Abstract A sheet feeding device for an electrophotographic copying machine and the like has a flapping up member which protrudes through the bottom of a sheet feeding cassette to bring the sheets thereon into contact with a sheet feeding roller. The flapping up member is moved by a driven lever which is in turn moved by a low-tension biasing member in the direction of flapping the bottom plate up upon receipt of a sheet feeding commencement signal. A restrain member energized by a high-tension biasing member is provided to restrain the flapping up member to the retreated position upon termination of the sheet feeding commencing signal whereby the sheet feeding cassette is not affected by any resistance at the time of insertion or removal of the cassette and the bottom plate of the cassette is automatically flapped up only while sheet feeding is being operated.
In a sheet feeding means having a mechanism to flap up a bottom plate of a sheet feeding cassette loaded on to a sheet feeding table by means of a flapping-up member which is incorporated into said sheet feeding table, the improvement comprising: said flapping-up member being energized by a low tension biasing member in the direction of a flapping-up position, a restraining member energized by a high tension biasing member in the direction of restraining said flapping-up member at a retracted position in said sheet feeding table, and a sheet feeding drive for driving a sheet feeding operation in response to a sheet feeding signal, wherein said flapping-up member is restrained by said restraining member in said retracted position when no sheet feeding signal is given, and is released from said restraining member when the sheet feeding signal is given, whereby said flapping-up member is operated to flap up said bottom plate only during a sheet feeding operation.
Claim 2
Dependent Claim
159 words
In a sheet feeding means having a mechanism to flap up a bottom plate of a sheet feeding cassette loaded on to a sheet feeding table by means of a flapping-up member which is incorporated into said sheet feeding table, the improvement comprising: said flapping-up member being energized by a low tension biasing member in the direction of a flapping-up position, a restraining member energized by a high tension biasing member in the direction of restraining said flapping-up member at a retracted position in said sheet feeding table, and a sheet feeding drive for driving a sheet feeding operation in response to a sheet feeding signal, wherein said flapping-up member is restrained by said restraining member in said retracted position when no sheet feeding signal is given, and is released from said restraining member when the sheet feeding signal is given, whereby said flapping-up member is operated to flap up said bottom plate only during a sheet feeding operation.
Claim 3
Dependent Claim
56 words
The improvement as said forth in claim 1, wherein said sheet feeding drive includes a spring clutch, and said restraining member is energized to overcome said high tension biasing member in the direction of releasing said flapping-up member by engagement of said spring clutch of said sheet feeding drive in response to said sheet feeding signal.