is N, the number of the scale divisions of the second scale is N+1. Accordingly, when the first scale is a main scale, the second scale is a vernier scale. The processor means detects a phase inverting point corresponding to the interpolation point on the basis of the reading data. The processor means performs the absolute interpolation by detecting the phase inverting point.

Encoder for length or angle measuring device with high accuracy

An encoder having an optical measuring part establishing a vernier relationship between a code plate and a line sensor, and counters for obtaining a course reading from time serial output signals of the line sensor and a fine reading from the vernier relationship. Correction data including a change component in a magnification of a lens system are obtained from a counter. The correction data and the fine reading are supplied to a converting circuit to provide a corrected fine reading.

Growing community of inventors

Tokyo, Japan

Tsuneo Sasaki