Abstract: A rubber injection molding device comprising: a mold having a molding cavity therein; an injecting machine including an injection cylinder having an injection chamber for storing a rubber therein, and an injection plunger for injecting the rubber from the injection chamber into the molding cavity by means of an advancement of the injection plunger; a feed machine having a feed cylinder with a feed aperture formed at a tip end thereof and connected with the injection chamber through a feed duct, and being adapted to feed into the injection chamber, through the feed duct the rubber in a mixed state, and a pushing assembly which pushes into the injection chamber the rubber that remains within the feed duct after a feed operation of the rubber by the feed machine. A manufacturing method of a rubber product by using the molding device is also disclosed.

Abstract: A rubber injection molding device comprising: a mold hang a molding cavity therein; an injecting machine including an injection cylinder having an injection chamber for storing a rubber therein, and an injection plunger for injecting the rubber from the injection chamber into the molding cavity by means of an advancement of the injection plunger; a feed machine having a feed cylinder with a feed aperture formed at a tip end thereof and connected with the injection chamber through a feed duct, and being adapted to feed into the injection chamber, through the feed duct the rubber in a mixed state, and a pushing assembly which pushes into the injection chamber the rubber that remains within the feed duct after a feed operation of the rubber by the feed machine. A manufacturing method of a rubber product by using the molding device is also disclosed.

Abstract: A vibration-damping device for damping vibrations of a vibrative member, which includes a damper mass member having a rigid abutting portion, a spring member for elastically connecting the damper mass member to the vibrative member to cooperate with the damper mass member to constitute a second vibration system whose natural frequency is tuned to a frequency band of the vibrations of the vibrative member, and an independent mass member disposed so as to be opposed to the rigid abutting portion in a vibration input direction with a given gap therebetween without being adhesive to the rigid abutting portion. The independent mass member is independently displaceable relative to and brought into abutting contact directly and elastically with said rigid abutting portion in said vibration input direction.

Abstract: Disclosed is a dynamic damper for use in a steering system of an automotive vehicle, including a mounting member connectable to a steering column or a steering wheel of the steering system; and a plurality of secondary vibration systems independent of each other, each including a mass member and a spring member for elastically supporting the mass member to the mounting member. One of the plurality of secondary vibration systems has a natural frequency that is tuned to an idling vibration frequency band ranging from about 20 Hz to about 30 Hz, and another one of the plurality of secondary vibration systems has a natural frequency that is tuned to a natural frequency band of the steering system, which is larger than 30 Hz.

Abstract: Disclosed is a dynamic damping device for a steering system of an automotive vehicle, which equipped with a telescopic steering column, including a plurality of mutually independent dynamic dampers, each including a mass member and a spring member for elastically supporting the mass member to the steering column or wheel. At least two of natural frequencies of the plurality of dynamic dampers are tuned to a higher and a lower frequency range in relation to a central value of a range of variation in a natural frequency of the steering wheel due to an expansion or contraction of the telescopic steering column, within the range of vibration in the natural frequency of the steering wheel. Further, a difference between adjacent ones of the natural frequencies of the plurality of dynamic dampers is made held within 10-40% of the central value of the range of vibration in the natural frequency of the steering wheel.

Abstract: A vehicle shock absorber includes a housing, and a shock-absorbing member. The housing has at least one hollow formed therein, is formed of a rigid material, and is fixed to a bone structural member of vehicles. The shock-energy absorbing member is disposed in the hollow of the housing at least, and is formed of a super plastic polymer material. The super plastic polymer material exhibits a tensile breaking elongation of 200% or more, a yield strength of 20 MPa or more with respect to a predetermined strain, and a tensile elastic modulus of 400 MPa or more.

Abstract: Disclosed is a dynamic damping device for a steering system of an automotive vehicle, which equipped with a telescopic steering column, including a plurality of mutually independent dynamic dampers, each including a mass member and a spring member for elastically supporting the mass member to the steering column or wheel. At least two of natural frequencies of the plurality of dynamic dampers are tuned to a higher and a lower frequency range in relation to a central value of a range of variation in a natural frequency of the steering wheel due to an expansion or contraction of the telescopic steering column, within the range of vibration in the natural frequency of the steering wheel. Further, a difference between adjacent ones of the natural frequencies of the plurality of dynamic dampers is made held within 10-40% of the central value of the range of vibration in the natural frequency of the steering wheel.

Abstract: Disclosed is a dynamic damper for use in a steering system of an automotive vehicle, including a mounting member connectable to a steering column or a steering wheel of the steering system; and a plurality of secondary vibration systems independent of each other, each including a mass member and a spring member for elastically supporting the mass member to the mounting member. One of the plurality of secondary vibration systems has a natural frequency that is tuned to an idling vibration frequency band ranging from about 20 Hz to about 30 Hz, and another one of the plurality of secondary vibration systems has a natural frequency that is tuned to a natural frequency band of the steering system, which is larger than 30 Hz.

Abstract: A vibration-damping device for damping vibrations of a vibrative member, which includes a damper mass member having a rigid abutting portion, a spring member for elastically connecting the damper mass member to the vibrative member to cooperate with the damper mass member to constitute a second vibration system whose natural frequency is tuned to a frequency band of the vibrations of the vibrative member, and an independent mass member disposed so as to be opposed to the rigid abutting portion in a vibration input direction with a given gap therebetween without being adhesive to the rigid abutting portion. The independent mass member is independently displaceable relative to and brought into abutting contact directly and elastically with said rigid abutting portion in said vibration input direction.

Abstract: A double-mass type dynamic damper mounted on a rod-shaped oscillating member, which includes a first damper system and a second damper system that are tuned to two different frequency ranges. Each of the damper systems includes a cylindrical mass member disposed radially outwardly of the oscillating member, and an elastic support member for elastically supporting the mass member with respect to the oscillating member. The elastic support members of the two damper systems are disposed in series and connected to each other in the axial direction. The dynamic damper further includes an elastic connector formed by adjacent parts of the two elastic support members, for elastically connecting axially opposed faces of the two mass members.

Abstract: A rod-damper combination comprising an oscillating rod member and a dynamic damper mounted on the rod member is disclosed. The dynamic damper includes a mass portion having a substantially cylindrical shape, and two elastic support members formed on axially opposite sides of the mass portion to elastically support the mass portion. The oscillating rod member includes a small-diameter portion formed at an axially middle portion thereof, and two large-diameter portions formed on axially opposite sides of the small-diameter portion. Alternatively, the rod member includes a middle portion, and two tapered portions on axially opposite sides of the middle portion. The two elastic support members of the dynamic damper are mounted on the two large-diameter or tapered portions of the oscillating rod member, respectively.

Abstract: A rod-damper combination comprising an oscillating rod member and a dynamic damper mounted on the rod member is disclosed. The dynamic damper includes a mass portion having a substantially cylindrical shape, and two elastic support members formed on axially opposite sides of the mass portion to elastically support the mass portion. The oscillating rod member includes a small-diameter portion formed at an axially middle portion thereof, and two large-diameter portions formed on axially opposite sides of the small-diameter portion. Alternatively, the rod member includes a middle portion, and two tapered portions on axially opposite sides of the middle portion. The two elastic support members of the dynamic damper are mounted on the two large-diameter or tapered portions of the oscillating rod member, respectively.