Abstract: A self-contained type automatic belt tensioner adjusts a tension of an engine timing belt for automobiles. The tensioner comprises a body, a plunger slidably mounted in the body, a reservoir chamber located in the plunger, a pressure chamber disposed between the plunger and a closed wall of the body, a rod member fixed to the plunger, a bellows shaped elastic diaphragm located in the reservoir chamber with one end thereof being fixed to the rod member and the other end being fixed to the body, a check valve allowing a fluid flow only from the reservoir chamber to the pressure chamber, and a return spring interposed between the plunger and the closed wall of the body so as to bias said plunger in the direction of the rod member.

Abstract: A crank damper pulley structure of an internal combustion engine of a car in which the hub of a pulley, which is removably fixed to the tip of the engine crank shaft and transmits power to auxiliary machinery, such as an alternator, has therearound a damper mass and a damper rubber comprising a torsional damper. The hub has a cavity therein which opens to one end of the hub. A damper support is fixed in the cavity and a ring-like damper and a ring-like damper mass are superposed axially with the rubber being fixed to the mass and the support in order to constitute a ring-like dynamic damper disposed in the cavity which copes with bending vibration of the crank shaft.

Abstract: A cushioned mounting device for use in mounting an engine to the body of a vehicle such as an automobile, having first and second frame members arranged to oppose to each other, a mass member having a plate portion and disposed between the first and the second frame members, a first cushion member disposed between and flexibly connecting together the first frame member and the mass member, and a second cushion member disposed between and flexibly connecting together the second frame member and the mass member, wherein the mass member, together with the first and the second cushion members, forms a sub-oscillation system which can provide less than one transmission ratio relative to an oscillation system supposed to be composed of the engine supported by this cushioned mounting device and the first and the second cushion members which can also provide less than one transmission ratio, whereby the cushioned mounted device cna provide a low overall transmission ratio which is substantially the multiplication of

Abstract: A rubber bearing device having air damping capacity which comprises upper and lower fitments;a rubber cylindrical body interposed between the fitments defining an air chamber capable of volume-changing;a rubber piston shaped body whose shaft is fitted hermetically in the cylindrical body and is firmly bonded to the upper fitment, said piston-shaped body being provided in the air chamber to divide it into upper and lower air chambers, said upper and lower air chambers being adapted to release air therefrom or to admit air thereto through an orifice; anda depression diaphragm member provided associating with one or both of the chambers, said diaphragm member being capable of decreasing the magnitude of effective volume change by a definite magnitude.

Abstract: A muffler for automobiles having a drum-shaped expansion chamber of diameter D and length h, to which gas inlet and outlet pipes and an insert pipe of a Helmholtz resonator open so that the gas flow traverses the expansion chamber substantially diametrically therethrough, wherein the ratio h/D is substantially 0.25 - 0.4.