EP0195378B1 - Printing device - Google Patents

Description

The invention relates to a printing unit.

Printing units for printing surfaces of printed material are known per se and are used, for example, in the manufacture of electrical add-on elements for printing type designations etc. onto these structural elements.

The invention is based on the object of demonstrating a printing unit which, with a relatively simple construction and with high output, permits flawless printing of printed matter.

To achieve this object, a printing unit according to the invention is designed according to claim 1.

The printing unit according to the invention is characterized by a simple and reliably working construction and delivers flawless printed images which are not transferred directly from the printing forms to the surfaces of the printed material to be printed, but in an indirect printing process using the print transfer surfaces.

In a preferred embodiment of the printing unit according to the invention, the second element is provided with a circular or annular depression, on the bottom of which the at least one printing form is provided. This enables the printing unit to work properly even with a relatively large amount of excess printing ink, which (excess amount) ensures that the at least one printing form is properly colored, and after the printing form has been colored, excess printing ink is used by a scraper or a pulling device from the at least one area provided with a printing form is conveyed into an area on the outer or inner edge of the depression. This excess printing ink, which is conveyed outwards or inwards, is then used again for inking the printing form.

In a further embodiment, the first element consists of two individual elements which are arranged offset to one another in the direction of the first axis of rotation, at least one pressure transmission surface being provided on the sides of the two individual elements of the first element facing each other and the at least two pressure transmission surfaces facing one another in Direction of the first axis of rotation in opposite directions from the rest position, in which the mutually facing pressure transmission surfaces are at a greater distance from one another, can be moved into the working position, in which the mutually facing pressure transmission surfaces are at a smaller distance from one another, the second element at least on two surface areas facing away from each other has a printing form.

This design has the advantage that, with a relatively simple construction and high performance, it is possible to print on printed matter on two surface sides that are turned away from one another perfectly and simultaneously. The two individual elements of the first element are preferably designed in the form of circular disks and have the at least two pressure transmission surfaces on the facing end faces. The second element is also preferably in the form of a circular disk and has at least one printing form on each of the two end faces. However, a plurality of pressure transmission surfaces are preferably provided on each individual element and a plurality of printing forms are provided on the two surface areas of the second element.

Developments of the invention are the subject of the dependent claims.

• Fig. 1 in Seitenansicht die teilweise im Längsschnitt eine Ausführungsform des erfindungsgemäßen Druckwerks;
• Fig. 2 einen Schnitt entsprechend der Linie I-I der Fig. 1;
• Fig. 3 in etwas vereinfachter Darstellung einen Schnitt entsprechend der Linie 11-11 der Fig. 1;
• Fig. 4 in Einzeldarstellung eine Draufsicht auf die mit den Druckformen versehene Seite des zweiten, diese Druckformen aufweisenden Elementes.
• Fig. 5 in ähnlicher Darstellung wie Fig. 1 eine abgewandelte Ausführung des Druckwerkes;
• Fig. 6 in Draufsicht einen Transportteller des Druckwerks nach Fig. 5 zum Zuführen und Abführen des Bedruckgutes an bzw. von der Druckposition;
• Fig. 7 in schematischer Darstellung und in Seitenansicht eine weitere Ausführungsform des Druckwerkes;
• Fig. 8 in vereinfachter Darstellung eine Draufsicht auf eine Stirnfläche des die Druckformen aufweisenden scheibenförmigen Elementes des Druckwerkes nach Fig. 7;
• Fig. 9 im Längsschnitt eine abgewandelte Ausführungsform des Druckwerkes gemäß Fig. 7;
• Fig. 10 einen Schnitt entsprechend der Linie 111-111 der Fig. 9;
• Fig. 11 in vergrößerter Detaildarstellung die Einrichtung zum Aufbringen von Druckfarbe auf die Druckformen zusammen mit dem die Druckformen aufweisenden scheibenförmigen Element bei dem Druckwerk nach Fig. 9.

The invention is explained in more detail below with reference to the figures using an exemplary embodiment. Show it:

• Figure 1 in side view, partially in longitudinal section, an embodiment of the printing unit according to the invention.
• Fig. 2 is a section along the line II of Fig. 1;
• Fig. 3 is a somewhat simplified representation of a section along the line 11-11 of Fig. 1;
• Fig. 4 in individual representation a top view of the side provided with the printing forms of the second element having these printing forms.
• 5 shows a modified version of the printing unit in a representation similar to FIG. 1;
• FIG. 6 shows a top view of a transport plate of the printing unit according to FIG. 5 for feeding and removing the printed matter to or from the printing position;
• Fig. 7 in a schematic representation and in side view a further embodiment of the printing unit;
• 8 is a simplified representation of a top view of an end face of the disk-shaped element of the printing unit according to FIG. 7 having the printing forms;
• 9 shows a modified embodiment of the printing unit according to FIG. 7 in longitudinal section;
• Fig. 10 is a section along the line 111-111 of Fig. 9;
• 11 is an enlarged detail view of the device for applying printing ink to the printing forms together with the disk-shaped element having the printing forms in the printing unit according to FIG. 9.

The printing unit according to FIGS. 1 to 4 has a machine frame or a machine frame which is formed by two plates 1 arranged with their surface sides in vertical planes and parallel and spaced apart from one another, which lie over two with their surface sides in horizontal planes and boards spaced one above the other are interconnected. The two substantially rectangular plates 1 have on their lower side edge in FIG. 1 each in the region of the dorti towards the right end an extension 1 'reaching down from this side edge. On these extensions, the circuit boards 1 and thus the printing unit can be attached via angle pieces 3 to a work table or to a production line where the printed material 4, which in the illustrated embodiment is formed by electrical components, is to be imprinted. The space formed between the two boards 1 is closed in the illustration chosen for FIG. 1 above and on the left and right side by a hood-like housing part 5 which also covers the outer sides of the boards 1.

Between the two boards 1, a drive element 6 is fastened, which in the embodiment shown is formed by an angular gear mechanism, the driven shaft 7 of which is guided through the housing part 5 to the outside and can be connected either directly or via further coupling elements to a drive motor (electric motor), and whose output shaft 8 carries a toothed belt pulley 9. Of course, the drive element 6 can also be a drive motor (electric motor), on the shaft of which the toothed belt pulley 9 is then attached.

Between the plates 1 there is also a step mechanism 10, the driven shaft 11 of which lies parallel to the shaft 8 and extends in the vertical direction and is also provided with a toothed pulley 12 which is connected to the toothed belt pulley 9 via a toothed belt 13. On the upper end of the shaft 11, which is driven continuously by the drive element 6, sits above the toothed rhyme disk 12, a control disk 14 which, on its upper end face facing away from the stepping gear 10, has on its periphery a closed, ring-like edge 15 projecting beyond this end face, which runs concentrically to the axis of the shaft 11, and the height of which changes to form a control curve around the circumference of the control disk 14 such that the edge 15 has a region of maximum height and a region of minimum height which is 180 ° around the axis of the shaft 11 are offset from one another and merge into one another in such a way that the edge 15 in the bend has a height that changes according to a sine line.

The stepping gear 10 furthermore has an output shaft 16, the axis of which also lies in the vertical direction and which projects over the top and over the bottom of the stepping gear 10. A gear 17 is fastened to the end of the shaft 16 projecting above the top of the stepping gear mechanism, which gear is connected to a gear 19 via an intermediate gear 18 rotatably mounted on the upper plate 2. The gearwheel 19 is seated on a shaft 20 which also runs in the vertical direction with its axis and which is rotatably mounted in the upper and lower plate 2 and at the same time is also axially displaceable.

In the area between the two plates 2, the shaft 20 is provided with a collar or with a section 21 with an enlarged cross-section, against which the upper end of a compression spring 22 which surrounds the shaft 20 rests, the lower end of which rests against one on the shaft 20 supports in the longitudinal direction of this shaft displaceably arranged sleeve 23, which in turn bears with its underside facing away from section 21 against the upper side of lower plate 2 or against a bearing element provided there. By the compression spring 22, the shaft 20 is for an axial movement upwards, i.e. biased in the direction of arrow A of FIG. 1.

At the lower end of the shaft 20, which protrudes beyond the underside of the lower plate 2, a plate-like or circular disk-like element 24 is fastened, which in the area of its circumferential surface in the illustrated embodiment has four essentially circular-shaped elements 25 made of elastic material, e.g. made of rubber or elastic plastic. The elements 25, each having the same radial distance from the axis of the shaft 20 and with their cylinder axis parallel to the axis of the shaft 20, are offset by 90 ° in each case about the axis of the shaft 20 and are each of the same length over the lower, ie face of the element 24 facing away from the lower circuit board 2 and form the pressure transmission surfaces at their lower, convexly curved surface 25 '.

A roller 26 bears against the upper end of the shaft 20 projecting above the upper circuit board 2 and is mounted on one end of a double-armed lever 28 by means of a bearing pin 27 so as to be rotatable about an axis running perpendicular to the circuit boards 1. The lever 28, which is pivotally attached to these boards approximately in its central region with the aid of a hinge pin 29, the axis of which likewise runs perpendicular to the surface sides of the boards 1, has a further roller 30 at its other end, which is there with the help an axis 31, is also rotatably mounted about a spatial axis running perpendicular to the surface sides of the circuit boards 1 and bears against the upper side of the edge 15 forming the control curve. When the shaft 11 rotates, the shaft 20 is moved back and forth in the axial direction via the control curve formed by the edge 15 and the lever 28 (in cooperation with the compression spring 22), namely once every full rotation of the shaft 11 (arrow A) and then down once (arrow B).

On the end of the shaft 16 projecting over the underside of the stepping gear 10 and over the lower circuit board 2, a second circular disk-like element 32 is fastened, which is provided on the circumference on its end surface facing the lower circuit board 2 with a self-contained edge 33 which extends over the front surface facing the lower board 2 protrudes. Through this edge 33, the element 32 is cup-shaped or plate-like. Within the A region enclosed by the edge 33 rests against the end face of the element 32 there, with a disk 34 provided with a central opening, which, in the embodiment shown, is provided with several different printing forms 35a, 35b and 35c at least on its surface side facing the lower plate 2 (FIG 4), which are each formed by line-shaped or punctiform depressions in this surface side. Depending on the number of elements 25 on element 24, the different printing forms 35a, 35b and 35c are each provided four times, in such a way that the printing forms of the same type are offset from one another by 90 ° about the axis of shaft 16, ie in the illustrated embodiments the printing forms 35a, 35b and 35c are each arranged in four groups around the axis of the shaft 16, with a printing form 35a followed by a printing form 35b and a printing form 35c following this in each group, offset by 30 ° in each case. Of course, it is also possible to provide more than three or fewer than three printing forms in each group. Furthermore, it is also possible to use more or less than four groups of printing forms in accordance with the number of elements 25 on element 24. The element 32 and the flat disk 34 provided with the printing forms are clamped between a collar 36 and a clamping plate 38 held at the lower end of the shaft 16 by means of a screw 37. A pin 39 projects beyond the lower end face of the collar 36 facing away from the lower plate 2 and extends through an adjustment 40a, 40b or 40c provided on the plate 34 into a bore 41 in the element 32. The number of adjusting bores 40a-40c corresponds to the number of different printing forms 35a-35c, the adjusting bores being offset from one another at the same angular distances from one another about the axis of the shaft 16 that the (angular distance) the different printing forms 35a-35c have in a group from one another . By inserting the centering pin 39 into a centering hole 40a-40c, it is therefore possible to select for the printing process only those printing forms which are assigned to this centering hole and are of the same type, so that it is also possible to use the same 4 according to the selection made in each case To provide disc 34 with different printing.

Between the circular cylindrical circumferential surface of the collar 36 and the inner surface of the edge 33 an annular, upwardly open recess is formed, on the bottom surface of which the printing forms 35a-35c are located. As shown in FIG. 1, the two elements 24 and 32 are further arranged with respect to one another such that these elements overlap with a partial area, the element 24 being arranged above the element 32 such that the elements 24 and 32 are in the vertical direction overlap in a partial area, in which partial area the movement path, on which the elements 25 rotate when the shaft 20 rotates, lies directly above the movement path on which the printing forms 35a-35c, which are each arranged with the same radial distance from the axis of the shaft 16, rotate the shaft 16 revolve.

On the side of the shaft 16 facing away from the element 24, a device 42 for applying printing ink is provided on the element 32, which device is essentially formed by a squeegee or by a scraper 43 which from above into the annular space between the collar 36 and the edge 33, and its lower edge bears against the surface side of the disk 34 provided with the printing forms 35a-35c and facing the lower plate 2. As shown in FIG. 2, the part of the scraper 43 protruding into the annular space is formed by a curved wall 44 with its surface sides running essentially in the vertical direction, which is arranged in such a way that in FIG. 2 by the arrow C indicated direction of rotation of the element 32, the concave side of the wall 44 which forms the front side of the scraper 43 in the direction of rotation, that is to say on this side of the scraper 43 there is a space 45 ′ which is partially enclosed by the wall 44 and in which there is a nozzle opening (not shown) Printing ink is applied to the top of the disc 34 and in which there is preferably always a certain excess of printing ink. This printing ink is then distributed with the lower scraper edge of the scraper 43 or the wall 44 in such a way that the printing ink, after the disk 34 has moved past the scraper 43, mainly at least on the annular surface area on which the printing forms 35a-35c are arranged only in the punctiform or linear depressions forming these printing forms. The scraper 43 is held at one end of a horizontal holding arm 45, which is fastened at its other end to one of the two boards 1 via a holding rod 46. In the direction of rotation of the element 32 (arrow C) following the scraper 43, a pulling device 47 is provided which is fastened to the other board 1 by means of a holding arm 48 and a holding rod 49 which extends obliquely upwards. In the illustrated embodiment, the pulling device 47 consists of a cutting blade 50, which in the simplest case is formed by a razor blade and which is arranged with its surface sides obliquely to the upper side of the disk 34 in such a way that the cutting blade 45 points to the top of the disk 34 Includes angle, which opens in the direction of rotation (arrow C) of the element 32. The cutting blade 50, which is held by a holding block 51 and by screws (not shown) on the holding arm 48 by clamping, lies with its, in relation to the direction of rotation (arrow C) of the element 32, the front cutting edge 52 against that with the printing formes 35a-35c provided area of Top of the disc 34 on. Excess printing ink that may still be present is thus drawn off or scraped off by the cutting blade 50 or its cutting edge 52 from the region of the upper side of the disk 34 provided with the printing forms. Since the effective length of the cutting edge 52 is smaller than the width of the annular space between the collar 36 and the edge 33 and thus the cutting edge 52 is in particular also a distance from the circular cylindrical peripheral surface of the collar 36 and moreover also obliquely to the direction of rotation (arrow C) of the element 32 is arranged in such a way that the end of the cutting edge 52 adjacent to the collar 36 lies on a line running radially to the axis of the shaft 16, which line corresponds to the corresponding line for the end of the cutting edge 52 adjacent to the edge 33 (direction of rotation) C) of the element 32 leads, excess printing ink drawn off from the cutting edge 52 is conveyed radially inward from the surface area having the printing formes and, after moving past the pulling device 47, forms a bead-like supply of printing ink surrounding the collar 36, which is then returned by the scraper 43 (if necessary with new printing ink) evenly distributed and z for inking the printing forms 35a-35c) is also used. It goes without saying that for this process the wall 44 extends as close as possible to the collar 36.

The mode of operation of the printing unit can be described as follows:

The printed material 4 or the individual components are fed to the printing unit in a clocked manner via a conveying device 53, this conveying device being driven synchronously with the drive of the printing unit.

Since the gears 17 and 19 have the same number of teeth and are drivingly connected to one another via the gear 18, both elements 24 and 32 are rotated in the same direction and at the same speed, as indicated by the arrows C and D.

The stepper gear 10 is designed so that during a full rotation of the shaft 11, the elements 24 and 32 perform a movement step of 90 ° with a preceding or subsequent standstill phase, in such a way that whenever the shaft 20 is out of its upper Position is lowered by a certain amount in the direction of arrow B, the two elements 24 and 32 stand still and one element 25 is directly opposite a printing form 35a or 35c and another element 25 is a surface of the printed material 4. When the shaft 11 is rotated further and the shaft 20 is further lowered (when the elements 24 and 32 are stationary), one element 25 comes into contact with its underside for taking up a printed image with a printing form and the other element 25 with its underside for transmitting the printed image on the printed material 4 with the surface of this printed material to the system. The shaft 20 then moves upward in the direction of arrow A. From a certain. Position, i.e. for example, when the underside of the elements 25 is level higher than the upper edge of the edge 33, the elements 24 and 32 are each rotated further by one switching step (angular step of 90 °). Subsequently, the shaft 20 is lowered again so that a print record can again be taken up by an element 25 and a print image can be transferred from an element 25 to a new, not yet printed printed material 4.

The printing unit according to FIGS. 5 and 6 differs from the printing unit according to FIGS. 1 to 4 only in that an essentially circular disk-shaped turntable 54 is provided instead of the conveying device 53. The turntable 54 is fastened to a shaft 55 which is arranged parallel to and at a distance from the shaft 20 and which is mounted on the boards 2 and on a stationary auxiliary board 56 provided under the turntable 54, which is connected, for example, to the lower board 2 via spacer elements is rotatably supported that a portion of the element 24 and a portion of the circular disk-shaped turntable 54 overlap. At the upper end, the shaft 55 carries a gearwheel 57 which is connected to the gearwheel 19 via an intermediate gearwheel 58 mounted on the upper circuit board 2, so that the turntable 54 is driven in rotation and clocked synchronously with the drive of the printing unit.

On its upper side facing the elements 25, the turntable 54 is provided with groove-like recesses 59 which extend radially to the axis of the shaft 55 and are open to the upper side and to the edge 54 'of the turntable. The number of recesses 59, which are arranged at uniform angular intervals around the axis of shaft 55, is equal to the number of elements 25. In each recess 59, a lever-like clamping jaw 60 can be pivoted at one end with the aid of a hinge pin 61 lying parallel to the axis of shaft 55 mounted, the pivot pin 61 of the shaft 55 being closer than the free end of the clamping jaw 60 which extends approximately to the circumferential surface 54 '. A compression spring 62 prestresses each clamping jaw 60 so that when the spring 62 is relaxed, one of its jaws is radial to the shaft 55 extending longitudinal sides, namely with the longitudinal side serving as the holding surface 63 is directly adjacent to an extension 64 which has each recess 59 in the region of the peripheral surface 54 '. At its free end, each clamping jaw 60 has an upwardly projecting pin 65 which lags the associated extension 64 in the direction of rotation of the turntable 54 (arrow E).

On the top of the auxiliary circuit board 56, two holding blocks 66 are provided, offset from one another by 180 ° about the axis of the shaft 55, on each of which there is a stop element 67 designed as a lever, parallel to the axis of the shaft 55 lying hinge pin 68 is pivotally mounted at one end. The other end of each stop element 67 is finger-like with a reduced cross-section and has a nose-like projection 69 facing the shaft 55, which forms an inclined contact surface for the pins 65 on one side. Each stop element 67 is prestressed by a compression spring such that the finger-like end 67 'with the projection 69 lies in the movement space of the pins 65. The two stop elements 67 are further arranged so that their projections 69 lie on a connecting line which is approximately perpendicular to the line L which intersects the axes of the shafts 16, 20 and 55.

Whenever a pin 65 moves past the projection 69 of a stop element, the corresponding clamping jaw 60 is pivoted against the action of the spring 62 in the direction of the arrow H, so that the conveyor 70 on which the components 4 move in the direction of the arrow F can be supplied, a component 4 can be moved into the extension 64 or a component 4 can be delivered from an extension 64 to the conveyor device 71, with which the printed components are removed in the direction of the arrow G. When moving the turntable 54, each pin 65 comes out of engagement with the projection 69 again, so that the jaws in question pivot against the arrow H back to their rest or clamping position and the component 4 transferred from the conveyor 70 to the turntable 54 in the extension 64 is clamped. It is understood that the rotary movement of the turntable 54 always has a standstill phase when there is an extension 64 on the conveying direction 70, an extension 64 on the conveyor 71 and an extension 64 under an element 25, so that this is in the last-mentioned extension held component 4 can be printed by the downwardly moving element 25 on its surface projecting above the top of the turntable 54. The conveyor devices 70 and 71 are conventional conveyor devices, for example linear conveyors (e.g. vibration conveyors), in which the components 4 are guided in a guide rail. Additional devices, not shown, such as air outlet nozzles or mechanical elements for moving the components 4 are preferably provided for introducing the components 4 from the conveying direction 70 into the respectively available extension 64 or for bringing the components 4 out of the extension 64 onto the conveying device 71 .

In the embodiment according to FIGS. 7 and 8, 101 is the work table with its upper side lying in a horizontal plane of an otherwise not shown machine frame or machine frame. At the top of the work table 101, the printing unit 102, the drive elements of which are accommodated in a housing 103, is fastened where, for example, the printed material is to be imprinted at the end of a production line. The printed material is formed by electrical components 104, which are strapped in a quasi-radial form and are held on a belt 105 which, with its longitudinal extent, is perpendicular to the plane of the drawing in FIG. 7. By suitable, provided on the top of the work table 101 guide and drive means, which are shown for the sake of simplicity only as guide rails 106, the belt 105 is upright, i.e. with its surface sides in vertical planes and thus lying perpendicular to the top of the work table 101 such that the bodies 104 'of the components 104 are arranged above the upper edge of the belt 105 or the connecting wires 107 above the upper edge of the belt 105 in the vertical direction upwards stand away and carry the component bodies 104 'at their upper end. The belt 105 and thus also the components 104 held on it are moved clocked in the horizontal direction or in the direction perpendicular to the plane of the drawing in FIG. 7.

Outside the housing 103, two circular disk-like elements 108 and 109 are provided in such a way that the two facing end faces 110 and 111 of these elements are at a distance from one another but parallel to one another, the axes of the elements 108 and 109 passing through the respective center point being coaxially with one another and in the horizontal direction, ie run in the direction parallel to the top of the work table 101 and in the direction perpendicular to the direction of movement of the belt 105.

The element 108 is secured against rotation at an end projecting from the housing 103 of a hollow shaft 112 which is rotatably mounted in the interior of the housing 103 or on a circuit board 113 and is displaceable in the axial direction, which (circuit board) connects the interior of the housing to the Elements 108 and 109 facing side completes. Compared to the element 108, the element 109, which is at a greater distance from the circuit board 113, is held against rotation at the end of a shaft 114, which with this end also protrudes beyond the housing 103 and is rotatable and axially in the housing 103 or in the hollow shaft 112 is slidably mounted. The axes of the hollow shaft 112 and the shaft 114 are coaxially with one another and coaxially with the axes of the elements 108 and 109 and thus also extend in the horizontal direction. By means of drive means, not shown, the hollow shaft 112 and the shaft 114 and thus also the elements 108 and 109 seated on these shafts are driven in a rotating and clocked manner in such a way that after each rotation step, ie during each standstill phase following a rotation step, the hollow shaft 112 and thus also the element 108 from a rest position at a smaller distance from the circuit board 113 according to the arrow A 'into a working position at a greater distance from the latter The board moves and then moves back again, this stroke taking place in the direction of the axis of the hollow shaft 112. At the same time, in each standstill phase, the element 109 is first moved according to the arrow B 'from a rest position with a greater distance from the circuit board 113 into a working position with a smaller distance from this circuit board and then moved back into the rest position against the arrow B'. This stroke of the element 109, which corresponds in size to the stroke of the element 108, also takes place in the direction of the axis of the hollow shaft 112 or the shaft 114. To achieve the clocked rotary movement, the elements 108 have the same diameter and rotate synchronously and with the same direction of rotation and 109 is provided in the interior of the housing 103 a step mechanism which is driven by a drive motor, not shown, which either transports the belt 105 either via the same step mechanism or via a further step mechanism, so that the belt is also moved in steps 105 and thus the components 104 takes place synchronously with the rotational movement of the elements 108 and 109. To achieve the strokes (arrows A 'and B') of the elements 108 and 109, a gear arrangement, also not shown and having at least one control curve, is also provided in the interior of the housing 103, this gear arrangement also being designed such that the stroke movements of the elements 108 and 109 take place synchronously or simultaneously in the opposite direction.

In the area of the circumferential surface of the elements 108 and 109, on the mutually facing end faces 110 and 111, pressure elements 115 and 116, which are formed in a substantially circular cylindrical manner and are provided at the same radial distance from the axis of the shaft, are provided at uniform angular intervals around the axes of these elements 114 or hollow shaft 112 are arranged and made of elastic material, for example made of rubber or elastic plastic. The elements 115 and 116, which lie with their cylinder axes parallel to the axis of the shaft 114 or hollow shaft 112, are fastened at one end or on one end face to the end face 110 or 111 of the associated element 108 or 109. At the other end or on the other end face, the pressure elements are convexly curved and form the pressure transmission surfaces 115 ′ or 116 ′ there, all pressure transmission surfaces 115 ′ being the same distance from the end face 110 and all pressure transmission surfaces 116 ′ being the same distance from the end face 111 exhibit. Furthermore, the pressure elements 115 and 116 in the illustrated embodiment are arranged such that in the direction of the axis of the shaft 114 or hollow shaft 112, each pressure element 115 on the element 108 is directly opposite a pressure element 116 on the element 109, which also means that the number of pressure elements 115 is equal to the number of printing elements 116.

Above the shaft 114 or hollow shaft 112, a shaft 117 is rotatably mounted in the housing 103 or in the plate 113, the axis of which lies parallel to the axis of the shaft 114. At its end protruding from the housing 103, the shaft 117 carries a circular-disk-shaped element 118, which is provided on its two vertical end faces running perpendicular to the axis of the shaft 117 each with an annular recess open to the respective end face, the respective bottom surface 119 and 120 is parallel to the end faces 110 and 111 of the elements 108 and 109 and is provided in the region of the circumference with printing forms 121, which are each formed by line-shaped or dot-shaped depressions on these floor surfaces. The printing forms 121 on each bottom surface 119 and 120 are each arranged at equal angular distances around the axis of the shaft 117 and are also each at the same radial distance from this axis, with each printing form 121 on the bottom surface 119 having a printing form 121 on the bottom surface 120 is directly opposite in the direction of the axis of the shaft 117. All printing forms 121 on each bottom surface 119 and 120 are of identical design, the printing forms 121 on the bottom surface 119 can be different from the printing forms 121 on the bottom surface 120, i.e. The printing forms 121 on the bottom surface 119 are used, for example, for printing technical data on one side of the cuboid-shaped component bodies 104 'and the printing forms 121 on the bottom surface 120 for printing a manufacturer's note on the other opposite side of the component bodies 104'. In principle, it is of course also possible to design the printing forms 121 on the bottom surface 119 identically with the printing forms 121 on the bottom surface 120, so that the printed component bodies 104 'can be read completely from both sides. The thickness of the element 118 in the area of the printing form 121, i.e. the distance of the bottom surfaces 119 and 120 is approximately equal to the thickness of the component body 104 'in the direction of the axis of the shaft 114, i.e. approximately equal to the distance between the two surfaces of the component body 104 'to be printed.

In principle, it is also possible, at least on one side of the element 118, not to provide the pressure surfaces 121 directly on the bottom surface 119 or 120 there, but on a surface side of the disk 34 described above.

The shaft 117, which is rotatably but axially non-displaceably, is also driven in a rotating and clocked manner, namely in synchronism with the drive of the elements 108 and 190, the element 118 preferably being driven in the same direction as the drive of the elements 108 and 109 , ie all elements have the same direction of rotation. Element 118 has the same diameter as elements 108 and 109. In addition, shaft 117 is in the housing 103 mounted in such a way and the element 118 fastened to this shaft in such a way that it extends with a partial area into the space between the elements 108 and 109, in such a way that a printing element 115 forms a printing form 121 in each phase of the elements 108, 109 and 118 at a standstill on the bottom surface 119 and a pressure element 116, a printing form 121 on the bottom surface 120 in the direction of the axes of the shaft 117 is directly opposite. This also means that the distance that the axes of the shafts 114 and 112 have from the axis of the shaft 117 is equal to the sum of the radial distance of the printing forms 121 from the axis of the shaft 117 and the radial distance of the printing elements 115 and 116 from the axis of the shaft 114.

Two devices 122 and 123 for coloring the printing forms 121 with printing ink are also provided on the element 118. With these devices, which are designed to feed the printing ink and are designed in a squeegee manner, it is achieved that the printing forms 121 which pass through the device 118 when the element 118 rotates are provided with printing ink only in the region of the linear or dot-shaped depressions forming these printing forms.

The angular distance that the pressure elements 115 and 116 have on the elements 108 and 109 from one another corresponds in each case to one rotation step of these elements. Likewise, the distance between the printing forms 121 on each bottom surface 119 and 120 corresponds to a turning step of the element 118. The number of printing forms 121 on the bottom surfaces 119 and 120, the number of printing elements 115 and 116 on the elements 108 and 109 are otherwise in the The size of the turning steps of these elements is adjusted so that in each standstill phase of these elements not only a printing form 121 is opposite each printing element 115 and 116, but the component body 104 'of a component is located between two other printing elements 115 and 116.

FIGS. 9 to 11 show in detail a printing unit, which is designed essentially in the same way as the printing unit according to FIGS. 7 and 8, and differs from the printing unit in FIGS. 7 and 8 only in that an element instead of the element 118 118 'is used with flat end faces, on each of which a disk 34 having the printing plates 35 is provided, each disk 34 being designed and fastened in the manner described in the embodiment according to FIGS. 1 to 4.

A further circuit board 113 ′ is provided in the interior of the housing 103 parallel to and at a distance from the circuit board 113. The drive motor 124 (electric motor) with a gear 125 for driving the printing unit is provided on the upper edge of both boards. A rhyme disk 127 sits on the output shaft 126 of the transmission, which is connected via a toothed belt 128 to a belt pulley 129, which sits on the input shaft 130 of a stepping transmission 131. On the shaft 130 there is also a control disk 132 with a self-contained annular groove 133, which forms two control cams 134 and 135 on their mutually facing lateral surfaces, each of which is designed similarly to the control curve formed by the edge 15 and in one about the axis of the shaft 130 extending portion each have a greater distance and in a different portion a smaller distance from the board 113 '. On the end of the shaft 117 which projects to the left over the circuit board 113 'and forms the output shaft of the stepping transmission 131 arranged between the two circuit boards 113 and 113', there is a gearwheel 137 which is connected via an intermediate gearwheel rotatably mounted on the circuit board 113 ' 138 is connected to a gear wheel 139, the latter being fixed on the hollow shaft 112. The end of the shaft 117 protruding to the right over the circuit board 113 carries the element 118 '.

In the interior of the housing 103, two further boards 140 and 140 'are provided in parallel and at a distance from one another, their surface sides being perpendicular to the surface sides of the boards 113 and 113' and being connected to these boards. Between the plates 140 and 140 ', a hinge pin 141 is supported at both ends, the axis of which lies in an axial direction perpendicular to the axis of the hollow shaft 112 or shaft 114. On the hinge pin 141, two double-armed levers 142 and 143 are each pivotably mounted approximately in the middle. The two levers carry rollers 144 and 145 at their upper ends, each of which can be rotated about an axis parallel to the axis of the pivot pin 141. The roller 144 of the lever 142 lies against the control cam 134 and the roller 145 of the lever 143 against the control cam 135. In the interior of the housing 103, at the end of the shaft 114 facing away from the elements 108 and 109, a disk 146 is provided which has a larger outer diameter than the shaft 114. On the end of the hollow shaft 112 facing away from the elements 108 and 109, a sleeve 147 forming a slide bearing is seated inside the housing 103. The lower end of the lever 142 lies with a slide body 148 attached to this end against the end face of the elements 108 and 109 facing the Disc 146 on. A sliding body 149 fastened to the lower end of the lever 143 bears with its side facing the elements 108 and 109 against the sleeve 147.

Between the elements 108 and 109, several guide elements are provided which, while allowing the elements 108 and 109 to move in the direction of the arrows A 'or B' or in the opposite direction, prevent the elements 108 and 109 from moving relative to one another by the Can rotate axis of shaft 114. These guide elements each consist of a bolt 150 which is held with a thread in a threaded bore in the element 109, with its axis parallel to the axis of the shaft 114 lies and extends with one end into a bore 151 of the element 108. At this end, a sliding sleeve 152 is secured against rotation on the bolt 150 and slides with its outer surface on the wall of the bore 151. The elements 108 and 109 are also coupled to one another via the bolts 150 such that when the hollow shaft 112 is rotated, the element 109 seated on the shaft 114 is also rotated via the element 108 fastened on this hollow shaft. Between the mutually facing end faces of the elements 108 and 109, a plurality of compression springs 153 are provided, which push the elements 108 and 109 apart into their respective rest positions. The translation of the stepping gear 131 and the control cams 134 and 135 are designed so that after each rotation step of the shaft 117 and the shafts 112 and 114 during the standstill phase following this rotation step, the levers 142 and 143 by the control cams 134 and 135 from a rest position in a working position, ie the lever 142 in the direction of arrow D 'and the lever 143 against this direction pivoted about the hinge pin 141 and then pivoted back into the rest position, so that the elements 108 and 109 in each standstill phase from the rest position a working stroke Execute in direction A 'or B' and back to the rest position. The stepping transmission 133 is preferably designed such that when the shaft 130 rotates fully, the shaft 117 carries out four rotary steps, each with a subsequent standstill phase.

FIG. 11 shows in detail the device for inking the printing forms 35a-35c on the disks 34. This device again consists of the two elements 122 and 123. In the direction of rotation of the element 118 ', the elements 122 and 123 are each following Wiping devices 154 and 155 are provided, each consisting of a block 158 fixed to the element 122 or 123 and a block 158 held on this block with the aid of guide pins 157 in the direction perpendicular to the end faces of the element 118 ', which carries a knife-like scraper 159, which rests resiliently against the surface side of the disk 34 in question provided with the printing formes 35a-35c, specifically because of the compression spring 160 acting between the blocks 156 and 158. In FIG. 11, the two are each of cutting blades formed scraper based on the direction of rotation of the element 118 'arranged so that this scraper with the respective Iligen surface of the ring 34 form an acute angle, which opens in the direction of rotation of the element 118 '(arrow C'). However, it is also possible to arrange the wipers 159 and also the wipers 50 according to FIGS. 1 to 4 in such a way that this wiper forms an acute angle with the surface side of the disk 34, which angle is opposite to the direction of rotation of the element 118 'or Element 32 opens.

The operation of the printing devices according to FIGS. 7 to 10 can be described as follows:

In each standstill phase of the elements 108, 109 and 118, two printed images are transferred from the colored printing areas 121 to the printing transfer areas 115 'and 116' at the same time. The print transmission surfaces 115 'and 116' provided with these print images then, after one or more rotation steps of the elements 108 and 109, reach the area where a component body 104 'is located between these elements, so that the print images then (in a standstill phase) can be printed on the surface sides of a ready component body 104 '.

Since very small, easy-to-read imprints are to be achieved with the described printing units and for this a very exact rotary movement of the elements is required, it can be expedient to provide a braking device for a shaft, as is shown in FIG. 5 with the braking device 72 for the shaft 20 is indicated. This braking device avoids inaccuracies that could result from the play of the driving gears 17 to 19, since a constant, braking torque is constantly exerted on the shaft 20.

Claims (15)

1. Printing unitforapplying a print to a surface of articles (4) to be printed lying in a printing plane, having a first element (24, 108, 109), which is mounted rotatably about a first axis of rotation (20, 112, 114) on a machine frame (1, 2), is driven in cycles, and has on at least one surface region at least one print transfer surface (25', 115', 116'), having a second element (32, 118) which is mounted on the machine frame rotatably about a second axis of rotation (16,117) extending parallel to the first, is likewise driven in cycles, and has on at least one surface region (34,119,120) facing the first element (24, 108, 109) at least one printing forme (35a, 35b, 35c, 121), and having a device (42, 122, 123) for applying printing ink to the at least one printing forme (35a, 35b, 35c, 121), at least one of the two elements being movable relative to the other back and forth between two positions in such a way that the at least one print transfer surface (25', 115', 116') in a first position (operating position) rests against the at least one printing forme (35a, 35b, 35c, 121) and, in a second position (position of rest), has a spacing from the printing forme, the at least one printing forme (35a, 35b, 35c; 121) and the at least one print transfer surface (25', 115', 116') furthermore being arranged in planes extending vertically in relation to the axes of rotation (16,20; 114,117), and the elements (24, 32; 108, 109, 118) being movable relative to one another in the direction of the axes of rotation (20, 16; 114,117).

2. Printing unit according to Claim 1, characterized in that the number of print transfer surfaces (25'; 115', 116') on the at least one surface side of the first element is equal to the number of printing formes (35a, 35b, 35c; 121) on the side of the second element facing this surface side or to an integral multiple thereof, and/or in that the number of printing formes (35a, 35b, 35c; 121) on the at least one surface side of the second element is equal to the number of print transfer surfaces (25'; 115', 116') on the side of the first element facing this surface side or to an integral multiple thereof.

3. Printing unit according to Claim 1 or 2, characterized in that the print transfer surfaces (25'; 115', 116') are arranged in each case distributed at equal angular intervals about the first axis of rotation, and/or in that the printing formes (35a, 35b, 35c; 121) are arranged in each case at equal angular intervals about the second axis of rotation (16, 117).

4. Printing unit according to one of Claims 1 to 3, characterized in that at least two groups of different printing formes (35a, 35b, 35c) are provided on the second element, the printing formes of each group being mutually offset by in each case an equal first angular interval about the second axis of rotation and the printing formes of each group being offset in relation to the printing formes of another group by a second angular interval, and in that the second element (32) can be attached to a shaft (16), forming the second axis of rotation, in different positions corresponding to the second angular interval.

5. Printing unit according to one of Claims 1 to 4, characterized in that the print transfer surfaces (25'; 115', 116') are formed by the free ends of projections (25; 115, 116), preferably made of elastic material, which (projections) protrude over the surface of the first element (24; 108,109) facing the second element (32; 118).

6. Printing unit according to one of Claims 1 to 5, characterized in that the second element (32) has on its surface side facing the first element (24) a circular or annular indentation, which is open towards the first element (24) and closed towards the circumference, on the bottom surface of which the printing formes (35a, 35b, 35c) are provided, a scraper (43) of the device (42), formed, for example, by a curved wall (44), preferably extending into the indentation for applying the printing ink and resting with its scraper edge against the bottom surface of the indentation.

7. Printing unit according to Claim 6, characterized in that, following the scraper (43) in the direction of rotation of the second element (32), there is provided a pulling-off device (47) which extends into the indentation and has a blade (52) resting against the bottom surface of the indentation, the blade (52) preferably extending obliquely to the direction of rotation (C) of the second element (32) and having a spacing from the inner and/or outer boundary surface (36, 33) of the indentation.

8. Printing unit according to one of Claims 1 to 7, characterized in that the first element (24; 108,109) is attached to at least one shaft (20; 112,114) which is mounted in the machine frame (1, 2,103) so as to be rotatable and axially displaceable and is movable back and forth in the axial direction by a control cam (15; 134,135) which is provided on a continuously rotating shaft (11; 136).

9. Printing unit according to one of Claims 1 to 8, characterized in that the first element (24; 108, 109) and the second element (32; 118) are attached to shafts (20, 16; 112, 114, 117) which are interconnected in terms of drive, and one of which is the output shaft of a stepping gear (10; 131), the control cam (15; 134, 135) preferably being provided on the input shaft of the stepping gear (10, 131

10. Printing unit according to one of Claims 1 to 9, characterized in that the first element is composed of two individual elements (108,109) which are arranged mutually offset in the direction of the first axis of rotation (112, 114), in that at least one print transfer surface (115', 116') is provided on each of the mutually facing sides (110, 111) of the two individual elements (108, 109) of the first element, in that the at least two mutually facing print transfer surfaces (115', 116') are movable in the direction of the first axis of rotation (112, 114) in opposite directions from the position of rest, in which the mutually facing print transfer surfaces (115', 116') have a relatively large spacing from each other, into the operating position, in which the mutually facing print transfer surfaces (115', 116') have a smaller spacing from each other, in that the second element (118) has at least one printing forme (121) on each of two surface regions (119, 120) facing away from each other, in that the movement path of the two surface regions (119, 120), having in each case at least one printing forme (121), of the second element (118) extends in a partial section between the movement paths of the at least two print transfer surfaces (115', 116'), and in that two printing planes are formed between the movement paths of the at least two print transfer surfaces (115', 116'), the first individual element (108) of the first element preferably being attached to a hollow shaft (112) and the second individual element (109) of the first element to a shaft (114) which extends at. least with a partial length into the hollow shaft (112), and the hollow shaft (112) being mounted rotatably and axially displaceably on the machine frame (103, 113) and the shaft (114) of the second individual element (109) being mounted rotatably and axially displaceably in this hollow shaft and/or on the machine frame (103, 113), and/or the second element (118) preferably being attached to a shaft (117) which is mounted rotatably, but not axially displaceably in the machine frame (103, 113).

11. Printing unit according to Claim 10, characterized in that the second element (118) is constructed in the form of a circular disc and has in each case at least one printing forme (121) on each of the two end faces (118, 120) extending perpendicular to the second axis of rotation (117).

12. Printing unit according to Claims 10 or 11, characterized in that at least one individual element (108, 109) of the first element is constructed in the form of a circular disc and has at least one print transfer surface (115', 116') on its end face (110, 111) facing the other individual element and extending perpendicular to the first axis of rotation (112, 114).

13. Printing unit according to one of Claims 10 to 12, characterized in that, in the direction of the first axis of rotation (112, 114), the at least one print transfer surface (115') on one individual element (108) is located immediately opposite the at least one print transfer surface (116') on the other individual element (109) of the first element, and in that the at least two printing formes (121) on the two surface regions (119, 120) of the second element (118) are provided congruently on the second element (118) in the direction of the second axis of rotation.

14. Printing unit according to one of Claims 10 to 13, characterized in that the number of print transfer surfaces (115') on the one individual element (108) is equal to the number of print transfer surfaces (116') on the other individual element (109), and/or in that the number of printing formes (121) on the one surface region (119) of the second element (118) is equal to the number of printing formes (121) on the other surface region (120) of the second element (118).

15. Printing unit according to one of Claims 10 to 14, characterized in that the device for applying printing ink is formed by two individual devices (122, 123), each of which is provided in a stationary manner on one surface region (119, 120) of the second element (118).

Images