Patent Grant
10898919
The invention concerns a coating apparatus for coating cylindrical hollow bodies, with a machine frame and a workpiece rotary table mounted on the machine frame so that it can rotate about a rotary axis, which is equipped with several holding mandrels which are rotatably mounted on the workpiece rotary table and which are designed to hold cylindrical hollow bodies, as well as with a coating station arranged on the machine frame. The invention also concerns a process for coating cylindrical hollow bodies.
From the EP 3 088 090 A1 a coating device for coating an outer surface of a coating object is known, comprising a dispensing device for providing a continuous or discontinuous coating stream and a receiving device for receiving and positioning a coating object opposite to the dispensing device, wherein said dispensing means comprises a dispensing nozzle and a coating conveying means fluidly communicating with said dispensing nozzle, said coating conveying means being adapted for pressurized delivery of coating to said dispensing nozzle, and wherein said coating conveying means is adapted for providing hydrostatic pressure to said coating and said exit nozzles are adapted for dispensing coating filaments in response to hydrostatic pressure to said coating.
The task of the invention is to provide a coating apparatus with which a cost-effective coating of an outer surface of a cylindrical hollow body can be realized.
This task is solved for a coating apparatus having a machine frame and a workpiece rotary table which is mounted on the machine frame so as to be rotatable about an axis of rotation and which is equipped with a plurality of holding mandrels which are each rotatably mounted on the workpiece rotary table and which are designed to receive cylindrical hollow bodies, and with a coating station arranged on the machine frame, wherein the coating station comprises a coating roller which is rotatably mounted on the coating station, wherein an axis of rotation of the holding mandrel and an axis of rotation of the coating roller are aligned parallel to one another, the coating roller having a coating region and a free-wheeling region on a circumferential surface, the coating region being a circular cylinder segment with a constant circular radius and is coaxial with the rotational axis of the coating roller and wherein the free-wheeling region is formed from surface sections which each have a distance from the rotational axis of the coating roller which is smaller than the circular radius.
The task of the coating roller is to apply a coating on the outer surface of the cylindrical hollow body in the course of a rolling movement, in particular a slip-free rolling movement, of the coating area on the outer surface of the cylindrical hollow body which may be for example an aerosol can blank made of aluminium or a tube blank made of plastic. For this rolling movement, an opposite rotation of the cylindrical hollow body and the coating roller, which is held on the mandrel, is provided. It is also provided that the coating area of the coating roller is in contact with the outer surface of the cylindrical hollow body to allow a contact, preferably a line contact, between the coating area and the outer surface. On the other hand, it is provided that the free-wheeling region of the coating roller cannot come into physical contact with the outer surface of the cylindrical hollow body, which is achieved by the surface portions of the free-wheeling region having a distance from the axis of rotation of the coating roller smaller than the circular radius of the coating region formed as a circular cylinder segment. Preferably, the free-wheeling region is defined by all surface portions of the free-wheeling region being spaced from the axis of rotation of the coating roller by a distance smaller than the radius of the coating area.
The free-wheeling region serves in particular to enable a transport movement for the cylindrical hollow body, which is achieved by a rotary step movement of the workpiece rotary table relative to the machine frame, without any undesired contact between the coating roller and the outer surface of the cylindrical hollow body. Such an unwanted contact could lead to an uncontrolled application of coating to the outer surface of the cylindrical hollow body and/or to a disproportionate wear of the coating roller. As an example, the coating roller is designed with a constant profiling along its axis of rotation, in which the coating area in a cross-sectional plane aligned transversely to the axis of rotation corresponds to a circular arc section aligned concentrically to the axis of rotation and the free-wheeling region has a radial extension relative to the axis of rotation of the coating roller which is smaller than a radius of the coating area.
The rotary step movement of the workpiece rotary table typically comprises a sequence of acceleration of the workpiece rotary table from a rest state (in a coating position for at least one hollow body relative to the coating station) to a predeterminable maximum rotational speed and subsequent deceleration of the workpiece rotary table to a subsequent rest state, whereby at least one further (subsequent) hollow body is brought into the coating position relative to the coating station, and a predeterminable holding period which can be maintained during the rest state for carrying out the coating operation.
Provided that the rotary step movement is synchronized in a suitable manner with a—preferably provided—permanent rotation of the coating roller about the axis of rotation, it can be ensured that during the rotary step movement of the workpiece rotary table the coating roller is aligned with its free-wheeling region opposite to a plane of movement described by the cylindrical hollow bodies, so that no undesired contact occurs between the cylindrical hollow bodies and the coating roller independently of the rotary position of the workpiece rotary table.
Advantageous further embodiments of the invention are subject of the subclaims.
It is useful if the rotary axes of the mandrels and the rotary axis of the coating roller are aligned transversely to the rotary axis of the workpiece rotary table. The outer surfaces of the cylindrical hollow bodies thus determine a circular disk-shaped plane of motion, which is characterized by the fact that it represents the minimum distance of the outer surfaces of the cylindrical hollow bodies from the coating station, in particular from the axis of rotation of the coating roller. This minimum distance is dimensioned in such a way that it corresponds to the circular radius of the coating area of the coating roller, which is designed as a circular cylinder segment, with the exception of a coating gap dependent on the coating to be applied and the elasticity properties of the cylindrical hollow body and the coating roller, in particular the coating gap. This ensures an advantageous contact, in particular a line contact, between the hollow body and the coating area. A central axis of the circular movement plane is identical to the rotational axis of the workpiece rotary table. This makes it possible to achieve a favourable compromise with regard to the supply and discharge of cylindrical hollow bodies in the radial direction onto the holding mandrels or from the holding mandrels and a compact arrangement of at least one coating station on the machine frame opposite the workpiece rotary table.
In a further configuration of the invention, it is provided that holding mandrels arranged in pairs adjacent each other on the workpiece rotary table which are aligned parallel to each other and that the coating station comprises two coating rollers aligned parallel to each other, each of the coating rollers being aligned opposite one of the two holding mandrels in a coating position of the workpiece rotary table. The parallel alignment of the mandrels arranged adjacent to each other allows the cylindrical hollow bodies to be efficiently pushed onto the mandrels to be efficiently and pulled off from the mandrels respectively. Furthermore, the outer surfaces of the cylindrical hollow bodies can be machined at different work stations in a circumferential direction along a circular movement path for the cylindrical hollow bodies which is determined by the rotary step movement of the workpiece rotary table as well as a feed device for the cylindrical hollow bodies and a discharge device for the cylindrical hollow bodies. The arrangement of the two coating rollers of the coating station opposite each other to the holding mandrels arranged in pairs and aligned parallel to each other applies to the coating position of the workpiece rotary table during a holding period in which no rotational movement of the workpiece rotary table takes place. During this holding period, the outer surfaces of two cylindrical hollow bodies can be coated at the coating station with two coating rollers arranged opposite each other. It is particularly preferred that rotational movements of the parallel mandrels and thus also rotational movements of the parallel coating rollers are aligned in opposite directions. This allows an advantageous, in particular mirror-symmetrical, application of force from the coating rollers to the workpiece holders of the workpiece rotary table. Preferably, at least force components of the forces occurring when the respective coating areas of the coating rollers impinge on the associated outer surfaces of the hollow bodies are aligned mirror-symmetrically with respect to one another so that, at least with respect to these force components, a cumulative force on the workpiece rotary table disappears.
In the case of an advantageous further embodiment of the invention a distance between the axis of rotation of the mandrels arranged in pairs is smaller than a distance between the axis of rotation of the coating rollers aligned parallel to each other. The task of the coating rollers is usually to achieve a complete circumferential coating of the outer surface of the cylindrical hollow bodies. Accordingly, due to the segmentation of the circumferential surface of the coating roller into the coating area and the free-wheeling region, a length of an arc determined by the coating area must be at least equal to the circumference of the outer surface of the cylindrical hollow body. As a result, an envelope curve determined by the coating area around the respective coating roll, which is swept during rotation of the coating roll, must have a larger diameter than the cylindrical hollow body, so that the axes of rotation of the coating rolls aligned parallel to each other must have a distance that is bigger than a distance between the holding mandrels arranged in pairs.
It is preferred that the coating area of the coating roller covers an angular range of less than 270 degrees, preferably less than 240 degrees, especially preferred less than 210 degrees, especially less than 180 degrees. The coating area has to be matched to the outer surface of cylindrical hollow bodies in such a way that a complete circumferential coating of the outer surface of the cylindrical hollow body can be ensured by the coating roller. Furthermore, it is advantageous if a rotational speed of the coating roller can be kept as low as possible in order to allow as low centrifugal forces as possible to act on the coating absorbed at the coating area. Accordingly, it is advantageous if the circular radius of the coating area designed as a circular cylinder segment is as large as possible and only a small angular range relative to the axis of rotation of the coating roller is occupied by the coating area in order to carry out the rolling movement on the outer surface of the cylindrical hollow body.
It is advantageous if a length of a circular arc determined by the coating region is bigger, preferably at least 10 percent bigger, preferably at least 20 percent bigger, particularly preferably at least 30 percent bigger, in particular at least 40 percent bigger, than a circumference of the holding mandrel. Here it is assumed that an outer diameter of the cylindrical hollow body is only slightly larger than a diameter of the holding mandrel, in particular in the range of less than 1/10 mm, so that the circumference of the holding mandrel almost corresponds to the circumference of the outer surface of the cylindrical hollow body. Due to the fact that the circumference of the coating region is larger than the circumference of the outer surface of the cylindrical hollow body a preferably homogeneous application of the coating to the outer surface of the cylindrical hollow body is achieved.
The invention also provides for the coating roller to be rotatably mounted on the machine frame at a first end area and fixedly coupled to a rotary drive at a second end area. This bearing of the coating roller on both sides favours an advantageous support of the coating roller with regard to the reaction forces which can occur during the coating of cylindrical hollow bodies. This also facilitates the adjustment of a spatial position of the axis of rotation of the coating roller relative to the axis of rotation of the associated mandrel, since the two-sided bearing of the coating roller at the end area facing away from each other along the axis of rotation ensures a stable support for the coating roller. The coating roller is mounted on the machine frame via the coating station fixed to the machine frame, so that a force flow is transferred from the coating roller via the coating station into the machine frame.
It is preferably provided that a cylindrical receiving shaft is formed at the coating station, in which receiving shaft an eccentric sleeve is rotatably accommodated, wherein the rotary drive is accommodated in the eccentric sleeve and the eccentric sleeve may be coupled non-rotatably to the coating station. By receiving the rotary drive, which is preferably provided with a circular cylindrical housing, in the eccentric sleeve, whose bore for receiving the rotary drive has a central axis which does not coincide with a central axis of an outer surface of the eccentric sleeve, an advantageous and sensitive setting of an axial distance for the rotational axis of the rotary drive and the coating roller coupled thereto relative to the rotational axis of the holding mandrel can be ensured in the coating position. In particular, an adjusting equipment is provided for this purpose which is coupled to the eccentric sleeve and to the coating station and is designed for adjusting a rotational position of the eccentric sleeve relative to the coating station.
It is expedient when a cylindrical coating roller which is rotatably mounted at the coating station and is designed for a rolling movement on the coating region of the coating roller is arranged parallel to the coating roller, a coating tank for continuous coating application to the coating roller being assigned to the coating roller. The task of the coating roller is to apply a liquid coating (in particular a radiation, preferably ultraviolet radiation, hardenable coating) as uniformly as possible to the coating area of the coating roller. The coating is stored in the coating tank (which is also referred to as a blade unit) so that the outer surface of the cylindrical hollow body touched by the coating area of the coating roller during the coating process can also be coated as evenly as possible with a constant layer thickness of the coating. As an example, it is provided that the coating roller, which is also referred to as an anilox roller, has an outer surface made of a hard material such as steel or ceramic, in which a multiplicity of small depressions, which are also referred to as anilox depressions, are made, these depressions serving to transport the coating from the coating tank to the coating region of the coating roller. Preferably at least one blade-like scraper strip (squeegee) is provided in the coating tank, which, when the coating roller rotates, strokes over the outer surface of the coating roller and removes the excess coating from the outer surface of the coating roller. Only the coating deposited in the recesses remains on the outer surface of the coating roller, which can be rolled off on the coating area of the coating roller.
In a further configuration of the invention, a further coating station is provided which comprises at least one ink-jet print head which is designed for a freely predeterminable coating of a surface region of a cylindrical hollow body accommodated on a holding mandrel. While the coating region of the coating roller is designed for a uniform paint application or coating application, in particular on the entire outer surface of the cylindrical hollow body, the at least one ink jet print head serves for an individual, freely predeterminable coating, in particular printing, of a surface region of the cylindrical hollow body. It is preferably provided that one or more coating stations equipped with ink jet print heads are arranged on the machine frame of the coating apparatus, which coating stations enable coating, in particular printing, of the outer surface of the cylindrical hollow body with different motifs in different colours.
It is preferably provided that the coating roller has a dimensionally stable, preferably cylindrical, carrier shaft on the outer surface of which an elastic layer is applied, the circumferential surface of which determines the coating region and the free-wheeling region. As an example, the carrier shaft is produced from a metal material or a fibre-reinforced plastic material and provided with a rubber-elastic coating, in particular from the material group EPDM (ethylene-propylene-diene rubber), wherein a material-locking coupling of the elastic layer to the carrier shaft is provided.
It is advantageous if the carrier shaft is penetrated by a longitudinal bore which in each case has a conical shaped widening at each end, in particular extending up to an end face of the carrier shaft. The task of the end widenings is to enable a positive, self-centering coupling with correspondingly designed guide cones which are rotatably mounted at the coating station. An example of this is that one of the guide cones is mounted on the coating station so as to be freely rotatable, while the other guide cone represents an end section of a drive shaft of a rotary drive associated with the coating station. It is advantageous if at least one of the guide cones can be displaced linearly along the axis of rotation for the coating roller to allow insertion or removal of the coating roller in an open position and to allow the desired centring, torque transmission and power transmission between the drive shaft and the coating roller in a functional position.
It is advantageous if a positioning equipment designed as a projection or recess for a torque proof coupling with a drive shaft of a rotary drive is formed on the carrier shaft, in particular in the area of the widening. The positioning equipment can be used in a double function for the (rotationally) correct positioning of the coating roller relative to the drive shaft of the rotary drive. In addition, the positioning equipment can provide at least one surface which is used for torque transmission between the drive shaft of the rotary drive and the carrier shaft and whose surface normal is preferably aligned at least substantially perpendicularly to the axis of rotation of the coating roller. As an example, it can be provided that the positioning equipment is formed as a recess in the region of the widening on the carrier shaft and a corresponding projection is provided on at least one of the guiding cones in order to ensure the desired positioning of the coating roller and the transmission of force and torque between the coating roller, the coating station and the machine frame.
The task of the invention is solved by a process for coating cylindrical hollow bodies. The method comprises the following steps: Carrying out a rotary step movement of a workpiece rotary table with respect to a machine frame to provide a hollow body, which is accommodated on a mandrel, in a coating position opposite to a coating roller and maintaining the coating position for a predeterminable holding period, carrying out a rolling movement of a coating region of the coating roller relative to the rotating hollow body during the holding period, the rolling movement of the coating region of the coating roller relative to the rotating hollow body taking place during a coating period which forms a subset of the holding period. For an advantageous application of a coating to the outer surface of the cylindrical hollow body, a slip-free rolling movement of the coating area of the coating roller relative to the hollow body is desirable. Accordingly, it is provided on the one hand that the hollow body is set into a uniform rotational movement at least immediately before the start of the coating process, a peripheral speed of the rotating hollow body being adapted to a peripheral speed of the coating region of the coating roller, in particular being identical. Furthermore, the coating time period, i.e. the time period within which there is contact between the coating region of the coating roller and the rotating hollow body, is shorter than a holding time period within which the workpiece rotary table does not carry out a rotary step movement but is rather based relative to the machine frame, the hollow body being in the coating position relative to the coating station. Furthermore, in order to avoid undesirable relative movements between the coating roller and the hollow body, it is provided that the coating time span is completely included within the holding time span and thereby forms a partial or subset of the holding time span, the contact between the coating area and the hollow body taking place exclusively during the coating time span.
For example, it can be assumed that a holding time of 1 second is provided from a standstill time of a previous rotary step movement of the workpiece rotary table to an acceleration time of a subsequent rotary step movement of the workpiece rotary table. Within this holding time span, for example, the coating time span can be 0.6 seconds and starts 0.2 seconds after the start of the holding time span and ends 0.2 seconds before the end of the holding time span. This ensures that 0.2 seconds elapse between the time the workpiece rotary table comes to a standstill and the start of the coating process and 0.2 seconds elapse between the end of the coating process and the re-acceleration of the workpiece rotary table. For example, the duration of the rotary step movement, within which the freshly coated hollow body is removed and an uncoated hollow body is provided to the coating station, is also 1 second.
An advantageous form of the invention is shown in the drawing. Here shows:
A coating apparatus 1 shown schematically in
As an example, it is provided that adjacent workpiece holders 4 are arranged in pairs in parallel so that two hollow bodies 6 can be provided and removed at work stations 8 and 18 respectively by a linear movement of a transport device 19 and 20 respectively. It is intended that the rotary axes 5 of the workpiece holders 4 should be at a distance of 22 from each other.
As an example, it is assumed that each of the workpiece holders 4 is assigned its own separately electrically controllable drive motor which is not shown and which enables the respective workpiece holder 4 to rotate about the respective axis of rotation 5. This possibility for, in particular, controlled rotation of the respective workpiece holder 4 is used in particular for carrying out the coating process and the coating process described in more detail below.
In an annular section-shaped region which is swept by the workpiece holders 4 during a rotary movement of the workpiece rotary table 3 about the axis of rotation 87, which can be named as movement path 7 and which extends in the circumferential direction around the workpiece rotary table 3, a plurality of work stations 8 to 18 are arranged which are designed for machining and/or inspecting the transported hollow bodies 6. Since the view shown in
The work station 8 is a loading station also referred to as a feed station, at which the cylindrical hollow bodies 6 are pushed in pairs onto the workpiece holders 4 by a suitable transport device 19, which is coupled with a conveyor system for the cylindrical objects 6 which is not shown in detail.
At workstation 9, a purely exemplary neutralization of electrical charges is planned, which may be present at an outer surface 25 of the hollow body 6. Such a neutralization is particularly advantageous for hollow bodies 6 made of plastic and may be omitted for hollow bodies 6 made of metal. For the electrical (electrostatic) neutralisation of the hollow bodies 6, the work station 9 comprises a neutralisation arrangement which is not described in detail and with which the discharge of the hollow body 6 can be carried out. As an example, the neutralisation arrangement comprises two electrodes arranged at a distance from one another, to each of which an alternating electric field is applied by a control device which is also not shown in detail. An electric voltage and a frequency of the electric alternating field are matched to the distance between the electrodes in such a way that gas, in particular air, present in the vicinity of the electrodes can be ionised. With the help of the released ions, a charge balance can take place with the electrical charges present on the outer surface 25 of the hollow body 6. The now electrically neutral hollow body 6 is then conveyed along the movement path 7 to the following work station 10.
Downstream along the movement path 7, the work station 10 is provided subsequent to the work station 9, which is purely exemplarily a cleaning arrangement. As an example, the cleaning station is designed as a suction device which is designed for contactless suction of the outer surface 25 of the hollow body 6.
An optical scanning of the cylindrical hollow bodies 6 takes place purely exemplarily at the work station 11 arranged downstream along the movement path 7 to the work station 10 in order to determine a rotational position of the cylindrical hollow bodies 6, for example in order to ensure a correct rotational alignment of the cylindrical hollow bodies 6 for a coating process taking place at the work station 12, in particular a printing process, i.e. a local coating of the hollow body 6 with a predetermined decoration and/or a predetermined inscription. This is particularly important if the outer surface of the hollow body 6 to be coated is provided with features which are to fit in a predetermined manner with a printed image to be applied during this coating. These features may be, for example, a local embossing and/or an embossing into and/or from the outer surface of the hollow body 6 and/or pre-printed areas which in turn are to serve as a primer for the subsequent coating.
The hollow body 6 is now moved in the course of a further rotary step movement of the workpiece rotary table 3 around the rotation axis 87 one after the other to the work stations 12, 13 and 14, which are each designed purely exemplarily as coating stations in order to be coated, in particular printed, there with the aid of coating apparatuses 51, as they are exemplarily shown in
The work station 15 arranged downstream of the work station 14 along the movement path 7 is exemplarily designed as an inspection device and makes it possible to determine the coating quality of the printed image applied by the coating station 21 to the circumferential surface of the hollow body 6.
The further work station 16 serves for the further processing of the cylindrical hollow bodies 6 by applying a protective coating to the coating at least on partial surfaces of the hollow body 6. Preferably it is intended that an entire, circular cylindrical outer surface of the respective hollow body 6 is provided with a protective coating.
The following work station 17 has a radiation source (not shown) which is designed for curing the protective coating applied at the work station 16. Preferably, this is a radiation source for ultraviolet radiation.
At work station 18, an unloading process takes place during which the cylindrical hollow bodies 6 are removed from the mandrel-shaped workpiece holders 4 by means of a transport device 20 and fed to a further transport system which is not described in detail.
The workpiece rotary table 4 carries out a rotary step movement around the angle W for the stepwise machining of the cylindrical hollow bodies 6 at the respective work stations 8 to 18, in which the workpiece holders 4 arranged in pairs are transported from a position opposite the respective work stations 8 to 18 to a position opposite the respective subsequent work stations 8 to 18. The rotary step movement takes place as a sequence of acceleration from a standstill, deceleration from the target speed reached and a subsequent holding period. Preferably, an drive (not shown) for the workpiece rotary table 3 is designed in such a way that the acceleration and deceleration of the workpiece rotary table 3 can be freely adjusted over a wide range and the holding time can be adapted to the requirements of the machining of the respective cylindrical hollow bodies 6 at the work stations 8 to 18.
As can be seen from
The coating rollers 47 and 48 each have a circumferential surface 73, 74, which is drawn in dashed form in the illustration of
The two coating rollers 47, 48 are arranged on the carrier frame 40 in such a way that their axes of rotation 59, 60 each have an identical distance 83 to a plane of movement 84. The movement plane 84 is determined by the outer surfaces 85, 86 of the hollow body 6 by its pivoting movement about the axis of rotation 87 of the workpiece rotary table shown in
The distance 83 is dimensioned in such a way that the two coating rollers 47, 48 do not intersect the plane of movement 84 at least over a partial area of their respective free-wheeling regions 79, 80, so that the pivoting movement of the hollow bodies 6 about the axis of rotation 87 can be carried out in the plane of movement 84 without contact taking place with the respective coating rollers 47, 48 in this case.
On the other hand, in the rest position of the workpiece rotary table, which corresponds to a coating position for the hollow bodies 6 opposite the coating rollers 47, 48 which is not shown in more detail, a contact between the respective coating area 75, 76 and the outer surface 85, 86 of the respective hollow body is possible by a respective counter-rotating rotational movement of the hollow body 6 and the associated coating roller 47, 48. With this contact, which takes place during a rolling movement that is as slip-free as possible (synonymous with identical and uniform circumferential speeds for the hollow bodies 6 and the respective coating rollers 47, 48), a coating is applied to the outer surface 85, 86 of the respective hollow body 6.
In particular, it is provided that a length of a circular arc 88, 89 determined by the respective coating area 75, 76 is bigger than a circumference of the respective outer surface 85, 86 of the hollow body 6, so that complete wetting of the outer surface 85, 86 of the hollow body 6 with the coating can take place, which coating can be provided by the respective coating roller 47, 48 in the respective coating area 75, 76.
For the supply of the coating with the help of the respective coating rollers 47, 48, each of the coating rollers 47, 48 is assigned a coating transfer roller 90, 91, which is also referred to as an anilox roller and which is accommodated in a coating tank 92, 93, which is filled with liquid coating in an unspecified manner, in each case area and in rotation. The task of the coating transfer roller 90, 91 is to apply the liquid coating present in the coating tank 92, 93 to the coating area 75, 76 of the respective coating roller 47, 48. For this purpose, blade-like doctor blades are arranged in the coating tank 92, 93, which are not shown in detail, which wipe off the excess coating from the surface of the respective coating transfer roller 90, 91 and thus ensure a transfer of an exactly predeterminable coating quantity from the respective coating transfer roller 90, 91 to the assigned coating roller 47, 48.
In order to prevent the coating transfer rollers 90, 91 and the associated coating rollers 47, 48 from drying out, it is preferably provided that the coating transfer rollers 90, 91 and the coating rollers 47, 48 rotate permanently, in particular at constant circumferential speeds, in deviation from the intermittent rotary step movement of the workpiece rotary table. A synchronization of these rotary movements for the coating rollers 47, 48 with the hollow bodies 6 provided in the course of the rotary step movement of the workpiece rotary table in the coating position not described in more detail below, described in more detail, enables the desired coating application to the outer surface 85, 86 of the hollow bodies 6.
As an example, it is provided that a holding period for the rotary step movement of the workpiece rotary table about the axis of rotation 87 is so dimensioned that during this rest phase of the workpiece rotary table a complete and in particular slip-free rolling movement of the respective coating areas 75, 76 on the outer surfaces 85, 86 of the hollow body 6 can take place. Accordingly, a coating time span for the contact between the coating areas 75, 76 and the outer surfaces 85, 86 is smaller than the holding time span and is completely included in the holding time span.
It is preferably provided that during a rotary step movement for the workpiece rotary table 3, within each of which two hollow bodies 6 are conveyed into the sphere of influence of the coating station 16 and removed again from the sphere of influence of the coating station 16, the rotary step movement of the workpiece rotary table comes to a standstill and this period of the standstill is referred to as the holding period. During this holding period, the outer surfaces 85, 86 of the hollow bodies 6 are coated.
With respect to the preferably constant rotation of the respective coating rollers 47, 48 about the rotation axes 59, 60, the coating time span can be represented by the angle 94 and the holding time span by the angle 95, while the angles 96 and 97 represent the feed of the hollow bodies 6 during the rotary step movement before the holding time span and the removal of the hollow bodies 6 during the rotary step movement after the holding time span, respectively.
Accordingly,
As soon as the hollow bodies 6 have reached the coating position which is not shown closer, symmetrically to the axis of rotation 87, the holding period represented by the angle 95 begins, within which the coating period represented by the angle 94 is then included, the contact between the coating areas 75 and 76 with respect to the hollow bodies 6 taking place exclusively during the coating period.
The structure and geometry of the coating roller 47 (and in the same way the coating roller 48) are shown in
The carrier shaft 100 is interspersed with a rotationally symmetrical longitudinal bore 103, which has a first diameter of 104 in a central area and a second diameter of 105 adjacent and stepped to it at the ends, each of which defines a cylinder bore section 106. The cylinder bore section 106 is adjoined at each end by a conical section-shaped widening 109, 110 which extends to an end face 107, 108. In the widening 109 two oppositely arranged recesses 111 and 112 are formed as examples, which have a different width according to the illustration in
The widening 110 arranged at the opposite end face 108 is preferably exclusively cone-shaped and is intended for planar contact with a bearing cone 116, which is mounted on the carrier frame 40 in a rotationally movable manner and is shown only schematically in
| Number | Date | Country | Kind |
|---|---|---|---|
| 18161893 | Mar 2018 | EP | regional |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2015669 | Gravely | Oct 1935 | A |
| 3630140 | Marrie | Dec 1971 | A |
| Number | Date | Country |
|---|---|---|
| 2868477 | May 2015 | EP |
| 3088090 | Nov 2016 | EP |
| 3156242 | Apr 2017 | EP |
| Number | Date | Country | |
|---|---|---|---|
| 20190283068 A1 | Sep 2019 | US |
