Moistening apparatus and method for duplicator sheets

Claim 2

Moistening apparatus for duplicator sheets, comprising, in combination, applicator means including a liquid absorbent means, and adapted to apply a moistening liquid to successive duplicator sheets so that the moisture content of said absorbent means is decreased by transfer of said liquid to the sheets; sensing means for sensing the moisture content of said absorbent means; motor means; control means controlled by said sensing means to start and stop said motor means depending on the sensed moisture content of said absorbent means; and movable supply means for said liquid driven by said motor means for supplying said liquid to said absorbent means when the sensed moisture content decreases below a predetermined minimum so thAt the sheets are maintained at a substantially constant moisture content.

Claim 3

Duplicator moistening apparatus for moistening duplicator copy sheets comprising, in combination, applicator means including a liquid absorbent means, and adapted to apply a moistening liquid contained in said absorbent means to successive duplicator sheets so that the moisture content of said absorbent means is decreased by transfer of said liquid to said duplicator copy sheets, said absorbent means having an electric resistance dependent on the moisture content thereof; sensing means including two spaced electrodes in contact with said absorbent means for sensing the resistance of the portion of said absorbent means for sensing the resistance of the portion of said absorbent means between said two spaced electrodes; motor means; control means controlled by said sensing means depending on the resistance and the moisture content of said portion of said absorbent means to start and stop said motor means when said moisture content is a predetermined minimum and maximum, respectively; and movable supply means for said liquid driven by said motor means to supply said liquid to said absorbent means when the sensed moisture content decreases below said predetermined minimum, and to stop with said motor means when the moisture content is increased to said predetermined maximum whereby said copy sheets are substantially uniformly moistened.

Claim 4

Duplicator moistening apparatus for moistening duplicator copy sheets comprising, in combination, applicator means including a liquid absorbent means, and adapted to apply a moistening liquid contained in said absorbent means to successive duplicator sheets so that the moisture content of said absorbent means is decreased by transfer of said liquid to said duplicator copy sheets, said absorbent means having an electric resistance dependent on the moisture content thereof; sensing means including two spaced electrodes in contact with said absorbent means for sensing the resistance of the portion of said absorbent means for sensing the resistance of the portion of said absorbent means between said two spaced electrodes; motor means; control means controlled by said sensing means depending on the resistance and the moisture content of said portion of said absorbent means to start and stop said motor means when said moisture content is a predetermined minimum and maximum, respectively; and movable supply means for said liquid driven by said motor means to supply said liquid to said absorbent means when the sensed moisture content decreases below said predetermined minimum, and to stop with said motor means when the moisture content is increased to said predetermined maximum whereby said copy sheets are substantially uniformly moistened.

Claim 5

Apparatus as claimed in claim 2, wherein said control means are electronic control means; and wherein said motor means includes an electric motor connected with and started and stopped, respectively, by said electronic control means when the current flowing between said electrodes is a predetermined minimum and maximum current, respectively, due to reduced and increased moisture content, respectively, and correspondingly increased and reduced resistance, respectively, of said portion of said absorbent means.

Claim 6

Apparatus as claimed in claim 2, wherein said supply means include a means for spraying the moistening liquid onto said absorbent means; and a pump driven by said motor means for pumping said liquid to said spraying means.

Claim 7

Apparatus as claimed in claim 2 wherein said applicator means include insulating container means supporting said absorbent means and said sensing means; and wherein said supply means are at least partly located in said container means for supplying liquid to said absorbent means.

Claim 8

Apparatus as claimed in claim 2 wherein said absorbent means includes an absorbent pad in contact with transported sheets; and comprising transporting roller means for transporting the sheets.

Claim 9

Apparatus as claimed in claim 2 wherein said applicator means include a transporting roller for transporting the sheets while rolling on the surface of the sheets, and wherein said absorbent means include an absorbent pad slidingly abutting said transporting roller so that said transporting roller is moistened by said liquid and transfers said liquid to the sheets.

Claim 10

Apparatus as claimed in claim 2 wherein said supply means include a pump driven by said motor means for pumping said moistening liquid onto said absorbent means when the sensed moisture content is insufficient.

Claim 11

Apparatus as claimed in claim 2 wherein said supply means include a container for said moistening liquid, an elevator roller partly immersed in the liquid in said container, and a transfer roller in rolling contact with said elevator roller and in sliding contact with said absorbent means; and wherein said motor drives said elevator roller when the sensed moisture content of the absorbent means is insufficient.

Claim 12

Apparatus as claimed in claim 9 wherein said container is closed and envelopes said elevator roller, said transfer roller, and the part of said absorbent means engaged by said transfer roller, and includes means for maintaining a pre-determined highest level of said moistening liquid in said container so that said absorbent means and said transfer roller are located above said constant level.

Claim 13

Apparatus as claimed in claim 2 wherein said motor means includes an electric motor, and circuit means connecting said motor with said control means; and a variable resistor in said circuit means for adjusting the maximum and minimum currents supplied to said control means for stopping and starting said motor.

Claim 14

Apparatus as claimed in claim 11 wherein said circuit means include a switch for stopping and starting said motor by disconnecting and connecting, respectively, said motor from and to a source of voltage.

Claim 15

Apparatus as claimed in claim 2 wherein said absorbent means includes a pad consisting of fibrous felt; and wherein said two spaced electrodes abut said felt pad, and circuit means connecting said electrodes with said electric control means.

Claim 16

A moistening method for duplicator sheets comprising electrically sensing the moisture content of a liquid absorbent pad while said pad transfers absorbed liquid to a roller rolling on duplicator sheets for moistening the same; and automatically supplying under the control of said sensing means replenishing liquid to said pad when the sensed moisture content is insufficient, so as to maintain a substantially constant moisture content in said absorbent pad.

Claim 17

A moistening method for duplicator sheets comprising electrically sensing the moisture content of a liquid absorbent pad while said pad transfers absorbed liquid to a roller rolling on duplicator sheets for moistening the same; and automatically supplying under the control of said sensing means replenishing liquid to said pad when the sensed moisture content is insufficient, so as to maintain a substantially constant moisture content in said absorbent pad.