Murata Manufacturing Co., Ltd.

Kazunori Yoshimura

Katsuo Ito

Bunjiro Murata

Kazuo Kontani

Yoji Maeda

Eiichi Hibino

Kazuhiro Tsuji

Kenichi Yamaguchi

An improved fine adjusting mechanism for a preset type tuner, which is so arranged that, with a ring having cam portions being fitted under pressure onto a fine adjusting shaft of a tuner for simultaneous rotation with it and also for slippage with respect to the fine adjusting shaft against a torque larger than a predetermined extent, a lever having a transmission gear rotatably mounted on it is urged by a spring force so that its actuating projections are held in pressure contact with the cam surface of the ring with the cam portions, so that rotation of the fine adjusting shaft is converted into a pivotal movement of the lever through the ring so as to positively engage the transmission gear with each of gears having threaded portions for an efficient local oscillation frequency adjustment.

Fine adjusting mechanism for preset type tuner

A CATV system comprises two coaxial cables (11, 12) for transmitting information obtained from a center unit, a slide switch (1), and a CATV converter (30). As a slider (73) of the slide switch is slided in one direction with the same in contact with a common contact (101) connected to the CATV converter, the slider is placed in contact with a first fixed contact (104) connected to one coaxial cable while a first terminating contact (110) connected to a first terminating resistor (13) is separated from the first fixed contact. When the slider is slided in the other direction, the slider is placed in contact with a second fixed contact (107) connected to the other coaxial cable, while a second terminating contact (111) connected to the second terminating resistor (14) is separated from the second fixed contact. Accordingly, each of the coaxial cables is not opened through selection of the slide switch, whereby mixing of an image is prevented from occurring due to mismatching.

CATV System

A housing for an electronic tuner or the like comprises: a shield frame defining a space to house circuitry, and an auxiliary base plate enclosing one side of the space left open by the frame and preferably serving to shield the circuitry in cooperation with the shield frame. A novel structure is disclosed for mechanically securing the auxiliary base plate to the shield frame simply and in such a manner that the auxiliary base plate can be easily removed if necessary. The frame and the auxiliary base plate engage each other elastically and resiliently by means of tongues, apertures and/or notches. No special step of either soldering or bending the auxiliary base plate or shield frame with pliers, etc., is required to maintain the parts in position. One or more shield plates may be supported by the auxiliary base plate and the shield frame and divide the space into sections.

Provisional fixing structure of electronic tuner

A fixing structure is disclosed for fixing an intermediate frequency transformer or other electronic component to a flexible and deformable base plate. The component comprises a base portion for fixing it to the base plate and the base plate is formed with an aperture for receiving the base portion. The base plate includes a strip portion extending along a portion of the periphery of the aperture. The component is provided with a protrusion which extends laterally from the base portion thereof. The protrusion is so formed and so located on the base portion of the component that when the base portion is inserted into the aperture, the protrusion engages the strip portion and deforms it in a direction perpendicular to the surface of the base plate, so that the diameter of the aperture shrinks, whereby the base portion is strongly gripped by at least a portion of the periphery of the aperture.

Fixing structure of electronic component

A rotary type television tuner includes a chassis and a channel changing shaft extending through the chassis and having an operating knob mounted on the front end thereof for rotating the shaft. The channel changing shaft is made of a synthetic resin reinforced with glass fiber and is circular in cross-section over the greater part, the knob mounting section being formed with a flat portion and having a cross-section that is nearly semicircular. The root of the flat portion of the knob mounting section is rounded. A reinforcing rod assembly comprising a reinforcing rod made of a metal and a reinforcing rod made of a rigid synthetic resin which are connected together as by threads is embedded in the channel changing shaft including its knob mounting section. The length of the reinforcing rod of metal is such that when it is assembled as the tuner, it extends from the front end nearly to the chassis plate.

Toning shaft for a rotary switch

A coaxial cable connector receptacle comprises a cylindrical shield casing made of a metallic plate and having openings at both ends, and an inner casing made of an insulating material and housed inside the shield casing and having apertures at both ends corresponding to the openings of the shield casing. The inner casing is formed of a protruding portion at the side surface thereof, the protruding portion being formed of a groove communicating with the inside of the inner casing and receiving a contact of an external circuit. A contact member having a first and second contact is provided inside the inner casing and the first contact is positioned for receiving a center conductor of a coaxial cable at the position opposing one aperture of the inner casing, while the second contact is formed at the position opposing the groove of the protruding portion in the direction orthogonal to the longitudinal direction for receiving a contact of the external circuit. The center conductor of the coaxial cable is placed in contact with the first contact of the contact member through the opening of the shield casing and the aperture of the inner casing, while the contact from the external circuit is placed in contact with the second contact of the contact member through the groove of the protruding portion.

Coaxial cable connector receptacle

A coaxial cable is electrically connected to a connector receptacle by means of a coaxial cable connector plug. The coaxial cable connector plug comprises a clip which acts as an elastic pressure contact connected to a central conductor of the coaxial cable, and a plug pin electrically connected to the clip and adapted to be inserted into a receptacle opening of the connector receptacle. The clip and the plug pin are integrally formed in a single metallic plate. The clip is formed by folding the metallic plate at one end portion, while the plug pin is formed at the other end portion of the metallic plate by curling the same, with engaging portions being formed at the joint portion of the clip and the plug pin and protruding in the direction orthogonal to the longitudinal direction. The clip is housed in an insulating inner casing, while the pin is guided outward extending therefrom. The inner casing is covered with a shield casing. The inner casing is formed with an aperture for insertion of a center conductor of a coaxial cable at the position corresponding to the clip and the shield casing is formed with an aperture for insertion of an inner insulation of the coaxial cable at the corresponding portion. An outer conductor of the coaxial cable is pressure fixed to the side surface of the shield casing.

Coaxial cable connector plug

The present invention relates to a rotary switch which is an improved stator provided with a plurality of projections extending outwardly from its edges to confront the corresponding surfaces of an improved chassis or the like to which the stator is to be secured. The improved chassis is formed, in positions corresponding to the positions of the projections of the stator, with openings or cutout portions each having a claw which can be deformed or bent. By bending the claws toward the projections after inserting the projections into the openings in the chassis, the projections of the stator are firmly held between the chassis and the claws and rigidly secure the stator to the chassis.

Rotary switch

A VHF television tuner for selection of a broadcasting television signal through mechanical switching selection of inductance coils, comprising; a tuner casing; a mechanical channel selection switch arrangement provided in said casing and including a rotatably mounted channel selection shaft for selection of inductance coils by rotation of said shaft; a radio frequency amplifier operatively coupled to the selected inductance coils for selectively amplifying a desired radio frequency signal; a local oscillator operatively coupled to said selected inductance coils for providing a local oscillation frequency signal, the frequency of which is different by a given frequency difference from said selectively amplified radio frequency signal; a mixer responsive to the radio frequency signal from said radio frequency amplifier and the local oscillation frequency signal from said local oscillator for providing an intermediate frequency signal; and an intermediate frequency tuned circuit for selectively withdrawing said intermediate frequency signal, said intermediate frequency tuned circuit comprising an intermediate frequency transformer, said intermediate frequency transformer comprising an intermediate frequency coil wound around a bobbin having a given axis and a magnetic core threadably inserted in said bobbin for adjustment of the inductance value of said intermediate frequency coil by rotation of said magnetic core about said axis of said bobbin, said intermediate frequency transformer being provided in said casing such that the axis of said bobbin is oriented in the direction substantially parallel to the axial direction of said channel selection shaft, said casing being formed of an aperture at the position in alignment with the axis of said bobbin, whereby access to said intermediate frequency transformer is allowed from the outside of said casing for adjustment of the inductance value of said intermediate frequency transformer.

VHF Television tuner with easy/flexible access

A tuner for use in a telecommunication receiver having a rotary drum carrying a plurality of oscillation coils and a fine tuning member for each coil supported for movement inside of the coil for fine tuning and having a geared head, and a main shaft on which the rotary drum is rigidly mounted, and a fine tuning mechanism which has a hollow shaft coaxially mounted on the main shaft for movement between projected and retracted positions and having a drive gear mounted thereon and a transmission gear assembly for transmitting the rotational force of the hollow shaft to the geared head of any one of the fine tuning members. The transmission gear assembly is supported by a support plate assembly.

Fine tuning mechanism in a tuner

A television tuner including a fine tuning mechanism, said mechanism comprising a cam body provided to a sleeve rotatably disposed around the operating shaft, said cam body having a cam surface adapted to convert rotary motion to reciprocating motion, and fine tuning means including a bobbin having a coil around the outside thereof, and a plunger having at one end a core adapted to be disposed within said bobbin, said plunger being L-shaped and composed of a plunger body provided with a core at one end and an arm portion at the other end, said arm portion being kept in contact with said cam surface at the free end thereof so that the plunger reciprocates said core within said bobbin with the rotation of said sleeve.

Growing community of inventors

Kanazawa, Japan

Kazunori Yoshimura