Abstract: A thermally self-regulating elastomeric composition and heating element made therefrom. The composition includes a body of elastomeric material in which is distributed electrically conductive particulate material, such as carbon black. Short fibers are also distributed in the elastomeric matrix. In the disclosed invention, the short fibers are present in the amount of approximately 0.5 to 20 volume percent. In one alternate form, the matrix is foamed. Different arrangements of the electrodes in electrical conductive association with the thermally self-regulating elastomeric body are disclosed. Preferred proportions and characteristics of the particulate conductive material and short fibers providing optimum thermally self-regulating characteristics of the composition are disclosed.

Abstract: A power transmission belt having a flexible chain link midportion 11 defining a longitudinally continuous belt structure having opposite laterally outer side portions. Mounting elements 14,15 protrude from the side portion at spaced intervals longitudinally of the belt and side elements 16 are freely adjustably mounted one each to the protruding mounting element portions 15. The side elements define an outer surface for engaging the sidewall of a drive pulley V-groove. The invention further comprehends the provision of positioning elements 26 for retaining the side elements on the mounting elements, with the outer surfaces 17 of the side elements generally parallel to the V-groove sidewalls of the pulley for facilitating facial engagement of the side elements with the sidewall of the pulley groove when brought thereinto.

Abstract: The present invention is directed to an apparatus for automatically delivering power transmission belt preforms from a supply to a work station for entrainment on a pair of cooperating pulleys, in which position a cutting, abrading operation, or the like can be performed on the belt. Once the belt is completed, structure automatically removes the belt from the pulleys and delivers the same to a desired destination.

Abstract: A variable speed pulley having rearrangement structure for causing uniform distribution of a plurality of force applying elements utilized to control the width of the pulley groove as a function of the centrifugal forces developed during changes in the speed of the pulley. The rearrangement structure includes a coil spring connected in the structure to permit relative rotational movement between the fixed and movable pulley sheave halves as a result of changes of the force applied to the movable pulley sheave half during driving operation of the pulley. The rearrangement structure effectively minimizes vibration and noise by providing improved uniformity in the distribution of the force applying elements both in the steady state and speed and force changing conditions of the pulley.

Abstract: A method of joining narrow waterproof sheets to obtain a waterproof sheet of wide width having a gently curved joint which is free from any acutely stepped portion. It comprises disposing a cure tape between the overlapping edge portions of the sheets to be joined, positioning a piece of cushiony material below or above the overlapping edge portions, and heating the overlapping edge portions and the cure tape under pressure. The cure tape has a width which is substantially equal to that of the overlapping edge portions before pressure is applied thereto. When pressure is applied, the cure tape projects in opposite directions beyond the extremities of the overlapping edge portions. One form of the joint thus formed is flat on one surface and gently curved on the other surface, while another form is gently curved on both surfaces thereof.

Abstract: An endless power transmission belt comprising a plurality of V-belt parts spaced laterally apart from one another and tie band having an improved structure and connecting the V-belt parts together. The V-belt part and the tie band are essentially made of elastomer material and fabrics. More specifically, the tie band is made up of at least two cord fabric layers and an elastomer material in which the cord fabric layers are embedded. An intermediate elastomer material layer is provided between the fabric layers. The fabric layers are made of cords which are extended obliquely with respect to the longitudinal axis of the belt in such a manner that the cords forming one fabric layer form an angle with the cords forming another fabric layer adjacent thereto. The upper surfaces of the plurality of V-belt parts are connected by the tie band thus constructed, to form one unit.

Abstract: An apparatus for testing power transmission belts is disclosed, wherein a drive belt is mounted between at least one drive motor and at least one intermediate shaft, and a test belt is mounted between at least one driven motor and said intermediate shaft. A variable load is applied to the test belt by causing an r.p.m. differential between the motors and a slippage of the belts with respect to pulleys secured to the drive and driven motors and the intermediate shaft.

Abstract: An apparatus for testing power transmission belts is disclosed, wherein at least one test belt is mounted between at least one drive and driven motors each having corresponding numbers of drive and driven pulleys, respectively. The pitch diameter of the drive pulley is larger than that of the driven pulley to generate electric power in the driven motor. The test belt is subject to various loads due to torque variation of both drive and driven motors or either one of the motors by connecting a transformer to both or either one of the motors.

Abstract: A rubber screen for a vibratory screening apparatus comprises a plurality of first parallel rope members having suitable cross sectional shapes and arranged in a particle flowing direction, each of said first rope members having a tensile member composed of a strand of filament having a high elongation at break and an organic material having flexibility and/or elasticity and covering the tensile member, and a plurality of second parallel rope members having suitable cross sectional shapes and arranged in a direction normal to the first rope members, each of the second rope members having a tensile member of a material having a low elongation at break and an organic material having flexibility and/or elasticity and covering the tensile member, each point of intersection between the first and second rope members being suitably bonded.