US1946539A - Vacuum frame - Google Patents

Description

Feb. 13, 1934 D. v. MAzzocco VACUUM FRAME Filed Aug. 14, 1931 2 Sheets-Sheet l 1,.. ...EN m.; E

INVENTOR A/vrf L/ M/lzzocco wwd, C/uroj f 7mm/9 ATTORNEY-c Lw 1l HHH Li D Feb. 13, 1934. D. v. MAzzocco VACUUM FRAME Filed Aug. 14, 1931 2 Sheets-Sheet 2 l N V E N TO R A/vf ZIM/4220660 BY wmd'mb., *ma

ATTORNEYS Patented Fel). 1:3, 1934 UNITED STATES PATENT OFFICE Eureka Photo Mechanical Equipment, Inc.,

New York, N. Y., a corporation of New York Application August 14, 1931. Serial No. 557,027

16 Claims.

This invention relates to improvements in vacuum frames and devices facilitating the proper operationV thereof.

One of the objects of this invention is an improved vacuum frame and cooperating sealing washers.

Another object of the invention is an improved arrangement of a vacuum gauge with reference to the tube connecting the space between the vacuum frame and the sensitized metal press plate to the vacuum pump.

Still another object of the invention is the provision of mechanism by means of which the face of the negative carried by a negative frame will be brought into Contact at every point in its surface with the sensitized surface of the metal press plate.

Further objects consist in combinations of elements which insure the proper contact between a negative and sensitized surface of a press plate in the photocomposing machine.

Other objects will be apparent from the following description taken in connection with the drawings, in which Fig. 1 shows a vacuum frame in position in a photocomposing machine;

Fig. 2 is a section on the line 2 2 of Fig. 1;

Fig. 3 is a section on the line 3--3 of Fig. 1; and

Fig. 4 is a side view of the operating handle.

In the art of producing metal press plates it is the custom to employ a registration apparatus which is separate and distinct from a photocomposing machine inwhich metal press plates are produced from negatives which were registered in the registering apparatus. Registration is efiected in such a manner that when the negative is positioned in the photocomposing machine the registration marks on the negatives are in alignment with the travel lines of the photocomposing machine, and in accordance with the improvements shown in my application for a Registering apparatus, Ser. No. 556,759, led August 13, 1931, the negative is not only adjusted as above stated but also its face, when placed in the photocomposing machine, will be parallel with the sensitized surface of a metal press plate in the machine.

For the purpose of illustrating my invention I have shown a negative frame of the type shown in the application above referred to, and I have shown a photocomposing machine of the type shown in Letters Patent of the United States, No. 1,885,532, November 1, 1932. It is to be understood, of course, that certain features of the invention are obviously applicable to other types of photocomposing machines, and that the disclosure of a particular type of photocomposing machine is not to be considered as a limitation of my invention.

The photo mechanical machine shown in said patent, above referred to, includes supporting legs 1, 2, 3 and 4, Fig. 1, secured to carriage guide rails 5, 6 and 7, 8. Extending inwardly from the corners of the rectangle produced by these guide rails are supporting members 9, 10, 11 and 12 upon which is supported a rigid table base 13 carrying a table 14 upon which the sensitized press plate 15 is supported and to which it may be secured by the usual means, such as tape, not shown. The tape is used for the purpose of holding the metal press plate flat and in contact with the table 14. The rails 5 and 6 constitute guiding means for a carriage 16 toguide the carriage 16 so that the cross bars 17 will always move perpendicular to its length. The guide rails 7 and 8 support a carriage 18 and guide it in such e. manner that the cross bar 19 will always move in a line perpendicular to its length. The construction of the carriage and the guide rails is such that the cross bars 17 and 19 will always be perpendicularly related to each other, regardless of the position of the carriages on the guide rails. The cross bars 17 and 19 are provided with screw thread rack members 20 and 21 with which cooperate sleeves 22 and 23 which, respectively, surround the cross bars 17 and 19. These sleeves are provided with calibrations which cooperate with scales on the cross bars 17 and 19. The sleeves 22 and 23 are rotatably supported on brackets 24 and 25, connected to the legs of the outer member 26 of a negative frame supporting member, generally designated at 27, which also comprises an inner member 28, the two members of the negative frame supporting member being connected for vertical relative movement by slot and bolt connections 29, as indicated in Fig. 3. By means of this connection the inner frame member 28 may be moved relatively vertically with respect to the outer frame member 26 which is immovable vertically, being supported by means of rollers 30 running on the rack members 20 and 21 so that the negative frame supporting member 27 and negative frame, later referred to, may be moved horizontally and vertically, as is well understood. Jack screws 31, 32 and 33 are threaded into the outer member 26 which carries the brackets supporting the sleeves 22 and 23 and which carry spools 34 engaging the cross bars 17 and 19 by means of which the sleeves 22 and 23 may be moved into and out of engagement with the threads of the rack members 20 and 21 on the cross bars 17 and 19. When the jack screws are operated to disengage the threads the frame member 27 will be free to be moved with respect to the cross bars 17 and 19, until the pointers and 36 cooperate with the proper marks on the scales carried by the cross bars 17 and 19 to locate the negative approxi-f mately in the desired position, prior to the printing operation. After the adjustment of the carriage has been made the sleeves 22 and 23 are rotated until they are in the proper adjusted position, after which the sleeves are locked in their adjusted position by means of locking levers 37 and 38. By operation of the jack screws the threads on the sleeves 22 and 23 engage with the threads on the racks 20 and 21 on the cross rails 17 and 19, which are preferably shaped so that the negative will be cammed into the proper position as controlled by the position of the pointers 37 and 38 and the sleeves 22 and 23.

For the purpose of lowering and raising the negative frame, which I have here indicated at 40, which is suitably supported on the inner frame member 28 by means which will be described later, I provide the inner frame member with racks 41 which engage in spur gears 42 on a shaft 43 and a shaft 44 operated from the shaft 43, as indicated in Figs. 1 and 3. The shaft 43 is hollow and constitutes a part of the tube connection between the vacuum frame and a vacuum pump, not shown, connected to tube 44a, Fig. 3. The tube 44a extends into an opening in the operating handle 45 which is pivoted on a stud 45a on a crank 47 rigid with the tube or shaft 43. The crank 47 is provided with a port 48 connecting the tube 44a to the hollow shaft 43. The operating handle 45 is mounted on the crank 47 for relative movement with respect thereto, such movement being limited by the walls of the slot 49 in the operating handle `and a limiting bolt 46. A spring 50 on the bolt 46 holds the operating handle in contact with the crank 47. The operating handle is provided with a pin 51 which, as it is moved from the position shown in Fig. 1 in a clockwise direction into the position shown in Fig. 3, operates a bell crank 52 to disengage the same from the pair of projections 53 and 54 on one of the brackets 55 supporting the shaft 43 so that after communication is established between the tube 44 and the hollow shaft 43 the crank 47 and shaft 43 will be rotated by a further movement of the operating handle 45 to lower the inner frame member 28 and the vacuum frame 40 into the position shown in Fig. 2 in which the negative 56, carried by a vacuum frame, such as shown in my application Ser. No. 556,759, referred to, moves into contact with the sensitized surface of the metal press plate 15. The joint between the negative plate 56 and the frame 40 is preferably sealed by a sealing ring 57 of the general shape shown. For drawing the negative plate against the frame 40 and compressing the sealing ring 57 to secure a tight joint, I employ clamps 57a supported by a link pivot 57h and engaging over the edge of the negative as shown. As the clamp is drawn toward the frame, it draws or wedges the negative against the negative frame and compresses the sealing ring 57 to eect an air-tight seal. The construction of the clamps is such that they will automatically accommodate themselves to negatives of different thicknesses and size.

As shown in Fig. 2, the inner frame member 28 is provided with spherical seating members 58, preferably three in number, each of which is equipped with a xed threaded nut 59 into which securing bolts 60 are threaded when the vacuum frame is applied in the photocomposing machine. The bolts 60 are surrounded by sleeves 61 provided with semispherical lower ends 62 adapted to seat in said seating members 58, and with upper spherical ends 63, the construction being such that relative angular movement is permitted between the bolts 60 and sleeves 6l, as described in said application Ser. No. 556,759.

Surrounding each sleeve 61 is a split clutch sleeve 64 which cooperates with a clutch sleeve 65 so that when a nut 66 cooperating with the upper threaded portion of the sleeve is advanced the semi-spherical end 62 will be clamped during the registration operation into the proper position with respect to enlarged slots 67 in extensions 68 on the vacuum frame, and also will be held at the proper distance from the extensions 68 so as to present the face of the negative of the same or different thicknesses in absolute parallel relation with the face of the sensitized press plate 15 in the photocomposing machine. By means of this construction the negative will be aligned with the travel lines of the photocomposing machine and the face of the negative, regardless of any variations in thickness in the negative and will always make close contact with the press plate at every point in its surface.

In view of the fact that I have provided means by which a negative of unequal thicknesses may be brought down into contact with a metal press plate so that every part of its surface will be in contact therewith, the vacuum frame 40 in such a case will assume a non-parallel relation with 110 the metal press plate. This, of course, means that different portions of the flange 69, which cooperates with a sealing washer 70, will be at different distances from the metal press plate and that the sealing washer 116 will be under different amounts of compression at different points. Heretofore, the lower end of the flange 69 was made of considerable width and it has been found that the seal effected by such flange and cooperative washers heretofore 120 used therewith was ineffective at certain points, due to the fact that it required considerable force to compress the sealing ring. By means of the construction shown, the rubber between the end of the flange 69 and press plate may be put under 12B considerable pressure so that if the frame 40 is not exactly parallel with the press plate 15 the point at which the flange 69 is farthest away from the press plate 15 will effectively seal the vacuum frame at this point.

The depth of the V-shaped groove in the sealing ring 70 is less than the height of the flange 69 on the negative carrying frame, so that the flange may function to compress only the portions of the sealing ring directly underneath and to the same extent, or different extents, as a negative plate of equal or unequal thickness is forced against a sensitized plate in the photocomposing machine. This construction insures perfect sealing as the lower sealing face of the ring, when the latter is assembled on the flange, may be at a greater distance from the lower face of the negative carrying frame than in the constructions in which the edge of the flange has considerable width and larger area contact with the sealing 145 ring. The tapered construction of the flange and groove, while readily facilitating mounting and dismounting of the sealing ring on the flange, also provides for frictional engagement between the sides of the groove and the sides of 150 r mosphere.

the llange to retain the sealing ring on the flange without any other securing means during. the movement of the negative frame into position on the carriage frame, and during movement of the frame from position to position over -the sensitized plate. i

The rubber sealing ring is preferably made of the cross sectional shape shown in Fig. 2, and is relatively wide as at 71to extend into substantial contact with the main body of the negative frame to prevent the press plate from being drawn u-pwardly into the vacuum chamber of the negative frame as vacuum is applied. The sealing ring is also provided with a relatively high outer portion from which projects a flange 72 which closely hugs the iiang'e 69 to hold the ring in position on the vacuum frame 40. The sealing ring is also provided with a laterally extending flange 73 which is adapted to overlie the joint between the shade 79 and the outer portion of the' sealing ring to prevent transmission of light to any part of the sensitized surface lying outside of the sealing washer 70.

As shown in Figs. 2 and 3 the hollow shaft 43 is connected by means of a tube 75 to one side of the chamber in the vacuum frame. As usual, a gauge 'i6 is provided to indicate the amount of vacuum. As shown, I have connected this gauge by means of a tube '77 to the opposite side of the vacuum chamber so as to correctly register the amount of vacuum created between the frame and the sensitized plate. The amount of vacuum which may be created may be controlled by a valve '78 which is adjustable, as indicated.

My construction'provides' for a tight seal between the negative and the negative frame,` and between the sensitized press plate and the negative frame. lIhe construction of the outer sealing ring and cooperating partslis suchl that the negative moves into contact with every point in the portion of the surface of fthe sensitized plate directly opposite to it, as vacuum is applied. The parallel relation between the negative and the sensitized press plate is assured by the adjustment of the positioning posts, and in view of this relation the sensitized press plate will remain flat on the bed regardless of whether or not the negative is of the same thickness throughout. The outer sealing ring effectively prevents the press plate from being drawn into the vacuum charnber, and its outer flange prevents any light from passing between the shades and negative frame on to the sensitized press plate.

The location of the vacuum gauge with respect to the exhaust tube insures proper operation of the gauge to indicate accurately the condition in the vacuum chamber.

As the vacuum is turned on before the negative is lowered, a vacuum will be created as soon as the outer sealing ring becomes effective. After the printing operation, the movement of the handle toward the operator, Fig. 3, into the position shown in Fig. 4 operates to shut off the vacuum and connect the vacuum chamber to at- Upon further movement of the handle the negative frame and negative will be raised to permit adjustment opposite to a diiierent portion of the sensitized press plate.

While the invention has been described in connection with a photocomposing machine it is obvious, of course, that it is not limited to .Such machines, and that the plate 56 in the negative carrying frame may be either a negative or a positive. It is, therefore, to be understood that the expressions photocomposing and negative imported into the claims are to be considered as words of description and are not to be construed as limiting the claims to such machines and to negatives.

What I claim is:

1. The combination of a negative carrying frame, a tapered continuous flange on said frame extending downwardly and surrounding a negative plate on said frame, and a sealing ring provided with a V-shaped groove frictionally holding said ring on said ange when assembled.

2. The combination of a negative carrying frame, a tapered continuous flange on said frame extending downwardly and surrounding a negative plate on said frame, and a sealing ring provided with a V-shaped groove frictionally holding said ring on said ange when assembled, the depth of the V-shaped groove being less than the depth ofthe ange and the tapered edge of the flange being adapted to contact with the several portions of the bottom of said groove and press said portions of the ring directly under the iiange the same extent or varyingly as a negative plate of equal or unequal thicknesses is pressed against a sensitized press plate in photocomposing machine.

3. The combination with a negative carrying frame provided with a vacuum chamber, a downwardly directed flange, a sealing ring provided with a groove receiving said flange, and aportion on said sealing ring closing said vacuum chamber and having a face arranged in the plane of the face of a negative supported on said frame.

4. The combination with a negative carrying frame, a downwardly directed flange, a vsealing ring provided with a groove receiving said flange, and having a face adapted to engage the surface of the sensitized press plate, and a laterally extending annular projecting portion on said sealing ring overlying the outer edge of said face of the sealing ring.

5. Thel combination with a negative carrying frame, a downwardly directed flange on said frame, a sealing ring provided with a groove receiving said flange, and having a face adapted to engage `the surface of the sensitized press plate, an upwardly extending portion on said sealing ring lying against the outer face of said flange, and a laterally extending annular projecting portion on said sealing ring overlying the outer edge of said face of the sealing ring.

6. In combination with a photocomposing machine including a table for supporting a sensitized press plate, a carriage for supporting a negative carrying frame, means for lowering said carriage in a direction perpendicular to the plane of said table, and supporting means for supporting said negative carrying frame on said carriage in variable spaced relation thereto.

7. In combination with a photocomposing machine including a table for supporting a sensitized press plate, a carriage for supporting a negative carrying frame, means for lowering said carriage in a direction perpendicular to the plane of said table, and a plurality of supports for supporting different portions of said frame at different distances from said carriage to present the various portions of the face of a negative plate in the negative carrying frame into intimate contact with the sensitized surface of a press plate.

8. In combination with a photocomposing machine including a table for supporting avsensltized press plate, a carriage for supporting a negative carrying frame, means for lowering said carriage in a direction perpendicular to the piane of said table, a plurality of fixed seats on said carriage, a plurality of adjustable locating and spacing posts on said negative carrying frame. and means for locking said posts in spacing position.

9. In combination with a photocomposing machine including a table for supporting a sensitized press plate, a carriage for supporting a negative carrying frame, means for lowering said carriage in a direction perpendicular to the plane of said table, and supporting means for rigidly supporting said negative carrying frame on said carriage in variable spaced relations thereto, said negative carrying frame and sensitized press plate defining a vacuum chamber.

10. In combination with a photocomposing machine including a table for supporting a sensitized press plate, a carriage for supporting a nega.- tive carrying frame, means for lowering said carringe in a direction perpendicular to the plane of said table, supporting means for supporting said negative carrying frame on said carriage in variable spaced relations thereto, said negative carrying frame and sensitized press plate defining a vacuum chamber, an exhaust port communicating with one side of said chamber, and a vacuum gauge communicating with the other side of said chamber.

1l. In combination with a photocomposing machine including a table for a sensitized press plate, a negative carrying frame, means for supporting the frame for movement to and from the table, means providing a vacuum chamber between the negative carrying frame and sensitized press plate when in contact, vacuum producing means, and means for first connecting said vacuum producing means to said chamber and then lowering said frame and operable after a printing operation to disconnect said vacuum producing means, connect said vacuum chamber to the atmosphere and then raise said frame.

l2. An open rectangular vacuum frame for supporting a negative, said frame comprising side members of general U-shape in cross-section. the ends of the inner legs oi' said side members constituting a seat for a negative plate and the outer legs of said side members constituting a supporting means for a sealing ring for contact with a sensitized press plate, the space within said side members constituting a vacuum chamber.

13. An open rectangular vacuum frame for supporting a negative, said frame comprising side members oi general U-shape in crosssection, the ends of the inner legs of said side members constituting a seat i'or a negative plate and the outer legs of said side members constituting a supporting means for a sealing ring for contact with a sensitized press plate, said outer legs being tapered in cross-section to a point at the ends of said legs.

14. A combination with a vacuum frame for supporting a negative, said frame comprising a seat for a negative plate and a ilange surrounding said seat, of a sealing ring adapted to frictionally engage said flange, said sealing ring being provided with a face for contact with the sensitized press plate.

15. A combination with a vacuum frame for supporting a negative, said frame comprising a. seat for a negative plate and a iiange surrounding said seat, of a sealing ring adapted to frictionally engage said flange, said sealing ring being provided with a face for contact with the sensitized press plate and also with a portion extending toward said seat for the negative plate, said portion being provided with a surface lying in the plane of said face of the sealing ring.

16. A combination with a vacuum frame for supporting a negative, said frame comprising a seat for a negative plate and a flange surrounding said seat, of a sealing ring adapted to frictionally engage said flange, said sealing ring being provided with a face for contact with the sensitized press plate and also with a portion extending toward said seat for the negative plate, said portion being provided with a surface lying in the plane of said face of the sealing ring, said sealing ring also being provided with an out wardly extending flange surrounding the body portion of said ring and overhanging the outside edge of the main body of said ring.

DANTE V. MAZZOCCO.

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