Abstract: An automatic disc player including a housing, disc carrier means to convey a disc between predetermined playback position and a predetermined withdrawal position ready to be withdrawn out of the housing upon termination of plaback operation, signal generating means for producing control signals to be predominant over various steps of the playback operation, and an electric control circuit responsive to the control signals to control the various steps of the playback operation, the signal generating means comprising position detecting means responsive to movement of the disc to the withdrawal position and operative to produce a signal when the disc being moved away from the playback position reaches the withdrawal position, and playback re-start switch means which is operative to produce a signal in response to slight movement of the disc from the withdrawal position toward the playback position, the control signals to be produced by the signal generating means including signals to control the start of playbac

Abstract: A pulse-width modulation drive circuit for a load such as a motor, particularly, a motor used in a compact disc player or the like, in which losses in diodes used to absorb reverse EMF are substantially eliminated. For this purpose, the pulse widths of pulse signals used to on-off control drive current flow through the load are controlled so as to eliminate the diode losses. The circuits of the various embodiments of the invention are designed so as to be easily implemented in integrated circuit form.

Abstract: Disclosed is a polyester vessel having mouth, side wall and bottom portions formed of a polyester composed mainly of ethylene terephthalate units, wherein the thermoplastic polyester is a polyester containing a catalyst residue in an amount smaller than 1000 ppm as the metal, and in the thermoplastic polyester constituting the bottom portion of the vessel, the ratio of the thermal crystallization degree represented by the following formula:100.times.(Q.sub.DC -Q.sub.AC)/Q.sub.DC (1)wherein Q.sub.AC stands for the heat quantity of crystallization at elevation of the temperature and Q.sub.DC stands for the heat quantity of crystallization at lowering of the temperature, is lower than 90%.

Abstract: An NMR imaging apparatus of the present invention which is provided with an improved data acquiring means 16 and which is useful for enhancement of the speed of reconstruction of an image in NMR imaging by a multislice multiecho method is characterized in that a raw data memory 18 which is provided for storing raw data for the maximum number of slices that can be acquired in one scanning separately from the memory 10 of a computer system 6, and an address converter 19 for converting the addressses of the measured data supplied subsequently in accordance with the sequence of the multislice multiecho method and for storing the measured data in the raw data memory 18 in the arrangement different from the order of acquisition are disposed in a data acquiring device, so that a data block for each slice is formed in the raw data memory 18.

Abstract: A display method in a computer tomographic apparatus is disclosed wherein a plurality of bar graphs representing the scanning schedule are generated on a display. The bar graph depicts the scanning time extending one distance and the margin time extending a second distance at a smaller width. When the scanning is taking place, signals are generated to plot over the scanning bar graph during the scanning time and plot over the margin bar graph during the margin time. The scanning time and margin time bar graphs adjoin one another and are distinguishable by the margin time extending from the scanning bar at a narrower width. This configuration allows an operator to readily determine at a glance the scanning step and progress thereof.

Abstract: An automatic disc player including a housing, disc carrier means to convey a disc between predetermined playback position and a predetermined withdrawal position ready to be withdrawn out of the housing upon termination of playback operation, signal generating means for producing control signals to be predominant over various steps of the playback operation, and an electric control circuit responsive to the control signals to control the various steps of the playback operation, the signal generating means comprising position detecting means responsive to movement of the disc to the withdrawal position and operative to produce a signal when the disc being moved away from the playback position reaches the withdrawal position, and playback re-start switch means which is operative to produce a signal in response to slight movement of the disc from the withdrawal position toward the playback position, the control signals to be produced by the signal generating means including signals to control the start of playba

Abstract: In measuring a number of echo signal, which normally attenuate chronologically, in a single pulse sequence, such as in multi-echo method or a multi-slice method, each echo signal is received and suitably amplified by a reception amplifier having predetermined levels of gain for different time periods during which the successive echo signals are processed such that the echo signals received at a data collection unit are all of substantially the same amplitude regardless of where they appear in the time sequence. The predetermined levels of gains are obtained by false scanning prior to actual image scanning and calculation and storing in a memory. As a result, the echo signals can be received within a dynamic range which is smaller than using the conventional system.

Abstract: A percussion drill comprises an open-ended, hollow cylinder having an air exhaust hole on the side wall thereof, a piston mounted in the rear end portion of the cylinder, and a slide shaft mounted in the front end portion of the cylinder. A drill bit is releasably attached to the forward end of the slide shaft for working with a material. Between the piston and the slide shaft is mounted a striker which forms a forward variable volume air chamber and a rearward variable volume air chamber. The piston is driven by a motor-crankshaft arrangement to reciprocate axially in the cylinder to cause a positive high pressure to develop in the rearward chamber, which pressure provides an impact on the striker whose mechanical energy is transferred to the slide shaft. A return movement of the piston develops a negative pressure in the rearward chamber to pull back the striker to the impact position.