Abstract: A magnetic disc drive in which two magnetic heads, each of which has at least two magnetic gaps, are provided on a single carriage and radially spaced apart from each other by a first predetermined distance. A radially inner one of the two magnetic heads is tilted at a first predetermined angle toward a rotary shaft with which the magnetic disc is engaged, and a radially outer one of the two magnetic heads is tilted at a second predetermined angle away from the rotary shaft, thereby bringing the magnetic gaps provided on the inner and outer peripheral heads into contact with a recording/playback surface of the magnetic disc when the disc is rotated.

Abstract: A printer paper feed apparatus having a single-form feed function and a continuous-form feed function, in which a pin tractor mechanism for feeding the continuous forms is situated upstream of the platen in terms of paper feed. The apparatus includes a guide plate member for the single forms having a base end pivotally supported in the vicinity of a single-form insertion inlet formed in an upper side of a printer main body, the guide plate member being capable of selectively assuming a horizontally accommodated position and a paper insertion guide position at which it is raised in an inclined attitude, a clutch mechanism provided in a rotating force transmission system between a tractor drive shaft of the pin tractor mechanism and the paper feed motor, and a clutch control mechanism for controlling engagement and disengagement of the clutch means in dependence upon whether the guide plate member is situated at the accommodated position or the single-form insertion guide position.

Abstract: An apparatus for rotating a magnetic disk supported by a disk hub on its central portion includes a spindle shaft rotated by a driving motor and inserted through a central hole of the disk, a rotating member fixed coaxially to the spindle shaft for corotation therewith, a drive pin arranged off-center on the rotating member and capable of being inserted through an off-center drive hole formed in the magnetic disk, a leaf spring member attached to the underside of the rotating member and including a first leaf spring portion having the drive pin implanted in one end thereof and a second leaf spring portion bent at a right angle from the other end of the first leaf spring portion, a rotational support shaft for rotatably supporting the leaf spring member, at the other end of the first leaf spring portion, on the rotating member about an axis perpendicular to the underside thereof, and a spring contact member fixed off-center to the underside of the rotating member.

Abstract: A driving unit using an electrostrictive element drives mechanical members such as, for example, a diaphragm and a shutter or a shutter blade having the function of a diaphragm blade by deformation of the electrostrictive element produced when a voltage is applied to the element, and is adapted to obtain a desired deformation quantity from the electrostrictive element regardless of the magnitude of an initial deformation quantity due to hysteresis of the element. A reference switch such as, for example, a photointerrupter operates when a predetermined reference deformation quantity is obtained in an area where the deformation quantity changes linearly in respect to variation of an applied voltage.

Abstract: A drive current of a motor is controlled by an output of a pulse oscillator having a variable duty ratio in response to a shutter release operation. Shutter blades having the function of the diaphragm blade start to open the aperture for exposure in interlocked relationship with the rotation of the motor. The shutter blades are provided with a plurality of detection marks for use in detection of the shutter blade position, and every time each of the detection marks passes through a predetermined detection point, an aperture value detection circuit produces a detection pulse. Each of the detection pulses is supplied to an operation circuit which calculates a time interval between the detection pulses. The time interval between the detection pulses is compared with a reference time stored previously in a setting device so that the duty ratio of the output signal of the pulse oscillator in the next cycle of the detection pulse is controlled to control the rotational speed of the motor.

Abstract: A dynamic pressure-type fluid bearing usable in a polygon mirror scanner for a laser beam printer includes a sleeve having an inner peripheral surface and a bottom face, and a journal having an outer peripheral surface cooperating with the inner peripheral surface of the sleeve across a predetermined clearance, and an end face cooperating with the bottom face of the sleeve. In an embodiment, the sleeve is rotatable relative to the journal and is held by a magnetic retaining force in such a manner that a predetermined gap is formed between the bottom face of the sleeve and the end face of the journal even when the bearing is at rest. The bottom face of the sleeve includes a porous body so that the gap between the bottom face and end is communicated with the outside of the bearing.

Abstract: A camera shutter using an electrostrictive strain element as a driving source wherein, in order to make it possible to make the driving voltage small and to make an accurate exposure, when the shutter is released, first a reverse voltage is applied to an electrostrictive strain element to drive a shutter blade opening and closing member in the direction of completely closing the shutter blades, then the charge accumulated in the electrostrictive strain element is discharged and finally a forward voltage is applied to the electrostrictive strain element to open the shutter blades.

Abstract: A lens shutter using an electrostrictive strain element as a driving source, arranging a shutter blades opening and closing lever and the electrostrictive strain element driving the opening and closing lever so that inertia forces acting on the opening and closing lever through engagement with the electrostrictive strain element and acting on the electrostrictive strain element through engagement with the opening and closing lever are counterbalanced by each other, in order to eliminate variations of exposure caused by various positions of a camera. The basic portion of the electrostrictive strain element is secured to a retaining member supported rotatably on a shutter base plate and the retaining member may well be biased by a spring to increase the inertia force of the electrostrictive strain element. Thereby, even if a shock is applied to the shutter from the outside, it does not occur that the shutter blades are inadvertently opened and closed.

Abstract: A magnetic disc jacket heat sealing apparatus for heat sealing thermally fusible tabs of a magnetic disc jacket. The apparatus includes a base on which the jacket is placed in folded form in order to be heat sealed, with the heat sealing being carried out while the base is heated to a temperature in the vicinity of the softening point of the jacket material. Such an arrangement eliminates distortion caused by residual thermal stress ascribable to a difference in temperature between the side of the jacket heated by a sealing mold and the side of the jacket contacting the base.

Abstract: The printer is for printing a continuous fan-folded paper web having series of perforations at each side edge thereof which is adapted to be fed into the printer from the bottom of the printer. The printer comprises an upper housing member swingably supported by a lower housing member so that the upper housing member is movable between a closed position for the printing operation and an opened position at which an accessible space is provided between the bottom of the upper housing member and the lower housing member. The upper housing member includes a printing mechanism and a pin-tractor mechanism for feeding the paper web a portion of which extends outwardly downwardly from the bottom of the upper housing member. The lower housing member has a feed-in opening at the bottom thereof for the paper web.

Abstract: In order to enable to obtain stable exposure time even for successive photographing at high speeds and completely synchronize flashing without errors, the focal plane shutter comprising a front blade group and a rear blade group is adapted in such a manner that the rear blade group is returned to its start position (folded position) substantially at the final stage of the shutter cocking travel, a retaining lever for locking the rear balde group at the unfolded position (position covering the exposure aperture) during the shutter cocking operation functions as a brake member for the rear blade operating lever, and said focal plane shutter is equipped with a movable X-contact lever which is retained at a position apart from a fixed contact by a front blade actuating arm during and after the shutter cocking operation and maintained at a position apart from the fixed contact by an X-contact release lever operated by the rear blade operating lever for the time from completion of the exposure operation to completi

Abstract: In order to make possible the automatic setting of the sensitivity of a film to be used in an exposure controlling system by a simplified structure manufacturable at a low cost, the camera auto sensing system for ISO speed comprises: a pair of switches rendered to either a conductive state or a non-conductive state by judging a digital pattern indicative of the film sensitivities provided on a film cartridge mounted in a camera; a pair of electromagnets connected to respective switches; a film sensitivity changing lever coupled to the armatures of the respective electromagnets so as to be allowed to be moved to four positions in accordance with the operative state and the non-operative state of the respective electromagnets; and light amount changing means coupled to the film sensitivity changing lever to change the amount of light incident to an exposure-controlling light-receiving device in accordance with the movement of the changing lever.

Abstract: A magnetic disk drive unit has a carriage which holds a magnetic head and travels in the radial direction of a magnetic disk, a guide shaft for guiding the carriage, a screw shaft placed in a substantially parallel relationship with the guide shaft and rotated by a motor, and a screw engagement portion of the carriage engaging with the screw shaft. One end of the screw shaft is held in a fixed position, and a bearing member supporting the other end of the screwshaft is adjustable to a certain degree. The stop position accuracy (tract position decision accuracy) of the carriage is thereby improved.

Abstract: A focal plane shutter for cameras wherein a plurality of shutter blades to open and close an exposure aperture are shared and pivoted by three arms pivoted on a base plate to secure an excellent durability even for a high speed operation. One of the three arms is pivoted on the base plate by fitting a bearing sleeve calked to the arm to a shaft standing on the base plate and the other two arms are pivoted on the base plate by fitting holes made in the respective arms to respective shafts standed on the base plate.

Abstract: A control circuit for a programming shutter includes a light receiving element which is always exposed to light from a subject to be photographed and a logarithmic compression device which logarithmically compresses a photocurrent flowing through the light receiving element in accordance with the brightness of the subject. An output voltage of the logarithmic compression device is logarithmically expanded by a logarithmic expansion device and a logarithmically expanded current from the expansion device controls currents flowing through a plurality of weighted current sources. The currents flowing through the plurality of weighted current sources are added to or subtracted from a charged current to a condenser for integrating the brightness of the subject through a plurality of current switches corresponding to the current sources.

Abstract: A magnetic disc mounting mechanism for use in a disc drive unit adapted to drive a magnetic disc while magnetically attracting and holding the disc on a spindle shaft. The coupling mechanism includes a forcible pressing member for forcibly fitting a center core of the disc onto the spindle shaft and a member which is adapted to release the pressing of the forcible pressing member while operating an ejecting mechanism. This member operates to release, after the forcible pressing member has pressed the center core of the disc onto the spindle shaft such as to couple the disc to the spindle shaft, the pressing force exerted by the pressing member so that the load of the spindle motor during driving the disc is reduced advantageously.

Abstract: A strobo control circuit includes shutter blades having the function of the diaphragm and which are opened so that an opening area thereof is substantially proportional to the square of exposure time. A distance to a subject to be photographed is detected by, for exmaple, a distance measuring circuit or a focus adjusting mechanism and a basic pulse having a period which is substantially proportional to the distance is generated. The basic pulse is supplied to a counter in interlocked relationship with the opening operation of the shutter blades so that the counter is operated. A coded film speed is inputted and when a count of the counter reaches a value determined in accordance with the coded film speed, a strobo unit is lighted so that an F number upon the flashlight illumination of the strobo unit corresponds to the film speed and the distance.

Abstract: To eliminate manual cocking operation and to facilitate in making the size of a camera compact, a spring made of a shape memory alloy plastically deformable at normal temperature but restoring a powerful resiliency when heated is associated with the shutter driving mechanism in arranging the shutter driving mechanism so that the latter assumes its cocked state in its normal state and that, upon depression of the shutter button, an electric current is supplied to the above-mentioned spring to heat same and to cause an opening and closing movement of the shutter blades by virtue of the resulting resiliency gained by the spring, and that upon completion of the opening and closing movement of the shutter blades, the conduction of electric current to the spring is cut off to deprive this spring of its resiliency whereby automatically causing the shutter driving mechanism to resume its cocked state.

Abstract: Device for holding a helically wound wire resistor of a potentiometer in a helical groove comprising, an outer cylindrical member having an inwardly projecting ridge extending over the length thereof and a projecting claw, and an inner cylindrical member of an elastic nature having an outer surface engagable with the inner surface of the outer member, wherein the inner member has a cut out portion extending over the length thereof to receive the ridge from the outer member, and a recess in the outer surface to receive the claw of the outer member.

Abstract: A magnetoresistance element is arranged in a plane parallel to the end face of a PG yoke and is situated on the outer side of a circle described by revolution of the PG yoke end face and in close proximity to the end face to detect a characteristic flux component emitted from the PG yoke end face. The magnetoresistance element is disposed in such a manner that an acute angle is formed between the direction of a current flowing in the element and a normal line extending from the axis of rotation of a recording medium. A flux component hardly influenced by the area of the PG yoke end face is thus detected.