US2024678A - Apparatus for making blueprints - Google Patents

Description

Da. 17, 1935. H, L BRUNk 2,024,678

APPARATUS FOR MAKING BLUEPRINTS Filed April 14, 1933 3 Sheets-Sheet l' ATTORNEY.

Dec. 17, 1935. H- BRUNK APPARATUS FOR MAKING BLUEPRINTS Filed April 14, 1933 3 Sheets--Sheel 2 NVENTOR.

ATTORNEY n@ 1 0 j m O j 1 S y M w mi 3 H. J. BRUNK APPARATUS FOR MAKINGV BLUEPRINTS Filed April 14, 1933 3 Sheets-Sheet 3 m1 mm j,

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ATTORN EY.

Patented Dec. 17, 1935 UNITED STATES APPARATUS FOR BIAKING BLUEPRINTS Harold J. Brunk,.Chicago, Ill., assignor to The C. F. Pease Company, a corporation of Dela- Wavre Application April 14, 1933, Serial No. 666,192

5 Claims.

My invention relates to improvements in apparatus for making blue prints and other prints in which sensitized sheets of paper are exposed to light and then washed and dried.

So-called continuous blue printing machines are now used extensively in which a wide band of blue print paper is fed from a supply roll and passes slowly but continuously over a curved glass plate and over a succession of rollers, during whichmovement it is exposed to arc lamps and thereafter washed and dried. These machines are motor driven, and as they involve considerable mechanism, are relatively high in price. Also, motor driven driers have been. used for drying blue prints exposed by the' use of other types of blue print equipment and washed in various ways. These motor driven driers are fairly large and also comparatively high in price.

The object of the present invention is to provide a small machine having many of the advantages of these larger and higher priced machines, but requiring no motor, being operated by hand.

Another object is to provide a machine of this character having a rotatable cylinder to which a belt or band is attached and from which it extends in a tightly stretched, downwardly in.- clined span, the tension being maintained by a spring, whereby prints in the making may be laid on said inclined span and drawn around said cylinder in smooth, firm engagement therewith and treated by light or heat from an electrical source within said cylinder.

@ther objects and advantages will be apparent from the following description taken in conjunction with the drawings in which the invention is illustrated in several` different forms.

Fig. l is a top view of one embodiment of the invention;

Fig. 2' is a front view thereof;

Fig. 3 is a side elevation;

Fig. 4 is a side elevation of certain details;

Fig. 5 is a diagrammatic showing of a modined form of the invention;

Fig. 6 is a diagrammatic' showing of a further modiiication; A

Fig. 7 is a front elevation of another embodiment of the invention; and

Fig. 8 is a side eleva-tion thereof.

Referring to Figs. 1, 2 and 3, which illustrate equipment intended to dry blue prints, there is shown a suitable base I having feet I I to elevate it slightly above the bench or table. The base forms part of a housing or cabinet having side walls I2 and an upper wall I3, which, as shown in Fig. 3, is inclined with its lower end bent down vertically and its upper forward end bent horizontally, these various walls forming a sheet metal housing which is open at the front.

A cylindrical drum I4 is mounted in the hous- 5 ing. Itis made of heat conducting material such, for example, as copper or brass, and is supported at'its right hand end, as viewed in Fig. 2 by a short shaft I and at its left hand end by a short tube I6, each of which passes through a suitable 10 bushing il in the side wall, which bushings serve as bearings, permitting rotation of said cylinder.

A belt or band i8, made preferably of fabric, has one end fastened to the' cylinder at I9. As shown in Fig. 3, this band is arranged to wrap around the cylinder to a certain extent when the latter is rotated, said band passing forwardly and around a roller 20, with its rear end secured to suitable means for drawing it rearwardly, i. e. in a. direction to unwind it from the cylinder I4. Any suitable means may be employed for this purpose. Theone shown in Fig. 3 consists of a metal band ZI wound on a spool (not shown) contained in a box 22, the spool having a spiral spring therein tending to wind the metal band about it. in other words, the spring tends to draw the metal band into the box, thus drawing the lower rear edge of the belt rearwardly. Spring actuated reels of this character with a metal band or tape are known commercially as Pullman springs. When the cylinder I4 is rotated by hand or otherwise in the proper direction, as hereinafterl described, the band IS is wound partially around the same, thereby drawing the metal band 2l out of its container 22. The span 35 of the belt 23 between the roller 20 and the cylinder or drum i4 is inclined upwardly from front to rear, whereby a wet blue print placed thereon prior to the rotation of said cylinder will be drawn around the cylinder and pressed tightly against the same in smooth contact therewith, without wrinkling, and the water in the blue print will be wrung therefrom at the point 24 as the print is being squeezed between the band and the cylinder, said water flowing down the inclined span 23 45 and running off the lower end thereof.

As hereinafter pointed out more fully, the mechanism thus far described is intended as a drier,

with a heating element within the drum, although by substituting a glass cylinder for the copper cylinder and locating a suitable source of light within said drum instead of said heating element, the mechanism may be employed as a printer to exposed blue prints, the print and the 'overlying tracing being held smoothly against `the drum by the belt.

The means for manually rotating the drum, irrespective of whether it is used as a printer or a drier, will now be described. The short sh-aft I5 has a handle 25 rotatably mounted thereon as shown in Fig. 3 and carries a pivoted pawl 26 which engages the` teeth of a ratchet wheel 21, which latter is fixed to said shaft. Pins or stops 28-'29'project from the side wall of said housing ag-ainst which said handle may rest in either of its two extreme positions. The operator oscillates the handle back and forth and the shaft and the drum to which it is secured will rotate in counter clockwise direction, as viewed in Fig. 3, to wrap the belt around said drum against the action of the Pullman spring or other yielding means resisting such action. A small hand wheel 30 is also fixed to said shaft |5 whereby the latter may be rotated thereby, preferably for the purpose of turning the drumin the opposite direction, i. e. in a clockwise direction as viewed in Fig. 3, which rotatation is normally resisted by braking means which will now be described.

On the hollow shaft I5 at the'left hand end of the drum as viewed in Fig. 2, is fixed a pulley 3| Vover which passes a tension member or cord, such, for example, as a leather belt 32 (see Fig. 4) one end of said belt being fastened to a pin 33 mounted in the side wall of the housing, the other end beingsecured to a spring 34 to hold the belt in frictional engagement with the pulley and thereby resist rotation of the latter. A ratchet wheel 35 is also secured to said hollow sh-aft'and has a pawl 36 actuated by a pivoted handle 31 for holding the drum against rotation against the action of the Pullman spring, which tends to unwind said belt from said drum. That is to'say, the operator, when he rotates the drum by oscillating the handle 25, wraps the band around the drum against the action of the retractile spring -acting on the other end thereof and the pawl and ratchet mechanism 35--36 holds said drum against reverse rotation. The tension of the leather belt 32 is adjusted preferably to permit the drum to turn back slowly to its initial position rather than to hold it with sufficient friction to prevent rotation. Without this brake, the belt would unwind with such rapidity as to jar the machine at the endof the movement.

The hand wheel 30, by being made sufiiciently large, can be used to rotate the drum to wind the belt around it as well as to rotate it in the reverse direction against the action of the braking mechanism when the pawl and ratchet mechanism 35-36 are disengaged. However, the handle 25 aiords an increased leverage in rotating the drum against the tension of the Pullman spring, whereas much less effort is required to rotate said drum in the opposite direction. The heating element within the drum for drying the print may be either' electricity or gas, but in the present instance, as shown, it is a helical resistance element 38 wound about a cylindrical base 39 with its ends connected to suitable conductors 40--40 which pass out of the hollow shaft I6 to a suitable source of current. Since the drum rotates back and forth less than a complete turn, the twisting of the conductors udll-4|) gives rise to no difficulty and by passingthrough the hollow shaft directly to the heating element', the use of slip rings is avoided.

In Figs. 7 and 8 I have illustrated more in detail the mechanism employed where the equipment is used as a printer rather than a drier, although the diagrammatic showing in Figs. 5 and 6 is intended to yillustrate either a drier or printer in its main parts. In these two gures.. the band I8 is unwound from and rewound onto 5 a spring roller 4|. l The same reference characters have been used in Figs. 7 and 8 as in Figs.. l,

2 and 3, to indicate substantially the same parts. 'I'he cylinder, however, which is made of glass is in this case lindicated by 45 and is supported at 10 opposite ends by metal cylinder heads or caps 46 having central bosses or flanges, said heads being held in spaced relation by a cross bar 41.

The cylinder is rotatably mounted by having short lengths of pipe 48 screwed into the bosses 15 on the heads 46, such pipe lengths passing through the side walls and being journalled therein. The cylinder may be rotated by means of a pawl and ratchet mechanism similar to that shown in Fig. 3, although by way of showing an 20 alternative construction I have illustrated the clutch member 49 mounted on the right hand pipe vor hollow shaft 48, as viewed in Fig. 7, with a complementary clutch member 50 "loosely mounted'on said pipe and having a handle 5| 25 secured to it so that the operator may turn the drum to wrap the band |8 around it in the same manner as heretofore described. A collar 52 secured to the pipe 48 limits the lateral movement of the clutch member 50 and said collar may be 30 knurled to form a hand wheel similar to and for the same purpose as the hand wheel shown in Figs. 1 and 2.

The light for printing is preferably a mercury vapor tube 53 which passes completely through 35 the ydrum and the hollow shafts |8 with its projecting ends supported in suitable brackets or clamps 54-55 at the right and left hand ends respectively of'Fig. 7, which clamps hold said mercury tube out of contact with the hollow 40 bearings and other parts and with the terminals 56, 51 readily accessible. The insulated conductor 58 which is connected to the right hand terminal o-f the tube, passes through the casing to the smaller housing or extension 59 at the left 45 hand side of the main housing, in which smaller compartment the mercury vapor tube starting coil 60 is located. The left hand end of the tube is connected through suitable conductors 6|-62 to said starter coil through a suitable switch 63. 50

It is evident that a standard time switch could be used in connection with this mercury vapor tube to automatically shut ofi `the current after any predetermined length of exposure.

In operating the machine, the switch is in the 55 off position while rotating the glass cylinder;by hand to draw in the negative and the sensitized paper between said glass cylinder'and the band, after which the circuit may be closed and the prints exposedior the correct amount of time. 60 Fig. 8 shows the relative position of. the parts during exposure with the belt wrapped almost completely about the cylinder. When the print is finished, the operator moves the ratchet handle 31, shown at the left hand side of Fig. 7, to disengage the pawl and ratchet 35, 36, and turns the hand wheel 52 shown at the right hand side thereof, although the spring pulls the band back to initial position with only slight additional .assistance from said hand wheel. It is understood, 7o of course, that the spring also keeps the belt tight so as to insure holding the negative and sensitized paper smoothly against the cylinder during exposure.

Inthis printing device as in the case of the 75 drier previously described, a spring curtain roll such as illustrated in Figs. 5 and 8 may be used instead of the Pullman spring. This would be advantageous, particularly in the case of large cylinders, as for example those having a.` diameter of I4 inches, in which case a spring roll would result in a more compact structure.

In both the drier and the printer the cylindrical surface around which the band is rolled need not be acomplete cylinder but may be only a 'partial cylinder. Fig. 6 illustrates a half cylinder 6l which may be made of copper or other heat conducting material in'one case, or of glass or other transparent material in the other case.

Various other4 modifications in the structures may be made without departing from the scope of. the invention.

I claim:

1. Blue print and the like equipment comprising a rotatable memberhaving an arc`shaped outer surface, a shaft which turns therewith, a band having one end secured to said surface, spring means attached to the other end of said band tending -to withdraw the latter from said member, means for-rotating said member in a direction to wind said band thereon and draw in a sheet ofmaterial between said member and said band, friction ineans applied to said shaft to resist rotation of said shaft and member, andV additional means for rotating the latter in the reverse direction to release said sheet of material.

2. Blueprint and the like apparatus comprising a cylinder, shafts projecting in opposite directions'therefrom, journals therefor, a clutch associated with one of said shafts, a handle for` actuating said clutch to rotate said cylinder in one direction, a second handle for rotating said cylinder in the opposite direction, a band having a width nearly equal to the length of said cylinder and secured thereto at one endA and spring means secured to the other end whereby rotation of, said cylinder in one direction will roll said band partially around said cylinder against the action of said spring means and a brake resisting the action of said spring means, to permit said band to unwind slowly from said cylinder.

3. Blue print equipment and the like comprising a casing having a base and side walls but open at the front, a roller mounted horizontaliy near said base, a larger cylinder mounted above said roller to the rear thereof said cylinder being iournaled in said side walls, a band secured to said cylinder and extending from the bottom thereof forwardly around said roller and rearwardly, spring means arranged at the rear of said base for drawing said band rearwardly and thus rotating said drum, a handle outside of said 45 casing for rotating said drum in opposition to the action of said spring means, a brake at the other end of said drum resisting rotation of the latter and electrical means mounted in said cylinder near the axis of rotation thereof. 10 4. Blue print equipment and the like comprising a housing having bottom, side and top walls,

a cylinder having projecting shafts mounted in said side walls, one of said shafts being hollow, a4 clutch member mounted on one of said shafts 15 outside of. said housing, a handle for actuating said clutch for rotating said cylinder in one direction, a second handle associated therewith for rotating said cylinder, a pulley on the other of said shafts, a belt surrounding said pulley with 20 ,one`end fixed, a spring secured at the other end to hold said belt under tension and create .friction to resist rotation of said cylinder, a pawl an'd ratchet associated with said shaft, a roller below said cylinder near the front of said hous- '25 in g, a 4belt secured tol said cylinder passing downwardly around the rear of the same and forwardly to said roller, around the latter and rearwardly, spring means secured to the rear end of said belt tending tounwind said belt from said 30 cylinder, and an electrical device within said cylinder` rendered accessible through said hollow'shaft for connection with an external circuit.

5. A drier for blue prints and the like comprising an elongated member of insulating material, a resistance element mounted thereon to form a heating unit, a cylinder of heat conducting material surrounding said heating unit, a hollow journal for said cylinder, conductors passing 40 therethrough to said heating unit, a band having one-end secured to said cylinder and extending therefrom in a downwardly inclined span, a spring maintaining the tension of said span,

means for rotating said cylinder to wind said 45 band around it and wring water from a wet print positioned on said span to be drawn in between said bandand said cylinder and releasable means for holding 'said cylinder against unwinding, to permit said print to be dried by said heating unit. 50

HAROLD J. BRUNK.

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