Abstract: An overhang type electromagnetic clutch used for selectively connecting the rotation of an internal combustion engine to a compressor for an air conditioning system for an automobile. The clutch is provided with a rotor having a sliding surface axially spaced from an outer end of a pulley arranged around the rotor. A bit, which initially is in contact with the sliding surface at a location spaced from the axis of the rotation of the rotor, is radially moved while the rotor is rotated, so that radially spaced apart tool marks eccentric to the axis of the rotation of rotor and having a gradually increased radius are formed on the entire region of the sliding surface. An increased engagement of the sliding surface with an armature is obtained due to the provision of engagements in the circumferential direction.

Abstract: Carbon fiber superior in processability and in physical properties as a composite is obtained by treating carbon fiber with an epoxy resin composition incorporating a polyalkylene ether glycol derivative represented by the following general formula (I) or (II): ##STR1## wherein R.sub.1 is alkylene of C.sub.1 to C.sub.30, R.sub.2 is alkyl of C.sub.1 to C.sub.30, R.sub.3 and R.sub.4 are each hydrogen or methyl, R.sub.5 is glycidyl, X is ether linkage (--O--) or ester linkage ##STR2## m and n are integers of 1 to 20.

Abstract: A method of producing carbon fibers in which an exhaust gas generated in a heat-treating stage of the production of carbon fibers is divided into two portions, one portion thereof being decomposed by the action of an oxidizing catalyst and subsequently being blended with the other portion, to be reused. According to said method, the heat loss in the exhaust gas disposal process can be substantially reduced and the efficiency of heat-treating can be improved and in consequence, various troubles due to the decomposed products contained in the heat-treating atmosphere such as surface damage, fuzziness and individual fiber breakage, etc. can be avoided.

Abstract: An improved process for manufacturing high-grade and high-quality graphite fibers by the steps of (a) heating carbon fibers from acrylic fibers in an initial heating zone while exposed to an atmosphere of inert gas having a maximum temperature from about 1700.degree. C. to 1900.degree. C., and (b) then heating the resulting fibers in a subsequent heating zone while exposed to an atmosphere of inert gas having a maximum temperature from 2300.degree. C. to 2700.degree. C.

Abstract: Disclosed is an improvement in a process for producing oxidized fibers wherein precursor fibers comprised of oxidizable continuous filaments are repeatedly brought into or out of contact with the surface of a heated body, maintained at a temperature of from approximately 200.degree. to 400.degree. C., in an oxidizing gaseous atmosphere thereby to be oxidized. The oxidized fibers can then be heated in a non-oxidizing gaseous atmosphere maintained at a temperature of at least approximately 800.degree. C. to produce carbon fibers, if desired. The improvement resides in that an interlaced filament yarn is used as the precursor fibers, which yarn substantially has no crimps or loops and is comprised of continuous filaments entangled with each other along the longitudinal direction thereof to an extent such that the coherency factor of the yarn is in the range of from approximately 20 to 100.