Abstract: A chart recorder is disclosed having a variable chart speed and a writing device in the form of a variable droplet rate ink jet pen. The signal pulses for ejecting ink droplets from the pen are generated by a voltage controlled oscillator, and circuits are provided to make the oscillator output frequency proportional to the chart speed, and also responsive to higher rates of pen movement, so that a substantially uniform density line is traced at all chart speeds and virtually all rates of pen movement. To simplify the circuit while maintaining an extremely wide range of writing speeds, the voltage sweep range of the oscillator is set at the upper end of the pen response frequency, and lower oscillator output rates are established by selectable R-C circuit components to match the speed of the chart recorder. To give more precision, a circuit embodiment is also disclosed that generates pen control pulses proportional to the true rate of relative movement between the pen and the chart.

Abstract: An anti-smudge bar for a recorder is disclosed wherein the recorder has a drive means for advancing a strip chart in a longitudinal direction. The strip chart, as it advances, passes over a platen disposed upstream of the advancing means. A pressure roller adjacent the upstream side of the platen presses the strip against the platen. The pressure roller has a plurality of longitudinal grooves spaced by sharp crests which contact the chart in a manner preventing smudging of wet ink traces previously recorded on the chart. The ink traces are recorded on the chart by a recording pen which is movable in a direction transverse to the direction of chart movement. The roller and the pen are lifted from chart contact whenever the chart direction is reversed to permit subsequent recording on a chart segment previously recorded on.

Abstract: A paper transport system used in connection with a thermal analog recorder is provided. This system engages the paper for a predetermined length of time and subsequently releases it employing mechanical means. Roller means are provided for engaging and transporting a heat sensitive paper. When the test paper is inserted into the nip formed between the roller means, a tapered resistor element residing on at least one of the rollers is made to develop a non-uniform temperature profile when energized from the output of a test source which permanently marks or records on the test paper. An improved method of single channel thermal analog recording is also disclosed employing this device.

Abstract: A recording medium drive roller and a wrap roller are mounted to a cover for an electrographic printer and cooperate to enable the recording medium to be easily loaded into the printer when the cover is open, and to provide proper tension to the paper when the cover is closed to permit uniform and aligned feeding of the recording medium from the source during operation of the printer.

Abstract: A recording instrument for accompanying a cargo to record an environmental variable such as temperature, the housing of the instrument containing a removable chart pack with two spools and the chart pack being retained in the housing by two lugs located on a motor case in the housing lid. The battery circuit that drives the electric motor for the spools is activated by pulling an exposed non-conductive strip out from between two terminals.

Abstract: An apparatus for plotting information, e.g., seismic data, onto a continuous sheet of a recording medium, e.g., photographic film. The film travels from a supply reel, over an advance roller, across a flat exposure surface, and onto a takeup roller. Torque motors apply equal but opposite torques to the supply reel and the takeup reel to maintain the film in tension to insure that the film will lie flat on the exposure surface during the plotting operation. A stepping motor rotates advance roller to move the film a precise amount across the exposure surface at desired times during the plotting operation. A camera, e.g., cathode ray tube, which receives data and projects it onto the film on the exposure surface, is mounted on a carriage which is swept back and forth across the exposure surface by means of a lead screw driven by a precision stepping motor.

Abstract: In a measuring instrument such as a spectrophotometer which is driven under the control of a dedicated microcomputer and has a provision for wavelength scan, a flow chart lock system is obtained by storing in the random access memory of the microcomputer an indication of the actual chart position between two sprockets on the chart drive. With this information and stored data regarding the position of the scanning apparatus of the instrument, accurate repositioning of the chart to accurately reflect the scanning position even after scale changes or different modes of operation have occurred is accomplished.

Abstract: A portable medical data strip chart recorder in which a drive roller for drawing the strip across a platen includes integral motive means for rotating the roller at a selected angular velocity. A D.C. motor is mounted internally and concentrically with the roller shaft which upon energization drives the roller and hence the strip paper at a desired linear velocity. The incorporation of a D.C. motor internally of the drive shaft permits reduction in size and weight of the recorder as well as achieving a more efficient drive power transmission.

Abstract: A data recording instrument having a recording sheet supply roll and a recording sheet take-up roll used for continuously recording a sensor. The instrument utilizes an axially movable rod activated by pulsing means. Movement of the rod advances the take-up roll through lever means connected to the axially movable rod. The lever means adjusts the degree of turning of the take-up roll in proportion to the amount of recording sheet accumulated on the take-up roll. The axial movement of the rod also activates marking means for charting the resultant output of at least one continuous sensor.

Abstract: A device is provided for recording written information dealing with the care of a patient. Each additional entry advances the previous entry and records it as a permanent record on the same tape roll. Each earlier entry is thereby hidden from view, thus preventing the alteration of records.

Abstract: A recording device includes record means for recording information on a recording medium, a guide for feeding the recording medium to the record means, and means for moving the guide in accordance with the configuration of the recording medium.

Abstract: An apparatus for handling sheets of material of various lengths such as consecutive plots from a computer printout device. The apparatus is comprised of a housing adapted to be affixed to a source such as the output section of a computer printout device. A takeup roller is mounted in the housing and is adapted to receive the material as it is fed from the source. When all of the material of a particular sheet has been rolled, a means ejects the material off the roller. As the roll of material is ejected from the roller, a securing means, e.g., elastic band, is automatically applied to the material to secure it in a rolled condition.

Abstract: A graphic recorder for use in recording information on a strip chart. The recorder includes a housing having a pair of rollers mounted at opposite ends of an opening across which the strip chart moves. Radially outwardly extending pins are mounted at opposite ends of each of the rollers for registering with and engaging positioning holes formed along the edges of the strip chart. Drive apparatus is provided for reversibly turning the rollers conjointly to move the strip chart along an X-axis. Apparatus is provided for creating a partial vacuum in a chamber within the housing so as to tension the portion of the strip chart suspended between the rollers along a curved path for properly positioning the chart with respect to the pins on the rollers. A recording head is mounted on the cover of the housing for movement along a Y-axis for marking the strip chart.

Abstract: The invention relates to a tracing apparatus operating automatically on the basis of digital imputs.A buffer-loop is formed in the paper band between each drive roll and the control drum, and the loops so formed are balanced by a loop corrector/reader device. In one prior art apparatus, this device includes photoelectric cells.The tracing apparatus is characterized in that it includes three suction chambers, one for each buffer-loop and a third central chamber beneath the control drum, whereby two saggings of the paper are obtained on either side of the control drum that are entirely independent of the two buffer-loops.

Abstract: An improved chart carrier for a recorder permitting use with a take-up spool for relatively long periods of time, and without the take-up spool for shorter periods of time, a cylindrical enclosure being employed for rolling and enclosedly retaining the used portion of the chart in a predetermined portion of the chart carrier.