US3460474A

US3460474A - Web feed roll for label printer

Info

Publication number: US3460474A
Application number: US651722A
Authority: US
Inventors: Dale C Follis; Duncan L Lampman
Original assignee: Diagraph Bradley Industries Inc
Current assignee: Diagraph Bradley Industries Inc
Priority date: 1967-07-07
Filing date: 1967-07-07
Publication date: 1969-08-12
Anticipated expiration: 1986-08-12

Description

D. C. FOLLIS ET AL WEB FEED ROLL FOR LABEL PRINTER Aug. 12, 1969 3' Sheets-Sheet 1 Filed July 7, 1967 Aug. 12, 1969 D. c. FOLLIS ET AL WEB FEED ROLL FOR LABEL PRINTER 3 Sheets-Sheet 2 Filed July 7, 1967 .LIL MIMI PL Aug. 12, 1969 m. c. FOLLIS ET Ah WEB FEED ROLL FOR LABEL PRINTER 5 Sheets-Sheet 5 Filed July 7, 1967 United States Patent US. Cl. 101-227 13 Claims ABSTRACT OF THE DISCLOSURE A label printer of the type having a printing and a feed roll for printing on and advancing a paper web from a supply roll to a guillotine shear where it is severed between successive label printings. The feed roll includes a raised portion of adjustable arcuate extent for adjusting the length of paper fed forward on each revolution thereof, only the raised portion of the roll having a radius sufficiently large to engage the web and pull it through between the printing and feed rolls. The feed roll is constituted by outer and inner concentric drums, with the inner drum being connected to an axial shaft. The raised portion is a blanket connected at one end to a bridging member over the outer drum, which member is interconnected to the shaft, and the other end passing through a slot in the outer drum and being connected to the inner drum. Thus, relative rotation between the outer and inner drums varies the arcuate extent of the portion of the blanket exposed on the outside surface of the outer drum, and, hence, varies the label length.

Background of the invention This invention pertains to printing apparatus, and particularly to an adjustable feed roll for label printing machines. The invention is particularly concerned with printing machines of the type employing a printing roll and a feed roll, which constitute a printing couple, for advancing and printing on a paper web fed thereto from a supply roll. The paper is severed between successive printings by a shear operated in timed relation to the printing couple. Since the length of the imprinted message on different labels varies considerably, means are provided for varying the length of paper advanced by the printing couple on each print cycle. Although adjustable feed rolls have been developed for this purpose, they have not proven entirely satisfactory under all conditions of use and for all purposes. For example, such devices are generally complex and difiicult to adjust, require the use of tools for performing the adjustment, and consume considerable non-productive machine time.

Summary of the invention The present web feed roll is comprised of a shaft with a hollow drum on the shaft, the drum having a longitudinal slot in its periphery. A bridge assembly is provided on the shaft including a bridge extending across the drum, and a blanket is secured at one end to the bridge and extends through the slot in the drum to its interior. The drum and bridge assembly are relatively rotatable on the axis of the shaft for varying the arcuate extent of the portion of the blanket exposed on the outer surface of the drum. Thus, the present invention prowides a feed roll for a label printer in which the label length is readily adjustable by varying the arcuate extent of the blanket exposed on the outer surface of the drum, which may be adjusted in a minimum of time, and which is characterized by simplicity of construction, low cost and ease of operation and use. Other objects and features will be in part apparent and in part pointed out hereinafter.

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Brief description of the drawings FIG. 1 is a longitudinal section of "the present label printer;

FIG. 2 is a plan view of the label printer of FIG. 1;

FIG. 3 is a longitudinal section of the present web feed roll;

FIG. 4 is a vertical section on line 4-4 of FIG. 3;

FIG. 5 is a vertical section similar to FIG. 4 showing the roll in a dilferent adjusted position; and

FIG. 6 is a vertical section similar to FIG. 5 showing an alternate form of the blanket.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Description of the prefer-red embodiment Referring to FIGS. 1 and 2 of the drawings, a label printer of this invention, generally indicated by reference numeral 1, is shown to comprise a housing 2 having a paper supply 3 at one end for feeding a web of paper 5 between an upper printing roll 7 and a lower feed roll 9, the rolls 7 and 9 constituting a printing couple. The paper web 5 issuing from the printing couple passes through a guillotine shear 11 for severing the printed labels into individual label lengths. The rolls 7 and 9 and the shear 11 are positively driven in timed relationship by a motor 13 and a drive mechanism gene-rally indicated at 15. An inking unit for inking the printing roll is indicated at 17.

Specifically, the paper supply 3 is comprised of a roll of paper stock 19 mounted for rotation on a spindle 21 cantilevered at the end of a bracket 23 bolted to the rear of the housing 2. A mandrel 25 is slidably received on the spindle 21 for positioning various widths of paper to center the web in the machine. The paper web 5 is maintained taut by a slack take-up bar 27 on the end of an arm 29 pivotally mounted on the spindle 21. The web 5 is guided over the top of the housing by a pair of guide flanges 31, each having a spring hold-down 30 for maintaining the web flat against the top of the housing. The we passes between the printing and feed rolls 7 and 9, respectively, where the web is printed and fed toward the shear 11. The printing roll 7 is comprised of a print ing drum 32 having either a stencil or rubber type printing plate 34 secured to its periphery. The drum 32 is supported at its ends by stub shafts 33, one of which is spring loaded to hold the drum in place for printing while permitting the drum to be removed or installed by withdrawing the shaft against the spring. The stencil or rubber type printing plate 34 is attached to the periphery of the printing drum by conventional clips and fasteners.

The inking unit 17 is comprised of an inverted bottle of ink 35, the neck of which is threaded in a socket 37 of an ink reservoir 39. An etched gravure inking roller 41 is journalled for rotation in the reservoir 39 for frictionally engaging the printing plate 34 on the periphery of the printing roll 7 thereby transferring ink from the reservoir to the plate as the rolls rotate. A doctor blade 43 is mounted adjacent the roll 41 for wiping excess ink therefrom. The pressure of the doctor blade on the roll 41 is adjustable by means of a spring biased thumb screw 45 for controlling the amount of ink transferred to the printing plate.

The web feed roll 9 has a raised rubber blanket 47, the arcuate extent of which can be varied to vary the length of paper fed forward on each revolution of the rolls 7 and 9. That is, on each revolution of the rolls a length of paper (the label length) is fed forward corresponding to the arcuate extent of the raised rubber blanket since only this portion of the feed roll has a .radius sufliciently large to engage the paper web and squeeze it against the printing roll. If the arc is reduced, the label length is decreased; if the arc is increased, the label length is increased. The manner in which the blanket 47 is adjusted will be hereinafter set forth.

The printing and feed rolls 7 and 9 are simultaneously driven in opposite directions by the drive mechanism 15 which includes a chain 49 driven from a speed-reducing gear box 51 connected to the output of the motor 13. The paper web issuing from the printing couple is fed to the shear 11, the latter being constituted by a fixed blade 53 over which the web passes, and a reciprocable blade 55, the latter being carried by an arm 57 interconnected to a linkage assembly 59 driven from a cam assembly 61. As illustrated in FIG. 1, the drive chain 49 drives the cam assembly 61 for simultaneous operation of the shear and printing couple. The printer is designed to print on a maximum of 270 degrees of the print cycle and to cut off or shear the web while it is stationary during the last 90 degrees. Thus, the shear is operated from the printing couple d-rive once each revolution of the rolls during the dwell interval of the paper when the raised blanket 47 is out of contact with the paper. Accordingly, the paper is intermittently fed forward in label lengths, the lable length being varied by varying the arcuate extent of the blanket 47, and the label lengths fed forward on successive revolutions of rolls 7 and 9 are severed by the shear 11.

Referring to FIGS. 3-5, the web feed roll 9 comprises a shaft 63 having a sprocket 65 secured at one end by a set screw 67, the drive chain 49 being trained around the sprocket for driving the roll. An outer drum 69 is mounted for rotation with and relative to the shaft 63 by an integral head 71 and hub 73 at one end and a disk 75 at the other end, the disk being pinned to the shaft 63 and having a shoulder 77 rotatably receiving the end of the drum. An adjusting knob 78 is secured to the hub 73 and a knurled lock nut 79 is threaded on the end of shaft 63 for locking the shaft and outer drum together. A bridging assembly including an arcuate bridge plate 81 extends across the drum 69 and is secured at one end to the disk 75 and at the other end to a collar 84 in which hub 73 is rotatable. As illustrated in FIGS. 4 and 5, a longitudinal slot 87 is formed in the periphery of the drum 69 adjacent one side of the bridge 81.

In the interior of the drum 69 is an inner drum 89 resiliently interconnected with the shaft 63 by a spiral spring 91 secured at one end to the shaft by a screw 93 and at the other end to the inner wall of the drum 89 by a projecting tab 95. The drum covering or blanket 47 is secured at one end 97 to the bridging member 81, wraps around a portion of the periphery of the outer drum 69, and passes over a guide roller 99 and through the slot 87 to the interior of the drum 69. The other end 100 of the blanket is secured to the inner drum 89 by a clip 101 welded thereto. The blanket 47 constitutes the raised portion of the feed roll 9 which engages the paper web and advances it through the label printer. It is preferably formed of rubber, although other materials such as plastic or leather may be suitable. The hub 73 and the end of the shaft opposite the hub are journalled in bearings 103 in the side walls 105 of the housing.

An alternate form of the blanket 47 is illustrated in FIG. 6 as comprising a plurality of separate rubber layers 107, 109 and 111 lying in face-to-face slidable contacting relation through the longitudinal extent of the blanket. Outer layers 107 and 109 are continuous and are looped through an opening 113 in the end of bridge 81 for securing the blanket to the bridge. The inner layer 111 is sandwiched between the outer layers. This arrangement provides a smoother retraction of the blanket into the outer drum than the solid blanket, and a convenient method of afiixing the end of the blanket to the bridge.

To operate the printer 1, a roll of paper 19 is mounted on the spindle 21 and the web 5 is guided under the bar 27 and between the guides 31. A suitable printing plate 34, of either the stencil or raised rubber type, is secured to the periphery of the printing drum 32 and the web 5 is threaded between the rolls 7 and 9 and between

blades

53 and 55 of guillotine shear 11. The motor 13 is then energized to drive the rolls 7 and 9 and the guillotine shear 11 in timed relationship via the chain 49 and linkage system 59. Thus, a length of paper web 5 is drawn through the printing couple corresponding to the arcuate extent of the raised portion 47 of the roll 9. As the web passes between the raised portion of the roll 9 and the printing plate 34, the web is pressed against the printing plate and imprinted with the desired message. When the raised portion 47 of the feed roll 9 rotates out of contact with the paper web 5, the printing couple continues to rotate but the paper web remains stationary. At the proper interval during this dwell of the paper, the blade 55 of the guillotine shear 11 is reciprocated to sever the paper at the desired label length.

When the first few labels of each run are printed and severed into label lengths, the web feed roll '9 is adjusted to advance to the shear 11 the desired length of paper corresponding substantially to the length of the imprinted message. This is accomplished by varying the arcuate extent of the raised rubber blanket 47 on the periphery of the roll '9 since only this part of the feed roll has a radius sufficiently large to engage the paper web and drive it against the printing roll. To adjust the roll 9, the knurled nut 79 is loosened, thereby feeding the outer drum 69 for rotation with respect to the shaft 63 and inner drum 89. The adjusting knob 78 is then rotated to rotate the outer drum '69 and slot 87 nearer to or further from the bridge plate 81. As the drum and slot rotate, the shaft 63 and inner drum 89 remain stationary and the length of rubber blanket wrapped around the outer drum is either increased or decreased depending upon the direction of rotation of the outer drum. To increase the arcuate extent of the blanket 47 and hence increase the label length, the knob 78 is rotated such that the slot 87 rotates in a clockwise direction as viewed in FIGS. 4 and 5. Thus the slot 87 rotates clockwise from the FIG. 5 to the FIG. 4 position and the blanket 47 passes over the guide roller 99 and is wrapped around the outer drum 69. When the desired arcuate extent is obtained, the knurled nut 79 is tightened to lock the outer drum 69 to the shaft 63 by forcing the end of the drum against the shoulder 77 on the disk 75. This insures rotation of the entire feed roll assembly as an integral unit when the sprocket is turned. The spiral spring 91 between the shaft 63 and the inner drum 89 maintains the rubber blanket 47 taut while the outer drum is being adjusted and takes up the slack which would otherwise result as the portion of the blanket to be wrapped around the smaller diameter of the inner drum increases. If a shorter label length is desired, the knurled nut 79 is loosened and the knob 78 is rotated in the opposite direction, thereby causing the outer drum 69 and slot 87 to rotate counterclockwise from the FIG. 4 to the FIG. 5 position and cause a portion of the blanket 47 to be covered by the outer drum 69 as it is wrapped around the inner drum 89. The arcuate distance A illustrated in FIGS. 4 and 5 corresponds to the length of paper fed forward on each revolution of the printing couple. Thus, as clearly indicated, the length of the label fed with the roll adjusted to the FIG. 4 position is considerably greater than that with the roll adjusted to the FIG. 5 position.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

What is claimed is:

1. A web feed roll comprising:

a shaft,

a hollow drum on the shaft, said drum having a longitudinal slot in its periphery,

a bridge assembly on the shaft including a bridge extending across the drum, and

a blanket having one end secured to the bridges and extending through the slot to the interior of the drum,

said drum and bridge assembly being relatively rotatable on the axis of the shaft for varying the arcuate extent of the portion of the blanket exposed on the other surface of the drum.

2. A feed roll as set forth in claim 1 further comprising means within the drum connected to the inner end of the blanket for maintaining the blanket taut.

3. A feed roll as set forth in claim 2 wherein said means comprises an inner drum resiliently connected to said shaft.

4. A feed roll as set forth in claim 1 wherein said bridge is comprised of an arcuate plate interconnected to said shaft.

5. A feed roll as set forth in claim 4 further comprising a disk secured to said shaft at one end of said drum, said arcuate plate being secured to the periphery of said disk.

6. A feed roll as set forth in claim 1 further comprising a guide roller mounted for rotation in the interior of said drum adjacent one side of said slot.

7. A feed roll as set forth in claim 1 wherein said blanket is formed of rubber.

8. A feed roll as set forth in claim 1 wherein said blanket comprises a plurality of separate rubber layers lying in face-to-face slidable contacting relation.

9. A feed roll as set forth in claim 8 wherein said bridge has an opening therein, and said blanket includes a continuous outer layer looped at one end through the opening in said bridge, and at least one inner layer sandwiched between the looped outer layers.

10. A feed roll as set forth in claim 1 further comprising means for locking said drum and shaft together for concomitant rotation.

11. A feed roll as set forth in claim 10 wherein said locking means comprises a hub on said drum coaxial with said shaft, the shaft having a threaded end receiving a nut for locking said hub to said shaft.

12. A printing machine comprising means for guiding a Web to a printing couple, said printing couple comprising a printing roll having a printing plate secured to its periphery and a feed roll having a raised portion of adjustable arcuate extent on its periphery, means for rotating said printing and feed rolls for drawing said Web therebetween, and a shear receiving the paper from said printing couple for severing it at intervals, said shear being driven in timed relationship with said printing couple, said feed roll including a shaft, a drum having a longitudinal slot in its periphery, a blanket extending through said slot into the interior of said drum, a por tion of said blanket covering the outer surface of said drum and constituting said raised portion, and means for varying the length of the portion of said blanket on the outer surface of the drum.

13. A printing machine as set forth in claim 12 wherein said means for varying includes a bridge on the exterior of said drum secured to one end of said blanket, and means for permitting rotation of said drum relative to said shaft.

References Cited UNITED STATES PATENTS 259,735 6/1882 Welker 226-440 630,270 8/ 1899 Sobinski 226- 2,713,304 7/1955 Thomas 10l227 X 3,401,630 9/1968 Goodrich et al 10'l-228 ROBERT E. PULFREY, Primary Examiner I. REED FISHER, Assistant Examiner US. Cl. X.R.