US2578048A - Combined printer and drier for planographic printing plates - Google Patents

Description

INV QR Dec. 11, 1951 R. A. DALTON COMBINED PRINTER AND DRIER FOR PLANOGRAPHIC PRINTING PLATES Filed June 4, 1949 5 Sheets-Sheet l Dec. 11, 1951 Filed June 4, 1949 R. A. DALTON COMBINED PRINTER AND DRIER FOR PLANOGRAPHIC PRINTING PLATES 5 Sheets-Sheet 2 INVENTOR 0o 4 8 7 5 2 mw T mm M P NDn u ODI N T L m T mm R H R M ma N 0 mm M L OP. C

Dec 11, 1951 Filed June 4-, 1949 3 Sheets-Sheet 3 {III/111111117171 Patented Dec. 11, 1951 COMBINED PRINTER AND DRIER FOR PLANO GRAPHIC PRINTING PLATES Robert A. Dalton, Fairfield, Conn., assignor to Remington Rand Inc., New York, N. Y., a corporation of Delaware Application June 4, 1949, Serial No. 97,194

3 Claims.

This invention is concerned with the provision of a plate drier and printer for flexible litho graphic plates in which means are provided for the storing and drying of plates which have been coated with sensitizing solution and the exposure of portions of the dried coated plates to light in order to print upon them the desired text or design. It is particularly designed for use with flexible paper, fiber, or plastic lithographic plates such as are widely used in offset printing.

The device of the invention comprises a number of novel features including supports and racks for holding the coated plates in properly spaced position during drying, means for circulating air which may be heated over said plates, means for conveniently exposing the dried, sensitized plates to light in contact with a photographic negative or written or printed material which it is desired to reproduce, and an automatically controlled light source. These features are combined to obtain operation of the device in a convenient and eiiicient manner.

The present invention makes possible the small scale production of lithographic plates for offset printing so inexpensively and conveniently that such plates may be employed in many cases where their use was formerly impractical because of the necessity for expensive and complicated equipment which could not be installed or operated by many persons who desire to use them.

In the drawings:

Fig. 1 is a perspective showing the assembled plate printer and drier constructed according to the invention.

Fig. 2 is a rear elevation of the cabinet.

Fig. 3 is a horizontal cross-section taken on line 3-3 of Fig. 2 showing the internal arrangement of the cabinet.

Fig. 4 is a vertical cross-section taken on line 44 of Fig. 3, illustrating the use of the drying rack.

Fig. 5 is a perspective showing a. block used in forming the rack supports.

Figs. 6 and 7 are perspectives showing the manner in which the supports are installed.

Fig. 8 is a wiring diagram illustrating the electrical hook-up between the different parts.

The drier and printer of the present invention comprises a cabinet l9 having a bottom ll, top [2, front I3, and back It. Said cabinet has a closed end [5, the other end being closed by a door It adapted to be swung open and closed on hinges [1. Door [6 is provided with a handle 18 and a spring catch it for yieldingly maintaining the door in closed position.

Mounted on top l2 of cabinet i0 is a printing frame 20, pivotally attached by hinges 2| to the back of cabinet I E. A clear glass plate 22 is mounted in frame 20. A resilient supporting pad 23 is mounted on top 12 within frame 20 under glass plate 22 for supporting a lithographic plate in position to be exposed. This pad may conveniently be formed of sponge rubber. A pair of latches 2d are mounted on front 13 of cabinet II] to cooperate with lugs 25 on frame 2d to hold the latter in closed position.

The construction of the rack supports and spacing means in the interior of cabinet It] will be understood by reference to Figures 5, 6 and '7. Supports 30 are fashioned from a block of material 3!, which may be of wood or other suitable material, by forming a series of parallel slots 32 in one face of block 3!, spaced apart the distance desired, extending only partially through said block and leaving an unslotted portion 33 integral with supports so at the other face of the block. The slotted faces of blocks 31 are then coated with glue or other suitable adhesive and placed in the proper corresponding positions against the front and back of cabinet ID, as shown in Figure 6 in connection with back I4.

When the adhesive has set so that blocks 3| are firmly affixed to the front and back of cabinet NJ, the unslotted portions 33 of blocks 3| are planed off to expose slots 32 and leave supports 38 attached to the front and back of cabinet I0 and separated by spaces or slideways formed by slots 32. If desired, additional means such as screws (not shown) may be used to fasten supports 38 in position.

As a result of this method of installing supports and spacers 39, their proper positioning is assured without the necessity of making accurate measurements as each supporting strip is placed in position, and much time and expense is consequently saved. After unslotted portion 33 has been removed, strip members 34 are attached at the inner ends of supports 30 on each side of cabinet I!) to serve as stops for racks or shelves and to insure their proper positioning in slideways 32.

Racks or shelves 4!? are ioraminous and are preferably formed of wire rods soldered or welded together, but the use of expanded metal or stiff wire cloth as a substitute is possible. In the embodiment shown in the drawings there has been provided space for six racks or shelves, but it will be understood that this number may be increased or decreased as desired, within the limitations imposed by the size of cabinet in.

The top and bottom shelves or racks 40 are preferably joined at their rear ends as by a rod or wire 4| which is conveniently attached to the racks by loops 42 leaving projecting ends 43. Wire or rod 41 thus serves as a stop for lithographic plates 44 which are placed on shelves at.

A timer 55 and switches and 52 are mounted on front l3 of cabinet [0. Timer 55 and switch 5i control lamp 54, as best shown in Figure 8. Switch 52 controls heater and blower 53 which is mounted inside cabinet in and is provided with an air inlet 54 and an air outlet 55.

An adjustable clamping support having clamping jaws 6| controlled by means, such as a handwheel 62 is mounted on back l4 of cabinet ill. A tubular lamp support 63 is held by jaws BI and extends vertically above cabinet Hi and is bent at its upper end to support a depending lamp 64 over printing frame 20. An electrical cord 65 is carried in tube 53 to supply current to lamp 64. Cord 65 may conveniently be terminated in a plug 66 adapted to be received in socket 61 mounted in back 14 of cabinet 15. Cabinet ID is provided with a cord terminating in plug H for attachment to any suitable current supply source.

Lamp 54 may be of any desired type which will furnish sufficient actinic light to properly expose the sensitized lithographic plates. The adjustability of lamp support E3 permits the lamp to be raised or lowered over exposing frame to provide desired lighting conditions. The provision of the plug 66 and socket 51 on the back of cabinet It! permits the convenient removal of thelamp support and lamp without the necessity of disassembling permanent electrical connections. The lamp support may be constructed to mount two or more lamp bulbs of any of the types now used for photographic printing purposes.

The process of drying lithographic plates and exposing or printing them by the use of the apparatus of the present invention is a simple and convenient one. Plates 44 which have been coated with a sensitizing solution are placed in cabinet in on shelves or racks 4! The len th of the shelves is preferably such that when the inner end of the plate 44 is in contact with the stop 4|, the free end of the plate extends beyond the outer end of the shelf for convenience in grasping it. The door I5 is then closed and switch 52 is turned to On position, thus closing the circuit to heater and blower 53 which circulates heated air in the heater chamber and over the plates resting on racks 40. The door may be left ajar during the drying of the plates, if desired, even though it is found that sufficient air can be circulated around the door in closed position, since it is not tightly fitted. After a coated plate has been dried for at least a minute it is ready to be exposed. It is withdrawn from the cabinet, frame 28 is raised, the sensitized plate is placed on resilient pad 23 and covered by the negative, drawing, or other copy which it is desired to reproduce. The plate and copy are held in close, firm contact with pad 23 by frame '20 which is lowered and clamped. Switch 5E, connected in series with timer is then moved to on position and timer 50 is set to provide the predetermined required period for exposure to light from lamp 64.

While one plate is being exposed, the operator may be employed in applying sensitizing solution to another plate which will then be dried in cabinet Ill, or, if a supply of sensitized plates has been placed upon shelves 40, the operator may be engaged in developing a previously exposed plate or in other activities. When the time for exposure has elapsed the lamp is automatically extinguished. Frame 20 is raised and the exposed plate together with the copy or negative may be removed and replaced by a fresh plate and a new negative or new copy.

It will thus be seen that the components of the drier and printer of the present invention are so conveniently arranged that only a single operator is required to prepare plates with sen sitizing solution and to expose and develop the sensitized plates. The invention provides a compact, sturdily constructed single unit with the top wall of the cabinet forming a copy table with frame 20, The device is inexpensive to manufacture and operate by combining the printing frame with the cabinet structure, also mounting the printing lamp structure and controls.

The copy positioned on the copy table is in full view of the operator when the frame is latched on the copy table in printing position and the accuracy of its position can be easily and visually checked. It will also be understood that the heater may be omitted from the blower, if desired, and the blower used to circulate air of room temperature which, under some conditions, may be considered adequate for drying the plates.

The invention claimed is;

.1. portable printer comprising a cop ta le formed y a top wa l, a front and a has depe ding in spaced relation from the front and rear edges of said copy table, end closures below said top and at the end. of said top, front and back. a printing frame mounted on top of said 90?? table, hinge means connecting said printing frame to said back below the upper surface of said copy table, a clamping support mounted on an interlmediate portion of said back below said copy table projecting rearwardl'y from the back, a tubular lamp support mounted in said clamping support in the rear of said back at the lower end, extend ing vertically above said clamping support and having a bend portion at the upper end exien'd ing forwardly over said copy table with a depending from the free end thereof, lamp" support positioning said lamp at a distance above said copy table sufficient to have said printing frame freely movable without obstruction from engagement with said cosy to engage and rest against said lamp suppo t p n po ition.

- table for engaging and retaining fie d i time said we and latch means on said front bale frame in sheet holding position in n e with said copy table,- Said hinge means, lamp s port, clamping supporting and latch means lee ing located below said copy table to leave free and unobstructed access to said copy table from the ends and front of said printer for conven nt manipulation of sheet material being placed and removed from said copy table, and said as sembled structure forming a small portable unit for'support on a desk, table or the like in normal.

use.

2. A portable printer of the character claimed in claim 1, wherein a bottom connects the lower edges of the front, back and end closures in co-- operation to form a cabinet having access to the interior provided through movement of pne of said end closures whereby printing plates be processed on said copyholder and in aid ca inet, and said cabinet with said copy table frame and. lamp support forms a small p rta le suit 5 for manual transportation and support on a desk, table or the like.

3. A portable printer of the character claimed in claim 1, wherein a bottom connects the lower edges of the front, back and end closures in cooperation to form a cabinet having access to the interior provided through an end thereof, and shelves mounted in horizontal relation in said cabinet whereby sheet material printing plates may be successively moved to said copy table from said shelves in said cabinet during processing thereof, and the assembly structure forms a small unit readily transported from place to place and requires a desk, table or the like for support in normal use thereof.

ROBERT A. DALTON.

REFERENCES CITED The following references are of record in the file of this patent:

6 UNITED STATES PATENTS Number Numb er Name Date Lowell Apr. 11, 1882 Spaulding Feb. 21, 1928 Taylor Jan. 7, 1930 Rogers Nov. 30, 1937 Jernsen Sept. 15, 1942 Wolters et a1. Dec. 14, 1943 Corbin Aug. 14, 1945 Lank Aug. 27, 1946 Campbell Dec. 10, 1946 Kilbury Dec. 10, 1946 Willcox Jan. 21, 1947 Mo Gee May 10, 1949 Zachmann et al. June 20, 1950 FOREIGN PATENTS Country Date Great Britain Feb. 12, 1940

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