US2809581A - Drive system for a web printing machine - Google Patents

Description

Oct. 15, 1957 E. w. CLEM 2,809,581

DRIVE SYSTEM FOR A WEB PRINTING MACHINE Filed June 25, 1954 5 Sheets-Sheet 1 INVENTOR.

Oct. 15, 1957 E. w. CLEM DRIVE SYSTEM FOR A. WEB PRINTING momma:

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DRIVE SYSTEM FOR A WEB PRINTING MACHINE Filed June 25, 1954 '5 Sheets-Sheet 4 Oct. 15, 1957 E. w. CLEM DRIVE SYSTEM FOR A WEB PRINTING MACHINE 5 Sheets-Sheet 5 Filed June 25, 1954 INVENTOR.

E's/eff M [/6772 United States Patent 2,809,581 DRIVE SYSTEM FOR A WEB PRINTING MACHINE Everett W. Clem, Shrewsbury, Mass., assignor to Rice Barton Corporation, Worcester, Mass., a corporation of Massachusetts Application June 25, 1954, Serial No. 439,239 7 Claims. (Cl. 101-178) This invention relates to a printing machine of the type embodying an impression cylinder, of relatively large diameter, to which rotary motion is imparted by surface contact with a series of engraved printing rollers of smaller diameter, which rollers are arranged around the periphery of the impression cylinder. The material to be printed passes, in the form of a continuous web, around the periphery of the impression cylinder and engages successively the surfaces of the printing rollers. In such a manner the printed pattern is applied to this material. In particular, this invention relates to the drive system for the printing rollers of such a machine.

On conventional machines of the above-mentioned type, where a plurality of designs or a multi-colored pattern is desired, it is customary to employ a separate engrayed printing roller for each design or color imprinted on the material. Needless to say, in such a case, it is also necessary to provide means for accurately registering one design with relation to the other or others so that each will be properly spaced (or superimposed if desired) with respect to the other. Such a registering means is always connected to the driving mechanism for the engraved rollers as will appear below.

The driving mechanism for a conventional printing machine of the above-mentioned type generally consists of a large driven spur gear which is mounted for free rotation on one end of the central shaft of the large cylinder of the machine; thus, since the impression cylinder is not operatively connected to the large gear, the rotation of the former is only an indirect result of the turning of the latter, as will hereinafter appear. A plurality of smaller spur gears are mounted in meshing relation with the large spur gear such that each smaller spur gear is coaxial with the shaft of its associated engraved roller. The engraved rollers are arranged around the periphery of the freely rotatable cylinder such that the surfaces of the rollers will bear against the surface of the cylinder so as to drive the latter. Each of the smaller spur gears fits over a worm gear sleeve, or quill, which is keyed to the shaft of the engraved roller. A worm is mounted on the face of each smaller spur gear so as to properly mesh with the worm gear portion of the worm gear sleeve. Thus, the smaller spur gears are not connected directly to the shafts of the engraved rollers, but indirectly through the worm and worm gear combination. By turning manually the worm which is mounted on the face of the smaller spur gear, the angular relationship between the shaft of the engraved roller and its associated smaller spur gear can be varied. This worm type of adjustment is illustrated in Figs. 2 and 3 of United States Patent No. 2,615,770, issued to I. W. Vedder on October 1, 1935. In such a fashion the angular relationship between the various engraved rollers themselves may be adjusted to provide further registry of the patterns relative to one another.

The above described adjustment involves several serious difficulties. First of all, when the printing machine is in operation, the smaller spur gears are constantly ro- 2,809,581 Patented Oct. 15, 1957 ICC tating and, hence, the adjustable Worms are rotating with the spur gears. If the operator wishes to make an adjustment, he must either slow the machine down or stop it entirely so that he can turn the worm of the misaligned roller to its proper position. Naturally, it is diflicult to make an adjustment on a part in motion. Moreover, there is always a danger that the wrench with which the adjustment must be made might strike against some stationary object during the period of time that the operator is turning the worm; this condition might cause the wrench to break or fly off with possible injury to the operator. On the other hand, whether the machine is stopped or merely slowed down, there is a consequent loss in production, which, of course, involves expense.

Another serious disadvantage in the above-described system pertains to the stopping of the machine itself. When this machine is shut down for any reason, at the moment that the forward motion of the machine ceases, the impression cylinder, because of its large mass and high moment of rotational inertia, will move forward and then back, thus causing a certain amount of roll-back or back-lash of the printing rollers. This back-lash will cause the doctor blades, which scrape off the excess ink from the rollers, to dig into the engraved surfaces of the rollers, thereby effecting considerable damage to the rollers.

It is a principal object of this invention to provide a drive system in which each engraved roller is driven by an adjustable driving member whose position may be varied while the machine is running at its normal operating speed so as to permit angular adjustment of the rollers relative to one another.

Another object of this invention is to provide a drive system of the type referred to above wherein the adjustment is applied to an element which is normally stationary even when the machine is running at full speed.

Another object of this invention is to provide a drive system of the type referred to above wherein the adjustment may be easily and safely made without involving any danger to the operator.

Another object of this invention is to provide a drive system of the above-mentioned type wherein back-lash of the printing rollers is also eliminated.

Other and further objects and advantageous features of my invention will hereinafter more fully appear in connection with a detailed description of the drawings in which:

Fig. 1 is a front view of a web printing machine embodying my invention.

Fig. 2 is a fragmentary plan view of the printing machine shown in Fig. 1.

Fig. 3 is a fragmentary right side view taken from Fig. 1.

Fig. 4 is a front view on an enlarged scale of the drive mechanism shown in Fig. 1, with some parts in section.

Fig. 5 is a front view of a web'printing machine similar to Fig. l, but using a different gearing arrangement.

Fig. 6 is a fragmentary view on an enlarged scale taken along section line 6-6 of Fig. 5.

'Fig. 7 is a view similar to Fig. 4 showing a modification of my driving mechanism.

Referring to the drawings in detail, Fig. 1 shows a large printing cylinder I mounted for free rotation on a shaft 2 which is journaled at its ends in a pair of vertical frame members 3, only one of which is shown in Fig. 1. A hypoid gear 4 is mounted on the end of shaft 2. A small bevel gear 5, which is keyed to a drive shaft 6, meshes with the hypoid gear so as to drive the latter.

Two other small bevel gears 7 and 8 are arranged in meshing relation with the hypoid gear 4 so as to drive a pair of engraved rollers 9 and 10, respectively, .in a manner later to be described. Although only two such turning any pressure screw 13, the pressure of splines 34.

engraved rollers are shown here, for the sake of convenience, it is understood that three, four, five or more engraved rollers might be used depending upon the requirements of the particular design or pattern to be imprinted on the web. 7 I l Each engraved roller may be urged towards the cylinder 1 by a pair of slidable bearing blocks 11 one of which is mounted at each end of a roller. In Fig. 1 only one such block is shown as associated with each roller since the rollers themselves are in side elevation. The bearing blocks 11 are slidably mounted in supports 12 which are attached to the frame members 3. The blocks 11 may be moved towards and away from cylinder 1 along suports 12 by means of pressure screws 13 which are threaded at their ends into flanges 14 of supports 12. Thus by its associated roller against the drum may be varied as desired.

The drive mechanism foreach engraved roller will be described with particular reference to roller 9, but it should be understood that this description applies also to the engraved roller 19 or to any other engraved roller used in the same printing operation. Bevel gear 7 is attached to shaft 15 which passes into housing 15 which in turn is secured to frame 3. Within housing 16, shaft 15 is coupled to shaft 17 by means of a splined arrangetnent which will be described later. Shaft 17 extends into the interior of drive unit '18.

Referring now toFig. 4 which shows the drive unit er se, and to Figs. 2 and 3 which show the relationship between the drive unit and the engraved roller the right-hand end of shaft 17 (as it appears in Fig. 4) is formed into a worm 19 which meshes with a worm 2t Worm gear 20 is keyed to a shaft 21 which is journaled into the opposite sides of the casing 22 of the drive unit 18. Shaft 21 (see now Figs. 2 and 3) is attached to journal 23 of the engraved roller 9 by means of a coupling 24. By sliding the coupling 24 to the left on shaft 21, journal 23 can be disengaged so as to permit removal of roller 9.

For the purposes of making the pressure adjustment of the engraved roller against the drum as described above, journal 23 is provided with a bearing collar 25 which is made integral with journal 23. This bearing collar or bushing fits into a corresponding curved recess 25 in the bearing block 11. Collar 25 and recess 26 prevent the roller 9 from shifting laterally along its axis.

Each of the supports 12 has laterally extending projection 39 containing a rectangular groove 31 into which the base of drive unit 18 fits. Drive unit 18 is slidable along this groove by means of brace 32 so as to permitalignment of shaft 21 and journal 23 at all times.

Shaft 17 is slidable with respect to shaft 15 within the housing 16 by means of cooperating male and female splines (see now Pig. 4). Shaft 17 has a set of male splines 33 which are slidable within a set of female Female splines 34 are located within a hollow recess 35' of an enlarged axial extension 36 of shaft 15. At the right-hand end of extension 36, as it appears in Fig. 4, I have provided a circumferential flange 37 which fits into an annular groove 38 of The flange and groove shaft 15.

For the purposes of making shaft 21 (and hence roller angularly adjustable with respect to shaft 17, I have provided a thrust bearing 38 which is secured to the righthand end of shaft 17 by means of threaded nut 39 and shoulder. 40.. Bearing 38 is rotatable within an annular groove 41 of a cylindrical slide member 42 which bears against the inner cylindrical surface 43.0f the drive unit 13. At the right-hand end of slide member 42 a threaded bolt. 45 is journaled in hole 46 with nut 47 preventing axial movement of bolt'45 with respect to slide member 42. The-right-hand end of bolt 45 projects through a threaded hole'48inend of drive unit 18. -By turning bolt the housing 16. prevent axial displacement of the gear 45 in one direction or the other, shaft 17 may be shifted axially whether the machine is running or not.

Assuming that the machine is operating at its normal speed, shafts 15, 17 and 21, and roller 9 will be rotating continuously and thrust bearing 38 will be turning within annular groove 41. Bolt 45 will be stationary, however, regardless of the speed of the machine. By turning the bolt 45, the shaft 17 may be shifted axially and the phase relationship between shaft 17 and roller 9 will be altered accordingly. The displacement of shaft 17 will be compen-sated for by the splines 33 and 34.

As can be seen from Figs. 1 to 4 I have provided a driving system which will permit relative angular adjustment of the individual engraved rollers while the machine is running at its normal operating speed, thereby eliminating a source of down time. Also, since bolt 45 is stationary even while the machine is running, the adjustment may be made without any danger to the operator.

Again, since the individual rollers are driven by worms and worm gears, as opposed to the conventional spur gears, when the machine is stopped the rollers will be locked in position without any attendant back-lash, which as described above would cause damage to the engraved rollers.

in the conventional prior-art devices, it has been necessary heretofore, when changing from one set of rollers of a certain uniform size to another set of engraved rollers of a different size, to change also the large driven spur gear; by virtue of the worm gear drive which is slidable with block 11, the same drive system may be used regardless of the size of the engraved rollers employed.

, Referring again to Fig. l the central driving gear 4 has been described as a hypoid gear, for the reasons appearing below. As shown in Fig. 1 bearing blocks 11 are slidable along radii of cylinder 1; shafts 17, which are slidable in parallel relation to blocks 11, are not radial with respect to cylinder 1 or shaft 2, however. In order to provide the non-radial relationship shown in Fig. 1, it is necessary to use hypoid gears or spiral bevel gears. For this reason gear 4 has been described as a hypoid gear. Smaller gears 5, 7 and 8 would also be hypoid gears as shown in Fig. l. The invention is not limited to a machine employing hypoid gears or spiral bevel gears: the system shown in Figs. 5 and 6 illustrates my invention in connection with a machine using conventional bevel gears.

In Fig. 5 I have shown a large printing cylinder 1 mounted for free rotation on shaft 2 which is journaled at its ends in a pair of vertical frame members 3, only one of which is shown in this figure. A large bevel gear 4a is mounted on the end of shaft 2. Small bevel gear 5:: which is keyed to drive shaft 6 meshes with gear 4a so as to drive the latter.

A plurality of other small bevel gears in, 7b and 7c are arranged in meshing relation with large bevel gear 4a so as to drive rollers 9a, 9b and 9c respectively in a manner later to be described. Although only three such engraved rollers are shown here for the sake of convenience, it is understood that four, five or more engraved rollers might be used, depending upon the requirements of the particular design to be imprinted on the web. The engraved rollers 9a, 9b and 9c are urged towards the cylinder 1 in the same manner as described in relation to Fig. 1. It should be noted in Fig. 5, as a distinction from Fig. 1, that shafts 15a, 15b and 15c, as well as their extensions, 17:: (not shown), 17.) and 17c, are radial with respect to shaft 2.

The drive unit for each engraved roller is coupled 'to bevel gear 412 in the same manner as described in relation to Fig. 1. For example, referring in particular to roller 95, small bevel gear 712 is attached to shaft which passes into housing 16b, the latter being secured to frame 3. Within housing 16b, shaft 155 is coupled to shaft 17b by means of the splined arrangement shown and described in relation to Fig. 4. Shaft 17b extends into the interior of drive unit 1812 which is identical in all respects to drive unit 18 of Fig. 4 except that it is not coupled to block 11 for sliding movement therewith.

As shown in Fig. 6, support 12 has a laterally extending projection 3017 containing a rectangular groove 31b into which the base of drive unit 1819 fits. Drive unit 18b may be adjusted to difierent positions along groove 31b but it is not slidable therein. The drive unit 18b is secured against sliding movement within groove 3119 by means of a set screw 50 which bears against the side of the unit. The shaft 21 of drive unit 18b is coupled to the journal 23 of roller 9b by means of a standard universal coupling 51 which is attached to shaft 21 at 52 and to journal 23 at 53. The coupling 51 has a universal joint at each end and an intermediate splined fitting so as to permit telescoping of the coupling. With this arrangement drive unit 1812 can be held stationary regardless of the position of slide block 11. The brace 32 shown in Figs. 2 and 3 is not used in the modification shown in Fig. 6. The shaft 21 of Fig. 6 is rotatably adjustable in the same manner as described in relation to Figs. 1 to 4. The arrangement shown in Figs. and 6 has all of the advantages of the one shown in Figs. 1 to 4 although the method of coupling and gearing is slightly different.

Fig. 7, which is a modification of Fig. 4, shows a drive unit 18g through which shaft 17d extends. A series of couplings such as 55 are located at various points along the length of shaft 17d in order to permit removal of individual units. Shaft 17d has a set of male splines 56 which fit into corresponding female splines 57 of quill 53. Quill 58 has a circumferential worm portion 1% which cooperates with worm gear 26 of the drive unit. Worm gear is keyed to shaft 21 which may be coupled to the journal of the roller in the manner shown in Figs. 2 and 3 or in the manner shown in Fig. 6. All of the parts within unit 18g are the same as those shown in Fig. 4 and are similarly numbered. Bolt 45 however is mounted eccentrically with relation to cylindrical slide member 42. Slide member 42 and drive unit 18g are provided with holes 60 and 61 respectively to permit passage of shaft 17d therethrough. Unit 18g is attached to bracket g by means of threaded bolts 62 and 63.

Whereas my invention has been described with particular reference to the embodiments shown herein, other modifications, apart from those shown, may be made within the spirit of my invention.

I claim:

1. In a web printing machine of the type having a relatively large impression cylinder mounted for free rotation on a central shaft and a plurality of smaller printing rollers mounted on individual shafts around the periphery of said cylinder, the sufiaces of said rollers being adapted to engage the surface of said cylinder so as to drive the latter rotatably, the improvement which comprises a worm gear attached to the end of each roller shaft, a worm disposed in meshing relation with each worm gear, a worm shaft coupled to each worm so as to drive said worm, all of said worm shafts being directed convergingly inward towards said central shaft, a common source of rotary power coupled to the inner ends of said worm shaft for driving the latter, and means associated with each worm for permitting movement of said Worm along its axis.

2. In a web printing machine of the type having a large impression cylinder mounted for free rotation on a central shaft, a plurality of smaller printing rollers mounted on individual shafts and arranged around the periphery of said cylinder for surface contact therewith, whereby rotation of said rollers will cause rotation of said cylinder, and means associated with each roller for moving said roller towards and away from said cylinder so as to vary the contact pressure thereby, the improvement which comprises a worm gear attached to the end of each roller shaft, a worm disposed in meshing relation with each shaft, a worm shaft coaxial with each worm extending from said worm inwardly towards said central shaft, a large driven bevel gear mounted for free rotation on one end of said central shaft, a bevel pinion attached to the inner end of each worm shaft so as to mesh with said bevel gear, and means operatively associated with each worm for permitting sliding movement of said worm along its axis.

3. The improvement according to claim 2 in which said bevel gear and bevel pinions have cooperating spiral teeth and wherein said worm shafts are non-radial with respect to said central shaft.

4. In a web printing machine of the type having a large impression cylinder and a plurality of smaller printing rollers arranged around the periphery of said cylinder for surface engagement therewith, the shafts of said rollers being substantially parallel with the central shaft of said cylinder, the improvement which comprises a worm gear attached to the end of each roller shaft so as to drive the same, a Worm disposed in meshing relation with each worm gear, a worm shaft coaxial with each worm and attached thereto, all of said worm shafts extending radially inward towards said central shaft, a spiral bevel gear mounted for free rotation on one end of said central shaft, a source of power for driving said spiral bevel gear, a spiral bevelled pinion attached to the inner endof each worm shaft for engagement with said spiral bevel gear, and means associated with each worm for permitting axial movement of said worm with respect to its pinion, whereby the angular relationships between the various roller shafts may be varied.

5. The improvement according to claim 4 in which said means for permitting axial movement of each worm includes an intermediate splined coupling mounted on each worm shaft intermediate the ends thereof, whereby the outer portion of each worm shaft may be moved axially relative to the inner portion thereof, and a nonrotatable slide member connected to the outer end of each worm shaft by means of a thrust bearing.

6. The improvement according to claim 4 in which each worm comprises a quill splined to its associated worrn shaft for sliding engagement therewith, and in which a non-rotatable slide member, movable in a direction along each worm shaft, is connected to each quill through cooperating and interfitting bearing surfaces on said slide member and said quill, whereby each quill is rotatable and axially immovable with respect to its slide member.

7. In a web printing machine of the type having a large impression cylinder rotatably mounted on a central shaft, and a plurality of smaller printing rollers mounted on individual shafts and arranged. around the periphery of said cylinder, an anti-backlash drive comprising a worm gear connected to the end of each roller shaft, a worm disposed in meshing relation with each worm, a worm shaft operatively connected to each worm, all of said worm shafts extending inwardly from said worms towards said central shaft, a common source of power connected to the inner ends of said worm shafts for common rotation thereof, and means for adjusting the position of each worm along its axis.

References Cited in the file of this patent UNITED STATES PATENTS 2,163,035 Grupe June 20, 1939 2,183,045 Presby Dec. 12, 1939 2,425,914 Blackley et a1. Aug. 19, 1947 2,539,068 Funk Jan. 23, 1951 2,560,774 Luttenauer July 17, 1951

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