US2850214A

US2850214A - Pneumatic dry powder offset eliminator

Info

Publication number: US2850214A
Application number: US567655A
Authority: US
Inventors: Jr George F Rooney
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-02-24
Filing date: 1956-02-24
Publication date: 1958-09-02
Anticipated expiration: 1975-09-02

Description

' Sept. 2, 1958 s. F. ROONEY, JR 2,850,214

PNEUMATIC DRY POWDER OFFSET ELIMINATOR Filed Feb. 2A, 1956 2 Sheets-Sheet 1 LNVENTOR. GEORGE E Roo/vsxJ/e;

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Sept. 2, 1958 G. F. ROONEY, JR

PNEUMATIC DRY POWDER OFFSET ELIMINATOR 2 Sheets-Sheet 2 Filed Feb. 24, 1956 NM \m x| 6 mm M mu Rm m mm 0 o vb .W Wm mw w \m W) M m u m m JNW IN VEN TOR. GEORGE E ROONEYJR.

PNEUMATIC DRY POWDER OFFSET ELIMINATOR George F. Rooney, In, (Iincinnati, Ohio Application February 24,1956, Serial No. 567,655 2 Claims. (Cl. 222-493) This invention relates to a device for spraying powder particles on printed sheets as the printed sheets are delivered by a printing press, to prevent undesired oifset printing.

An object of this invention is to provide a device for spraying powder having a container in which powder particles are sufiiciently agitated to form a mist or suspension in the container at a level above the normal level of the body of powder therein, the mist of powder being discharged from the container into distributing lines 'from which discrete puffs of powder issue.

A further object of this invention is to provide a device of this type in which air is introduced into a powder container in two streams one into the body of the powder to agitate the same and the other into the air-powder suspension to discharge the same into the distribution lines.

A further object of this invention is to provide a device of this type in which an air inlet line discharges into the lower portion of the container below the powder level in such a direction as to stir the powder by driving the powder circumferentially of the container.

A further object of this invention is to provide a novel and efiicient mechanism for operating an air supply valve for the container whereby discrete pufis of powder particles are delivered to printed sheets issuing from the printing press in timed relation therewith and air for agitating the powder is provided.

A further object of this invention is to provide a device of this type having an air line, a valve therein for delivering air to the powder in the container, and a mechanism for operating the valve at timed intervals to eifect delivery of discrete puffs of powder particles to printed sheets in timed relation to the delivery of the sheets by the press.

The above and other objects and features of this invention will be apparent to those having ordinary skill in the art to which this invention pertains, from the following detailed description and the drawings:

In the drawings:

Figure 1 is a perspective view showing a powder spray ing device constructed in accordance with an embodiment of this invention, the device being shown mounted at the delivery end of a printing press, only a fragmentary portion of the printing press being shown.

Fig. 2 is a view in vertical section of the powder container of the device;

Fig. '3 is a view in section taken on the line IIIIII in Fig. 2;

Fig. 4 is a fragmentary view in section, taken on the line IVIV in Fig. 2;

Patent Fig. 5 is an enlarged view in side elevation of the valve and valve operating mechanism of the device illustrated in Figs. 1, 2, and 3;

Fig. 6 is a view in side elevation of the valve and valve operating mechanism in another position; and

Fig. 7 is a view in side elevation showing the valve and valve operating mechanism in a further position.

ice

In Fig. l the delivery end of a printing press is indicated at 10. Details of construction of the printing press are omitted and only as much of the delivery end of the press is shown as is necessary for an explanation of the invention. At the delivery end of the printing press, piles of printed sheets 12 are accumulated on sheetholding boards 14. The boards 14 are supported on beams 16 which are gradually lowered as the stack of sheets gets higher and higher. Also at the delivery end of the press are frame members or posts, two of which are indicated at 17 and 18. The frame member or post 17 supports a crank 19 which swings in timed relation with the delivery of printed sheets. The mechanism described to this point forms a part of printing presses which are presently in common use for printing box board and the like.

On post 17 is mounted a bracket 21 which supports a powder container 23 into the chamber of which air under pressure is delivered by an air valve 24 disposed in an air supply line 26. The air passes through an air filter 27 and a pressure reducing valve 28. From the air valve 24, the air passes through a T-fitting 29 to

lines

31 and 32 leading to the upper part and the bottom of the container, respectively. Powder from the container 23 is distributed by powder distributing lines 34 having nozzles 36 at the discharge ends thereof. The nozzles 36 are disposed above the pile of sheets 12 and are arranged to distribute powder on the sheets as they are delivered from the press.

The air valve is actuated by valve operating mechanism indicated generally at 38, that is actuated by the crank 19. As the crank 19 swings to the right, as indicated in Fig. l, the valve is opened to provide an air blast to the container. The air delivered to the bottom of the container agitates the powder and forms an air-powder suspension in the upper part of the container. The air blast delivered by pipe 31 distributes the powder-air suspension to the printed sheets. As the crank 19 swings back to the left, the air supply and consequently the dis- The powder container The powder container 23, as illustrated in Fig. 2, includes a fiat bottom plate 41 and an upright cylindrical wall 42. At the upper end of the cylindrical wall 42 is an outwardly extending flange 43. The powder container is closed by a cap 44 which is sealed to the flange 43 by an appropriate gasket 46. A stud 47 attached to the bottom plate 41 extends upwardly through the container. A nut 48 on the stud 47 holds the cap 44 in closed position.

The air inlet line 351 communicates with the upper portion of the interior of the container through an opening 49 in the wall thereof. The powder distributing lines 34 communicate with the upper portion of the container through openings 51. The powder distributing lines are opposite the air inlet opening 49 'so that the flow of air from pipe 31 to lines 34 crosses the upper portion of the container. The air inlet opening 49 and outlet openings 51 are horizontal and substantially aligned so that the blasts or puffs of air drive powder mist directly across of the powder distributing lines may be used as'desired or the needs require.

The air supply line 32 has a needle valve 52 therein. From the needle valve 52 air passes through a nipple 53 which extends through an opening 54 in the lower portion of the container. An elbow fitting 56 is mounted on the inner end of the nipple 53, and, as shown in Figs. 2 and 4, extends downwardly and circumferentially of the container at an angle of approximately 45 to the vertical. Thus, air delivered by line 32 and elbow fitting 56 is discharged downwardly and circumferentially to stir up and agitate the powder in the container so that a mist or suspension of air and powder is formed above the normal level of powder in the container. This mist of powder is discharged to the distribution lines 34, in the manner stated supra, to the nozzles 36. As indicated in Fig. 1, nozzles 36 are supported on an appropriate frame 57 which extends above the printed sheets so that the powder is distributed onto the sheets as the sheets are stacked.

The needle valve 52 is opened only slightly, so that the major portion of air passing through the air valve 24 enters through the line 31 to provide a substantial puff for driving air through the lines 34. The amount of powder that is distributed with each puff may be controlled by adjusting the opening of the needle valve 52 to increase or decrease the degree of agitation of the powder and the density of the powder mist in the upper part of the chamber of container 23.

Powder is maintained in the container at levels between a minimum level A and a maximum level B (see Fig. 2). At all times there is a chamber space above the powder level in communication with the

openings

49 and 51. In addition, the level of powder is maintained above the elbow 56 so that the powder-agitating air is discharged below the powder level into the powder.

An electric heater 57a is attached to the wall of the container and serves to keep the powder in the container warm and prevent condensation of moisture inside the container.

The air valve The operation of the air valve 24 and the valve actuatin mechanism 38 is most clearly shown in Figs. -7 inclusive. The air valve 24 has an air inlet 58 and a discharge 59. A plunger 61 actuates the air valve. The plunger 61, in turn, is actuated by an upright lever 62 which is pivotally attached at its lower end to the hous ing of the valve. pivotally mounted a head member 63. The head member 63 is .provided with a bore 64 through which a rod 66 extends. The rod 66 is Z-shaped and has

arms

66a and 66b and a cross bar 660. Arm 66a may be adjusted along the bore 64. The rod is held in adjusted position by a set screw 67. Adjustment of the rod along the bore 64 determines the time of the start of powder delivery.

A stop rod 72 is attached to the head member 63 and is engageable with a lug 73. The lug 73 is mounted on an adjustable bar 74 mounted on the body of the air valve. Bar 74 is slotted, as indicated at 75, so that the bar 74 can be adjusted to either raise or lower the position of the lug 73. The stop rod 72 engages the lug 73 when the valve actuating lever 62 and the rod 66 are in the position shown in full lines in Fig. 5. Adjustment of bar 74 determines the end of powder delivery.

The valve-actuating crank 19 is provided with a lug 76 at the upper end thereof. The lu 76 is engageable with the cross bar 600 of the rod 66. The crank 19 is driven by a rod 77, only a portion of which is shown, forming a part of the printing press mechanism. Rod 77 rec1procates back and forth in timed relation to the delivery of printed sheets and swings the crank 19 with an oscillating motion. Thus, the crank 19 oscillates in timed relation with the operation of the sheet delivery mechanism of the printing press.

At the upper end of the lever 62 is When the crank 19 is in the position shown in dot-dash lines in Fig. 5, lug 76 engages arm 66b of the rod 66 and holds the rod in raised position. The crank 19 swings to the right to the position shown in full lines in Fig. 5 and through that position to the position shown in Fig. 6 in which the lug 76 engages the cross bar of the rod 66 to urge the rod and the valve actuating lever to the right to actuate the valve and permit air to pass through the valve.

As the crank 19 advances farther to the right, the lug 76 passes below the lower end of the cross bar 66a, and the rod 66 rides on the crank as shown in Fig. 7, whereupon the valve 24 is closed by actuation of the valve spring (not shown) of the valve. Then, the crank 19 swings back to the left to the position shown in dot-dash lines in Fig. 5, whereupon the cycle is repeated.

Conclusion As sheets are delivered from the printing press, air is directed into the powder container 23 in puffs, so that, as each sheet is delivered, a puff of powder is distributed to the sheet to coat the sheet and prevent offset printing.

The air valve and piping arrangement provide two supplies of air to the powder container. One supply is directed into the lower portion of the container to stir and agitate the powder so that a mist or suspension of powder is formed in the upper portion of the container. The other air supply is directed into the upper portion of the container and eifects delivery of the mist to the nozzles.

The powder used may be of the type usually used in preventing offset printing.

The construction of the device is very simple. However, the device causes uniform delivery of a puff of pow der to each sheet, notwithstanding variations in level of powder in the container.

The powder spraying device illustrated in the drawings and described above is subject to structural modification without departing from the spirit and scope of the appended claims.

Having described my invention, what I claim as new and desire to secure by letters patent is:

1. A device for spraying powder particles which comprises an enclosed, upright, hollow, cylindrical, powderholding container having its interior substantially free of obstructions and having a flat, horizontal bottom plate, powder partially filling the container, a horizontal air inlet in the upper portion of the wall of said container for discharging air across the upper portion of the interior of the container above the level of the powder, a powder distributing line in communication with the interior of the cylinder and positioned in the opposite wall of said container, said distributing line being in substantially the same horizontal plane as the air inlet whereby powder in the container between said air inlet and said powder distributing line is forced through said distributing line, another air inlet adjacent the lower end of the container below the powder level, means attached to the lower air inlet for directing air therefrom circumferentially of the container, means for supplying timed puffs of air to the air inlets whereby powder is stirred and forced between the upper air inlet and the discharging line, means for connecting said air inlets together and means for throttling the flow of air into said lower air inlet to control the degree of agitation of the powder in the container.

2. A device for spraying powder particles as defined in claim 1 in which said lower inlet is directed downwardly and circumferentially of the container.

References Cited in the file of this patent UNITED STATES PATENTS 1,592,806 Brunell July 13, 1926 2,257,010 Hildebrand Sept. 23, 1941 2,496,194 Bennett Ian. 31, 1950 2,720,342 Fleck Oct. 11, 1955 2,729,194 Jones Ian. 3, 1956