摘要:
An electronic level includes a conductive gravity-levelled reference element (33) and one or more pairs of sensing electrode members (A1-D1) supported in spaced confronting relation to the reference element on a flat rigid support (37) which is movable relative to the reference element. A dielectric fluid separates the reference element (2) from the sensing electrode members so that at least one pair of capacitors is formed the capacitances of which capacitors vary oppositely in response to deviation from level position of a line joining the pair of sensing electrode members and the consequent loss of parallelism of that line with the reference element. Alternating voltages are applied to the capacitors such that the product of the capacitance and the applied voltage is equal for both capacitors when parallelism exists. A detecting means senses variations of the capacitances and provides an indication of any deviation from level position of the flat support (37). The detecting means comprises an inverting amplifier including a feed-back capacitor formed by the reference element (33) and an additional electrode member (E1) disposed symmetrically with respect to the sensing electrode members (A1-D1) on the support (37).
摘要:
An electronic distance meter which makes a distance measurement by phase comparison between measuring signals modulated on an emitted light beam and on a received light beam reflected from a target is provided with a microphone, an amplifier and an extra modulation circuit, which modulates audible information on the measuring signal of the distance meter. A receiver provided with a detector sensible for the optical wavelength region of the emitted light beam is mounted at a reflecting prism mounted at the target. The receiver at the prism is provided with circuits for detecting the audible information modulated on the measuring signal and a loud speaker or an ear phone. At a receiver of the distance meter the audible information is filtered out from the received measuring signal before distance calculation is made by internal circuits of the instrument.
摘要:
A ventilator intended for placing in an outer wall has a double-acting axial-flow fan with an inner and an outer impeller blade ring disposed such that the blade rings are each in register with a coaxial channel in a duct placed in a through-opening in the wall. A reversing means is connected to the impeller motor for changing the direction of rotation thereof so that it alternatingly rotates in one or the other direction. A regenerator means is inserted in the channels, the means both absorbing heat and distributing moisture within itself.
摘要:
An accelerometer is provided which comprises a pendulum rotatable about an axis and which is arranged for measuring vertical angles. A rotatable device which is preferably of the moving coil type is located at the axis of rotation of the pendulum. The rotational device preferably comprises magnet arrangement for providing a constant magnetic field, and a movable coil which supports the pendulum for rotation and is rotatable in the magnetic field. The angle to be determined is measured by rotating the magnet arrangement about the axis from a reference position to the desired angular position and thereafter supplying current through the coil of such strength and polarity that the coil, and thus the pendulum is rotated about the axis of rotation from the vertical reference position it would normally assume due to the forces of gravity to the angular position of the magnet arrangement. The current required to effect such rotation of the pendulum is proportional to the angle to be measured.
摘要:
The present invention relates to an arrangement for coaction with a distance measuring instrument in the setting out of boundaries or like demarcations. The distance measuring instrument includes an electronic distance meter, a vertical angle meter (18) and a horizontal angle meter (19), a signal processing and computer unit (16, 16') which computes the position of a measuring reflector (12) in relation to the instrument, and an input means (17) for input of desired setting-out data for an area of land into a memory location in the computer prior to a setting-out operation. The distance measuring instrument is held directed towards the measuring reflector and repeatedly makes measurements thereon. With each measuring occasion, the computer unit (16) ascertains whether or not the data obtained lies within a predetermined, acceptable tolerance range in relation to the setting-out data. If the measured data lies outside this range, the computer establishes how the reflector should be moved in order to be located within the tolerance range. An indicator is controlled by the movement signals produced by the computer unit and in response to these signals continuously gives to a person positioned adjacent the reflector a clear, discernible indication of whether the reflector shall be moved, and if so, in which direction or directions, or if the reflector should be left as it is.
摘要:
A method and an apparatus of obtaining measurement data from a chemical process in a mass in a space, such as the charge in a blast furnace, is disclosed where the mass passes through the space from an inlet to an outlet and chemical and/or mechanical change in the mass takes place as it passes through the process. Sensors implemented as individual, unconnected units are mixed into the mass at the inlet, each sensor being equipped with a transmitter of acoustic or electromagnetic type, and with one or more sensing means connected to the transmitter for sensing the properties to be measured. The transmitter sends signals with information on the properties detected by the sensing means. Reception means for taking up acoustic or electromagnetic signals are placed outside the space with spreadout placing over the defining surface of the space. The position of the sensors inside the space is calculated with guidance from a property such as signal strength, time position, field direction or the like, of the signals sent by the different sensors and received wirelessly by said reception means. The properties of the surroundings measured by the sensing means of the sensors are finally presented for each sensor as measurement data for the calculated position of the sensor.
摘要:
A distance measuring instrument is provided for simple fieldwise mapping of an area. The instrument comprises an electronic distance meter, a unit for determining a vertical angle for aligning the instrument with a measuring point, and a unit for obtaining a horizontal angle for the alignment of the instrument with a measuring point. The horizontal angle unit comprises a terrestrial magnetic-field detector which comprises at least two detector units fixedly mounted in the instrument. The units are directed in mutually different directions so that at least two components of the magnetic flux in an instrument-based coordinate system are obtained by the units. A calculating unit is arranged to convert the coordinates of the components of the terrestrial magnetic field from the instrument-based coordinate system to an earth-based coordinate system. The vertical angle obtained from the vertical angle unit is used for this conversion. The calculating unit is arranged to calculate the direction of the terrestrial magnetic field in a horizontal plane and determine the horizontal angle relative to a reference direction.
摘要:
The invention relates to an arrangement for measuring wheel alignment and steering geometry in an automobile. A substantially horizontal bar is placed in front of the vehicle at right angles to its longitudinal axis. A light source displaceable along the bar emits a narrow ray of light at an angle to the bar. The vehicle front wheel to be measured is provided with a unit including at least three angle sensors of which at least one comprises a widely dimensioned light detector placed in the focal plane of an optical means. The light source on the bar is set to a position on said bar where the emitted light beam strikes the optics approximately at the center thereof. A calculating device determines the wheel alignment values with the aid of the angle sensor signals for variable positions of the wheel and the motion of the light source along the bar.
摘要:
An arrangement for measuring dimensions and/or checking the dimensional accuracy of large objects (1), such as car bodies or the like. The arrangement comprises a straight movement path (8) and one or a plurality of transmission units (10) movable along the path. During indication of each checking point which may comprise a bolt head, a suspended measuring rod (2-7) or the like, two measuring light beams are projected onto the point concerned from two different directions. When the light beams are projected, two are predetermined and one a variable of the following components: the distance between the starting positions for the first and the second light beam, the angular position between the first light beam and a line drawn between the starting positions and the angular position between the second light beam and said line. It is first ensured by movement of a transmission unit (10) that one of the light beams with a fixed angular relationship to the movement path impinges on the checking point or on a point at which, according to data for the object, the checking point should lie and subsequently the variable component is altered with a controllable control unit (11) so that the second measuring light beam also impinges on the checking point or on a point at which the checking point should lie according to data for the object.
摘要:
A method and apparatus are provided for balancing out interference caused by stray coupling between the internal circuits of a distance measuring apparatus of the phase-type in a simple manner which produces a substantial increase of the usable measuring range. At least two groups of mutually separate distance measurements are performed, with each group including at least one measurement operation. For each pair of groups of distance measurements, one measuring group is effected with the transmitter signal in a first phase and the other measuring group is effected with the transmitter unit of the transmitter section supplied with a transmitter signal in a second phase which is displaced substantially 180.degree. relative to the first phase. The mean value or the mean values of the measuring results in each measurement group are thereafter formed, with this calculation being made either by hand or automatically. Preferably, the invention includes a controllable phase shifter to provide the phase shift of the measurement signals supplied to the transmitter.