US2860578A

US2860578A - Head registration adjusting mechanism for duplicators

Info

Publication number: US2860578A
Application number: US610744A
Authority: US
Inventors: John L Tregay
Original assignee: AB Dick Co
Current assignee: AB Dick Co
Priority date: 1956-09-19
Filing date: 1956-09-19
Publication date: 1958-11-18
Anticipated expiration: 1975-11-18

Description

` ov; 18,` 1958 y J. L. TREGAY 2,860,578

' ,REGISTRATION DJUSTING IIECHANISI FOR DUPLICATORS rund sept. 19', 195s INVENTOIL lll United States Patent OY,

HEAD REGISTRATION ADIUS'I'ING MECHANISM t FOR DUPLICATORS John L. Tregay, Broadview, lll., assigner to A. B. Dick Company, Niles, lll., a corporation of Illinois Application .september-*19, 19s6,seria1 No. 610,144

1 Chim. (ci. rc1-24s) This invention relates to printing machines or duplicators and pertains particularly to a mechanism for adjusting the head registration. By head registration is meant the position of the printed matter with respect to the head of the sheet printed on the duplicator.

Thus, one principal object of the present invention is to provide a new and improved head registration adjusting mechanism for duplicators.

A further object is to provide a new and improved head registration adjusting mechanism which is applicable to all types of duplicators but is especially advantageous when used in connection with a three-cylinder offset printing machine utilizing the lithographie process.

Another object is to provide a new and improved head registration adjusting mechanism whereby the positions of the blanket and master cylinders of a threefcylinder machine may be changed relative to the position of the impression cylinder, without changing the relative positions of the blanket and master cylinders.

A further object is to provide a new andv improved head registration adjusting mechanism whereby the blanket cylinder is readily and positively located in the position for effecting the adjustment and is maintained stationary in this position while the adjustment is being made.

It is a further object to provide such a new and improved head registration adjusting mechanism in which a slidable'and rotatable wrench is adapted to extend through a locating aperture in a positioning member on the blanket cylinder, so as to align the wrench with a rotatable adjusting member, while maintaining the blanket cylinder stationary.

Another object is to provide a new and improved adjusting mechanism which greatly facilitates the head registration adjustment.

A further object is to provide a new and improved head registration adjusting mechanism which is effective and convenient in operation, yet is relatively simple and low inv cost.

Further objects and advantages of the present invention will appear from the following description, taken with the accompanying drawings, in which:

Fig. 1 is a diagrammatic side view of a lithographie oiset printing machine or duplicator equipped with a head registration adjusting mechanism which constitutes an illustrative embodiment of the present invention.

Fig. 2 is an elevational view, partly in section, generally along a line 2-2 in Fig. 1, showing the offset cylinder of the three-cylinder printing machine.

Fig. 3 is a diagrammatic sectional view, taken generally along a line 3 3 in Fig. 2, and showing the gears which connect the three cylinders of the printing machine.

Fig. 4 is a fragmentary enlarged sectional view taken generally along a line 4-4 in Fig. 2.

Fig. 5 is a sectional view taken generally along a line 5-5 in Fig. 2.

Fig. 6 is an enlarged elevational view of the indicia 2,860,578 Patented Nov. 18, 1958 'ice 2 carried by the gears on the blanket cylinder, the same indicia being shown on a smaller scale in Fig. 2.

As already indicated, the drawings illustrate a threecylinder printing machine or duplicator 10 (Fig. l), which may be of the lithographic offset type. However, it will be understood that the present invention is also applicable to duplicators of4 other types and having any suitable number of cylinders.

The offset duplicator 10 of Fig. 1 is equipped with an olset or a blanket cylinder 12 which is engageable with a master cylinder 14 and an impression cylinder 16. It will be understoodl that the master cylinder 14 is adapted to hold a master sheet or plate on which an ink image of the printed matter or the like is formed. The ink image is transferred to a blanket 18, wrapped around the blanket cylinder 12. From the blanket 18, the image is again transferred to a sheet of paper fedV between the blanket and

impression cylinders

12 and 16. blanket 18 may be made of rubber or other suitable composition.

The

cylinders

12, 14 and 16 are rotatable and are adapted to be driven in unison by gearing or the like now to be described. In the illustrated embodiment, a gear 20 is secured to one end of the blanket cylinder 12 and is arranged to mesh with a gear 22 fixed on one end of the master cylinder 14. The blanket cylinder 12 also carries a ring gear 24 which is adjustable in angular position relative to the gear20. The adjustable ring gear 24 meshes with a gear 26 secured to the impression cylinder 16. A suitable motor, not shown, may be arranged to drive any of the three cylinders, usually the blanket cylinder 12. In the illustrated machine, the cylinders may be rotated manually by turning a hand wheel 28 mounted on a shaft 30 which carries a pinion 32, meshing with the ring gear 24.

The adjustable ring gear 24 may be mounted on the blanket cylinder 12 in various ways. ln the illustrated case, the ring gear 24 is slidably received around a reduced, cylindrical end portion 31 (Fig. 5) on the gear 20. It will be seen that the ring gear 24 has a cylindrical inner surface 33 which fits around the reduced portion 31. The first gear 20 is,also ring-shaped in form and is arranged to tit closely over a reduced portion 34 on the blanket cylinder 12. The

gears

20 and 24 have at interengageable end faces 3 6 and 38.

Cylindrical surfaces

40 and 42 are formed on the gears 2t) and 24 adjacent the end faces .36 and 38. Indicia may be inscribed on the surfaces 4G and 42 to indicate the relative angular positions of the

gears

20 and 24. In this case, the indicia include an index mark 44 on the gear 20 and a scale 46 on the gear 24.

The ring gear 24 is adapted to be held against the gear 20 by a ring-shaped clamping plate 48 which is engageable with an end face or shoulder 52 formed on the outer end of the ring gear. It will be seen that the clamping plate 48 lits around the reduced portion 34 on the cylinder 12.

The clamping plate 48 is adapted to be clamped against the ring gear 24, by means now to be described. When the ring gear is thus clamped, it is held against the gear 20 and thus is immovable with respect to the blanket cylinder. Accordingly, the gear 24 rotates with .the blanket cylinder and completes the driving connection between the impression cylinder 16 and the blanket cylin der 12.

In the illustrated construction, the plate 48 is adapted to be clamped against the ring gear 24 by a pull-rod 54 having a reduced, threaded end portion 56 which extends through the plate 48. A nut 58` is screwed on to the end portion 56 and securely tightened to hold the rod 54 in lixed relation to the plate 48. The pull rod 54 is slidable in an opening 60 formed in the gear 20,-and

The l in a series of aligned,

longitudinal bores

62, 64, 66 and 68 formed in the blanket cylinder 12. It will be seen that the rod S4 extends lengthwise entirely through the blanket cylinder 12. Thus, the bore 68 extends through an end wall 70 at the opposite end of the cylinder from the adjustable ring gear 24. The rod 54 extends through the bore 68 and has an externally threaded end portion 72 projecting beyond the end wall 70. A rotatable clamping member in the form of a nut 74 is screwed onto the end portion 72. Thus, the gear 24 is clamped and unclamped byl tightening and loosening the nut 74.

The nut 74 is adapted to be operated by a special wrench '76. To poxition the blanket cylinder 12 so that the nut 74 will be aligned with the wrench 76, the cylinder 12 is provided with a positioning plate or disk 78 which is secured to the end of the cylinder 12 and is spaced outwardly from the nut 74. A locating hole or opening 80 is formed in the positioning plate 78 opposite the nut 74.

By means now to be described, the wrench 76 may be moved against the positioning plate 78 and through the locating hole 80, so as to engage the nut 74. It will be seen that the nut 74 and the wrench 76 are provided with complementary formations which are adapted to interlock so as to transmit torque from the wrench to the nut. In the illustrated construction, the nut has a pair of radial lugs or blades 82 projecting from the outer end thereof, while the wrench 76 is formed with a ker'f or slot 84 adapted to receive the lugs 82. The wrench 76 has a cylindrical outer surface 86 to tit through the locating hole 80.

It will be seen that the wrench 76 is fixed on one end of a shaft 88 which is rotatable and slidable in a xed guide 90. A handle or hand wheel 92 is mounted on the other end of the shaft. wardly, the wrench 76 may be advanced against the positioning plate 78. A spring 94 is arranged between the guide 90 and the shaft 88 so that the wrench 76 will normally be biased away from the positioning plate 78.

The limits of the relative movement between the gear 24 and the gear 20 are defined by pins 96 and 98 which extend outwardly from the outer face of the clamping plate 48 and are engageable by a radial arm 110, rotatable with the ring gea-r 24. In this case, the outer end of the arm 110 fits into a notch or slot 102 defined between bosses or lugs 104 and 106 on the outer end of the adjustable ring gear 24. The arm 110 may be employed to drive various cams or the like, not shown.

When it is desired to make the registration adjustment, the handle 92 is pushed inwardly to advance the wrench 76 against the positioning plate 78. Next, the hand wheel 28 is rotated so as to turn the blanket cylinder 12 until the locating hole 80 comes into alignment with the wrench 76. Pressure is maintained on the handle 92 so that the wrench 76 will immediately enter the locating hole 80. The wrench 76 thereby locks the blanket cylinder 12 against rotation. By turning the handle 92, the kerf 84 on the wrench may be engaged with the lugs 82 on the nut 74. Then, the handle 92 may be turned to loosen the clamping nut 74. This relaxes the tensionv registration. When the desired adjustment has been "chieved, the handle 92 is rotated so as to tighten the nut 74 and thereby clamp the gear 24 to the blanket cylinder 12. The handle 92 is then released, whereupon the spring 94 retracts the wrench 76 out of engagement with the nut 74 and the positioning plate 78'.

By pushing the handle 92 in Since the relative positions of the blanket and master cylinders 12 and 14 are not changed, the image is transferred from the master to the blanket cylinder as before, and there is no need to clean the blanket 18 on the cylinder 12.

It will be appreciated that the head registration adjustment may be made very quickly and easily. Moreover, the adjustment may be made with great accuracy by referring to the indicia on the

gears

20 and 24.

Various modifications, alternative constructions, and equivalents may be employed without departing from the true spirit and scope of the present invention, as exemplified in the foregoing description and defined in the following claims.

I claim:

1. In a printing machine, the combination comprising a master cylinder, an otset cylinder engageable with said master cylinder, an impression cylinder engageable with said offset cylinder, a first gear secured to one end of said olset cylinder, a second gear meshing with said first gear and secured to said master cylinder, a third gear mounted on said olset cylinder adjacent said trst gear for angular adjustment relative to said oset cylinder, a fourth gear meshing with said third gear and secured to said impression cylinder, a clamping plate engageable with said third gear for disengageably clamping said third gear against said first gear, indicia on said first and third gears to indicate the relative angular positions thereof, a rod secured to said clamping plate and extending longitudinally through said offset cylinder, said rod having a threaded end portion extending outwardly beyond the opposite end of said otset cylinder, a nut screwed onto said threaded end portion for tensioning said rod and thereby clamping said third gear, a positioning plate secured to said opposite end of said offset cylinder and having a locating hole therein positioned opposite said nut, a wrench movable against said positioning plate and through said hole into engagement with said nut, said wrench and said nut having complementary formations adapted to interlock for transmitting torque between said wrench and said nut, a shaft supporting said wrench and having handle' means thereon, means supporting said shaft for rotation and sliding movement toward and away from said positioning plate, and spring means biasing said shaft away from said positioning plate.

2. In a registration adjusting mechanism for a printing machine, the combination comprising a rotatable printing cylinder, a gear mounted thereon for angular adjustment relative thereto, an operating member mounted on said cylinder for rotation relative thereto, means on said cylinder and operable by said member in response to rotation thereof for disengageably locking said gear to said cylinder, a positioning plate secured to said cylinder and having a locating hole therein opposite said operating member, a wrench mounted adjacent said cylinder for rotati-on and translatory movement against said plate and through said hole into engagement with said operating member, the reception of said wrench in said hole being effective to locate said cylinder in a stationary position with said operating member aligned with said wrench, said wrench and said operating member having complementary interengageable formations thereon for transmitting torque between said wrench and said operating member, and means -biasing said wrench away from said plate.

3. In a registration adjusting mechanism for a printing machine, the combination comprising a rotatable printing cylinder, a gear mounted thereon for angular adjustment relative thereto, an operating member mounted on said cylinder for rotation relative thereto, means on said cylinder and operableby said member in response to rotation thereof for disengageably securing said gear to said cylinder, positioning wall means on said cylinder and having a locating opening therein opposite said operating member, and a wrench mounted adjacent said cylinder for rotation and translatory movement against said wall means and through said opening t 'said rotatable member, the reception of said wrench in intoy engagement with said opening being eiective to locate saidcylinder'in a A stationary position withA said operatingmember aligned with said wrench, said wrench and said operatingY member having complementary iriterengageable `formations thereon for transmitting torque 'between said wrench and said operating member.

4. In a registration adjusting mechanism for a printing machine, the combination comprisingarotatable printing cylinder, a gear mounted thereon for angular adjustment l relative thereto, 'a screw member mounted on said cylinder for rotation relative thereto, Vmeans on said cylinder and operable by said member in respose to rotation thereof for disengageably clamping said gear to 4said-cylinder, a positioning plate secured to saidicylinder .and `.having a locating opening therein opposite said rotatable screw member, a wrench mounted forrotationland 4translatory movement against said plate 4andthrough said opening.

into engagement with said rotatable 'screw member, the reception of said wrench in said opening `beingetfective to locate said cylinder in a'stationary position `with said screw member 4aligned with said wrench, said wrench and the relative angular positions thereof, a. rod secured to, .said clamping plate' and extending longitudinally through` 'said cylinder, said rod'having a threaded end portion extending outwardlybeyond the opposite end-ofsaidvcylmder, a nut'screwed onto threaded endportionv for ten- 4 sioning said rod and thereby clamping said second geaigf.r "a positioning plate secured to said opposite end of said i' cylinder and having a locating opening therein positioned opposite sidfnut s:wrench` movable against said positioning plate and through said' opening into engagement with said nut,isaid-wr`ench and said nut having complementary `formations adapted to interlock for transmitting torquebetween-said' wrench and said nut, ashaft supporting saidwrencli 'and 'having handle means thereon,

' means supporting;saidshaft for rotation andsliding move- -ment toward and .away'from-said positioning plate, and i spring meansl biasing'saidshaft away from said positionins "platen l inging/ denomination comprising ,s mastercylindenan offset cylinder engageable with master cylindenyan impression cylinder engageable with ,otfset' cylinder, v a-iirst gear secured to one end l:oi-said odset cylinder, asecond gear meshing" with said said rotatable member having complementary interengageable-formations thereon for transmitting torque be'- tween said wrench and said rotatable member, and spring Y" means biasing said wrench away from said'plate.

irstf-gearjand secured lto lsaid master cylinder, a third gear. :mounted jon saidfoset cylinder-for angular adjust- 'ment' relative'ito'said offset cylinder, a fourth gear mesh- 5. In 'a printing machine, the lcombination comprising ,i a printing cylinder, a gear mounted on said cylinder for.

angular vadjustmentrelative thereto, a clamping plate engageable with said 'gear for disengageably clamping said plate and extending longitudinally through said cylinder, said rod having la threaded end portion extending outward- A Iy beyond the opposite end of said cylinder, a nut screwed gear to said cylinder, a rod` secured to said clamping ing with said "third gear'andsecured to said impression cylinder, -an operating member mounted on said offset cylinder for rotation relative thereto, means on said otset cylinder and operable by said member in response to rotation thereof for disengageably securing said third gear to said offset cylinder, lpositioning wall means on j saidoset cylinder and having a locating opening therein `positioned opposite-said `operating member, and a onto said threaded end portion and engageable with said l cylinder for tensioning said rod and. thereby clamping said gear, a positioning plate secured to said opposite end of said cylinder and having a locating opening therein positioned opposite saidnut, a wrench movable against said positioning plate and through said opening into en-` gagement with said nut, said wrench and said nut havingcomplementary formations adapted to interlock for transmitting torque between said Wrench and said nut, a shaft l supporting said wrench and having handle means thereon, means supporting said shaft for rotation and translatory rotatable 'wrenchmoun'ted adjacent said offset cylinder for translatory movement against said positioning wall means and through said-opening'linto engagement with said operating member, the reception of said wrench in movement toward and away fromsaid positioning plate, i

tioning plate.

and spring'means biasing said shaft away from said posi- 6. In a printing machine, the combination compris- Y ing a printing cylinder, a rst gear secured to one end of said cylinder, a second gear mounted on said cylinder 1 adjacent said first gear for Vangular adjustment relative to said cylinder, a clamping plate engageable with said second gear for disengageably clamping said second gear against said first gear, indicia on said gears to indicate said opening being ete'ctive to locate said oset cylinder in a stationarylposition. with? said operating `member laligned with said Wrench, said wrench and lsad-t'aperating.

member having' complementary formations adapted to interlock 'for transmittingjtorque'betweensaid wrench andsaid rlll t,vv i