Harada Kogyo Kabushiki Kaisha

Harada Industry Co., Ltd.

Misao Kimura

Shinichi Saito

Masaki Shinkawa

Jiro Harada

Kiyoshi Tetsuka

Koji Arata

Misao Shinkawa

A telescopic rod antenna apparatus of the present invention includes a mechanism for extending/retracting a telescopic antenna element by operating a smallest-diameter one of rods of the antenna element, and a means for setting the rods in the second state where a tip portion of a largest-diameter rod contacts an O-shaped ring seal means and then extending the antenna element using the mechanism, setting the rods in the second state where the antenna element is retracted using the mechanism, and displacing the second state to the first state where the largest-diameter rod is returned to the initial position of a holding tube to bring a top portion into contact with the O-shaped ring seal means.

Telescopic rod antenna apparatus

A telescopic rod antenna according to the present invention includes an antenna element and a waterproof ring-shaped seal member which is inserted in a ring-shaped gap in a joint between two rods of the antenna element. The ring-shaped seal member is obtained by shaping a thermoplastic resin film strip, on which at least one projecting portion is formed in its longitudinal direction, like a ring and compressing and inserting a ring-shaped film into the ring-shaped gap. A plurality of ring-shaped contact portions are formed on both sides of the film strip in its longitudinal direction while the projecting portion of the film strip serves as a basic contact portion. The ring-shaped contact portions are adhered to the inner surface of the larger-diameter rod and the outer surface of the smaller-diameter rod at a predetermined pressure. The tip portion of the smallest-diameter rod is provided with a short cylinder member fitted to the outer periphery of the tip portion of the smallest-diameter rod, and a stopper member for sealing an open end of a hollow of the short cylinder member.

Telescopic rod antenna and method for manufacturing the same

Automobile antenna

A multi-stage telescopic antenna for use in vehicles and a method for manufacturing such an antenna in which the antenna element, which comprises uppermost rod and conductive pipes, is free of any bending or breaking damage even if a large load is applied to the antenna element from a lateral direction, and there is no permanent deformation occurs even after the load is removed, so that the antenna element can always be maintained straight and smooth and stable extension and retraction can be executed. At least the conductive pipes 12 through 14 are formed from a high-elasticity material obtained by heat-treating SUS 631. In the heat treatment, the material is heated at a standard temperature of 480.degree. C..+-.5.degree. C. and then gradually cooled.

Method for manufacturing a telescopic antenna for vehicles

An electric extensible car antenna including an antenna element support cylinder detachably mounted to a cylindrical support member of an antenna attachment base from the outside of a car body; a single small-diameter rod antenna element inserted in an antenna element insertion hole of the support cylinder so as to be in contact with a conductive contact element; the proximal part of the antenna element led toward the proximal end of the support cylinder being guided in a direction by an antenna element guiding tube; and an antenna element extended and retracted by a rack-equipped flexible rope connected to the antenna element via an electric mechanism. It is desirable that the antenna element be made of an ultra-flexible material and that the support cylinder is made of a plurality of separate cylindrical units. Thus, the antenna has a very small risk of becoming damaged, has a simple construction, allows easy manufacturing, allows stable attachment of the antenna element, is highly compatible in terms of components, allows storage of the long antenna element in a small space inside the car body without failure and allows the antenna element to be automatically extended and retracted by the electric mechanism.

Electric extensible car antenna

A drive control apparatus for an electrically-driven type extensible/retractable antenna comprises a control circuit connected to a power supply, a motor controllable by the control circuit to be rotated in a normal or a reverse direction, a multi-threaded type worm provided on an output shaft of the motor, a worm wheel engaging with the worm, a drive gear receiving a rotational force of the worm wheel to allow it to be rotatably driven, a drive rope having a rack in mesh with the drive gear and adapted to be moved in a longitudinal direction upon the rotation of the drive gear, an extensible/retractable antenna element driven by the drive rope to allow it to be extended or retracted, stopper means for mechanically stopping an extending or a retracting motion of the antenna element when the antenna element reaches an extension or a retraction limit, a shock absorber made up principally of an elastic member for alleviating an impact force by which the antenna element is stopped upon collision with the stopper means, the elastic member being placed partway on a movable system from the output shaft of the motor to impact portions colliding with the stopper means, and switching means provided in the control circuit and adapted to cut off the power supply to the motor when an elastic deformation of the shock absorber is stopped.

Drive control apparatus for an electrically-driven type

A clutch for telescopic antenna including a disk shape clutch element and a shallow, cylindrical clutch element facing each other. The cylindrical clutch element is provide with a recess on its inner wall, and the disk shape clutch element is provided with a pair of sliding contacts which are urged in the radial directions and can come into contact with the inner wall surface of the cylindrical clutch element. An engagement ball provided in one of the sliding contacts can engage with the recess of the second element, securing the coupling of the two clutch elements.

Clutch device for electrically extensible antennas

A rod antenna including a plurality of rods of respectively different diameters which are coupled with each other in a manner to be slidable. Each of the larger diameter rods is provided with a rectangular strip of film made of resin such that it is mounted in a ring shape at least at the inside joint area for coupling the larger diameter rod with the smaller diameter rod. The rod antenna can be low in cost since the cutting process done for the conventional antennas is eliminated, and the rectangular film strip is inexpensive and can be easily mounted. Besides, a satisfactory waterproofing can be obtained as the rectangular strip of film is excellent in heat resistance, cold resistance, water repellency, wear resistance, etc. Furthermore, the operating noise of rods during the extension or retraction of the antenna is low and the appearance of the rod can be kept clean.

Rod antenna

A clutch system for a motor driven telescopic antenna, a first rotor provided on a main shaft for moving an antenna drive cord of a telescopically adjustable antenna, a second rotor fitted over the main shaft and rotated by an electric motor, first and second clutch discs which are inserted over the main shaft and kept pressed in the shaft direction by a clamp in order to press hold both end surfaces of the second rotor in between by applying a pressurizing force to the second rotor. The clutch system further includes a clutch pressure setter for dissociating the first and second clutch discs from the second rotor when the force exceeding a specified clutch pressure that is set in relation to the engagement with the main shaft acts on the holding surfaces between the second rotor and the first and second clutch discs. The clutch pressure setter includes first uneven portions formed on both end surfaces, in the shaft direction, of a ring-form member that is coaxially inserted over the main shaft and on the center side of the second rotor and second uneven portions formed in the first and second clutch discs corresponding to the first uneven portions of the ring-form member.

Clutch system for motor driven telescopic antenna

An automobile antenna including a cylindrical housing for storing an antenna element, an antenna extension wire for extending and retracting the antenna element, cables connected to the antenna element at one end and the other end to communication equipment, and a cable chamber for storing therein a part of the cables. The cable chamber includes a wind-up shaft with a spiral fin formed around the outer circumference thereof, and the cables are wound along the spiral fin such that the coil diameter of the cables around the wind-up shaft is reduced and increased along the spiral fin upon the extension and retraction operations of the antenna element.

A driving rotary member which is rotatably fitted around a main shaft is rotated by a driving force from a motor. An intermediate gear is rotatably provided on one surface of the driving rotary member so as to have a different axis from that of the main shaft. A clutch gear having a gear portion, meshing with the intermediate gear and a clutch disk member, is rotatably fitted around the main shaft. A clutch plate is fitted around the main shaft so as to be rotated integrally with the driving rotary member while being brought into contact with the clutch disk of the clutch gear. The clutch plate is brought into contact with the disk of the clutch gear by a contact means. A driven rotary member having a gear portion on an inner surface thereof which meshes with the intermediate gear is also fitted around the main shaft so as to be rotatable together with and relative to the driving rotary member. A driving force transmitted from the driving rotary member is supplied to the antenna by the driven rotary member.

Growing community of inventors

Yokosuka, Japan

Misao Kimura