Abstract: A position control system in a copying apparatus keeps an original positioned properly during multiple passes of the original through a transport path, for making multiple copies, by detecting the position of an edge of the original in the first pass, when the original is fed into the apparatus; setting a reference condition corresponding to the then existent side edge position; and in each subsequent pass of the original detecting its position and in the event of a deviation of the detected position from the position represented by the reference condition activating a position correcting device to displace the original to the latter position.

Abstract: Methods and apparatuses for electrically investigating a borehole are described. Tool mounted pads are provided, each with a plurality of small measure electrodes from which individually measurable survey currents are injected toward the wall of the borehole. The measure electrodes are arranged in an array in which the measure electrodes are so placed at intervals along at least a circumferential direction (about the borehole axis) as to inject survey currents into the borehole wall segments which overlap with each other to a predetermined extent as the tool is moved along the borehole. The measure electrodes are made small to enable a detailed electrical investigation over a circumferentially contiguous segment of the borehole so as to obtain indications of the stratigraphy of the formation near the borehole wall as well as fractures and their orientations.

Abstract: Disclosed is an overload protection apparatus for variable pitch propellers, particularly cycloidal propellers. The apparatus is of the kind having a hydraulic servomotor (2) with an adjustment rod (1) for actuating a propeller, and having mechanical restoration means comprising an auxilliary adjustment means for adjusting a restoring lever (5) via an intermediate lever (6). As disclosed, the restoring lever (5) is pivotally linked to a first arm of the intermediate lever (6) which in turn is pivotally mounted on said adjustment rod (1) at a fulcrum (9). The first and second arms of the intermediate lever extend from opposite sides of the fulcrum. The second arm of the intermediate lever preferably includes a slideway (15) which receives a slide-shoe (16) affixed to an auxilliary adjustment lever (7), which is preferably an angular lever on which the auxilliary adjustment means acts at the end (12).

Abstract: A nuclear radiation attenuator for providing a test image from a source of radiation is disclosed. The attenuator provides a test image including a plurality of discrete target images located in a background image. Each target image has an intensity that differs from the intensity background image to provide a target to background contrast ratio for each target image. A plurality of the target images each have a different contrast ratio so that the contrast ratios of the target simulate contrast ratios found in clinical testing. The attenuator provides a standardized test image that enables the performance of a scintillation camera to be tested routinely.

Abstract: A game board device includes a game board having playing spaces arranged in a regular rectangular array of rows and columns, playing pieces divided into three sets or groups, each set or group of which is of a characteristic distinguishable from the other, the number of playing pieces of one of the sets, a "neutral" set, being equal to the number of playing spaces, while the number of playing pieces of each of the other sets, the "assigned" sets, are equal to each other and, respectively, to one-half the number of playing spaces. The distinguishable characteristics may be different colors, or different shapes although the characteristics lend themselves to many variations including being representative of themes to make the game more appealable to players of certain age groups.

Abstract: A method and apparatus for improving the efficiency of a heat generator in which combustible fuels such as fossil fuels, refuse, or other materials are burned is described. Flue gas generated in the heat generator and combustion air are passed in heat exchange relationship in a heat exchanger. The heat exchanger is selected so that it removes a substantial amount of heat from the flue gas, whose temperature is consequently lowered to a level where a corrosive pollutant such as SO.sub.3 in the form of H.sub.2 SO.sub.4 is likely to condense out. A pollutant removing liquid is applied onto the portion of the heat exchanger where the flue gas passes through both to scrub the flue gas and protect that portion of the heat exchanger from corrosive effects from condensed pollutants.

Abstract: A web severing apparatus is described which is operative between support rollers and a web wind-up roll employed in a web winding machine. The web severing apparatus consists of a retractable beam which is guided on axial ends of the support rollers. The beam has at its upper end a pivotably arranged mounting on which a web tear-off blade is screwed. The mounting further supports at a small distance away from the web tearing blade, a web holding element having a web contacting surface to clamp the web firmly on the roller when the web tear-off blade is so positioned relative to the web contacting surface that a narrow gap is formed between the web tearing edge of the blade and the web. When the web wind-up roll is then pushed out over one of the support rollers, the web is pulled against the web tear-off blade and is severed. With such web severing apparatus, the surface of the support roller opposite the blade and the web tear blade are protected from damage.

Abstract: Vibrations in a taut flight of a photoconductive belt moving through the image projection zone or another processing zone of an electrostatic copying machine are suppressed by means of a closed flat plate surface disposed parallel to the belt flight at a small distance therefrom, such as a distance of 1 to 2 millimeters.

Abstract: A broad bandwidth segmented acoustic transmitter is described formed of a plurality of differently sized, closely spaced acoustically active and separately energizable segments. Each segment is operated at a separate resonance to provide, with the acoustic energy from the other segments, a broad frequency spectrum composite acoustic pulse. In one embodiment the segments are aligned along a common axis with their respective lengths, as measured along this axis, selected to provide an acoustic pulse with broad bandwidth. The segments are energized by a common pulse to provide an acoustic spectrum which improves the measurement of acoustic parameters such as the compressional and shear wave interval travel times.

Abstract: Silicate-based composition particles are rapidly and completely expanded to form an expanded, cellular particulate aggregate of maximum density in short periods of time at particle temperatures which are comparatively low, that is, 100.degree. C., compared to existing systems by the utilization of infrared heat sources, either gas or electric, to heat the silicate particles. The use of infrared energy operates in a surprisingly advantageous fashion when the expansion process is carried out on or in the presence of a surface having the capacity to act as a thermal mirror or absorber-reflector of the infrared radiation to make maximum utilization of the radiant energy by the creation of a radiation trap. Carbonaceous materials are preferred for producing such entrapment. A further significant aspect is the discovery of a time-radiation dependency.

Abstract: An apparatus is described for acoustically investigating a casing in a borehole with a source of acoustic energy that is directed at the reflecting surface of an acoustic reflector in front of which is an acoustically transparent window. The inclination of the window relative to the reflecting surface is selected to deflect secondary transmissions and thus reduce window produced interferences. Several embodiments are described.

Abstract: A method and apparatus are described for detecting the presence of an anomaly, such as the Groningen effect, whereby an error in a resistivity measurement of an earth formation layer is noted when such layer is located below a highly resistive bed. The resistivity is measured with a resistivity measuring sonde with the aid of a reference electrode located between the sonde and a conductive sheath around the cable from which the sonde is suspended in a borehole. A phase sensitive signal is measured and used to detect the presence of an error. In one embodiment, the out-of-phase potential of an electrode is recorded alongside a resistivity measurement as a function of depth. In another embodiment, the out-of-phase potential deviation from a normal value is determined and used to derive a corresponding in-phase potential deviation from which a measurement of the magnitude of the error in the resistivity measurement is made. Other embodiments are shown and described.

Abstract: A percussion technique is described with which an impulse is applied to an element to bounce it off the inner surface of a casing cemented in a borehole. The movement of the element is automatically measured to produce information from which the bond between the casing and cement behind the point of impact of the element can be evaluated. In accordance with one embodiment, the cement bond evaluation is automatically derived by comparing impact and rebound velocities of the element such as by generating a coefficient of restitution of the bouncing element. In another embodiment, the contact time of the element with the casing is measured to derive an indication of the quality of the cement bond.

Abstract: Techniques for a broad band high frequency acoustic investigation of a subsurface formation around a borehole are described utilizing a range of acoustic frequencies selected to produce detectable acoustic backscatter from grains within the subsurface formation. The acoustic backscatter is detected and a spectrum thereof is produced and averaged over adjacent subsurface formation regions. A subsurface formation parameter such as the frequency dependency of the attenuation of the backscatter is determined from an analysis of the spectrum to provide an indication of the granularity property of the subsurface formation. Use of a broad range of frequencies enables a determination of the subsurface formation parameter over a large range of grain sizes. In another technique the spectrum of the detected backscatter is modified to remove the effect of the frequency response of the system with which the investigation is made.

Abstract: A rear view mirror for vehicles is provided on a mirror housing having a remotely controllable motorized driving unit mounted inside it for turning the housing to adjust the mirror viewing range, yet enabling displacement of the housing without effect from or to the driving unit. A gear casing having an electric motor mounted on it contains speed reducing gears, is supported on and turnable about a mirror supporting post protruding from the housing, and is fixed to the housing to position the housing by movement about the axis of a ring gear that normally is held fixed relative to the post. The ring gear is connected with the post via a spring biased clutch that slips to enable forcible turning of the housing by hand or in the event of impact with an obstruction.

Abstract: Methods and apparatuses for acoustically investigating a casing in a borehole to derive the quality of a cement bond behind the casing and casing thickness are described. The techniques employ an acoustic pulse source having a frequency spectrum selected to stimulate a selected radial segment of the casing into a thickness resonance. The selected frequency spectrum enhances the reverberations between the inner and outer walls of the casing which traps the thickness reverberations with significant amplitudes for a duration depending upon the amount of acoustic energy leaked into adjacent media. The acoustic pulse causes acoustic returns which are formed by the reflections from interfaces between media of different acoustic impedances and acoustic energy leaked into the bore of the casing from the acoustic thickness reverberations stimulated within the casing walls. The acoustic returns are detected to generate a reflection signal which is processed to determine casing thickness or to evaluate the cement bond.

Abstract: An improved ball joint structure for clamping a rear view mirror head tightly yet turnably on a supporting ball member includes a ball seat member and a body clamping member fixed at the outer and inner sides of housing wall portions bordering an opening in which a mirror supporting ball is disposed, a ball clamping member mounted on the body clamping member and having a contoured portion to grip the inner side of the ball, and means adjustable from outside the wall for holding the ball clamping member under a desired tension against the ball. The body and ball clamping members have coacting formations that limit displacement of the ball clamping member in the direction away from the ball.

Abstract: A predetermined signal is removed from waveforms generated in an acoustic investigation of a borehole to enable the accurate detection of relatively weak formation signals. A plurality of waveforms are produced from different sonic receivers used in an acoustic investigation of an earth formation from inside casing set in a borehole. The waveforms include a casing signal which is representative of the acoustic casing wave which traveled from a transmitter through the casing to the receivers. The casing signal is removed by aligning the waveforms in accordance with the known travel times for the casing wave from the transmitter to the receivers and summing the waveforms to produce a casing signal emphasized waveform. A portion of the latter is then subtracted from the waveforms from which the casing signal is thus effectively filtered to facilitate detection and analysis of formation signals present in the waveforms.