Copy paper supply system for a transfer type electrostatic copying apparatus

Claim 1

In a copy paper supply system for use in a transfer type electrostatic copying apparatus and including spaced walls of a housing of the apparatus and a receiving member mounted between said spaced walls, the improvement wherein said system comprises: a cassette adapted to be inserted into and withdrawn from said receiving member mounted between said spaced walls, said cassette having a bottom, an open top, spaced opposite side walls, and spaced front and rear walls, said bottom in a forward end portion thereof an opening; a mounting plate positioned within said cassette for supporting a stack of copy paper sheets which are to be fed singly from said cassette along a copy paper path, said mounting plate having a trailing edge, with respect to said copy paper path, pivotally mounted to said bottom about an axis extending in a direction transverse to said copy paper path, said mounting plate having depending from a forward portion thereof a projection at a position to align with said opening; said cassette including a pair of claws for contacting forward portions of a topmost copy paper sheet, said claws being equally spaced from said projection on opposite sides thereof; a copy paper feeding shaft rotatably mounted in said spaced walls of the housing at a fixed position above said cassette, said shaft having spaced along the length thereof plural feeding rollers fixed to said shaft; a push up shaft pivotally journalled in said spaced walls of the housing, said push up shaft having fixed thereto a push up member for, upon pivotal movement of said push up shaft, movement between a feeding position, whereat said push up member extends upwardly through said opening into contact with said projection and pivots said mounting plate upwardly about said axis with respect to said cassette bottom and pivots a forward portion of said cassette upwardly with respect to said receiving member, thereby pressing the topmost copy paper sheet against said feeding rollers, and a non-feeding position, whereat said mounting plate rests on said bottom, said forward portion of said cassette is pivoted downwardly with respect to said receiving member, and the topmost copy paper sheet is spaced from said feeding rollers; support projection means depending from a trailing portion of said mounting plate for, when said mounting plate is pivoted upwardly with respect to said cassette bottom, balancing the pressure of contact of the topmost copy paper sheet against said feeding rollers; and means for, when said forward portion of said cassette is pivoted upwardly with respect to said receiving member, limiting the extent of such pivoting and preventing rearward movement of said cassette, said means comprising wedge-shaped notches formed in upper edges of said side walls of said cassette at said forward portion thereof, and retaining plates extending from said spaced walls of the housing, said retaining plates being received in said notches when said forward portion of said cassette is pivoted upwardly.