US3435751A

US3435751A - Photocopy developing apparatus

Info

Publication number: US3435751A
Application number: US591822A
Authority: US
Inventors: Robert C Goodman; Emilio G Mastroianni
Original assignee: GAF Corp
Current assignee: R Q O HOLDING CO Inc
Priority date: 1966-11-03
Filing date: 1966-11-03
Publication date: 1969-04-01
Anticipated expiration: 1986-04-01
Also published as: NL6714928A; GB1142430A; DE1597682B2; DE1597682C3; DE1977683U; CH470696A; DE1597682A1

Description

April 1, 1869 R. c. GoQnMAN ETAL 3,435,751

I Paa'rocoPY DEVELOPING APPARATUS Piled Nov-` s; 196e 2o y A20' F lg INVENToRs Robert C. Goodman v Emilio G. Mastroianni ATTORNEY United States Patent 3,435,751 PHOTOCOPY DEVELOPING APPARATUS Robert C. Goodman, Binghamton, and Emilio G. Mastroianni, Endicott, N.Y., assignors to GAF Corporation, New York, N.Y., a corporation of Delaware Filed Nov. 3, 1966, Ser. No. 591,822 Int. Cl. G03d 3/12 U.S. Cl. 95-94 4 Claims ABSTRACT OF THE DISCLOSURE A photographic apparatus having a developing chamber and a mixing chamber for anhydrous and aqueous ammonia. A liquid vessel is connected to the mixing chamber and a pump connected to the liquid vessel establishes a predetermined liquid level in the mixing chamber. A blower is in communication with the mixing chamber and circulates a solution into the developing chamber. A heater system is provided in the developing and mixing chambers to maintain the proper temperatureof the solution.

The present invention relates to developing apparatus and more particularly to such apparatus in which exposed, sensitized material is contacted by a gaseous medium, such as an ammonia gas and water vapor mixture.

Certain rerpoduction processes use ammonia gas and water vapor mixtures to develop exposed images on sensitized webs of lm, plastics, paper or other gelatin coated materials. Diiculties have been experienced with transporting the material in the developing medium so that the material is uniformly contacted by the developing medium without leaving scratches or marks thereon caused by supports for the material itself. Further the supply of the medium must be uniform, and the concentration of the developing medium in the vapor phase, land its concentration with respect to water vapor which is added thereto, must remain in predetermined limits.

Briefly, in accordance with the present invention, the developing apparatus has a pair of chambers vertically spaced from one another. A material such as sensitive paper, which has been exposed, is fed by a pair of rollers having a suitable covering such as rubber or plastic, from an entrance into the area between the the chambers. A developing medium, such as an ammonia-water vapor mixture, is supplied from each chamber under pressure along the path of motion of the paper, to the upper and lower portions of the paper so that the paper is iloated on a developing medium as it moves from entrance to exit. Another pair of rollers, similar to the ones located at the entrance, are located at the exit to lead the developed paper from the area between the chambers.

The developing medium is drawn out of the area between the chambers by ducts located near the exit and is continuously recirculated by a blower which supplied it under some positive pressure to each of the chambers for distribution above and beneath the paper. A gas generator or mixer for the ammonia-water vapor mixture is provided which includes a closed vessel, supplied with a heater,to which either anhydrous or aqueous ammonia can be supplied. The closed vessel is connected to a water lvel vessel which in turn is connected to a water pump which establishes a level of water in the water vessel and thereby establishes a level of water in the closed vessel. The control of the mixture, that is, controlling the replacement of the water vapor and ammonia as it is removed from the gas generator, can of course be accomplished in accordance with other previously known arrangements, for example, using floats, chemical sensing controls and the like.

Accordingly, an object of the invention is to provide a developing apparatus in which sensitized material can be contacted by the developing medidum uniformly and over the entire area thereof.

Another object of the invention is to provide a developing apparatus in which the sensitized material is supported by the developing medium while being transported therethrough.

A further object of the invention is to provide a developing apparatus which can use either aqueous or anhydrous ammonia as the developing medium.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 illustrates the developing apparatus, partly broken away, partly in pictorial, and partly in schematic form;

FIG. 2 is a schematic sectional view along lines 2-2 of FIG. l, omitting unessential elements; and

FIG. 3 is a fragmentary sectional view along lines 3-3 of FIG. l.

Referring now to the drawings, wherein like reference characters designate like or corresponding parts throughout the several views, there is shown in FIGS. l and 2 a sheet of sensitized paper 10, which may be a cut sheet, or a continuous web from a roll, which is fed between a pair of

rollers

11, 11 suitably secured in bearings (not shown) so that the rol-1ers normally contact each other. They tightly grip the paper 10 fed therebetween and in the absence of any paper form a sealing contact.

A housing 12, as more clearly viewed in FIG. 2, has top and

bottom walls

13, 14,

end walls

15, 15', 16, 16 and inner walls, 20 and 20. The interior of the housing thus formed has a pair of box like closed

chambers

19, 19. The entrance to the area between the

chambers

19, 19 is sealed by the

rollers

11, 11 and by

wipers

21, 21 which engage the rollers at a point remote from their mutual contact, so as to seal this area against the outside atmosphere. The inner walls 20, 20' are perforated with a plurality of sized apertures as seen at 22, 22 to distribute the developing medium along the path of travel of the paper. The exit from the housing is formed by

rollers

18, 18 which together with

wipers

28, 28 seal the area between the

chambers

19, 19 in the same fashion as

wipers

21, 21 and the

rollers

11, 11.

Located within the

chambers

19, 19 are perforated

tubes

24, 24 which are coupled to a compressor 38 and supply developing medium from the compressor to the

chambers

19, 19 as will be more fully described. A portion of

chambers

19, 19 close to the

exit rollers

18, 18 is partitioned ott as seen at 25 and 25', respectively, to form exhaust duct connections which are coupled to the cornpressor for recirculating the developing medium.v The

boxlike chambers

19, 19 are wider than the paper 10 for which ythe apparatus is designed, so that developing medium introduced to the upper and lower box-

like chambers

19 and 19 can pass aound the edges of the paper 10l and between

edges

57 and 57 of end walls 20 and 20', respectively, and a housing frame 56 (shown in FIG. 3) to the

outlet ducts

25, 25.

If desired, heaters in the form of electrical heating elements may also be used in the 1box-

like chambers

19, 19. Four such heaters are shown in FIG. 1 at 26a-26d.

The entire system is best seen in FIG. 1. Anhydrous ammonia is passed through an input tube 30 into a duct 53 which has an opening 53' leading to a `gas generator or mixing chamber 31. Generator 31 is partly filled with water from a supply tube 32 entering at the bottom from a liquid level vessel 33; Iwhereby the liquid level in generator 31 and in vessel 33 are always at the same level. The level of the vessel 33 is maintained at a preselected height with the aid of a pump 34 pumping -water through a pipe 54, a valve 35 and a pipe 55 which leads into the top of the level vessel 33. Excess uid in the level vessel 33 is conducted to a sump 43 via a pipe 47, a valve 36 and a pipe 51, thereby maintaining the preselected level in vessel 33. The sump 43 supplies water for the pump 34 through a supply pipe 56. When aqueous ammonia is selected by a user, it is introduced into duct S3 through a pipe 40 and the excess fluid from generator 31 is conducted through

pipes

47 and 48 and through valve 44 and pipe 49 to a drain vessel 45. A pipe 41 in level vessel 33 and a pipe 46 in drain vessel 45 vent their respective vessels to atmospheric pressure.

In order to bring the ammonia and the Water to the proper temperature, mixing chamber 31 is provided with heater coils 37 which, like the heaters 26a-26d can be connected to a source of electrical power, not shown.

As previously mentioned, generator 31 is connected at 53' to the duct 53 which lhas a pair of outlet tubes, one connecting with supply tube 24 and the other with supply tube 24. The inlet to Ithe duct 53 is from a blower 38 which exhausts developing medium from

chamber outlet ducts

25, 25 to the blower inlet duct 40 as schematically indicated by arrows 39 and 39'. The connection of duct 25 to the duct 40 of blower 38 has been shown in phantom in FIG. 1.

The choice of whether to use anhydrous ammonia or aqueous ammonia is up to the user. When anhydrous ammonia is used the

valves

35 and 36 are opened and the pump 34 is operated to maintain the preselected Water level in vessel 33 which thereby maintains the same level in generator 31 as previously described. Passing anhydrous ammonia from pipe 30 over the water in generator 31, while supplying heat through heater coils 37 will cause a water-vapor ammonia mixture to exit through opening 53 and be supplied under positive pressure by blower 38 to ducts 24,124. The water vapor ammonia mixture will escape through

holes

22, 22 to float a sheet of paper 10 introduced between the

rollers

11, 11 in its passage through the machine. The ammonia-water vapor mixture can be retained at the proper temperature by means of the aforementioned heaters 26a-26d. The vapor mixture is again recirculated by the blower 38, and brought to the proper temperature and humidity content by means of heater 37 and the continuous supply of anhydrous ammonia. If the water level in generator 31 drops, for example, due to absorption of water by the paper, pump 34 will continue to supply additional Water to vessel 33 which provides Water via pipe 32 to restore the level in generator 31.

If the user chooses to use aqueous ammonia, the

valves

35 and 36 are closed and valve 44 is opened. In this case, the supply of water may be greater than that absorbed by the paper or used in the developing process. Therefore, in order to maintain the level within generator 31 constant and at the proper height, pump 34 is not used and excess fluid from level vessel 33 is drained through

pipes

47 and 48 through valve 44 and pipe 49 to the drain vessel 45.

An alternate way of supplying ammonia fumes, that is, a mixture of water vapor and ammonia to the developing surface, is to utilize only a single tube 24 or 24', with transfer slots at the lateral edges of the

perforated sheets

20, 20 and thereby to deliver fumes to both

chambers

19 and 19. The remainder of the travel of the vaporammonia mixture will be similar to that previously described-air is forced by blower 38 to pass through the generator 31 Where water vapor caused by heating the water, by means of heater 37, is conditioned with ammonia, to either supply in anhydrous form through tube 4 30, or in aqueous form through tube 40. Ammoniated and heated vapor under pressure is then made to enter the developer through either one of

tubes

24 or 24.

It should be understood that the length between the entrance and exit of the area between the chambers is smaller than the length of the sensitized paper to be developed. If, however, it is desirous to use paper with a length shorter than the distance between the entrance and exit, a pair of rollers may be inserted in this area to guide and support the shorter length of paper.

The foregoing disclosure relates to only a preferred embodiment of the invention, and that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purposes of the disclosure, which do not constitute departures from the spirit and scope of the invention.

The invention claimed is:

1. In developing apparatus having a developing chamber, in which a sheet of paper is introduced into said developing chamber, a mixing chamber having a pair of inlet means, one adapted for supply of anhydrous ammonia and the other for supply of aqueous ammonia; a heater in said mixing chamber; vessel means containing a liquid and connected to said mixing chamber for establishing a predetermining liquid level in said mixing chamber; a blower, in communication with said mixing chamber and delivering a water vapor-ammonia mixture therefrom; and means supplying said mixture of water vapor and ammonia under pressure into said developing chamber to float the paper thereon.

2. Apparatus as recited in claim 1 wherein a pump in communication with said vessel means provides water to said vessel supply means determined in proportion to the use of the water vapor-ammonia mixture and the supply of anhydrous ammonia.

3. An improved developing apparatus including a gaseous developing medium introduced under pressure to develop and support an exposed sheet of sensitized paper, the improvement comprising a mixing chamber for ammonia and water in communication with a fluid inlet means disposed adjacent a paper entrance means for introducing said ammonia and water into a pair of spaced apart, vertically disposed chambers respectively; a first supply tube for leading anhydrous ammonia into said mixing chamber; a second supply tube for leading aqueous ammonia into said mixing chamber; a heater in said mixing chamber; a supply vessel for water; and means interconnecting said mixing chamber and said water supply vessel whereby the fluid level in said mixing chamber is maintained at the same level as said Water supply vessel.

4. Developing apparatus as recited in claim 3 including a pump wherein the improvement comprises disposing said pump in uid circuit relation with an interconnecting means interconnecting a mixing chamber and a water supply vessel to establish, selectively, the level of uid in said water supply vessel.

References Cited 'UNITED STATES PATENTS 3,048,383 8/1962 Champlin 34-156 X 3,071,866 1/1963 Mangus 34-155 X 3,147,687 9/ 1964 Halden 95-89 X 3,192,846 7/ 1965 Wright 95-94 3,308,555 3/1967 Kruger 34-155 3,330,189 7/1967 Vil 95-89 X NORTON ANSHER, Primary Examiner.

C. E. SMITH, Assistant Examiner.

U.S. Cl. X.R.