摘要:
A method which permits easy fusion of commutator risers to armature coils of an electric motor. When there are 20 risers, for example, 10 through-holes are formed in the boss portion of the armature core of the motor, each through-hole being so sized that the back surfaces of two adjacent risers are exposed through each through-hole. Sub-electrodes are inserted into the through-holes such that each sub-electrode supports the back side of the two risers exposed through the through-hole which receives this sub-electrode. First and second main electrodes are so arranged that the first electrode contacts with the first riser of the first riser group exposed through the first through-hole while the second main electrode contacts the second riser of the sixth riser group exposed through the sixth through-hole. After conducting fusing on these risers, the main electrodes are shifted into contact with the risers which are the second as counted from the risers which have just been fused, and fusion is conducted on these risers. This operation is repeated until all the risers are fused.
摘要:
A fixing structure of the present invention is capable of fixing permanent magnets to an internal peripheral surface of a cylindrical yoke in a short time without producing a positional deviation. The fixing structure has magnet receiving pieces which are projected on the internal peripheral surface of an internal cylinder, and magnet holders each having elastically deformable magnet pressure pieces formed therein, so that permanent magnets are respectively held between the elastically deformed magnet pressure pieces and the magnet receiving pieces and pressed against the side of the magnet receiving pieces in a normal direction due to the elastic restoring force on the magnet pressure pieces. The permanent magnets can thus be integrally fixed to the internal peripheral surface of the internal cylinder.
摘要:
A casing of a motor is rendered light and also capable of forming a magnetic circuit in cooperation with a permanent magnet. The casing consists of an outer cylinder and an end bracket each being made of aluminum. An inner cylinder, made of iron and carrying a permanent magnet fixed to the inner peripheral surface thereof, is integrally fitted on the inner peripheral surface of a cylindrical portion of the outer cylinder which is sealed by the end bracket.
摘要:
Provided is a process for producing pitch carbon fibers by subjecting pitch fibers obtained by melt-spinning a carbonaceous pitch to infusibilization treatment and then to carbonization treatment or both carbonization treatment and subsequent graphitization treatment, characterized in that a dimethyl polysiloxane having a viscosity at 25.degree. C. in the range of 12,000 to 1,000,000 cSt is applied to the fibers after the infusibilization treatment, and the infusibilized fibers with the dimethyl polysiloxane thus applied thereto are then subjected to the carbonization treatment or both the carbonization treatment and the subsequent graphitization treatment.
摘要:
In the process for producing pitch carbon fibers by melt-spinning a carbonaceous pitch, and infusiblizing the resulting pitch fibers followed by carbonization and, additionally as needed, graphitization, the pitch fibers are subjected to infusiblization treatment following application of a dimethyl polysiloxane having a viscosity at 25.degree. C. in the range between 0.5 and 500 cSt and removing said dimethyl polysiloxane by washing prior to the carbonization.
摘要:
Provided is a process for producing a pitch-based graphite fiber, which process comprises treating a pitch fiber in an oxidative gas atmosphere to render it infusible, said pitch fiber being obtained by melt-spinning a carbonaceous pitch, then heat-treating the infusibilized fiber at 400.degree.-750.degree. C. in an inert gas atmosphere to obtain a precarbonized fiber substantially containing oxygen, then raising the temperature to 2,000.degree.-3,000.degree. C. at a rate of 500.degree. C. or higher per minute in an inert gas atmosphere and heat-treating the precarbonized fiber at the raised temperature of 2,000.degree.-3,000.degree. C. in said inert gas atmosphere.