Electrostatic printer

Claim 2

In a photocopying machine having an imaging station for exposing a light-sensitive copy sheet to a projected image while the copy sheet is maintained stationary, the combination comprising endless belt means for carrying a light-sensitive copy sheet past the imaging station, mounting means for mounting said endless belt means for movement in a substantially straight line past the imaging station, said mounting means including two spaced shaft means rotatably supported in spaced apart relation and parallel to each other, drive means releasably coupled to one of said shaft means for driving said shaft means to move said endless belt means past the imaging station, means to impart a pressure differential onto the light-sensitive copy sheet being transported past the imaging station to hold the copy sheet on said endless belt means, stop means adjacent said endless belt means and operable in response to engagement by the copy sheet at the imaging station for releasing the coupling of said drive means to said shaft means, and brake means operable on one of said shaft means in response to the operation of said stop means for stopping the movement of said endless belt means past the imaging station to accurately position a copy sheet at the imaging station.

Claim 3

A photocopying machine according to claim 1, wherein said means to impart a pressure differential onto the light-sensitive copy sheet comprises means defining a vacuum chamber located between said spaced shaft means and inside the endless belt means carried by said shaft means, said means defining said vacuum chamber including a surface extending substantially parallel with the endless belts at the imaging station with perforations formed therein and opening toward said imaging station to enable air to be drawn therethrough to hold a light-sensitive copy sheet against said endless belt means, and said endless belt means having perforations formed therein to enable air to flow therethrough into said vacuum chamber.

Claim 4

A photocopying machine according to claim 2, wherein said mounting means are arranged for mounting said endless belt means for movement past a generally vertical imaging station with one of said shaft means being located beneath said means defining a vacuum chamber, said drive means being releasably coupled to said shaft means located beneath said vacuum chamber means, said other shaft means being located above said vacuum chamber means, and said brake means being operable on said other shaft means.

Claim 5

A photocopying machine according to claim 3, the combination further comprising removal means carried by said shaft means located beneath said vacuum chamber means for urging the copy sheet being carried by said endless belts away from the perforated surface of said endless belt means.

Claim 6

An electrostatic photocopy machine having an exposure station and a copy sheet imaging station spaced from said exposure station, and a vacuum sheet transport assembly of the type wherein a pressure differential is utilized to retain a sheet member against a backing member comprising: a. a housing member in said machine; b. a vacuum chamber carried by said housing and having a perforated front plate thereon; c. means for feeding a copy sheet toward said chamber; d. drive means on said housing, including a drive roller positioned above the chamber and a driven roller positioned below the chamber; e. spaced apart perforated belts interconnecting said rollers, said belts being positioned to pass across the perforated front plate of said vacuum chamber; f. adjustable stop means positioned between said belts and engaged by the leading edge of said copy sheet to disengage the drive means; g. brake means activated by said stop means and engaging said drive roller to prevent overtravel of said copy sheet after contact with said stop means, said brake means cooperating with said adjustable stop means to provide an accurate positioning of said copy sheet in front of said vacuum chamber; and h. removal means carried by said driven roller between the belts to urge said sheet member away from said belts.

Claim 7

An electrostatic photocopy machine having an exposure station and a copy sheet imaging station spaced from said exposure station, and a vacuum sheet transport assembly of the type wherein a pressure differential is utilized to retain a sheet member against a backing member comprising: a. a housing member in said machine; b. a vacuum chamber carried by said housing and having a perforated front plate thereon; c. means for feeding a copy sheet toward said chamber; d. drive means on said housing, including a drive roller positioned above the chamber and a driven roller positioned below the chamber; e. spaced apart perforated belts interconnecting said rollers, said belts being positioned to pass across the perforated front plate of said vacuum chamber; f. adjustable stop means positioned between said belts and engaged by the leading edge of said copy sheet to disengage the drive means; g. brake means activated by said stop means and engaging said drive roller to prevent overtravel of said copy sheet after contact with said stop means, said brake means cooperating with said adjustable stop means to provide an accurate positioning of said copy sheet in front of said vacuum chamber; and h. removal means carried by said driven roller between the belts to urge said sheet member away from said belts.

Claim 8

In a photocopying machine capable of handling different lengths of light-sensitive copy sheets, the combination comprising a magazine for containing a supply of copy paper sheets, another magazine for containing another supply of copy paper sheets, each of said magazines having a floor therein and a pair of adjustable side rails slidably associated therewith and having detent means associated with said floor to locate one of said side rails in one of two given positions, at least one of said magazines being removable from said photocopying machine for replenishing the supply of copy paper sheets in said magazines, sheet feeding means associated with each of said magazines including a pair of feed rollers adjustably mounted on a shaft having a polygonal cross-section for feeding the topmost sheet in each of said magazines into the photocopying machine, and means for selectively activating one of said sheet feeding means for supplying sheets from one of said magazines into said photocopying machine.

Claim 9

In a photocopying machine capable of handling different lengths of light-sensitive copy sheets, the combination comprising a magazine for containing a supply of copy paper sheets, another magazine for containing another supply of copy paper sheets, each of said magazines having a floor therein and a pair of adjustable side rails slidably associated therewith and having detent means associated with said floor to locate one of said side rails in one of two given positions, at least one of said magazines being removable from said photocopying machine for replenishing the supply of copy paper sheets in said magazines, sheet feeding means associated with each of said magazines including a pair of feed rollers adjustably mounted on a shaft having a polygonal cross-section for feeding the topmost sheet in each of said magazines into the photocopying machine, and means for selectively activating one of said sheet feeding means for supplying sheets from one of said magazines into said photocopying machine.

Claim 10

A photocopying machine according to claim 6, the combination further comprising copy sheet level sensing means associated with each of said magazines for sensing the height of the supply of copy sheets in each of said magazines, and said copy sheet level sensing means being operable in response to the supply of copy sheets in One of said magazines diminishing beneath a given height for selectively deactivating the particular copy sheet feeding means associated with that magazine and for providing a visual signal.

Claim 11

In a photocopying machine capable of handling different lengths of light-sensitive copy sheets, the combination comprising a magazine for containing a supply of copy paper sheets, sheet feeding means associated with said magazine for feeding the topmost sheet in said magazine into the photocopying machine, another magazine for containing another supply of copy paper sheets, another sheet feeding means associated with said other magazine for feeding the topmost sheet in said magazine into the photocopying machine, and means for selectively activating one of said sheet feeding means for supplying sheets from one of said magazines into said photocopying machine, and further comprising support means carried by each of said magazines for centrally engaging the underside of the leading sheet of a stack of copy paper sheets placed therein.

Claim 12

In a photocopying machine capable of handling different lengths of light-sensitive copy sheets, the combination comprising a magazine for containing a supply of copy paper sheets, sheet feeding means associated with said magazine for feeding the topmost sheet in said magazine into the photocopying machine, another magazine for containing another supply of copy paper sheets, another sheet feeding means associated with said other magazine for feeding the topmost sheet in said magazine into the photocopying machine, and means for selectively activating one of said sheet feeding means for supplying sheets from one of said magazines into said photocopying machine, and further comprising support means carried by each of said magazines for centrally engaging the underside of the leading sheet of a stack of copy paper sheets placed therein.

Claim 13

In an electrostatic printing machine capable of handling various sizes of copy sheet material: a. a plurality of copy sheet feed magazines, each of magazines having a floor therein and a pair of adjustable side rails slidably associated therewith; b. detent means associated with said floor to locate one of said side rails in one of two given positions with respect to said magazine floor; c. sheet feed means associated with each magazine including a pair of feed rollers which contact the top sheet of a copy sheet stack to feed the top sheet of said stack into the printing machine; d. means for selectively activating one of said sheet feed means; e. copy sheet level sensing means associated with said magazines to sense the height of the copy sheet supply in each magazine and to selectively deactivate the respective copy sheet feed means when said copy sheet supply in that magazine diminishes below a give height; and f. sheet engaging means carried by said side rails above the floor for engaging the front edges of said copy sheets to inhibit double feeding of copy sheets.

Claim 14

In an electrostatic printing machine capable of handling various sizes of copy sheet material: a. a plurality of copy sheet feed magazines, each of magazines having a floor therein and a pair of adjustable side rails slidably associated therewith; b. detent means associated with said floor to locate one of said side rails in one of two given positions with respect to said magazine floor; c. sheet feed means associated with each magazine including a pair of feed rollers which contact the top sheet of a copy sheet stack to feed the top sheet of said stack into the printing machine; d. means for selectively activating one of said sheet feed means; e. copy sheet level sensing means associated with said magazines to sense the height of the copy sheet supply in each magazine and to selectively deactivate the respective copy sheet feed means when said copy sheet supply in that magazine diminishes below a give height; and f. sheet engaging means carried by said side rails above the floor for engaging the front edges of said copy sheets to inhibit double feeding of copy sheets.

Claim 15

An electrostatic printing machine according to claim 9 having support means carried by each said magazine floor to centrally engage the underside of the leading edge of a stack of copy sheets placed therein.