US3792657A

US3792657A - Screen printing machine for cylindrical or conical bodies

Info

Publication number: US3792657A
Application number: US00836865A
Authority: US
Inventors: W Kammann
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-06-26
Filing date: 1969-06-26
Publication date: 1974-02-19
Anticipated expiration: 1991-02-19

Abstract

A screen printing machine for monochrome and polychrome printing of cylindrical and conical bodies. The machine comprises a printing stencil secured to a reciprocating slide. A fixed doctor blade is also provided. The stroke of the reciprocating slide is infinitely adjustable. The bodies to be imprinted are rotated about their longitudinal axes in synchronism with the printing stencil. There is further provided an eccentric drive for linearly displacing the printing stencil.

Description

Unite States Patent 11 1 1111 3,792,657

Kammann Feb. 19, 1974 [5 SCREEN PRINTING MACHINE FOR 3,368,481 2 1968 Brockmann 101 40 CYLHNDRICAL 0 CONICAL BODIES 3,436,988 4/1969 Simonton 74/600 X 3,521,298 7/1970 Morel et a1. 101/40 [76] Inventor: Wilfried Kammann, 1 Bustedter Strasse, Suedlengern, Ueber OTHER PUBLICATIONS Buende, Germany Grodzinski, Paul; pp. 147 and 149 of Applying Eccen- [22] Filed: June 26 1969 me Gearing in Machine Design; July, 1954.

[ PP- 8361865 Primary Examiner-Robert E. Pul'frey Assistant Examiner Clifford D. Crowder [30] Foreign Application Priority Data Attorney, Agent, or FzrmJacob L. Kollm June 29, 1968 Germany 6751436 ABSTRACT 52 us. c1 101/38 R, 101/124, 74/31, A Screen Printing machine for monochrome and P y- 74/600 chrome printing of cylindrical and conical bodies. The 511 1111. cu. B411 17/22, B41f 17/28 machine comprises a Priming stonoil secured to a [58] Field of Search 101/38-40, 124, oiprooating Slido- A fixed doctor blade is also p 101 12 74 00 31 30 33 337 35. vided. The stroke of the reciprocating slide is infinitely adjustable. The bodies to be imprinted are rotated 56 References Ci about their longitudinal axes in synchronism with the UNITED STATES PATENTS printing stencil. There is further provided an eccentric drive for linearly displacing the printing stencil. 1,465,702 8/1923 Wile 74/31 UX 2,702,001 2/1955 Gattuso 101/38 X 1 Claim, 7 Drawing Figures PATENTEDFEBI 9:974

SHEET B [If 7 m. mm

INVEN'I'URI Wilfried Kummunn PAIENTE FEB 1' 9 1974 3" 7 92 I 6 5 7 SHEET 5 0r 7 INVEN'I'OR:

Wilfrid Kummunn SCREEN PRINTING MACHINE FOR .CYLINDRICALOR CONICAL BODIES The present invention concerns a screen printing machine having a reciprocatable printing stencil with adjustable stroke and a fixed doctor, for monochrome and polychrome printing of cylindrical or conical bodies which rotate in synchronism with the displacement of the printing stencil about their longitudinal axis and are in rolling engagement along the printing stencil.

It is an object of the invention to provide a screen printing machine avoiding former disadvantages, the machine being provided with a slide supporting a printing stencil, the slide being displaceable in a simple manner and adapted to be readily and accurately adjusted as regards its stroke.

In accordance with the invention a screen printing machine of the type referred to above is characterised by the feature that the slide carrying the printing stencil .is linearly and continuously adjustable in the length of its stroke.

In a preferred embodiment the eccentric drive of a driving device for the screen printing machine is provided with a driving disc continuously rotatable in a horizontal plane and has a radially adjustable body non-movably connected to the slide mounted thereon.

There is a push-rod arranged in a horizontal plane, which is mounted on the adjusting body and is connected non-movably with a slit rotatably mounted on the slide relative to the printing stencil displacement.

An eccentric drive is provided, with a cross loop crank drive connecting the slide carrying the printing stencil to the driving disc; this drive is provided with a guide on the slide carrying the printing stencil and extending at right angles to the movement direction of the slide, which guide by means of a connecting member such as a gate block, pin, bush or the like is connected with the driving disc.

In a further preferred embodiment the slide carrying the printing stencil is formed of two slides linearly displaceable with respect to one another, a gear wheel for the printing stencil displacement being connected to one of the two slides. The gear wheel engages in a racked bar rigidly connected to the machine stand and meshes with a racked bar displacing the printing stencil, whereby the stroke of the slide carrying the printing stencil can be varied in a ratio of 2 1 relative to the stroke of the eccentric drive.

To drive the driving disc, it is connected via an angle drive, preferably a bevel gear drive, to a driving shaft of the driving device for the screen printing machine, and the adjustment of the stroke of the printing stencil is effected by means of an adjusting device connected via angle drives to the threaded spindle; the adjusting device may be provided with a hand wheel for manual actuation which may be connected to a stop device locating the threaded spindle and hence the adjusting body in a position required.

A screen printing machine in accordance with the invention as described above is provided with printing stencil slide of simple structure, driven in a reliable manner and accurately and rapidly adjustable to the size of stroke; this slide is linearly reciprocated by means of an eccentric drive (push-rod or push-crank) and continuously adjusted in the region of the eccentric drive with regard to stroke length. The construction for driving the screen slide is simple and economical to produce. Furthermore the adjustment of the printing stencil stroke is effected by an easy and accurate manipulation.

The adjustment of the size of stroke may be effected with the machine in operation, thus making it unnecessary to shut down the screen printing machine. The ad justing device also has an automatic lock, so that accidental stroke variations during printing are impossible.

The invention will be described further with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a screen printing machine for monochrome and polychrome printing of cylindrical or conical bodies, provided with a slide with printing stencil displaceable linearly at right angles to the axis of rotation of the body to be printed;

FIG. 2 is a cross-section through the same slide with printing stencil;

FIG. 3 is a longitudinal section through the same slide with a gear wheel connected with the slide and displaceable via a driving disc and push-rod;

FIG. 4 is a plan view of the same slide with eccentric drive, partly in section;

FIG. 5 is a longitudinal section through a driving and adjusting device for moving the driving disc and for adjusting the slide stroke;

FIG. 6 is a plan view of the linearly displaceable slide of the screen printing machine, partly in section, show ing an eccentric drive for the slide movement formed as a cross loop crank drive;

FIG. 7 is a longitudinal section through the same slide, provided with a gear wheel which is connected to the driving disc via the crank drive.

A screen printing machine for monochrome and polychrome printing of cylindrical and/or conical bodies 10, has a machine stand 1 l which is provided with a feeding and removal device 14, such as a conveyor belt, fitted with a holding device 12 and adjusting devices feeding the bodies 10 to be printed to a conveying device executing a circular movement path. The said feeding device rotates in a horizontal plane at right angles to the transporting device 13.. The latter 13 takes over the bodies 10 to be printed, conducts them aligned in the necessary starting position, to theprinting position, and returns them after printing to the feeding and removal device 14.

Above the transporting device 13 there is a slide 15 which is linearly displaceable parallel to the plane of the feeding and removal device 15,. which slide is reciprocatingly displaced along parallel extending guides 16, the degree of movement being adjustable.

A printing stencil 17 is rigidly mounted on this slide 15 and executes a reciprocating movement with the slide 15 below a fixed ductor blade 18; it is moved by means of the transporting device in the region of the printing position.

The displacement movement of the slide 15 and hence of the printing stencil 17 is effected by means of an eccentric drive 19 connected to the driving device of the screen printing machine the stroke thereof being adjustable.

This eccentric drive 10 is provided with a driving disc 20 continuously rotating in a horizontal plane, in which there is a radially adjustable adjusting member 21 fixed to the driving disc 20 acting as eccentric. This adjusting member 21 is operationally connected with a push-rod 22 in that the latter has a bearing lug 23 rotatably engaging a pin 21a of the adjusting member 21.

The other end of the push-rod 22 is rigidly connected to a pivot 24 of a gear wheel 25 which in turn is in rolling engagement along a fixed rack 26 and moves a displaceable rack 27.

The slide comprises two relatively displaceable slides, a main slide 28 rotatably receiving the gear wheel and a printing stencil slide 29 executing a displacement movement of twice the extent of slide 28. Both

slides

28,29 are mounted displaceable on guides 16. The gear wheel 25 is rotatably mounted in the main slide 28 by means of roller bearings 30 and the pushrod 22, with a bearing head 32 provided with roller bearings 31 engages the pivot 24 of the gear wheel 25, so that between gear wheel 25 and push-rod 22 there is moving a rotating engagement. The fixed rack 26 is secured by screws rigidly to a bracket 33 and on displacement of the main slide 28 the gear wheel 25 mounted therein is in rolling engagement over the fixed rack 26. The displaceable rack 27 which also meshes with the gear wheel 25 is secured to the printing stencil slide 29 and on displacement of the main slide 28 with gear wheel 25 is displaced by the push-rod 22; on account of the rolling engagement of the gear wheel 25 of the displaceable rack 27 this movement is twice the extent of the displacement of the main slide 28. The eccentric mounting of the adjusting member 21 in the driving disc 20 imparts a reciprocating displacing movement of the push-rod 22 being a rotary movement of the driving disc 20, which produces a linear reciprocating movement of the printing stencil slide 29.

The rotary movement of the disc 20 is effected via an angle drive 34 which is connected via a gear wheel 35 to the driving shaft, not shown, of the screen printing machine driving device. On the underside of the driving disc 20 a hollow shaft 36 is mounted which at its free end is provided with a bevel gear 37; this bevel gear 37 engages in a second bevel gear 39 mounted on a shaft 38 rotatably mounted in the machine stand 11 at an angle thereto, which bevel gear is rigidly connected to the gear wheel 35.

The rotary movement of the driving shaft of the driving device rotates the

bevel gears

39,37, which via the hollow shaft 36 drive the driving disc 20 continuously in a horizontal plane, so that the two

slides

28,29 are displaced via the eccentric drive 19 and the body 10 to be printed is in rolling engagement along the reciprocating slide 29 with the printing stencil 17.

The hollow shaft 36 extends vertically and is rotatably mounted in a bearing 41 provided with roller bearings or the like; the shaft 38 is at right angles to the hollow shaft 36 in a horizontal plane, and its two ends are mounted in

roller bearings

42,43 on the machine stand 11.

The adjusting member 21 is displaceably located in a radial groove 44 extending from the pivot of the driving disc 20, and is traversed by a threaded spindle 45 extending along the groove 44, which spindle is positively connected with the adjusting member 21.

The adjusting member 21 is displaced by rotating the screw spindle 45 which is connected to an adjusting device 48 by means of an

angle drive

46, 47 such as a bevel gearing. A bevel gear 49 fixed to the screw spindle 45 meshes with a second bevel gear 51 fixed to a shaft passing through the hollow shaft 36. On the end of shaft 50 projecting from the hollow shaft 36 a further bevel gear 52 is provided which meshes with a bevel gear 53; this bevel gear 53 is mounted on a hollow shaft 54 about shaft 38. The

pairs

49, 51 and 52, 53 of bevel gears with shaft 50 and the hollow shaft 54 each form an

angle drive

46, 47 which are mutually offset relative one another by On the free end of the hollow shaft 54 there is a gear wheel 55 movably connected thereto which detachably engages its teeth 56 in a stop device 57. This stop device 57, which has a hearing 58 spaced from the shaft 38, receives a pin 59 of the adjusting device. This pin 59 has a hand wheel 60 on the end outside the machine stand 11, and is provided on the free end located Within the machine stand with a gear wheel 61. Between the bearing 58 and machine stand wall 62 there is a clearance provided including a compression spring 63 which retains the adjusting device 48 under spring pressure, the gear wheel 61 in the normal position being out of engagement with the gear wheel 55. The pin 59 provided on the hand wheel 60, and the gear wheel 61 may be displaced axially by a certain amount to give positive connection between the two

gear wheels

61, 55. To do so it is necessary for the hand wheel 60 whilst overcoming the spring pressure, to be drawn axially outwards with the stop device 57, so that owing to the change of position of the gear wheel 61 it meshes with the gear wheel 55 mounted to rotate about the shaft 38. ln this position the stop device 57 has been disengaged from the teeth 56 of the gear wheel 55 and by manually turning the hand wheel 50 the adjustment of the adjusting member 21 for adjusting the stroke may be displaced on the driving disc 20. When the hand wheel 60 is turned, then the

meshing gear wheels

61, 55 rotate the hollow shaft 54 via pin 59 which also rotates the bevel gears 53, 52 and the bevel gears 51, 49. The bevel gear 49 connected to the screw spindle 45 now transmits its rotary movement thereto, so that the adjusting member 21 is displaced on the screw spindle 45 in accordance with the direction of rotation. This displacement of the adjusting member 21 varies the distance thereof relative to the axis of rotation of the driving disc 20 and adjusts the displacement movement of the push rod 22. The magnitude of the rod movement determines the magnitude of the reciprocating movement of the printing stencil 17.

When the hand wheel 60 is released, spring 63 forces the gear wheel 61 out of engagement with the gear wheel 55 and the meshing device of both

gear wheels

55, 61 is interrupted; at the same time the stop device 57 engages its teeth 56 in the teeth 56 of the gear wheel 55 and prevents the hollow shaft 54 from rotating whereby the position of the adjusting member 21 is fixed and prevented from accidental movement; the adjustment of the size of stroke may be carried out with one manipulation by actuating the hand wheel.

The adjustment of the size of stroke of the printing stencil 17 is determined by the length of the screw spindle 45 and may be infinitely varied over a predetermined distance, so that the outer surface to be printed may be adjusted to an optional printing surface. The eccentric drive 19 provides a linear reciprocating movement of the printing stencil 17, and also an adjustment of the stroke of the printing stencil 17 so that the various bodies to be printed may be accurately adjusted to the printing surface size in accordance with their outer surface formation.

A further embodiment of a drive for the slide i5 is shown in H68. 6 and I of the drawings. The machine is provided with a cross head drive 65 connecting the slide carrying the printing stencil 17 with the driving disc 20, which drive causes the slide 15 to carry out a uniform linear reciprocating movement.

The basic structure of the slide 15 corresponds to the embodiment shown in FlGS. l to 4, except that the push rod 22 for the main slide 28 displacement is omit ted.

This cross head drive 65 forming an eccentric drive for the main slide 26 carrying the gear wheel 25, is provided with a guide extending at right angles to the direction of the slide movement, which guide is connected to the driving disc 20 rotating in a horizontal plane by means of a coupling member 67.

The guide 66 is provided at one end of the slide, it is arranged at right angles to the direction of movement of the slide and fixed thereto. The guide 66 extends to the underside of the main slide 28 and has a displacing groove 66a. extending substantially over the whole width of the slide in which the coupling member 67 is in rolling and/or sliding engagement.

It is preferred to form the guide 66 as a rail of U- shaped cross-section secured to the underside of the slide and form the coupling member 67 as a gate block, pin or bush. The coupling member 67 has a rotatable connection with the pin 21a of the driving disc 21.

During rotary movement of the driving disc 20 driven by the drive of the screen printing machine, the disc causes the slide 115 to carry out a reciprocating linear movement via the cross head crank drive 65 and the slide 29 carrying the printing stencil 17 has imparted thereto a displacement movement by the gear wheel 25 in rolling engagement over the fixed rack 26 which is twice that of the main slide 26 moved by the crank drive 65.

The coupling member 67 located in the guide 66 to form a connection between main slide 28 and driving disc 20, executes a circular movement path due to the rotation of the driving disc, and at the same time is reciprocated linearly in the guide 66, so that the slide 28, when the driving disc is rotated, is reciprocated linearly and thus also imparts a linear displacement to the printing stencil slide 29 via the gear wheel 25 and the

racks

26, 27, so that the stroke of the printing stencil slide 29 is in a ratio of2 l to the stroke of the cross head drive 65.

The screen slide drive (eccentric drive 19 and cross head crank drive 65) moves the printing stencil 117 over its whole displacement path uniformly in both directions, since due to the

drives

19, 65 favourable angle conditions between the gear wheel 25 and the driving disc 20 have been provided, the slight angular displacements occuring in the end regions (reversing points) of the slide movement, so that accurate printing of the articles is ensured.

The printing stencil 17 has a uniform speed over the whole path of its displacement and the articles to be printed are rotated synchronously with the displace ment of the printing stencil 17. The transmission drive from driving disc 20 to slide 15 and the arrangement of the driving disc 20 in a horizontal plane is a cheap method of construction; furthermore these drive arrangements provide small drive components (driving disc 20, push rod 22) and relatively small distances between driving disc 20 and gear wheel 25.

it is within the scope of the invention to effect the transmission of the driving movement from the driving device to the driving disc by gears of alternative design; it is also possible to connect the adjusting device to the adjusting member by means of alternative gearings.

it is furthermore within the scope of the invention to arrange the transporting device with holding devices for the articles to be printed so as to be adjustable about a pivot, so that the bodies with their optional outer surfaces may be adjusted to the printing stencil located in a horizontal plane.

The driving movement for the slide carrying the printing stencil, the transporting device receiving the body to be printed and an adjusting device hold the body to be printed in a predetermined position in the printing region and being in rolling engagement along the printing stencil are controlled so as to act in synchronism; all parts of the screen printing machine may be driven by one driving device.

I claim:

1. A screen printing machine for monochrome and polychrome printing of cylindrical and conical bodies, comprising a frame, a printing stencil mounted on said frame, a fixed doctor blade, means for reciprocating said printing stencil which includes a slide means, said slide means including a main slide and a printing stencil slide, means for effecting synchronous rotation of said bodies about their longitudinal axes with the reciprocation of the printing stencil, drive means for linearly displacing said slide means, said drive means comprising a driving disc, a stationary rack mounted on said frame, a gear wheel mounted in said main slide and meshing with said stationary rack, a movable rack mounted on said printing stencil slide and meshing with said gear wheel, said movable rack being parallel to said stationary rack and on the opposite side of said gear wheel from said stationary rack, a U-shaped crosshead guide mounted on said main slide at one end thereof, a coupling member mounted on said driving disc and in rolling engagement with said crosshead guide for transferring rotary motion of said driving disc to reciprocating motion of said main slide, said printing stencil slide reciprocating in a 2:1 ratio relative to the stroke of said main slide due to the rotation of said gear wheel be tween said stationary rack and said movable rack, an adjusting device for adjusting the position of said coupling member radially of said driving disc to thereby vary the stroke of said main slide, said adjusting device comprising a screw spindle rotatably mounted in said driving disc and threadably engaging said coupling member whereby rotation of said screw spindle adjusts the position of said coupling member, a bevel gear system for effecting rotation of said screw spindle, said bevel gear system connected between said screw spindle and a first shaft parallel to said driving disc, said first shaft having a gear mounted thereon which is selectively engageable with a second gear mounted on a second shaft parallel to said first shaft, said second gear being normally out of engagement with said first gear, said second shaft being spring biased in a direction such as to force said second gear out of engagement with said first gear and having a hand wheel thereon, whereby axial movement of said hand wheel moves said second gear against the bias of said spring into engagement with said first gear and rotation of said handwheel effects rotation of said screw spindle through said bevel gear system to thereby adjust the position of said coupling member and vary the stroke of said main slide.

=t l= =l= =l

Claims

1. A screen printing machine for monochrome and polychrome printing of cylindrical and conical bodies, comprising a frame, a printing stencil mounted on said frame, a fixed doctor blade, means for reciprocating said printing stencil which includes a slide means, said slide means including a main slide and a printing stencil slide, means for effecting synchronous rotation of said bodies about their longitudinal axes with the reciprocation of the printing stencil, drive means for linearly displacing said slide means, said drive means comprising a driving disc, a stationary rack mounted on said frame, a gear wheel mounted in said main slide and meshing with said stationary rack, a movable rack mounted on said printing stencil slide and meshing with said gear wheel, said movable rack Being parallel to said stationary rack and on the opposite side of said gear wheel from said stationary rack, a U-shaped crosshead guide mounted on said main slide at one end thereof, a coupling member mounted on said driving disc and in rolling engagement with said crosshead guide for transferring rotary motion of said driving disc to reciprocating motion of said main slide, said printing stencil slide reciprocating in a 2:1 ratio relative to the stroke of said main slide due to the rotation of said gear wheel between said stationary rack and said movable rack, an adjusting device for adjusting the position of said coupling member radially of said driving disc to thereby vary the stroke of said main slide, said adjusting device comprising a screw spindle rotatably mounted in said driving disc and threadably engaging said coupling member whereby rotation of said screw spindle adjusts the position of said coupling member, a bevel gear system for effecting rotation of said screw spindle, said bevel gear system connected between said screw spindle and a first shaft parallel to said driving disc, said first shaft having a gear mounted thereon which is selectively engageable with a second gear mounted on a second shaft parallel to said first shaft, said second gear being normally out of engagement with said first gear, said second shaft being spring biased in a direction such as to force said second gear out of engagement with said first gear and having a hand wheel thereon, whereby axial movement of said hand wheel moves said second gear against the bias of said spring into engagement with said first gear and rotation of said handwheel effects rotation of said screw spindle through said bevel gear system to thereby adjust the position of said coupling member and vary the stroke of said main slide.