Abstract: An optoelectronic incremental measuring system for measuring lengths or angles comprises a scale member provided with an incremental scale and a scanning unit, which is adjustable along the scale and comprises scanning grids, which are spaced apart by an integral multiple and a fractional part of a scale increment, a plurality of optoelectronic receivers associated with respective ones of such grids, and a plurality of light-emitting diodes, which are associated with the respective grids and adapted to illuminate the associated receiver via the scale and the associated scanning grid. In such a system a movement of the scanning unit and the scale relative to each other will cause the receivers to generate phase-displaced sine signals having periods in a number depending on the number of scale increments traversed by the scanning unit.

Abstract: A scanning unit comprises offset scanning gratings and light receivers disposed behind respective gratings. The scanning unit is moved past an incremental scale and the receivers are illuminated through the scale and the gratings. Carrier frequency signals which are displaced in phase and are amplitude-modulated in dependence on the pitch of the scale are generated in response to the scanning movement. The phase displacement of the modulation of the carrier signal is evaluated to determine the instantaneously scanned fraction of a scale increment in that a proportional number of clock pulses are counted by a counter. The use of a simple and reliable circuit arrangement and a reliable evaluation are permitted in that the illumination is modulated at the carrier frequency so that the light receivers constitute means for effecting an amplitude modulation of the carrier frequency signal. The amplitude-modulated signal is then processed further.

Abstract: A sealed instrument for measuring lengths comprises a carrier, a scale mounted on said carrier, and an optoelectronic scanning unit including a scanning plate, light emitters and light receivers. The scanning unit is adjustable along the scale by means of a feeler, which includes an actuating member. A correcting device is provided, which includes a deformable correcting template and a template follower for scanning the correcting template and for adjusting the scanning plate relative to the actuating member in the direction of the scanning movement. In order to reduce the overall expenditure, to simplify the correction and to increase the reliability of operation and the accuracy of the measurement, only the scanning plate is operatively connected by an adjusting mechanism to the template follower and is adjustable relative to the remaining parts of the scanning unit in dependence on the configuration of the correcting template.

Abstract: The scanning unit which is movable along the scale member comprises signal-generating means, which are accommodated in one or more covering hoods. Each covering hood has an annular boundary surface facing the scale member and is provided at said boundary surface with an annular seal which consists of elastomeric material and is in sealing contact with the scale member under initial compressive stress throughout the peripheral extent of the boundary surface. The covering hood and the scale member thus define between them a measuring chamber in which the atmospheric conditions are favorable for an accurate measurement. As the scanning unit is moved along the scale member, the measuring chamber will always be disposed at a portion of the scale member in which the surface of the scale member has just been cleaned by the sliding contact between the annular seal and the scale member.

Abstract: The incremental measuring and machine control system comprises an incremental scale and an auxiliary track extending beside said scale along the same and provided with at least one reference mark in register with a predetermined point of said scale. A scanning unit comprises scanning means for scanning said scale and for generating analog signals in response to the scanning of said scale. The scanning unit comprises additional scanning means for scanning said reference marks and for generating reference signals in response to the scanning of the reference marks. A processor derives digital signals for said analog signals and delivers the digital signals to a counting or display unit which is controlled by said reference signals or by signals derived therefrom.

Abstract: A linear measuring system comprises an elongate housing tube, which contains a metal strip, which is provided with a scale. The housing tube contains also a scanning unit, which is movable along the scanning tube to scan said scale. To ensure that the metal strip will be uniformly tensioned throughout its length and that the accuracy of the scanning operation will not be affected by a deviation of the longitudinal direction of the housing tube from a desired direction in which the measurement is to be taken or by changes of the length of the housing tube, the metal strip extends in the housing tube substantially without a longitudinal restraint and extends at both ends out of the housing tube and is held at said two ends by brackets, which are disconnected from the housing tube. In the housing tube, the side edges of the metal strip are entirely clear of the housing tube.

Abstract: The instrument for measuring lengths comprises a carrier, a rule secured to that carrier and provided with a scale, and an optoelectronic scanning unit comprising a scanning plate, light emitters and light receivers. The scanning unit is movable along the scale by means of an actuating member, which constitutes a feeler. Auxiliary tracks are provided for guiding the scanning unit along the scale. A part of the scanning unit is connected to the actuating member by means which are yieldable transversely to the longitudinal direction of the scale. Auxiliary tracks are provided for guiding a part of the scanning unit along the scale. The overall structure is simplified and reduced in overall size and a change of the clearance between the scanning plate and the rule is prevented in that only the scanning plate is guided in engagement with the auxiliary tracks, one of which is constituted by the rule.

Abstract: A hand-held measuring implement comprises a transparent scale-carrying member provided with a graduated scale. A reading unit is movable along said scale in unison with a feeler and comprises photoelectric receivers, which scan the graduated scale through respective line screens. The graduated scale is illuminated by light sources, which are disposed on the same side of the graduated scale as the receivers and are movable with the latter. Signal-processing circuitry is provided for processing the indicating signals generated by the receivers. The implement comprises also a display device and power supply means. To improve the light efficiency and to reduce the power consumption of the light sources and to reduce the effects of an ageing and soiling of the scale-carrying member, the latter is wider than the graduated scale and provided on the side opposite to the line screens with a reflecting covering.

Abstract: A scale assembly is provided with a scale which has a predetermined scale increment. The scale assembly consists of a plurality of scale sections, each of which is provided with a length portion of said scale and which are separated by joints having in the longitudinal direction of said scale a width that is smaller than a predetermined width. A measuring slide is movable along said scale and carries first and second photoelectric sensor means, which are spaced apart along said scale by a distance which exceeds said predetermined width. Each of said sensor means are adapted to be enabled and when enabled are adapted to photoelectrically scan said scale and to deliver a predetermined number of length signals in response to the movement of said slide along said scale to the extent of each of said increments. Integrating means are provided for integrating each of said length signals from each of said sensor means which are enabled.