Abstract: A multicolor electrophotography apparatus for forming a color image on a rotatable photosensitive device shaped cylindrically and arranged to hold on its circumferential surface an electrostatic image optically formed by an exposing device. The apparatus includes a plurality of developing devices movably provided along the circumference of the photosensitive device for developing a plurality of different-color toner images overlapping each other. Each of the developing devices is selectively driven to take a developing position and a non-developing position, each of the developing devices being closed to photosensitive devices up to the developing position and being separated therefrom up to the non-developing position. When the exposing device is in the non-operated state, at least one of the developing devices takes the developing position and the other developing devices take the non-developing positions.

Abstract: A developing device for developing a latent electrostatic image for an electrophotographic copying machine includes a cylindrical resilient body such as a fur brush or a roller of sponge for triboelectrically uniformly charging a single component developer of the dry type supplied from a developer storage casing and for coating the developer as a uniform thin layer on a developer carrier such as a developing roller.

Abstract: A cleaning device for use in a color electrophotographic apparatus in which a photosensitive medium is made to rotate for a plurality of times so as to conduct repetitional cycles each including charging, exposure and development, thereby forming toner images of different colors on the photosensitive medium. The cleaning device comprises a conductive fur brush for cleaning the surface of the photosensitive medium so as to remove any toner remaining on the surface of the photosensitive medium; and a driving mechanism for placing the fur brush in contact with the photosensitive medium during cleaning and for keeping the same away from the photosensitive medium when the cleaning is not conducted. The cleaning device effectively prevents any part of the toner after the transfer from remaining on the surface of the photosensitive medium.

Abstract: An apparatus wherein a thermoluminescent type radiation dosimeter is heated and thermoluminant rays emitted from the dosimeter are measured. It is constructed in such manner that to perform the measurement a personal identification card must be inserted to the apparatus. The mark on the dosimeter and the mark on the identification card are collated, and only when they coincide with each other is the measurement performed.

Abstract: A readout instrument comprising a heating device such as a multi-nozzle hot air blower for individually heating a plurality of thermoluminescence dosimeter elements, a photoelectric transducer, an optical guide for efficiently condensing the luminescence ray on the photosensitive face of the transducer, and a thermal radiation shield plate with slits in the same number as the dosimeter elements to minimize errors in the readout attributable to heat radiation from heated bodies such as components of the heating device.