Abstract: A magnetic disc recording and/or reproducing apparatus in which a magnetic disc cassette containing a magnetic disc provided with a center hub is loaded so that the center hub engages with a rotary shaft of a disc rotating motor to rotate the magnetic disc. A cam for displacing a magnetic head is fitted to the outer periphery of a boss supporting a bearing which supports rotatably the rotary shaft, so that the force from the cam can be transmitted to the magnetic head through a bearing utilizing the rotational movement having a high transmission efficiency. As a result, a pulse motor for displacing the magnetic head can be made compact in size and light in weight and the power consumption of the pulse motor can be reduced. The cam is interposed between the level of the magnetic head and the chassis and the rotary shaft of the disc rotating motor is used also as the rotation center for the cam via a bearing mechanism, so that the magnetic head can access any position.

Abstract: A magnetic disc recording and/or reproducing apparatus in which a magnetic disc cassette containing a magnetic disc provided with a center hub is loaded so that the center hub engages with a rotary shaft of a disc rotating motor supported on a U-shaped chassis to rotate the magnetic disc.

Abstract: A magnetic disc recording and/or reproducing apparatus in which a magnetic disc cassette containing a magnetic disc provided with a center hub is loaded so that the center hub engages with a rotary shaft of a disc rotating motor to rotate the magnetic disc. A cam for displacing a magnetic head is fitted to the outer periphery of a boss supporting a bearing which supports rotatably the rotary shaft, so that the force from the cam can be transmitted to the magnetic head through a bearing utilizing the rotational movement having a high transmission efficiency. As a result, a pulse motor for displacing the magnetic head can be made compact in size and light in weight and the power consumption of the pulse motor can be reduced. The cam is interposed between the level of the magnetic head and the chassis and the rotary shaft of the disc rotating motor is used also as the rotation center for the cam via a bearing mechanism, so that the magnetic head can access any position.

Abstract: A magnetic disc recording and/or reproducing apparatus in which a magnetic disc cassette containing a magnetic disc provided with a center hub is loaded so that the center hub engages with a rotary shaft of a disc rotating motor to rotate the magnetic disc. A cam for displacing a magnetic head is fitted to the outer periphery of a boss supporting a bearing which supports rotatably the rotary shaft, so that the force from the cam can be transmitted to the magnetic head through a bearing utilizing the rotational movement having a high transmission efficiency. As a result, a pulse motor for displacing the magnetic head can be made compact in size and light in weight and the power consumption of the pulse motor can be reduced. The cam is interposed between the level of the magnetic head and the chassis and the rotary shaft of the disc rotating motor is used also as the rotation center for the cam via a bearing mechanism, so that the magnetic head can access any position.

Abstract: A recording and/or reproducing apparatus for recording on and/or reproducing from a recording medium. The apparatus includes a head supported by a head mount movable in the radial direction of the recording medium and a head positioning member for displacing the head mount to position the head with respect to the recording medium. The head positioning member includes a shaft for rotating the recording medium about its axis of rotation and a cam which is rotatable about the shaft, the axis of rotation of the cam and recording medium being coincident and the rotation of the shaft being independent of the rotation of the cam. The cam is made of a material having a coefficient of thermal expansion substantially equal to that of the material of the recording medium.

Abstract: There is provided a small printer capable of effecting printing in two colors by a simple structure. The small printer comprises a base formed in a cylindrical shape, a plurality of places of printing type belts mounted on the outer peripheral surface of the base, two sets of printing type groups of the same pattern formed on the printing type belts circumferentially thereof, hammer units corresponding to the printing type belts and contained in the base, and a pair of ink rollers capable of applying inks of distinct colors to the different printing type groups formed on the printing type belts.

Abstract: Improvement in the printing device of a type ring selection system, wherein each independent type ring for each numerical place is rotationally controlled to select a required type on the outer periphery of each type ring at a position opposite to a platen, whereby the types for these numerical places to be printed in one line are aligned and the single line is printed at once with the thus aligned types.

Abstract: A printing device includes a wire printing head provided with a plurality of closely adjacent printing wires movable back and forth with respect to a web of printing paper with inking ribbon interposed therebetween. The device further includes a pair of spools for taking up the inking ribbon and a carriage for supporting thereon these spools and the printing head in an associated relationship. The carriage may be moved along a print line in a first direction by first drive means, and in a second direction opposite to the first direction by second drive means. Means is provided to rotatively drive said spools on the carriage in response to the movement of the carriage imparted by the first drive means. The shift of the carriage from the first direction to the second direction may be provided by an automatic reversing mechanism. The rotation of the spools on the carriage may be stopped by stop means when the carriage is being moved by the second drive means.

Abstract: An ink roller cartridge having an ink roller rotatably mounted therewithin is formed with an opening through which the ink roller is engageable with a printing type drum when the cartridge is mounted on a printer body. The cartridge is provided with a lid to close the opening. A knob is provided on the outer periphery of the ink roller cartridge to facilitate the mounting and dismounting of the cartridge.

Abstract: As a scanning element of an electrophotographic copying machine begins to move, a feed roller moves a sheet of copy paper into the bite of register rollers which are held stationary. This movement of the copy paper is accomplished in a period of time which is less than that required for the scanning element to reach a predetermined scan synchronizing point. The feed roller is then stopped so that the copy paper is slightly buckled and thereby resiliently urged into the bite of the register rollers. When the scanning element reaches the scan synchronizing point, a sensor causes the register rollers to rotate thereby feeding the copy sheet through the machine in synchronization with the movement of the scanning element. The copy machine may employ a seamless photoconductive drum or belt moving at constant speed in which case an electrostatic image is formed on the drum or belt by the scanning element. The image is developed by toner particles and transferred to the copy sheet.

Abstract: A device for imparting back tension of a predetermined magnitude to the portion of strip material disposed between a take-up reel and a supply reel when the strip material wound at one end on the supply reel and at the other end on the take-up reel is paid out of the supply reel by rotating the take-up reel. The device has particular utility in an electrophotographic copying apparatus employing a photosensitive drum in which a strip of photoconductive film is interchangeably mounted and comprises a novel mechanism, light in weight and low in cost, which has the effect of imparting to the strip back tension which it is required to have when in use and yet enabling the strip to be advanced and wound on the take-up reel with the exercise of a force slightly in excess of the back tension present in the strip.

Abstract: To adjust the density of alphanumeric to be thermally printed by a thermal printer, a time duration for applying the row or column drive current to the selected dot elements in a thermal head is varied so as to vary a time duration for which the selected dot elements are energized, to thereby change the quantity of heat dissipated therefrom depending upon the environmental temperature, the thermal characteristics and aging of thermally sensitive paper and so forth. The drive current flowing duration may be varied by varying a cycle of the drive current signals to be sequentially applied to the row or column drive lines of a dot element matrix circuit through a character generator. In one embodiment of the present invention, the cycle of the drive current signals may be varied by the frequency division or count down of the clock pulses with a variable pulse repetitive rate used in an electronic computer.