Abstract: A desk-top electronic calculator and cassette tape recorder assembly is provided which includes a housing in the form of a triangular prism. Input keys and a numeral display are disposed on one side of the housing while a cassette receiving chamber for the tape recorder is formed in another side thereof so that each side may be placed on the front side to permit an optimum manipulation of the calculator and the recorder, respectively. The assembly is compact in construction for convenience in portable use. The remaining side of the housing may be utilized in conjunction with another instrument.

Abstract: A magnification display device for displaying magnification on a part in the observation field of view or photographing field of view of a zoom type microscope. The device comprises a mirror frame for the microscope incorporating with a zoom lens, and a magnification display plate rotatably arranged in the mirror frame. A predetermined magnification on the magnification display plate is displayed in the field of view of observation optical system, photographing optical system or the like.

Abstract: A small current switch comprises a pair of juxtaposed, resilient conductive wires each carrying a coiled reinforcement formed intermediate its ends. One end of each wire is secured to an insulating base. One of the wires has its other end extending in a straight form while the other end of the other wire is bent substantially at right angles so as to extend in a direction perpendicular to the one wire, the free end of which is mounted on a switching member. The switching member may be moved to bring the connected wire into and out of electrical contact with the other wire.

Abstract: A focal plane shutter comprises a first and a second blind, a take-up and a winding drum supporting the opposite ends of the first blind, a take-up and a winding drum supporting the opposite ends of the second blind, a first blind winding pinion and a second blind winding pinion having an operationally integral relationship with the first and the second blind winding drum, respectively, and a pair of shutter winding sector-shaped gears in meshing engagement with the first and the second blind winding pinion, respectively, and adapted to rotate in response to a shutter charging command. Each of the sector-shaped gears have a hiatus which is located opposite to the associated pinion to release the meshing engagement when no shutter winding operation takes place. The sector-shaped gears and the pinions are located relative to each other in a manner such that rotation of the first blind winding pinion precedes rotation of the second blind winding pinion when a shutter winding operation is to be commenced.

Abstract: A dynamoelectric machine comprises a flat coreless rotor rotatably mounted in a housing which also serves as a yoke, a commutator integrally mounted on the rotor, a magnet disposed in juxtaposition with and in opposing relationship with one of the major surfaces of the rotor, and a brush assembly disposed for sliding contact with the commutator. The commutator is electrically connected with the rotor winding on the side of the rotor which is adjacent to the one major surface thereof, and extends to the opposite side of the rotor for sliding engagement with the brush assembly, whereby the dynamoelectric machine is miniaturized.

Abstract: A daytime strobo apparatus is provided for a camera which includes an electric shutter, and a control circuit which controls the operation of the electric shutter in accordance with the amount of light incident on a photoelectric transducer element and which is operatively associated with or internally houses a strobo unit. The strobo apparatus comprises a strobo decision circuit in the control circuit which is responsive to the photoelectric transducer element, a decision level adjusting circuit for adjusting an input level from the transducer element to the decision circuit, an X-contact drive circuit responsive to the decision circuit, and the above strobo unit. The apparatus is operative to energize the strobo unit at a timing subsequent to the initiation of operation of the electric shutter which is determined by the operation of the various circuits.

Abstract: An apparatus for automatic application of blood serum to a serum bearing film for use in a cataphoretic process includes a serum supply station, a serum application station, a rinsing station and a drip station. The apparatus also comprises a guide along which a serum applicator is sequentially moved through each of these stations, as well as operation controlling microswitches and a cam assembly.

Abstract: A photometric apparatus for single lens reflex camera and of the type in which an exposure value is determined by photometry of light which is transmitted through a photographic optical system and is reflected by at least one of the surfaces of a shutter blind and a film, said apparatus comprising a photoelectric transducer element for receiving light reflected by at least one of the surfaces of a shutter blind and a film, and an operational amplifier for biasing the photoelectric transducer element to maintain the voltage applied thereacross substantially null, thereby enabling a photometric output of the photoelectric transducer element to be effectively derived even when the amount of light received is minimal. The shutter blind is provided with a surface upon which at least two portions thereof have different coefficients of reflectivity to reduce adverse effects of reflected light upon the desired exposure period.

Abstract: A circuit for eliminating a.c. noise current which is produced as a result of the interruption of electrical contact between a brush and a commutator of a d.c. motor and comprises a capacitor which applies the noise current to a transistor, which in turn inverts the waveform of the current and applies it in an inverted phase to a power source for the motor, thereby cancelling the a.c. noise.

Abstract: An apparatus for adjusting the light source position of a light source assembly comprises a lamp socket for mounting a lamp at an eccentric position thereon, and a sleeve secured to a lamp housing for mounting the lamp socket so as to be slidable along the axis and rotatable about the axis of the sleeve. By axially sliding the lamp socket relative to the sleeve or by rotating the lamp socket about the axis, the position of the lamp can be optimally adjusted relative to a condenser which is mounted on the lamp housing.

Abstract: A microphone holder essentially comprises a microphone supporting cylinder for mounting a microphone therein, an attaching cylinder located outside the supporting cylinder, and a stepped connecting cylinder for connecting the supporting and attaching cylinders together, all of which are integrally formed of a resilient material to support the microphone in suspension, thereby isolating it against oscillations which may be imparted thereto.