Fluid droplet printer

Claim 2

A fluid droplet printer comprising: means for projecting a stream of writing fluid in the form of a succession of spaced discrete droplets along a path toward the surface of a record member; means for effecting relative movement between the record member and said projecting means; means for establishing an electric field through which the succession of droplets pass during their flow along said path from the projecting means to said record member; charging means for depositing a constant equal charge on said droplets at spaced locations along their path of travel through said electric field; and means controlled by input data to be printed for rendering said charging means effective to charge at least some of said droplets, said electric field being effective to deflect charged droplets from their path by an amount dependent upon the distance a droplet travels from the time it is charged until it strikes said record member whereby the charged droplets are deposited on said record member to produce a record representing the input data to be printed.

Claim 3

A fluid droplet printer comprising: means for projecting a stream of writing fluid in the form of a succession of spaced discrete droplets along a path toward the surface of a record member; means for effecting relative movement between the record member and said projecting means; means for establishing an electric field through which the succession of droplets pass during their flow along said path from the projecting means to said record member; a plurality of charging elements disposed at spaced locations along the path of droplet travel through said electric field for depositing a constant equal charge on said droplets; and charging circuit means controlled by input data to be printed for rendering said charging elements effective to charge at least some of said droplets, said electric field being effective to deflect charged droplets from their path by an amount dependent upon the distance a droplet travels from the time it is charged until it strikes said record member whereby the charged droplets are deposited on said record member to produce a record representing the input data to be printed.

Claim 4

A fluid droplet printer comprising: means for projecting a stream of writing fluid in the form of a succession of spaced discrete droplets along a path toward the surface of a record member; means for effecting relative movement between the record member and said projecting means; means for establishing an electric field through which the succession of droplets pass during their flow along said path from the projecting means to said record member; a plurality of charging elements disposed at spaced locations along the path of droplet travel through said electric field for depositing a constant equal charge on said droplets; and charging circuit means controlled by input data to be printed for rendering said charging elements effective to charge at least some of said droplets, said electric field being effective to deflect charged droplets from their path by an amount dependent upon the distance a droplet travels from the time it is charged until it strikes said record member whereby the charged droplets are deposited on said record member to produce a record representing the input data to be printed.

Claim 5

A fluid droplet printer as in claim 2 wherein said charging elements comprises a row of spaced apart charging pins which are contacted by uncharged droplets as they flow along said path.

Claim 6

A fluid droplet printer as in claim 3 and including synchronization means for synchronizing the charging of said pins with the arrival of the droplets at the pins.

Claim 7

A fluid droplet printer as in claim 3 including droplet collection means and wherein the last charging pin in said row charges all droplets which have not been deflected for printing, said electric field being effective to deflect the droplets charged by the last pin to said collection means.

Claim 8

A fluid droplet printer comprising: means for projecting a stream of writing fluid in the form of a succession of spaced discrete droplets along a path toward the surface of a record member; means for effecting relative movement between the record member and said projecting means; means for establishing an electric field through which the succession of droplets pass during their flow along said path from the projecting means to said record member; a plurality of charging elements disposed at spaced locations along the path of droplet travel through said electric field for depositing a constant equal charge on said droplets; a source of constant charging voltage for said charging elements; switching means for applying said charging voltage to said charging elements; and means controlled by input data to be printed for operating said switching means whereby said charging elements are rendered effective to charge at least some of said droplets, said electric field being effective to deflect charged droplets from their path by an amount dependent upon the distance a droplet travels from the time it is charged until it strikes said record Member whereby the charged droplets are deposited on said record member to produce a record representing the input data to be printed.

Claim 9

A fluid droplet printer comprising: means for projecting a stream of writing fluid in the form of a succession of spaced discrete droplets along a path toward the surface of a record member; means for effecting relative movement between the record member and said projecting means; means for establishing an electric field through which the succession of droplets pass during their flow along said path from the projecting means to said record member; a plurality of charging elements disposed at spaced locations along the path of droplet travel through said electric field for depositing a constant equal charge on said droplets; a source of constant charging voltage for said charging elements; switching means for applying said charging voltage to said charging elements; and means controlled by input data to be printed for operating said switching means whereby said charging elements are rendered effective to charge at least some of said droplets, said electric field being effective to deflect charged droplets from their path by an amount dependent upon the distance a droplet travels from the time it is charged until it strikes said record Member whereby the charged droplets are deposited on said record member to produce a record representing the input data to be printed.

Claim 10

A fluid droplet printer comprising: means for projecting a stream of writing fluid in the form of a succession of spaced discrete droplets along a path toward the surface of a record member; means for effecting relative movement between the record member and said projecting means; means for establishing an electric field through which the succession of droplets pass during their flow along said path from the projecting means to said record member; a row of spaced apart charging pins located along the path of droplet travel through said electric field and which are contacted by uncharged droplets as they flow along said path; a source of constant charging voltage for said charging pins; electric switches associated with the charging pins and operable to effect application of said charging voltage to said pins; and storage means associated with said electronic switches and responsive to input data to be printed, the outputs from said storage means operating the electronic switches whereby said charging pins are rendered effective to charge at least some of said droplets, said electric field being effective to deflect charged droplets from their path by an amount dependent upon the distance a droplet travels from the time it is charged until it strikes said record member whereby the charged droplets are deposited on said record member to produce a record representing the input data to be printed.

Claim 11

A fluid droplet printer comprising: means for projecting a stream of writing fluid in the form of a succession of spaced discrete droplets along a path toward the surface of a record member; means for effecting relative movement between the record member and said projecting means; means for establishing an electric field through which the succession of droplets pass during their flow along said path from the projecting means to said record member; a row of spaced apart charging pins located along the path of droplet travel through said electric field and which are contacted by uncharged droplets as they flow along said path; a source of constant charging voltage for said charging pins; electric switches associated with the charging pins and operable to effect application of said charging voltage to said pins; and storage means associated with said electronic switches and responsive to input data to be printed, the outputs from said storage means operating the electronic switches whereby said charging pins are rendered effective to charge at least some of said droplets, said electric field being effective to deflect charged droplets from their path by an amount dependent upon the distance a droplet travels from the time it is charged until it strikes said record member whereby the charged droplets are deposited on said record member to produce a record representing the input data to be printed.

Claim 12

A fluid droplet printer as in claim 7 including gutter means and a gutter charging pin located at the end of said row and connected to said charging voltage source whereby it will charge all droplets which have not been deflected for printing, said electric field being effective to deflect the droplets charged by the gutter pin into said gutter means.

Claim 13

A fluid droplet printer as in claim 7 wherein said electric field is established by a pair of spaced apart electrostatic deflection plates between which said succession of droplets pass, said plates being connected to a constant high voltage charge which produces a constant high voltage electric field between the plates.

Claim 14

A fluid droplet printer as in claim 9 wherein a virtual electrical ground plane exists between said deflection plates and the flow path of uncharged droplets is coincident with said plane.

Claim 15

A fluid droplet printer as in claim 7 including a hollow electrically grounded shield member located between said projecting means and said electric field and through which the succession of droplets pass.

Claim 16

In a fluid droplet printer the combination of: a nozzle for projecting a stream of writing fluid along a path toward the surface of a record member; means for supplying writing fluid under pressure to said nozzle; means for introducing regularly spaced varicosities in said stream of writing fluid to assure the formation of a succession of discrete droplets of uniform dimension and at a constant rate; means for effecting relative movement between the record member and said nozzle; a pair of spaced apart electrostatic deflection plates between which said succession of droplets pass along their path toward the record member; means for applying a constant electrostatic charge to said deflection plates to produce a constant electric field therebetween; a row of spaced apart charging elements located between said deflection plates and positioned along the path of droplet travel to make contact with said succession of droplets as they pass; a source of constant charging voltage for said charging elements; and means controlled by input data to be printed for applying said charging voltage to at least some of said charging elements whereby at least some of said droplets will receive a constant equal charge and said electric field will deflect said charged droplets from their path different amouNts for deposition at different positions on said record member to produce a record representing said input data.

Claim 17

In a fluid droplet printer the combination of: a nozzle for projecting a stream of writing fluid along a path toward the surface of a record member; means for supplying writing fluid under pressure to said nozzle; means for introducing regularly spaced varicosities in said stream of writing fluid to assure the formation of a succession of discrete droplets of uniform dimension and at a constant rate; means for effecting relative movement between the record member and said nozzle; a pair of spaced apart electrostatic deflection plates between which said succession of droplets pass along their path toward the record member; means for applying a constant electrostatic charge to said deflection plates to produce a constant electric field therebetween; a row of spaced apart charging elements located between said deflection plates and positioned along the path of droplet travel to make contact with said succession of droplets as they pass; a source of constant charging voltage for said charging elements; and means controlled by input data to be printed for applying said charging voltage to at least some of said charging elements whereby at least some of said droplets will receive a constant equal charge and said electric field will deflect said charged droplets from their path different amouNts for deposition at different positions on said record member to produce a record representing said input data.

Claim 18

The invention as set forth in claim 12 wherein the location of each charging element along said droplet path is related to a printing position on said record member.

Claim 19

The invention as set forth in claim 12 wherein the amount a charged droplet is deflected is dependent upon the location of the charging element that charged the droplet.

Claim 20

The invention as set forth in claim 12 wherein means are provided to feed said record member in a vertical direction and said deflection plates are arranged to deflect the charged droplets horizontally for deposition across said record member.

Claim 21

The invention as set forth in claim 12 wherein said charging elements take the form of pins which are approximately equally spaced apart.

Claim 22

The invention as set forth in claim 12 and including a gutter pipe and a gutter charging element positioned at the end of said row and connected to said constant charging voltage source to charge all droplets which have not been deflected for printing, said electric field deflecting into said gutter pipe those droplets charged by said gutter element.

Claim 23

The invention as set forth in claim 12 and including phase maintenance means for phasing the droplet charging voltage with respect to the time the droplets arrive at the charging elements.

Claim 24

The invention as set forth in claim 12 wherein a virtual electrical ground plane exists between said deflection plates and said nozzle is aimed so that the flow path of uncharged droplets is coincident with said plane.

Claim 25

In a fluid droplet printer the combination of: a nozzle for projecting a stream of writing fluid along a path toward the surface of a record member; means for supplying writing fluid under pressure to said nozzle; means for introducing regularly spaced varicosities in said stream of writing fluid to assure the formation of a succession of discrete droplets of uniform dimension and at a constant rate; means for effecting relative movement between the record member and said nozzle; a pair of spaced apart electrostatic deflection plates between which said succession of droplets pass along their path toward the record member; means for applying an electrostatic charge to said deflection plates to produce an electric field therebetween; a charging element located between said deflection plates and positioned in the path of droplet travel to make contact with said succession of droplets as they pass; a source of charging voltage for said charging element; and means controlled by input data to be printed for applying said charging voltage to said element whereby a droplet contacting the charged element will be charged and said electric field will deflect the charged droplet for deposition on said record member.

Claim 26

In a fluid droplet printer the combination of: a nozzle for projecting a stream of writing fluid along a path toward the surface of a record member; means for supplying writing fluid under pressure to said nozzle; means for introducing regularly spaced varicosities in said stream of writing fluid to assure the formation of a succession of discrete droplets of uniform dimension and at a constant rate; means for effecting relative movement between the record member and said nozzle; a pair of spaced apart electrostatic deflection plates between which said succession of droplets pass along their path toward the record member; means for applying an electrostatic charge to said deflection plates to produce an electric field therebetween; a charging element located between said deflection plates and positioned in the path of droplet travel to make contact with said succession of droplets as they pass; a source of charging voltage for said charging element; and means controlled by input data to be printed for applying said charging voltage to said element whereby a droplet contacting the charged element will be charged and said electric field will deflect the charged droplet for deposition on said record member.

Claim 27

In a fluid droplet printer the combination of: a nozzle for projecting a stream of writing fluid along a path toward the surface of a record member; means for supplying writing fluid under pressure to said nozzle; means for introducing regularly spaced variscosities in said stream of writing fluid to assure the formation of a succession of discrete droplets of uniform dimension and at a constant rate; means for effecting relative movement between the record member and said nozzle; a pair of spaced apart electrostatic deflection plates between which said succession of droplets pass along their path toward the record member; means for applying a constant electrostatic charge to said deflection plates to produce a constant electric field therebetween; a row of spaced apart charging pins located between said deflection plates and positioned along the path of droplet travel to make contact with said succession of droplets as they pass; a source of constant charging voltage for said charging pins; electronic switches in circuit with said charging pins, each switCh being operable to apply said charging voltage to an associated charging pin; and a shift register associated with each said electronic switch for operating same, said shift registers being controlled by input data to be printed to provide outputs for operating their associated switches to apply said charging voltage to at least some of said charging pins whereby at least some of said droplets will receive a constant equal charge and said electric field will deflect said charged droplets from their path different amounts for deposition at different positions on said record member to produce a record representing said input data.

Claim 28

In a fluid droplet printer the combination of: a nozzle for projecting a stream of writing fluid along a path toward the surface of a record member; means for supplying writing fluid under pressure to said nozzle; means for introducing regularly spaced variscosities in said stream of writing fluid to assure the formation of a succession of discrete droplets of uniform dimension and at a constant rate; means for effecting relative movement between the record member and said nozzle; a pair of spaced apart electrostatic deflection plates between which said succession of droplets pass along their path toward the record member; means for applying a constant electrostatic charge to said deflection plates to produce a constant electric field therebetween; a row of spaced apart charging pins located between said deflection plates and positioned along the path of droplet travel to make contact with said succession of droplets as they pass; a source of constant charging voltage for said charging pins; electronic switches in circuit with said charging pins, each switCh being operable to apply said charging voltage to an associated charging pin; and a shift register associated with each said electronic switch for operating same, said shift registers being controlled by input data to be printed to provide outputs for operating their associated switches to apply said charging voltage to at least some of said charging pins whereby at least some of said droplets will receive a constant equal charge and said electric field will deflect said charged droplets from their path different amounts for deposition at different positions on said record member to produce a record representing said input data.

Claim 29

The invention as set forth in claim 21 wherein each said shift register has a length which is related to the position of its associated charging pin along the pin row.

Claim 30

The invention as set forth in claim 21 and including logic circuit means controlled by the droplet formation rate and the charging of said pins to provide synchronizing pulses; and feedback means for supplying said synchronizing pulses to said shift registers to either delay or advance the time that the input data is applied to the charge pins so that the droplet charging voltage is phased with respect to the time the droplets arrive at the charge pins.

Claim 31

The invention as set forth in claim 21 wherein the charging pins are located to enable said electric field to produce droplet deflection amounts which differ in accordance with the predetermined printing positions on the record member.

Claim 34

A method as in claim 25 wherein the trajectory taken by a deflected charged droplet is dependent on when the droplet is charged as it passes along said row of charging elements.

Claim 35

A method as in claim 25 in which the application of the constant potential to the charging elements is synchronized with the arrival of the droplets at the elements.

Claim 36

A method as in claim 25 wherein all droplets not deflected for deposition on said record member are charged and deflected for collection.

Claim 39

A fluid droplet pRinter as in claim 9 wherein a virtual electrical plane exists between said deflection plates which is coincident with the flow path of uncharged droplets and a voltage source is provided which establishes a potential on said plane.