| 摘要 |
1,120,900. Printing processes. STANDARD TELEPHONES & CABLES Ltd. 19 Dec., 1966, No. 56619/66. Heading B6C. [Also in Division G2] In an electrographic apparatus wherein a drum or band carrying a latent electrostatic or magnetic image is passed through a powder applicator for developing the latent image, the powder applicator is provided by a fluid powder bed 4 supported on a fluid permeable membrane 2. Gas or liquid is supplied to a space 13 through a part 3. The powder particles may be agitated by blades or paddles (not shown), or by intermittently pumping gas or liquid into the bottom section 13 by a reciprocating pump. Alternatively, a flexible membrane (2), Fig. 2 (not shown) is actuated by a vibrator unit (7), air being admitted through a non-return valve 6. Excess powder forming background image areas may be removed by a vacuum system having a port (11), Fig. 3 (not shown) connected to a vacuum pump and filter. |
