US2404821A - Collapsible contact printer - Google Patents

Description

July 30, 1946.

W. U. ZELLER COLLAPSIBLE CONTACT PRINTER Filed Jan. 26, 1945 2 Sheets'-Sheet 1 nucmfo'o Patented July 30, 1946 OFFICE COLLAPSIBLE CONTACT PRINTER Wilbur Ulric Zeller, United States Army, New York, N. Y.

Application January 26, 1945, Serial No. 574,669

(Granted under the act of March 3, 1883, as

amended April 30, 1928; 370 O. G. 757) 4 Claims.

1 The invention described herein may be manufactured and used by or for the Government for governmental purposes, without payment to me of any royalty thereon.

This invention relates to contact printers used in photography for making light transfer prints and more particularly to collapsible contact printers.

Numerous attempts have been made to provide a collapsible contact printer or copying apparatus which is adapted to be folded into a small compact form and easily transported. One such attempt was disclosed in Patent Number 1,651,954, issued December 6, 1927, to Arthur Heyer. The copying apparatus disclosed in this patent comprised a conventional copying frame supported by U-shaped straps of fiat iron having stays extending between the straps and secured thereto by cotter pins or the like, and a light-impermeable bag depending from said copying frame. The light source consists of a standard glow lamp supported by a separable fixture. The foregoing device, while an improvement in the art, was not entirely satisfactory since it was not unitary, rigid or stable and it was not adapted to be disassembled imply and easily. This device was furthermore incapable of projecting light of uniform intensity on all parts of the copying plate since no means were provided for maintaining the form of the light bag or for positioning the source of light at the same predetermined point each time the apparatus is used.

This invention is an improvement over the invention disclosed in the above patent and the principal object of this invention is to provide a collapsible contact printer which may be simply and easily folded to occupy a small amount of space.

Another object of this invention is to provide a collapsible contact printer which is rigid and stable in both its operating and collapsed positions.

Another object of this invention is to provide a collapsible contact printer in which the various parts are in interlocking engagement in either the operating or collapsed position to prevent relative movement between the parts.

Still another object of this invention is to provide a collapsible contact printer which is a self-contained, wholly unitary structure.

A further object of this invention is to provide a collapsible contact printer having a plurality of light sources and a light reflecting means each adapted for positioning in a predetermined relationship with respect to the copying plate whereby light of uniform intensity is projected to all parts of the copying plate.

A still further object of this invention is to provide a collapsible contact printer having a light panel assembly provided with flange portions at the ends thereof adapted to engage either a pair of leg braces or the lower edges of the end walls of the copying frame.

Other objects will be apparent from the following description of the invention and the accompanying drawings in which:

Figure 1 is a perspective View of the collapsible contact printer in its operative position;

Figure 2 is top plan view of the contact printer with portions removed;

Figure 3 is a side view in cross-section of the contact printer taken along line 33 of Fig. 2;

Figure 4 is a bottom perspective view of the contact printer in its collapsed position;

Figure 5 is a top plan view of a combined carrying case and developing trays for se with the contact printer; and

Figure 6 is a perspective view of the carrying case with the contact printer supported therein.

Referring to the drawings, the contact printer comprises a frame I 0 having side walls H and end walls l2 formed of sheet metal. The upper edges of the side and end walls are folded inwardly upon themselves to provide a flange memher [3. Angle members 14 are mounted on the inner faces of the side and end walls I! and I2 and extend entirely around the inner upper end of the frame l0, being spaced a slight distance below the upper edge thereof to provide a support for a transparent glass or transparent synthetic resinous copy plate 15. The over-all dimensions of the frame [0 oi the printer are such that the copy plate 15 is large enough to accommodate legal-size documents. The printer is provided with a cover l6 consisting of a pair of plates I'I-Il connected by a hinge [9. The outer ends of the plates l'l-l1 are turned down to form the flanges Ila-Ila, one of which is pivotally secured to an end wall I?! of the frame H! by a hinge 25. The plates H-l1 have felt pads 2l-2l attached to their lower faces which are adapted to engage the surface of the copy plate l5 when the cover I6 is closed or to press sensitized paper and documents into intimate contact with the entire surface of the copy plate I5 to obtain clear photographic prints.

The printer is provided with a bellows 22 which is attached to the inner lower face of the frame I!) by a pair of side plates 23 and a pair of end plates 24. The bellows 22 is formed of light weight leather or a durable fabric and is coated with aluminum pigmented paint or lined with a white material to provide a light reflecting surface. The upper ends of the bellow 22 are clamped between the end and side walls of the frame In and the end and side plates, and the respective members are then secured by screws 25 which pass through threaded apertures provided in the members. The printer is also provided with four legs 25-46 and 2fia-26a formed of sheet metal angle strips. The legs have apertured extensions 21 arranged to engage the side walls I! of the frame l and thus form pairs of right hand legs 2626 and left hand legs flirt-26a. The pins 28 pass through the apertures in the extensions 2'! and corresponding apertures in the side walls of the frame It. The legs 26 may thus be pivoted about the pin 28 and folded along the lower edge of the side walls II. The pairs of legs at adjacent ends are provided with reinforcing metal strips or braces 29 and 3B which are welded to a side of each leg angle. The reinforcing strip 30 has an offset portion 3| formed therein and both of the metal strips 29 and 30 have elongated openings 32 formed therein.

The lowermost end of the bellows 22 is connected to a light panel assembly indicated generally as 33. The light panel assembly 33 comprises a light panel 34, a panel support 35 and a bottom plate 35. The light panel 3 is a rigid rectangular plate formed of Bakelite or other electrical insulating material. The panel 34 is provided with a plurality of apertures in which are mounted the porcelain or Bakelite lamp Sockets 3'! which are adapted to receive the flashlight bulbs 38. Near the center of the panel 36, additional apertures are provided in which a clamp 39 and the contact fingers iidfi are mounted. The jaws of the clamp 39 are adapted to receive and engage the insulated sides of a standard flashlight dry cell ll and the contact fingers 66 are adapted to engage the positive and negative terminals of the dry cell Q l. The contact fingers M are connected with the lamp sockets 3 through a suitable circuit 52 which includes a standard single position ofi and on rotary hand switch that is mounted on the panel support 35. dditional apertures are provided in the light panel 3% in which the small 110-volt clamptype lamp sockets Ml provided with contact fingers Ma are mounted. The sockets 5 are adapted to receive the bulbs i5 and are connected by a suitable circuit it with a standard male plug 4? which may be connected in turn with a 110-115 volt source of current.

The panel support 35 is formed of a rectangular piece of sheet metal having its sides and ends folded upwardly to provide the flange members Ai3fl8 and 4S- i9 respectively. The panel support is also provided with a rectangular opening 35a which is small enough to form a ledge adjacent the flanges iti 53 and fiQl9 for supporting the light panel 3 The angle members 55] are welded to the panel support 35 and are spaced slightly apart from the flange members 69 to provide a channel which is adapted to engage the sides of the metal strips 29 and 39, The width of the panel support 35 and the angles 56 is slightly less than the length of the elongated openings 32 in order that the vertical edges adjacent the openings 32 extend downwardly past the edges of the panel support 35 when the latter engages the strips 29 and 38. The arrangement described permits positive engagement between the panel support 35 and the strips 29 and 3t! and prevents horizontal movement of the panel support 35 when the members are so engaged. The angles 56-56 are also adapted to engage the outer faces of the lower edges of the end walls I 2 of the frame it and thus prevent movement between the light panel assembly 33 and the frame I0 when the printer is collapsed. A pair of angle members 5l-5i are mounted on the panel support 35 and spaced apart a distance slightly larger than the length of the light panel 3%. The angle member 51 adjacent the rotary switch 33 has a slot 52 formed therein through which the wires forming the'circuits i2 and 46 may extend to the switch it and the plug 4'1. The wires forming the circuits t2 and 45 also pass through a recess formed in the panel support 35 by the stamped portion 35b. The bottom plate 35 which is formed of Bakelite or other rigid electrical insulating material is attached to the lower face of the panel support 35, A plurality of registered apertures are formed in the panel fi l and the plate 3'6 through which the bolts 53 pass. The plate 36 is also provided with a cut-out portion 38a which is adapted to fit around the stamped portion 35b. The lower ends of the bellows 22 extend downwardly along the vertical faces of the angles 51, and the flanges i8 i8 extend thence horizontally between the edges of light panel 34 and the ledge portions of the panel support 35 adjacent the opening 35a where it is clamped therebetween by tightening the bolts 53.

It is apparent from the foregoing description that the operative position of the contact printer is that in which the legs itsand 26a-2'5a are arranged vertically, the bellows 22 extended and the leg braces 29 and 3&1 engaged in the channels formed by the flanges E-9 -ii and the angles 5dt. The flashlight bulbs 33 and the electric lamps are located at a point from which either source of light, depending upon which the operator desires to employ, may project light, equally, in the proper amount on all parts of the copying plate IS. The fixed and predetermined relationship of the bellows 22 and the light panel 34 with respect to the copying plate It supported by the frame iii insures an even distribution of light on the document and the sensitized paper supported by the plate 95. The interlocking engagement of the various parts of the contact printer provides a strong, rigid and stable construction. In operation, the cover it is raised and the document to be copied and sensitized paper of a suitable grade are placed on the surface of the copying plate 15. The cover [6 may then be closed and the felt pads 2i--2l pressed against the document and sensitized paper, thus forcing the latter into intimate contact with each other and the copy plating 15 in the customary manner. The rotary switch 43 may then be turned on, allowing current to flow from the dry cell iii through the circuit 32 thus lighting the flashlight bulbs 33. The light from the bulbs 38 is projected on the copying plate 5 for predetermined length of time according to the judgment of the operator, following which the rotary switch 13 is turned off. If a standard 110-115 volt alternating current source is available, the male plug li may be connected thereto and by means of a suitable switch current may be supplied through the circuit to the lamps 45. Following its exposure, the sensitized paper may be removed from the printer and developed in the usual manner. While it has not been disclosed, a conventional form of timing switch such as that disclosed in Patent Number 2,336,663, issued December l i, 1943, to Carl F. Wolters, et al., may be mounted on the panel support 35. Such a timing switch may be included in either of the circuits 42 and .6 or in both and may be connected in series with the rotary switch 43 or the male plug 47. Thus with the switch 43 r the male plug 47, the circuits carrying current to bulbs 38 or the lamps 45 may be partially completed and subsequently completed by the timing switch. The conventional form of timing switch may be set to control the circuits so that they are closed for a definite period of time automatically determined by the timing mechanism within the switch structure.

The printer may be collapsed by disengaging the leg braces 29 and 30 from the channels formed by the flanges 49-49 and the angles 50-50. The bellows 22 is then folded by forcing the panel support 35 toward the frame 10. The angles 50-50 are engaged with the outer faces of the lower edges of the end walls l2 of the frame ID. The pair of legs 26-26 between which the leg brace 29 extends are pivoted downwardly toward the frame ID until one side of each of the angles forming the legs 26-26 extend downwardly along the lower outer edges of the side walls [I of the frame 10. The brace 29 engages the light panel assembly 33 and forces it downwardly toward the frame 10. The pair of legs 26a-26a between which the brace 30 having the off-set portion 3| extends are similarly pivoted downwardly until one side of each of the angle strips forming these legs engages the corresponding angles of the legs 26-26 which have already been folded. The ofi-set portion 3| permits the legs 26a-26a to fit snugly on the legs 26-26. The printer is thus completely collapsed into a small compact form as shown in Figure 4. The various parts of the printer are interlocked and all relative movement therebetween is eliminated thus avoiding breakage or other damage.

The printer described may be easily transported since it occupies a very small amount of space. A suitable carrying case is shown in Figures 5 and 6 consisting of upper and lower receptacles 54 and 55 formed of sheet metal. The receptacles 54 and 55 may be connected by detachable hinges 56-56. The carrying case is also provided with the conventional latches 51 and a pair of handles 58-58. One feature of the carrying case described is that the upper and lower receptacles 54 and 55 may be separated by moving these members laterally to separate the hinges 56 and the receptacles thus adapted for use individually as developing trays. The carrying case is made large enough to hold not only the collapsed printer but also a supply of sensitized paper and developing materials in a dry form. The contact printer when collapsed fits into the carrying case as shown in Figure 6 and may be easily transported or stored in a small place in its collapsed position.

Having thus described my invention, what I claim as new and wish to secure by Letters Patent is:

1. A collapsible contact printer, comprising a frame, a copying plate mounted adjacent the upper end of said frame, leg members pivotally connected to said frame adjacent the ends thereof, said leg members being adapted to be folded upon said frame, leg braces secured to adjacent pairs of leg members at the ends of said frame, a flexible bellows, the upper edges of said bellows being attached to the lower end of said frame, a light panel, illuminating means mounted on said light panel, and a light panel support having a pair of spaced flange members adjacent each end thereof and adapted to engage said leg braces, said light panel and said light panel support being attached to the lower edges of and supported by said bellows.

2. A collapsible contact printer as set forth in claim 1 characterized in that the lower edge of each of said leg braces is provided with an elongated opening adapted to receive an end of said light panel support having spaced flange members mounted thereon, said spaced flange members being adapted frictionally to engage a leg brace and the vertical edges in each of said leg braces adjacent said openings being adapted to extend below the edges of said light panel support.

3. A collapsible contact printer, comprising a frame providing side and end walls, a copying plate mounted adjacent the upper end of said frame, leg members pivotally connected to the side walls of said frame adjacent the ends thereof, said leg members being adapted to be folded upon said frame, leg braces secured to adjacent pairs of leg members at the ends of said frame, a flexible bellows, the upper edges of said bellows being attached to the lower end of said frame, a light panel, illuminating means mounted on said light panel, and a light panel support having a pair of spaced flange members adjacent each end thereof adapted selectively to engage either said leg braces when the printer is in an operative position or the outer face of the lower edges of said end walls when the printer is in a collapsed position, said light panel and said light panel support being attached to the lower edges of and supported by said bellows.

4. A collapsible contact printer as set forth in claim 3 characterized in that one of said leg braces is provided with an off -set portion adapted to extend across the lower face of said light panel support and downwardly past the edges thereof when said printer is in a collapsed position.

WILBUR ULRIC ZELLER.

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