Cassette type feed apparatus
AssigneeMinolta Camera Kabushiki Kaisha
InventorTateomi Kono
Life of this patent
Estimating the term…
Abstract
A paper feed mechanism employing interchangeable cassettes having liftable paper stack support plates and containing different size paper sheets includes a feed roll engaging the uppermost sheet of an operatively positioned cassette, a lifting member separably engaging the support plate and a spring system biasing the lifting member and adjustable under the control of an indexing member on the operative cassette to adjust the bias in accordance with the paper size so that the pressure of the feed roll in the uppermost sheet is constant and independent of paper size. The spring system may include a first spring which is operable with all sizes of paper sheet and a second spring which is enabled only when the cassette contains large sheets and biases the lifting member with the first spring.
Claims6
A paper feed mechanism comprising a feed roll, an interchangeable cassette including a support member disposed in said cassette and supporting a stack of paper sheets for upward movement, biasing means urging said stack upwardly to advance the uppermost sheet of said stack into feed engagement with said feed roll and means for adjusting said biasing means including an indexing member disposed on said cassette in accordance with the weight per unit height of the paper contained therein and means responsive to the disposition of said indexing member for varying said biasing means whereby to regulate the pressure of said uppermost sheet on said feed roll to a substantially constant predetermined value.
In a paper feed apparatus which is loadable with a cassette which is interchangeable with another cassette, said cassette having a paper support plate in its main body accommodating sheets of paper as stacked on the support plate and in which the paper support plate is liftable to press the stack of sheets against feed rollers, the improvement comprising:
- a lifting member for lifting the paper support plate;
- biasing means including a spring member for providing a lifting force to the lifting member, and
- adjusting means for varying the force of the biasing means and including cam members provided on each cassette and engageable with said spring member when a respective cassette is loaded the sizes of the cam members being different from each other in accordances with differences in the weight of the stack of sheets on the paper support plate.
Dependencies are inferred from the claim text.