Arrangement for surface treatment and use of this arrangement

Abstract

Arrangement for surface treatment of at least one workpiece (2), comprising a workpiece carrier (1) supporting the at least one workpiece (2), which in turn is rotatably mounted within a treatment zone (10) about a predetermined axis of rotation (20) arranged therein, wherein at least one drive (16) for rotating or pivoting the workpiece carrier (1) about said axis of rotation (20) is arranged outside the treatment zone (10), which in turn is operatively connected to the workpiece carrier (1), characterized in that the at least one drive (16) for rotating or pivoting the workpiece carrier (1) is formed by a linear drive, which in turn is fixedly arranged outside the treatment zone (10) and is detachably operatively connected to the workpiece carrier (1), wherein the workpiece carrier (1) has two axially opposite upper second pins (9) or extensions (21) pointing in opposite directions.each of which is assigned a receiving means (17) that can be moved by means of at least one drive (16) and which in turn is positively connected or connectable to the associated upper second pin (9) or the boom (21).

Description

[0001] The invention relates to an arrangement for the surface treatment of at least one workpiece, comprising a workpiece carrier carrying the at least one workpiece, which in turn is rotatably mounted within a treatment zone about a predetermined axis of rotation arranged therein, wherein at least one drive is arranged outside the treatment zone, which drive is in turn connected to the workpiece carrier.

[0002] When treating the surfaces of workpieces with a geometry that creates cavities or treatment shadows, there is the problem that not all surfaces of the workpiece can be treated in a fixed position. For example, when dipping or spraying a workpiece with cavities, air and / or gas bubbles cannot escape and surfaces located in the treatment shadow cannot be treated. In areas with air and / or gas bubbles or treatment shadows, surface treatment such as degreasing, phosphating, paint / KTL / ATL coating (KTL = cathodic dip painting; ATL = anodic dip painting), galvanic coating, etc. is usually not possible or only inadequate. In order to now treat areas of the workpiece with air and / or gas bubbles orTo adequately treat the area with treatment shadows, the workpiece is pivoted (inclined, tilted, rotated), which shifts / relocates the air / gas bubbles in the cavity or the treatment shadow in question, making these areas treatable. Surface treatment arrangements that specifically address the above-mentioned problem and allow pivoting of the workpiece have been known for some time in a wide variety of designs.

[0003] For example, DE 2 032 828 A1 discloses a perforated container for holding metal parts for surface treatment in liquid baths. The container is suspended in a tank filled with said liquid and surrounded by the liquid. The container is supported by support beams of a conventional gantry conveyor system and is rotatably mounted on said support beams by means of a chain drive with a drive chain and sprockets, as well as a gear drive.

[0004] DE 29 04 176 A1 also discloses a method and device for preserving workpieces by dipping them into a dip tank. This method also includes a gantry conveyor unit comprising two parallel, horizontal support rails mounted on supports, along which a carriage is movable by rollers and driven by electric motors. Connected to the carriage are two vertical holders with cardanic joints, the rotational axes of which form the common rotational axis of two gripping devices carrying a workpiece. A drive allows the holders, including the workpiece, to be lowered into a dip tank. An electric motor attached to a holder, which in turn is connected to a gripping device, allows the workpiece to be rotated during coating.

[0005] EP 0 146 437 A1 also discloses a gantry conveyor unit with a workpiece carrier suspended therefrom, which, in turn, can be lowered into a container filled with a corresponding treatment fluid for electrophoretic coating of a workpiece. By means of a crank drive, which in turn is operatively connected to a gear wheel of the workpiece carrier via a rack, the workpiece carrier, including the workpiece, can be rotated about a horizontal axis of rotation within the treatment fluid. Furthermore, this document proposes pivotally suspending the workpiece carrier from the gantry conveyor unit.

[0006] Furthermore, DE 40 33 333 A1 discloses a surface treatment device comprising a workpiece carrier suspended from a conventional industrial truck by means of ropes and chains, which, in turn, can be lowered together with a workpiece into a container filled with a treatment bath. The workpiece carrier is rotatable about a predetermined axis of rotation and has a pinion at each end of the axis of rotation. When the workpiece carrier is lowered, this pinion engages a guide frame with a rack attached to the container. This pinion is set in rotation both during the lowering and the subsequent lifting.

[0007] The aforementioned arrangements of this type have in common the use of relatively complex rotating or pivoting devices, which, on the one hand, are attached to or supported on the industrial truck and are therefore regularly transported together with the workpiece carrier. On the other hand, individual parts or bearing components of the rotating or pivoting devices are directly exposed to the treatment bath, or at least located in the immediate vicinity of it, and therefore require a correspondingly complex design and protection against adverse effects from the treatment bath.

[0008] From JP 57174500 A, a workpiece carrier is known which in turn is rotatably mounted on a frame arranged within a container filled with a treatment bath and is rotatably driven by means of a crank drive, wherein rotating bearing parts of the crank drive are disadvantageously arranged within the treatment bath.

[0009] DE 100 47 968 ​​A1 discloses a system for surface treatment of workpieces, which comprises several bogies that can be individually moved to treatment stations. Each bogie has a holder for a workpiece. By rotating about a rotation axis, the holder together with the workpiece can be introduced into the treatment station. Each bogie has its own drive for moving it along a guide device, which drive is designed in the manner of a linear drive, a revolving cable, or a revolving chain. A lever system can be provided for rotating the holder together with the workpiece. However, a rotary drive provided on the bogie is preferred for this purpose. Furthermore, according to this document, a common drive can also be provided for movement and for carrying out the rotation.

[0010] WO 2009 / 083081 A1 discloses a so-called dip treatment system with a dip tank and a conveyor system for objects to be painted. The conveyor system comprises a transport carriage on which a movable carriage is mounted. A component defining a rotational axis is mounted on the movable carriage, which has a fastening device for the object to be treated. A movement sequence for the object can be achieved that is a superposition of a horizontal linear movement, a vertical linear movement, and a rotational movement about the rotational axis. The horizontal linear movement, the vertical linear movement, and the rotational movement are driven by an electric motor.

[0011] The object of the invention is to create an alternative arrangement for the surface treatment of at least one workpiece with regard to the generic prior art, which allows for a largely complete surface treatment of the workpiece to be treated with minimal technical effort. In particular, said arrangement is intended to ensure that the geometry of a workpiece, which has cavities and / or treatment shadows during the initial surface treatment, receives sufficient surface treatment without defects.

[0012] Starting from an arrangement for the surface treatment of at least one workpiece with a workpiece carrier carrying the at least one workpiece, which in turn is rotatably mounted within a treatment zone about a predetermined axis of rotation arranged therein, wherein outside the treatment zone at least one drive for rotating or pivoting the workpiece carrier about said axis of rotation is arranged, which in turn is operatively connected to the workpiece carrier, the stated object is achieved in that the at least one drive for rotating or pivoting the workpiece carrier (1) is formed by a linear drive, which in turn is arranged stationary outside the treatment zone and is detachably operatively connected to the workpiece carrier, wherein the workpiece carrier has two axially oppositely arranged and oppositely directed upper second pins or arms,each of which is assigned a receiving means which can be displaced by means of the at least one drive and which in turn is or can be connected in a form-fitting manner to the associated upper second pin or the boom.

[0013] This simple and cost-effective measure, namely the provision of a linear drive, for example, pneumatically, hydraulically, electrically, or electromagnetically operated, which is itself stationary outside the treatment zone and thus protected from any potentially harmful effects of the treatment medium used, allows the workpiece carrier, along with at least one workpiece carried by it, to pivot within the treatment zone with minimal technical effort. It is ensured that even surfaces within cavities of the at least one workpiece, or surfaces of the workpiece that lie in the treatment shadow after the original treatment process, receive sufficient surface treatment without defects.

[0014] The subclaims describe preferred developments or embodiments of the invention.

[0015] According to a preferred embodiment of the invention, the treatment zone can be arranged within a container that is at least temporarily open at the top, and the workpiece carrier can have two lower first pins arranged axially opposite one another and pointing in opposite directions within the predetermined axis of rotation, by means of which the workpiece carrier is mounted rotatably within an associated vertically aligned groove-shaped receiving and guiding pocket in the container wall and vertically displaceably along the respective receiving and guiding pocket, wherein the groove-shaped receiving and guiding pockets are provided on the inner or outer surface of the container wall. Such mounting of the workpiece carrier within the container is extremely simple and cost-effective to achieve.The workpiece carrier can further comprise two upper second pins or arms arranged axially opposite one another and pointing in opposite directions, each of which is assigned a receiving means displaceable by means of the at least one drive, which in turn is positively connected or connectable to the associated upper second pin or arm. This advantageous measure permits simple actuation of the workpiece carrier in the sense of a pivoting movement about said axis of rotation. Furthermore, it can be provided that the workpiece carrier is supported vertically on the container either by means of the upper second pins or arms via said receiving means or by means of the lower first pins within the vertically aligned groove-shaped receiving and guide pockets.According to a particularly practical embodiment of the invention, the receiving means can be displaceably guided along a respective adjacent upper container edge on or in a respective guideway. Furthermore, the guideways can be designed either horizontally and rectilinearly or curved in a vertical plane. In the latter case, it is advantageously possible to control the movement of the lower first pin of the workpiece carrier. Thus, curved guideways can advantageously prevent a vertical movement of the workpiece carrier that overlaps the pivoting movement of the workpiece carrier, provided that the workpiece carrier is vertically supported on the container by means of the upper second pin via said displaceable receiving means.As further provided by the invention, the groove-shaped receiving and guide pockets can either be designed as add-on parts and fixedly arranged on the inner or outer surface of the container wall, or they can be formed integrally with the container wall or molded into it. This allows the receiving and guide pockets to be individually adapted to the current operating conditions. Furthermore, said groove-shaped receiving and guide pockets can each have an upper, upwardly widening receiving section and a guide section adjoining the receiving section at the bottom, thereby simplifying the insertion of the lower first pins of the workpiece carrier into the receiving and guide pockets from above, for example by means of a crane system.Finally, the groove-shaped receiving and guiding pockets can themselves be electrically insulated or electrically insulated from the container wall, which is particularly suitable for the well-known KTL dip painting process, also known as cathodic dip painting or cathodic electrocoating. In this type of electrochemical painting process, the workpiece to be painted is immersed in an electrically conductive, aqueous dip paint, and a DC voltage field is applied between the workpiece and a counter electrode.

[0016] The invention also relates to the use of an arrangement of the type described above for degreasing, phosphating, KTL coating (KTL = cathodic dip painting), ATL coating (ATL = anodic dip painting), rinsing, spraying, spray rinsing, blasting, galvanic treatment or coating, pickling and passivating, painting and / or for another known surface treatment of the at least one workpiece.

[0017] The invention is explained in more detail below with reference to the exemplary embodiments schematically illustrated in the drawings. They show: Fig. 1 the perspective view of a workpiece carrier of the inventive arrangement for surface treatment, Fig. 2 the arrangement for surface treatment in a sectional view according to a first embodiment, with a workpiece carrier according to Fig. 1 and with a container filled with a treatment liquid and designed to pivot the workpiece carrier, into which the workpiece carrier is inserted, Fig. 3 the arrangement for surface treatment in a view along the section line “II” according to Fig. 2, where three operating positions of a receiving means of a swivel drive connected to the workpiece carrier are shown very schematically, Fig. 4 the arrangement for surface treatment according to Fig. 3 supplemented by two operating positions (initial position and swivel position) of the workpiece carrier, Fig. 5 based on the execution according to Fig. 3 shows a second embodiment of the arrangement for surface treatment Fig. 6 the arrangement according to Fig. 5 supplemented by two operating positions (initial position and swivel position) of the workpiece carrier, Fig. 7 the arrangement for surface treatment in a sectional view according to a third embodiment, and Fig. 8 the arrangement for surface treatment in a sectional view according to a fourth embodiment, with a workpiece carrier according to Fig. 1 and with a frame designed for pivoting the workpiece carrier, into which the workpiece carrier is inserted and which is arranged within a treatment cabin.

[0018] Fig. 1 initially shows a workpiece carrier 1 in which a plurality of workpieces 2, in this case a plurality of vehicle axles, are arranged. The workpiece carrier 1 is formed, for example, by a cuboid frame, which in turn has first laterally oppositely arranged struts 3 with, in this case, laterally positioned holding means 4, which serve to attach the workpiece carrier 1 to a known industrial truck 5, such as a crane system, which is therefore not shown in detail.

[0019] Furthermore, the workpiece carrier 1 has second struts 6 arranged laterally opposite one another below the first lateral struts 3, each with a lower first pin 7 positioned at the opposite side. Said lower first pins 7 are arranged axially relative to one another and point in opposite directions. In the present case, the lower pins 7 are formed as separate components. Alternatively, the lower first pins 7 can also be formed integrally by an axis extending transversely through the workpiece carrier 1 and projecting laterally (not shown in detail).

[0020] Between the struts 3 and 6 or the holding means 4 and the lower first pin 7, third struts 8 of the workpiece carrier 1 are provided, which are arranged laterally opposite one another and each have a set-off upper second pin 9. The upper second pins 9 are also arranged axially to one another and point in opposite directions. The pins 7 and 9 are preferably arranged in a common vertical plane and serve to support the workpiece carrier 1 in a container 11 having or forming a treatment zone 10 and which is open at the top (cf. in particular Fig. 2).

[0021] The workpiece carrier 1 and the container 11 form the arrangement for the surface treatment of the workpieces 2, for example, an arrangement for the known KTL dip painting, also referred to as cathodic dip painting or cathodic electrocoating. In such an electrochemical painting process, as already explained in the introduction, the workpieces 2 to be painted are immersed in a treatment bath in the form of an electrically conductive, aqueous dip paint (treatment zone 10), with a DC voltage field being applied between the workpieces 2 to be painted and a counter electrode (not shown in detail).

[0022] As in particular the Fig. 2 to 4, the workpiece carrier 1 together with the workpieces 2 is lowered from above into the container 11 by means of the said floor conveyor 5, which engages the holding means 4, and is further immersed into the treatment zone 10 or into the treatment bath, preferably to such an extent that the workpieces 2 are completely below the bath level 12 of the treatment bath.

[0023] As the workpiece carrier 1 is lowered into the container 11, the lower first pins 7 are each inserted into a corresponding elongated, groove-shaped receiving and guiding pocket 13, which extends vertically and is provided on the inner surface 14 of the container wall 15. At the same time, the upper second pins 9 are each positively deposited outside the treatment zone 10 or the treatment bath on a receiving means 17 that can be displaced by means of a drive 16.

[0024] In the present case, each receiving means 17 is assigned a separate drive 16 in the form of a linear drive, which in turn can be actuated pneumatically or hydraulically, for example. An electrically or electromagnetically actuated linear drive is also conceivable and is therefore encompassed by the invention. Furthermore, the receiving means 17 are each displaceably guided along an adjacent upper container edge 18 of the container 11 on or in a guide track 19, which in the present case is horizontal and rectilinear and has an L-shaped cross-section.

[0025] The groove-shaped receiving and guiding pockets 13 are designed here as separate attachments and are fixedly arranged on the inner surface 14 of the container wall 15, for example, firmly connected to the same by means of non-positive and / or materially bonded screw connections and / or by welding (not shown in detail). Alternatively, it may also be advisable to form the said groove-shaped receiving and guiding pockets 13 integrally with the container wall 15 by molding the groove-shaped receiving and guiding pockets 13 into the container wall 15 (not shown in detail).

[0026] Furthermore, the groove-shaped receiving and guide pockets 13 are in the present case U-shaped in cross-section and each have an upper receiving section 13a widening upwards and a guide section 13b adjoining the receiving section 13a downwards with largely constant dimensions.

[0027] Furthermore, with regard to the selected intended use of the arrangement according to the invention for surface treatment, namely the use thereof for KTL coating of the workpieces 2, the receiving and guide pockets 13 are themselves electrically insulated, for example provided by means of a known electrically insulating coating, or designed to be electrically insulated from the container wall 15 (not shown in detail).

[0028] The invention will be described below in particular with reference to Fig. 3 and Fig. 4 describes their function in more detail.

[0029] Assuming that a workpiece carrier 1 loaded with workpieces 2 is to be transported into the treatment bath of the container 11 by means of a conventional floor conveyor 5, the two lower first pins 7 are first threaded into the respectively associated receiving and guiding pocket 13, which is facilitated by their upwardly widened design. The workpiece carrier 1 can then be lowered vertically until the two upper second pins 9 are positively received by the respectively associated receiving means 17. In this state, the workpiece carrier 1 is supported by means of its upper second pins 9 indirectly via the receiving means 17 on the container wall 15 of the container 11 ( Fig. 3).

[0030] Are now in accordance with Fig. 4 the drives 16 or linear drives are activated, the workpiece carrier 1 performs a pivoting movement about a rotation axis 20, which in turn is arranged within the center axis of the lower first pin 7. Due to the rectilinear design of the guideways 19 of the receiving means 17, starting from a central basic position of the workpiece carrier 1 (cf. in particular Fig. 4) when pivoting, a vertical movement of the same is recorded, which is superimposed in the area of ​​the pins 7 with a rotational movement of the same.

[0031] If such a vertical movement is not desired, it is advisable to design the guideways 19 of the receiving means 17 curved within an imaginary vertical plane laid in the guideway 19, preferably as a circular arc, so that a fixed pivot point of the workpiece carrier 1 is achieved (not shown in detail). In order to subject cavities in the workpieces 2 or conventionally forming treatment shadows to sufficient surface treatment without defects, pivot angles "α" of the workpiece carrier 1 of approximately ± 10° have proven successful in tests.

[0032] The embodiment according to the Fig. 5 and Fig. 6 differs from the one described above essentially in that the workpiece carrier 1 is not supported vertically on the container 11 by means of its upper second pins 9 via said receiving means 17, but by means of the lower first pins 7 within a suitably designed bearing section 13c of the groove-shaped receiving and guide pockets 13. This measure brings about a fixed pivot point of the workpiece carrier 1 within the groove-shaped receiving and guide pockets 13, while the upper second pins 9 of the workpiece carrier 1 carry out a vertical relative movement within the respectively assigned receiving means 17 during pivoting operation of the same.

[0033] The above-described embodiments are based on a workpiece carrier 1, which in turn is pivotally mounted within the treatment zone 10 or the treatment bath. Such a mounting requires increased expenditure, for example, with regard to potentially aggressive treatment baths. Thus, it may prove necessary to manufacture, in particular, the lower first pins 7 of the workpiece carrier 1 and the groove-shaped receiving and guide pockets 13 from a correspondingly higher-quality steel alloy.

[0034] In order to avoid these increased expenses, it is advisable to Fig. 7, the bearing of the workpiece carrier 1 is to be mounted outside the container 11. In the present case, instead of the lower first pins 7, outriggers 21 are provided, which extend from the predetermined axis of rotation 20 of the workpiece carrier 1 over the container edge 18 of the container 11 into an associated groove-shaped receiving and guiding pocket 13, which is now provided on the outer surface 22 of the container wall 15. Here, too, the workpiece carrier 1 can be vertically supported on the container 11 via the receiving means 17 or via a bearing section 13c (not shown in detail here) of the groove-shaped receiving and guiding pocket 13. A horizontal section 21a of each outrigger 21 is positively received by the respectively associated receiving means 17.

[0035] Furthermore, the above embodiments are based on a container 11 with a treatment bath, in this case a dip coating. However, the arrangement according to the invention for the surface treatment of workpieces 2 is not limited to treatment baths, but also encompasses other measures for the surface treatment of workpieces 2, particularly of a spraying nature, such as spray painting, blasting, etc.

[0036] In this regard, according to Fig. 8, the treatment zone 10 is not provided in a container 11, but in a treatment cabin 23 known per se. The workpiece carrier 1 is pivotally mounted within a frame 24 of the cabin 23. In accordance with the first exemplary embodiment of the invention described above, the workpiece carrier 1 also has two first pins 7 arranged axially opposite one another within a predetermined axis of rotation 20 and pointing in opposite directions. The said axis of rotation 20 is arranged within the treatment zone 10. By means of the first pins 7, the workpiece carrier 1 is rotatably mounted within a vertically aligned groove-shaped receiving and guide pocket 13 of the said frame 24, each of which is assigned to the first pins 7, and is mounted so as to be vertically displaceable along the respective receiving and guide pocket 13.Outside the treatment zone 10, in this case on the frame 24 or in the immediate vicinity thereof, for example on the booth floor (not shown in detail), there are guided receiving means 17 driven by at least one drive 16 in the form of a linear drive, which in turn are operatively connected to the workpiece carrier 1 via second pins 9 and effect a pivoting movement of the workpiece carrier 1 within the frame 24 of the booth 23. As far as the vertical support of the workpiece carrier 1 on the frame 24 is concerned, this is achieved in this case by means of the second pins 9 indirectly via the receiving means 17.It may also be appropriate to provide, instead of said second pin 9, cantilevers 21 of the type already described above or to realize the vertical support of the workpiece carrier 1 on the frame 24 by means of the first pin 7 in a correspondingly designed bearing section 21a of the respective receiving and guide pocket 13, as has also already been proposed for the second embodiment and in the . Fig. 5 and Fig. 6 is shown. List of reference symbols 1 workpiece carrier 2 workpieces 3 first bracing 4 holding devices 5 Industrial trucks 6 second bracing 7 first cones 8 third bracing 9 second pins 10 Treatment zone / treatment bath 11 containers 12 bathroom mirrors 13 Receiving and guide pocket 13a Recording section 13b Guide section 13c storage section 14 Inner shell surface (container wall 15) 15 Container wall 16 Drive 17 recording devices 18 Container rim 19 Guideway 20 axis of rotation 21 booms 21a horizontal section (boom 21) 22 Outer shell surface (container wall 15) 23 treatment cabins 24 frame “α” swivel angle

Claims

[1] Arrangement for the surface treatment of at least one workpiece (2), with a workpiece carrier (1) carrying the at least one workpiece (2), which in turn is rotatably mounted within a treatment zone (10) about a predetermined axis of rotation (20) arranged therein, wherein outside the treatment zone (10) at least one drive (16) for rotating or pivoting the workpiece carrier (1) about said axis of rotation (20) is arranged, which in turn is operatively connected to the workpiece carrier (1), characterized byin that the at least one drive (16) for rotating or pivoting the workpiece carrier (1) is formed by a linear drive, which in turn is arranged in a stationary manner outside the treatment zone (10) and is detachably operatively connected to the workpiece carrier (1), wherein the workpiece carrier (1) has two upper second pins (9) or arms (21) arranged axially opposite one another and pointing in opposite directions, each of which is assigned a receiving means (17) which is displaceable by means of the at least one drive (16), which in turn is or can be connected in a form-fitting manner to the associated upper second pin (9) or the arm (21). [2] Arrangement according to claim 1, characterized byin that the treatment zone (10) is arranged within a container (11) which is at least temporarily open at the top, and the workpiece carrier (1) has, within the predetermined axis of rotation (20), two lower first pins (7) which are arranged axially opposite one another and point in opposite directions, by means of which the workpiece carrier (1) is mounted so as to be rotatable within a respective associated vertically aligned groove-shaped receiving and guiding pocket (13) of the container wall (15) and so as to be vertically displaceable along the respective receiving and guiding pocket (13), wherein the groove-shaped receiving and guiding pockets (13) are provided on the inner or outer circumferential surface (14, 22) of the container wall (15). [3] Arrangement according to claim 1 or 2, characterized bythat the workpiece carrier (1) is supported vertically on the container (11) either by means of the upper second pins (9) or the boom (21) on the receiving means (17) or by means of the lower first pins (7) within the vertically aligned groove-shaped receiving and guide pockets (13). [4] Arrangement according to claim 2 or 3, characterized by that the receiving means (17) are guided displaceably along a respective adjacent upper container edge (18) of the container (11) on or in a respective guide track (19) and the guide tracks (19) are either horizontal and rectilinear or curved in a vertical plane. [5] Arrangement according to one of claims 2 to 4, characterized bythat the groove-shaped receiving and guide pockets (13) are either designed as add-on parts and are fixedly arranged on the inner or outer surface (14, 22) of the container wall (15) or are designed in one piece with the container wall (15) or are formed into it. [6] Arrangement according to claim 5, characterized by that the groove-shaped receiving and guide pockets (13) each have an upper, upwardly widening receiving section (13a) and a guide section (13b) adjoining the receiving section (13a) downwards. [7] Arrangement according to one of claims 2 to 6, characterized by that the groove-shaped receiving and guide pockets (13) are themselves electrically insulated or are designed to be electrically insulated from the container wall (15). [8] Use of the arrangement according to one of claims 1 to 7 for degreasing, phosphating, KTL coating (KTL = cathodic dip painting), ATL coating (ATL = anodic dip painting), spraying, spray rinsing, blasting, galvanic treatment or coating, pickling, passivating and / or painting of the at least one workpiece (2).

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