GB1207799A - Improvements relating to photographic processing apparatus - Google Patents

Abstract

1,207,799. 799. Photographic processing apparatus. POLAROID CORP. April 17, 1969 [April 22, 1968], No.19742/69. Heading G2A. Apparatus for applying an accurately predetermined quantity of a liquid reagent uniformly to a succession of areas of sheet material 52 comprises a body including end and side walls defining a well 18 for containing a liquid reagent; a cylindrical roll 14 mounted for rotation about its axis within the well with an upper portion of the roll projecting above the well; one of the side walls including at least a portion having a cylindrical surface 27 located in parallel spaced relation to the peripheral surface of the roll, extending upwardly from beneath the roll at least to a horizontal plane through the axis of the roll and co-operating with the surface of the roll to define a channel 27 extending upwardly from beneath the roll; means for rotating the roll in a direction such that liquid is carried upwardly into the channel, the spacing between the cylindrical surface and the roll being such that the channel serves to meter the quantity of liquid carried upwardly on the surface of the roll during rotation thereof; and means 48 for guiding sheet material across the well in contact with a a portion of the surface of the roll moving in a direction opposite to the direction of movement of the sheet. The rotation of the roll entrains liquid between the sheet and the roll to form a meniscus 54. The surface of the roll is textured, e.g. with circumferential grooves to increase the quantity of liquid entrained. The roll and guide plate is provided with a hinged cover, a part 46 thereof co-operating with a curved support surface 34 to form a convergent passage for guiding the leading edge of a sheet into the applicator.