Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F15/00—Screen printers
  • B41F15/08—Machines
  • B41F15/0804—Machines for printing sheets
  • B41F15/0809—Machines for printing sheets with cylindrical or belt-like screens
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F15/00—Screen printers
  • B41F15/08—Machines
  • B41F15/0831—Machines for printing webs
  • B41F15/0836—Machines for printing webs by means of cylindrical screens or screens in the form of endless belts
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F15/00—Screen printers
  • B41F15/14—Details
  • B41F15/34—Screens, Frames; Holders therefor
  • B41F15/38—Screens, Frames; Holders therefor curved

Definitions

• the invention relates to a screen printing machine and screen cylinder according to the preamble of claim 1, 2, 7 or 12.
• EP 1 090 752 A1 describes a screen cylinder for a screen printing machine.
• This screen cylinder is essentially constructed from two support rings, which form the axial ends of the screen cylinder, and a screen in the form of a thin fabric jacket, the edges of which are attached to the support rings.
• the support rings are rotatably mounted on frames of the screen printing machine.
• the screen cylinder must be removed and installed from time to time when changing jobs or to replace a worn screen.
• the support rings of the screen cylinder each have a ring gear or an equivalent coupling device which engages with a drive head of a transmission in order to drive the rotary movement of the screen cylinder. This intervention must be canceled when removing the screen cylinder and restored when reinstalling it. This makes installation and removal time-consuming.
• the presence of the ring gear increases the weight of the support rings and complicates their handling during installation and removal.
• the AT 382 821 B shows a circular sieve which is fastened in a bearing by means of a bayonet lock.
• the invention has for its object to provide a screen printing machine and a screen cylinder.
• the object is achieved by the features of claim 1, 2, 7 or 12.
• the support ring of conventional screen cylinders is divided into two parts, on the one hand into a rotatably drivable ring, which is regarded as part of the bearing arrangement of the screen cylinder and which no longer has to be removed when the screen cylinder is replaced, and on the other hand a head piece of the screen cylinder, which is attached to claws of said ring is detachably mountable and only has the function of clamping the sieve in the desired cylindrical shape.
• the claws of each ring can only be placed on one half of its circumference. A head piece can thus be introduced into or removed from its position held on the ring in a movement transverse to the axis of the screen cylinder, via the half of the circumference of the ring free of claws.
• the rings of the two bearing arrangements each carry at least two claws, at least one of which from a position in which it lies together with the at least one other claw on one half of the circumference of the ring, around the axis of the screen cylinder in one position is rotatable, in which not all of the claws lie on one half of the circumference of the ring.
• the position in which the rotatable claw is fixed is preferably diametrically opposite the other claw with respect to the axis of the screen cylinder. More generally, it can be said that the center of gravity of the rotatable first claw is diametrically opposite to that of the at least one other, non-rotatable claw.
• the ring has only a single claw or a plurality of claws, which, however, are immovable relative to one another. In this case, in order to achieve a secure hold of the head piece on the ring, it is necessary that two lateral edges of the claws form an angle of 180 ° with respect to the axis.
• a secure hold of the head piece on the ring can be achieved in particular in that the claw or claws each have an inner surface provided for contact with the head piece, which lies on a cone centered around the axis of the screen cylinder, the The apex of the cone lies on that side of the bearing arrangement which has the claws and which faces away from the respective other bearing arrangement.
• Spring elements can be provided on the claws of the ring of at least one bearing arrangement and exert an axial force oriented away from the other bearing arrangement on a head piece mounted on the claws. These spring elements can serve different purposes.
• the screen printing machine can be designed such that the spring elements keep a gap between the head piece and the inner surfaces of the holding claws open during their operation.
• the axial tension under which the sieve is located is determined by the force of the spring elements and can be adjusted within certain limits by adjusting the axial position of the rings.
• the advantage of this design is that if an axial blow briefly drives the head pieces apart or a force acting radially on the sieve increases its tension in the axial direction, the springs give way and thus limit the sieve tension and prevent the sieve from tearing.
• the inner surfaces of the claws touch the flange during operation of the screen printing machine, for example in order to pinch it and hold it in place.
• the spring elements can serve when Removal of the screen cylinder to loosen its head pieces from the holding claws. This may be necessary in particular if the head piece sticks to the claws due to paint residues accumulated during operation.
• a head piece for a sieve cylinder has a cylindrical support section for fastening a sieve and a flange which is connected to the support section and projects in the radial direction and on which the claws can engage.
• its flange In order to be able to transmit a rotary drive force from the ring to the head piece, its flange preferably has a non-circular radial cross-section, in particular in the form of two successive sections in the circumferential direction with different radial widths.
• the extent of these sections in the circumferential direction is preferably dimensioned such that radially oriented surfaces, which separate the sections of different radial widths of the flange from one another, each abut a lateral edge of a claw.
• Fig. 1 is a perspective view of a screen cylinder and its
• FIG. 2 shows an axial section through the bearing arrangements of FIG. 1;
• FIG. 3 shows a head region of a screen cylinder according to the invention
• FIG. 4 and 5 is a perspective view of a bearing arrangement with or without held screen cylinder
• FIG. 6 shows an axial section analogous to FIG. 2 through a second embodiment of a screen printing machine according to the invention
• Fig. 7 is a view of a bearing arrangement according to the second embodiment.
• Fig. 1 shows a partial perspective view of a screen printing machine according to the invention.
• a screen cylinder 01 held by two bearing arrangements 02; 03, which are each mounted on frames 04 of the screen printing machine that are only partially shown.
• a doctor blade which is also connected to the frames 04 and is mounted in a stationary manner within the screen cylinder 01, is not shown.
• Each bearing arrangement 02; 03 comprises a hollow cylindrical shaft 06 firmly connected to the respective frame 04, on which a ring 07 via a bearing 08, e.g. B. a needle bearing 08 is rotatably mounted.
• An outer ring gear 09 of each ring 07 is surrounded on a large part of its circumference by a sleeve which is firmly connected to the neighboring frame 04.
• a window 10 of the sleeve shown in Fig. 1 allows the engagement of a gear 11 in the ring gear 09 of the bearing arrangements 02, 03.
• the gears 11 on both sides of the screen printing machine can be driven by a drive motor at the same speeds via a gear, not shown.
• the ring 07 is made up of two concentric partial rings 12; 13, an inner partial ring 12, which carries the ring gear 09 and a first claw 13, which will be explained in more detail later, and an outer partial ring 14, which can be rotated around the inner partial ring 12 and carries a second claw 16.
• these two claws 13; 16 shown diametrically opposite each other.
• the outer part ring 14 is rotationally fixed with respect to the inner part ring 12 by a spring capsule 17 which is embedded in the inner part ring 12 and presses a ball 18 into a recess on the inside of the outer part ring 14 facing the inner part ring 12.
• the two claws 13; 16 each have a stem section 19 extending parallel to the axis of the screen cylinder 01; 21 and a head portion 22 or 23 extending radially from the free end of the stem portion 19 or 21 to the axis of the screen cylinder 01.
• the stem section 19 of the first claw 13 extends in a semicircle over half the circumference of the ring 07.
• the head section 22 of the first claw 13 is, on the other hand, shorter.
• the side section 19 and head section 22 are flush on a side 24 of the first claw 13 facing the viewer in FIG. 4, on the opposite side 26 the head section 22 ends approximately 30 ° earlier than the section 19.
• the rotatable second claw 16 in turn extends over approximately 30 ° of the circumference of the ring. It can be rotated from the position shown in FIG. 4 into a position in which its head section 23 touches the side 26 of the head section 22, so that both claws 13, 16 together extend over exactly half the circumference of the ring 07.
• the screen cylinder 01 comprises two head pieces 27, each for mounting on the bearing arrangements 02; 03 are provided, as well as a sieve 28 cylindrically spanned by the head pieces 27.
• this head piece 27 is constructed in one piece from a cylindrical support section 29, the outer surface of which is provided, around which the sieve 28 is attached in a manner known per se to fasten, and a radially projecting flange 31, which are connected to one another by a transition section 32, each with a smaller outside diameter than that of the support section 29 or the flange 31.
• FIG. 3 shows a perspective partial view of the screen cylinder 01 with a head piece 27.
• the flange 31 of the head piece 27 has two sections 34 which are offset in the circumferential direction from one another by radially oriented surfaces 33; 36 with different radii.
• Each section 34; 36 extends here over half the circumference of the flange 31.
• the radius of the section 34 with a smaller radius corresponds to the inner radius of the handle section 19, that of the section 36 with a larger radius to the outer radius of the handle section 19 or, which is preferably the same except for a slight play is, the inner radius of the stem portion 21.
• the flange 31 thus formed can be inserted into the bearing arrangement 02 or 03 in a movement transverse to the axis of the screen cylinder 01 ,
• the radially oriented surfaces 33 come into contact with the sides of the stem section 21.
• the head piece 27, as shown in FIG. 5, is fixed to the bearing arrangement 03.
• the radially oriented surfaces 33 of the flange 31 are each in contact with the edges of the stem section 19 of the first claw 13, so that a rotation of the ring 07 is transmitted exactly to the screen cylinder 01.
• the bearing arrangement 03 is provided with three linear actuators 37 in the form of a working cylinder, e.g. B. a pneumatic or hydraulic cylinder, which are able to move the ring 07 in the axial direction.
• These linear actuators 37 are actuated in order to move the ring 07 of the bearing arrangement 03 in the direction of the opposite bearing arrangement 02 and thus close the sieve 28 relax when the screen cylinder 01 is to be dismantled.
• the linear actuators 37 pull the ring 07 in the opposite direction in order to tighten the screen 28.
• FIGS. 6 and 7, each represent views analogous to FIGS. 2 and 4.
• Elements of this second embodiment which correspond to those already described have the same reference numerals and are not described again.
• This second embodiment differs from the first in that the ring 07 of each bearing arrangement 02; 03 is in one piece and carries a single claw 42 which extends over an angle of 180 ° around the axis of the screen cylinder 01.
• An inner surface 43 of the claw 42 facing the ring 07 is conical, the apex of the cone being separated from the bearing arrangement 02; 03 is turned away.
• the flange 31 also has a conical surface.
• the flange 31 has two sections with different radius, which are in the assembled state by the sides 24; 26 of the claw 42 touching radial surfaces are connected in order to ensure an exact transmission of the rotary movement of the ring 07 to the screen cylinder 01.
• the linear actuators 37 are actuated to tension the screen 28 in preparation for the operation of the screen printing machine, the inner surface 43 of the claw 42 comes into intimate contact with the flange 31.
• the conical shape of the inner surface 43 and the surface of the flange 31 facing it brings about this that a radially outward force acts on the flange 31 along the inner surface 43, which prevents the flange 31 from escaping from the claw 42.
• recessed spring element 44 for. B. compression springs 44 are provided in order to release the contact between the inner surface 43 and the flange 31 when the screen 28 is relaxed for the disassembly of the screen cylinder 01 and thus the removal of the head piece from the bearing arrangement 02; 03 to facilitate.
• each ring or partial ring has only one claw 13; 16 or 42 wears.
• the number of claws can in principle be arbitrary, as long as all claws can be accommodated in an angular range of 180 °, so that they can insert a head piece into the bearing arrangements 02; 03 do not hinder.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Screen Printers (AREA)
• Manufacturing Of Printed Wiring (AREA)
• Paper (AREA)
• Combined Means For Separation Of Solids (AREA)
• Holo Graphy (AREA)

Priority Applications (2)

Applications Claiming Priority (3)

Related Child Applications (4)

Publications (3)

Family

ID=29265044

Family Applications (3)

Family Applications Before (2)

Country Status (8)

Families Citing this family (12)

Family Cites Families (20)

• 2002
  • 2002-05-03 DE DE10219845A patent/DE10219845C1/de not_active Expired - Fee Related
  • 2002-12-16 AU AU2002358436A patent/AU2002358436A1/en not_active Abandoned
  • 2002-12-16 US US10/513,162 patent/US7287467B2/en not_active Expired - Lifetime
  • 2002-12-16 EP EP10189094.5A patent/EP2311635B1/fr not_active Expired - Lifetime
  • 2002-12-16 CN CNB028288858A patent/CN1318214C/zh not_active Expired - Fee Related
  • 2002-12-16 WO PCT/DE2002/004580 patent/WO2003093013A2/fr not_active Ceased
  • 2002-12-16 JP JP2004501169A patent/JP4417830B2/ja not_active Expired - Fee Related
  • 2002-12-16 AT AT02792661T patent/ATE496769T1/de active
  • 2002-12-16 EP EP10189095A patent/EP2311636B1/fr not_active Expired - Lifetime
  • 2002-12-16 DE DE50214889T patent/DE50214889D1/de not_active Expired - Lifetime
  • 2002-12-16 CN CN2007100052542A patent/CN101028754B/zh not_active Expired - Fee Related
  • 2002-12-16 EP EP02792661A patent/EP1501678B9/fr not_active Expired - Lifetime
• 2007
  • 2007-06-20 US US11/820,717 patent/US7458319B2/en not_active Expired - Fee Related
• 2008
  • 2008-12-19 JP JP2008324249A patent/JP4373483B2/ja not_active Expired - Fee Related

Non-Patent Citations (1)

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