Developing apparatus for photocopy machines

Claim 2

A developing apparatus for photocopy machines comprising, in combination, a developing chamber having an inlet for receiving developing medium, an outlet for discharging said developing medium, and means for transporting sensitized paper therethrough in the line of flow of developing medium from the inlet to the oulet; means for introducing developing medium into said developing chamber in controlled amounts via said inlet; and a vacuum pump in communication with said outlet to remove said developing medium from the developing chamber; said vacuum pump being adapted to pump a greater volume of developing medium from said developing chamber than is introduced thereto, to maintain the internal pressure of said developing chamber at below atmospheric, and thereby avoid external leakage of developing medium.

Claim 3

A developing apparatus in accordance with claim 1, in which the developing chamber includes a second outlet; and said means for introducing developing medium comprises a reservoir containing developing medium; means communicating said reservoir and the inlet of the developing chamber; and a pump connected at its suction side to the second outlet of the developing chamber and connected at its output side to the reservoir to circulate developing medium between the reservoir and the developing chamber.

Claim 4

A developing apparatus for photocopy machines compriSing, in combination, a developing chamber having an inlet for receiving developing medium, an outlet for discharging said developing medium, and means for transporting sensitized paper therethrough in the line of flow of developing medium from the inlet to the outlet; means for introducing developing medium into said developing chamber in controlled amounts via said inlet; and a vacuum pump in communication with said outlet to remove said developing medium from the developing chamber; said vacuum pump being adapted to pump a greater volume of developing medium from said developing chamber than is introduced thereto, to maintain the internal pressure of said developing chamber at below atmospheric, and thereby avoid external leakage of developing medium, and a pressure sensitive control means disposed in the developing chamber and responsive to the below atmosphere internal pressure thereof to permit the entry of ambient air when such internal pressure is reduced below a predetermined value.

Claim 5

A developing apparatus for photocopy machines compriSing, in combination, a developing chamber having an inlet for receiving developing medium, an outlet for discharging said developing medium, and means for transporting sensitized paper therethrough in the line of flow of developing medium from the inlet to the outlet; means for introducing developing medium into said developing chamber in controlled amounts via said inlet; and a vacuum pump in communication with said outlet to remove said developing medium from the developing chamber; said vacuum pump being adapted to pump a greater volume of developing medium from said developing chamber than is introduced thereto, to maintain the internal pressure of said developing chamber at below atmospheric, and thereby avoid external leakage of developing medium, and a pressure sensitive control means disposed in the developing chamber and responsive to the below atmosphere internal pressure thereof to permit the entry of ambient air when such internal pressure is reduced below a predetermined value.

Claim 6

A developing chamber in accordance with claim 3, in which said pressure sensitive means is a normally closed control valve communicating the interior and exterior of the developing chamber.

Claim 7

A developing apparatus for photocopy machines comprising, in combination, a developing chamber having an inlet for receiving developing medium, an outlet for discharging said developing medium, and means for transporting sensitized paper therethrough in the line of flow of developing medium from the inlet to the outlet; means for introducing developing medium into said developing chamber in controlled amounts via said inlet; and a vacuum pump in communication with said outlet to remove said developing medium from the developing chamber; said vacuum pump being adapted to pump a greater volume of developing medium from said developing chamber than is introduced thereto, to maintain the internal pressure of said developing chamber at below atmospheric, and thereby avoid external leakage of developing medium, and a vacuum surge chamber disposed in the line of flow from the outlet of the developing chamber to the inlet of the vacuum pump adapted to maintain a constant below atmosphere pressure within the developing chamber.

Claim 8

A developing apparatus for photocopy machines comprising, in combination, a developing chamber having an inlet for receiving developing medium, an outlet for discharging said developing medium, and means for transporting sensitized paper therethrough in the line of flow of developing medium from the inlet to the outlet; means for introducing developing medium into said developing chamber in controlled amounts via said inlet; and a vacuum pump in communication with said outlet to remove said developing medium from the developing chamber; said vacuum pump being adapted to pump a greater volume of developing medium from said developing chamber than is introduced thereto, to maintain the internal pressure of said developing chamber at below atmospheric, and thereby avoid external leakage of developing medium, and a vacuum surge chamber disposed in the line of flow from the outlet of the developing chamber to the inlet of the vacuum pump adapted to maintain a constant below atmosphere pressure within the developing chamber.

Claim 9

A developing apparatus in accordance with claim 5, in which the vacuum surge chamber comprises a sealed tank having an inlet in communication with the outlet of the developing chamber; an outlet in communication with the suction side of said vacuum pump; and a normally closed control valve communicating the interior and exterior of the tank, and responsive to the below atmospheric internal pressure of said tank to open when such internal pressure is reached below a predetermined valve to permit the entry of ambient air therein.

Claim 10

A developing apparatus in accordance with claim 6, in which the vacuum surge chamber maintains the below atmosphere pressure within the developing chamber at about 0.2 inches of water column to about 1.0 inches of water column.

Claim 11

A developing apparatus in accordance with claim 1, in which the output of the vacuum pump is in communication with an absorption vessel containing suitable material to absorb the discharged developing medium.

Claim 12

A developing apparatus for photocopy machines comprising, in combination, a developing chamber having an inlet for receiving developing medium, an outlet for discharging said developing medium, and means for transporting sensitized paper therethrough in the line of flow of developing medium from the inlet to the outlet; means for introducing developing medium into said developing chamber in controlled amounts via said inlet; and a vacuum pump in communication with said outlet to remove said developing medium from the developing chamber; said vacuum pump being adapted to pump a greater volume of developing medium from said developing chamber than is introduced thereto, to maintain the internal pressure of said developing chamber at below atmospheric, and thereby avoid external leakage of developIng medium, the output of the vacuum pump being in communication with a catalytic reactor to breakdown the discharged developing medium into its non-toxic components for exhausting into the surrounding atmosphere.

Claim 13

A developing apparatus for photocopy machines comprising, in combination, a developing chamber having an inlet for receiving developing medium, an outlet for discharging said developing medium, and means for transporting sensitized paper therethrough in the line of flow of developing medium from the inlet to the outlet; means for introducing developing medium into said developing chamber in controlled amounts via said inlet; and a vacuum pump in communication with said outlet to remove said developing medium from the developing chamber; said vacuum pump being adapted to pump a greater volume of developing medium from said developing chamber than is introduced thereto, to maintain the internal pressure of said developing chamber at below atmospheric, and thereby avoid external leakage of developIng medium, the output of the vacuum pump being in communication with a catalytic reactor to breakdown the discharged developing medium into its non-toxic components for exhausting into the surrounding atmosphere.

Claim 14

A developing apparatus in accordance with claim 8, in which the developing medium is anhydrous ammonia and the absorption material is citric acid.

Claim 15

A developing apparatus in accordance with claim 9, in which the developing medium is anhydrous ammonia and the catalytic reactor breaks down such ammonia into nitrogen gas and water vapor.

Claim 16

A developing apparatus for photocopy machines comprising, in combination, a developing chamber having an inlet for receiving developing medium, an outlet for discharging said developing medium, and means for transporting sensitized paper therethrough in the line of flow of developing medium from the inlet to the outlet; means for introducing developing medium into said developing chamber in controlled amounts via said inlet; and a vacuum pump in communication with said outlet to remove said developing medium from the developing chamber; said vacuum pump being adapted to pump a greater volume of developing medium from said developing chamber than is introduced thereto, to maintain the internal pressure of said developing chamber at below atmospheric, and thereby avoid external leakage of developing medium, said developing chamber including a second outlet; and said means for introducing developing medium comprising a reservoir containing developing medium; means communicating said reservoir and the inlet of the developing chamber; and a pump connected at its suction side to the second outlet of the developing chamber and connected at its output side to the reservoir to circulate developing medium between the reservoir and the developing chamber, said developing medium being anhydrous ammonia; the reservoir being sealed and containing a solution of aqueous ammonia and gaseous anhydros ammonia disposed thereabove; and the output side of the pump being in communication with the reservoir at a point below the surface of the aqueous ammonia, whereby the gaseous ammonia entering the reservoir from the pump is bubbled through said aqueous ammonia to facilitate the dissolution of the aqueous ammonia and thereby generate additional quantities of anhydrous ammonia, and to raise the pressure within the reservoir above that of the developing chamber to facilitate circulation of ammonia between the reservoir and the developing chamber.

Claim 17

A developing apparatus for photocopy machines comprising, in combination, a developing chamber having an inlet for receiving developing medium, an outlet for discharging said developing medium, and means for transporting sensitized paper therethrough in the line of flow of developing medium from the inlet to the outlet; means for introducing developing medium into said developing chamber in controlled amounts via said inlet; and a vacuum pump in communication with said outlet to remove said developing medium from the developing chamber; said vacuum pump being adapted to pump a greater volume of developing medium from said developing chamber than is introduced thereto, to maintain the internal pressure of said developing chamber at below atmospheric, and thereby avoid external leakage of developing medium, said developing chamber including a second outlet; and said means for introducing developing medium comprising a reservoir containing developing medium; means communicating said reservoir and the inlet of the developing chamber; and a pump connected at its suction side to the second outlet of the developing chamber and connected at its output side to the reservoir to circulate developing medium between the reservoir and the developing chamber, said developing medium being anhydrous ammonia; the reservoir being sealed and containing a solution of aqueous ammonia and gaseous anhydros ammonia disposed thereabove; and the output side of the pump being in communication with the reservoir at a point below the surface of the aqueous ammonia, whereby the gaseous ammonia entering the reservoir from the pump is bubbled through said aqueous ammonia to facilitate the dissolution of the aqueous ammonia and thereby generate additional quantities of anhydrous ammonia, and to raise the pressure within the reservoir above that of the developing chamber to facilitate circulation of ammonia between the reservoir and the developing chamber.

Claim 18

A developing apparatus in accordance with claim 2, in which the vacuum pump and the circulating pump for the developing medium are both driven by a single electrical motor.

Claim 19

A developing apparatus for diazo photocopy machines comprising, in combination, a developing chamber including transport means for advancing exposed diazo-type sensitized paper therethrough; means for introducing and circulating anhydrous ammonia within the chamber to develop an image on the sensitized paper; a vacuum pump for evacuating said anhydrous ammonia from the developing chamber; and a vacuum surge chamber disposed in the line of flow from the developing chamber to the vacuum pump; said vacuum pump being adapted to pump a greater volume of anhydrous ammonia from the developing chamber than is introduced thereon to maintain the internal pressure of said developing chamber at below atmospheric to avoid external leakage of ammonia fumes; and said vacuum surge chamber being adapted to maintain said below atmospheric pressure within the developing chamber at a relatively constant level.

Claim 20

A developing apparatus for diazo photocopy machines comprising, in combination, a developing chamber including transport means for advancing exposed diazo-type sensitized paper therethrough; means for introducing and circulating anhydrous ammonia within the chamber to develop an image on the sensitized paper; a vacuum pump for evacuating said anhydrous ammonia from the developing chamber; and a vacuum surge chamber disposed in the line of flow from the developing chamber to the vacuum pump; said vacuum pump being adapted to pump a greater volume of anhydrous ammonia from the developing chamber than is introduced thereon to maintain the internal pressure of said developing chamber at below atmospheric to avoid external leakage of ammonia fumes; and said vacuum surge chamber being adapted to maintain said below atmospheric pressure within the developing chamber at a relatively constant level.

Claim 21

A developing apparatus in accordance with claim 14, in which the vacuum surge chamber is sealed to the atmosphere, and includes a normally closed control valve communicating the interior and exterior thereof; said valve being responsive to the below-atmospheric pressure within the surge chamber to permit the entry of ambient air when such pressure is reduced below a predetermined value.

Claim 22

A developing apparaTus in accordance with claim 15, in which the valve maintains the below atmospheric pressure within the developing chamber within the range of about 0.2 inches to about 1.0 inches of water column.

Claim 23

A developing apparatus for photocopy machines comprising, in combination, a developing chamber having an inlet for receiving developing medium, an outlet for discharging said developing medium, and means for transporting sensitized paper through said developing chamber in the line of flow of developing medium from the inlet to the outlet, means for introducing developing medium into said developing chamber in controlled amounts via said inlet; a vacuum pump in communication with said outlet to remove said developing medium from the developing chamber, and means connected with said developing chamber maintaining the internal pressure of said developing chamber at lower than atmospheric pressure to thereby avoid external leakage of developing medium.

Claim 24

A developing apparatus for photocopy machines comprising, in combination, a developing chamber having an inlet for receiving developing medium, an outlet for discharging said developing medium, and means for transporting sensitized paper through said developing chamber in the line of flow of developing medium from the inlet to the outlet, means for introducing developing medium into said developing chamber in controlled amounts via said inlet; a vacuum pump in communication with said outlet to remove said developing medium from the developing chamber, and means connected with said developing chamber maintaining the internal pressure of said developing chamber at lower than atmospheric pressure to thereby avoid external leakage of developing medium.