US 5,501,444 A · Sheet supply apparatus

Abstract

The present invention provides a sheet supply apparatus comprising a lifter device for maintaining a height of an upper surface of a sheet stack supported by a sheet supporting device substantially constant by lifting or lowering the sheet supporting device, and a supply device for feeding out an uppermost sheet from the sheet stack maintained in a constant height position by the lifter device, and wherein the lifter device comprises a clutch member for transmitting a predetermined amount of rotation from a drive gear, a rock member for rocking a ratchet pawl by the rotation transmitted by the clutch member, a ratchet gear engageable by the ratchet pawl and rotated by a rocking movement of the ratchet pawl, a lifter member connected to the ratchet gear and adapted to lift the sheet supporting member by rotation of the ratchet gear, and an actuation device shifted in accordance with the height of the upper surface of the sheet stack rested on the sheet supporting device and adapted to actuate the clutch member when the height of the upper surface of the sheet stack is below a predetermined height.

Claims22

Dependent claims

A sheet supply apparatus comprising:

a lifter means for maintaining a height of an upper surface of a sheet stack supported by a sheet supporting means substantially constant by lifting or lowering said sheet supporting means;
and
a supply means for feeding out an uppermost sheet from the sheet stack maintained in a constant height position by said lifter means;
wherein said lifter means comprises:
a clutch means for transmitting a predetermined amount of rotation from a drive gear;
a rock means for rocking a ratchet pawl by the rotation transmitted by said clutch means;
a ratchet gear engageable by said ratchet pawl and rotated by a rocking movement of said ratchet pawl;
a lifter member connected to said ratchet gear to lift said sheet supporting member by rotation of said ratchet gear;
and
an actuation means shifted in accordance with the height of the upper surface of the sheet stack rested on said sheet supporting means to actuate said clutch means when the height of the upper surface of the sheet stack is below a predetermined height.

7 more elements

A sheet supply apparatus comprising:

a sheet supporting means for supporting a sheet and removably mounted to the sheet supply apparatus;
a supply means movable in an up-and-down direction to be abutted against an upper surface of the sheet rested on said sheet supporting means for feeding out the sheet at a supply position;
a shift means for lowering said supply means to abut said supply means against the upper surface of the sheet when the sheet is to be supplied and for lifting said supply means to a waiting position spaced apart from the upper surface of the sheet when the sheet is not supplied;
a rock means for rocking a ratchet pawl by rotation of a drive gear;
a ratchet gear engageable by said ratchet pawl and rotated by a rocking movement of said ratchet pawl;
a lifter member connected to said ratchet gear and adapted to lift said sheet supporting member by rotation of said ratchet gear;
an actuation means for driving said rock means in accordance with an abutment position between said supply means at said supply position and the sheet supported by said sheet supporting means;
a lock means for regulating movement of said shift means under a condition that said supply means is lowered in response to a mounting operation of said sheet supporting means to the sheet supply apparatus;
and
a lock releasing means for releasing the regulation of said lock means when the upper surface of
the sheet supported by said sheet supporting means is brought to a predetermined position by said lifter means.

8 more elements

Dependencies are inferred from the claim text.

Sheet supply apparatus

Life of this patent

Sheet supply apparatus

Life of this patent

Abstract

Claims22