Device for rotatably supporting section of shaft of roller of transport system, assembly, transport system and device for wet chemical treatment of workpieces

Abstract

A device for rotatably supporting a section of a shaft (4) of a roller (2) of a conveyor system in a bath of an apparatus for the wet chemical treatment of workpieces comprises at least one body (14). A space for receiving the shaft section is formed in the at least one body (14). The space comprises: a first section (17) having a cross-section centered on a reference axis (15), the circumference of which lies on a circle within at least a majority of the circumference; and a second section (18) extending in an axial direction from the first section (17) to an axial end of the space. The second section (18) has a respective cross-section at a plurality of, for example, all axial positions, a boundary of which has a radial distance from the reference axis (15) at at least one specific angular position ([phi] 0) equal to the length (R1) of the radius of the circle and has a radius of curvature extending from the reference axis (15) to the boundary. The respective cross-section of the second section (18) has a radial extent from the reference axis (15) within at least an angular position range ([-[phi] 1, [phi] 1) other than the specific angular position ([phi] 0), which increases relative to the radial extent of the cross-section of the first section (17) at a corresponding angular position.

Description

Technical Field

[0001] The invention relates to a device for rotatably supporting a section of an axle of a roller of a conveying system in a bath of an apparatus for wet-chemical treatment of workpieces, said device comprising at least one body,

[0002] wherein a space for receiving the shaft section is formed in the at least one body,

[0003] The space includes:

[0004] a first section having a cross-section centered on the reference axis and having a circumference lying on a circle over at least a majority of the circumference; and

[0005] a second section extending in the axial direction from the first section to an axial end of the space, and

[0006] The second segment has corresponding cross-sections at multiple (e.g., all) axial positions, a boundary of which has a radial distance from the reference axis at at least one specific angular position equal to the length of the radius of the circle and has a radius of curvature extending from the reference axis to the boundary.

[0007] The invention also relates to an assembly for installation in a conveying system, comprising:

[0008] at least one roller having an axis; and

[0009] At least one device according to any of the preceding claims for supporting a section of the shaft of the roller in a bath of an apparatus for wet-chemical treatment of workpieces.

[0010] The invention also relates to a system for conveying workpieces through a bath of an apparatus for wet-chemical treatment of workpieces, said system comprising at least one assembly comprising:

[0011] at least one roller having an axis; and

[0012] At least one means for supporting a section of the shaft of the roller in the bath.

[0013] The invention also relates to an apparatus for wet-chemical treatment of workpieces, for example for surface plating, comprising a container for forming a treatment bath and a system for conveying the workpieces through the bath. Background Art

[0014] CN 212668376 U discloses a roller conveying mechanism and a conveying device. The roller conveying mechanism includes a roller and a rotating shaft. Two support sleeves are respectively sleeved on both ends of the rotating shaft, and the two support sleeves rotate and support the two ends of the shaft respectively. When the support sleeve is worn, the support sleeve can be replaced, which can reduce the wear during the rotation of the shaft. The sleeve appears to pass through the bearing, and the bearing is obtained by providing two holes with a slightly displaced central axis extending through the entire bearing. The problem with this is that the processing liquid can pass through the bearing in a relatively large amount and reach the gear arranged on the other side of the bearing. This is usually undesirable. In the case where the wet chemical treatment includes electrodeless plating, a phenomenon called plate-out may occur, whereby the plating material is deposited on the gear in this case. In addition, replacing the sleeve requires the conveying mechanism to be stopped from service.

[0015] CN 215491814 U discloses a support and limiting structure, which includes: a first side wall; a second side wall, which is arranged opposite to the first side wall; and a circular support member, which is formed between the first side wall and the second side wall. The support and limiting structure may further include a bottom wall, which is fixedly connected to the first side wall and the second side wall and is arranged at the bottom of the channel for the circular shaft. The bottom wall blocks the circular shaft from moving downward out of the channel. The bottom wall has a groove connected to the channel to prevent liquid from accumulating on the upper surface of the bottom wall, and the groove can promote drainage. The problem with the groove is that the vertical position of the shaft is not very clearly defined, which can be a problem for the roller shaft carrying the workpiece. For processing purposes, the vertical position may need to be clearly defined. In addition, in this type of conveying system, a large number of roller assemblies are usually arranged in series. At least the lower support roller should not have a significant difference in vertical position to avoid damage to precision workpieces.

[0016] WO 03 / 069965A1 discloses a device for transporting flat workpieces in a conveyor line. In a preferred application, printed circuit boards and printed circuit foils are transported for processing in a wet chemical (horizontal or vertical) conveyor processing line. The device comprises at least one pair of rollers arranged on the respective sides of the transport plane and facing each other for transporting the workpiece and a transport drive associated with the rollers. The lower roller of the pair is carried in a fixed lower bearing, which determines the height of the workpiece positioning. The upper roller is freely loaded in a manner that it can automatically adjust according to the thickness of the workpiece. Thrust bearings are used for this purpose. The problem with the fixed lower bearing is that when the shaft is fixed, there is relatively little liquid in the bearing. In the case where the wet chemical treatment includes electrodeless plating, precipitation may occur on the roller shaft and the bearing. The deposited material must be removed from time to time, which means that the assembly including the roller shaft and the bearing must be removed and the processing equipment is temporarily out of service. In other types of processing, the bearing may become dry, thereby causing increased wear. Summary of the invention

[0017] It is an object of the present invention to provide a device, assembly, system and apparatus of the above mentioned type which requires relatively little maintenance to remain operational.

[0018] According to a first aspect, this object is achieved by a device according to the invention, characterized in that the corresponding cross-section of the second segment has a radial extent from the reference axis in at least one range of angular positions other than a specific angular position, which increases relative to the radial extent of the cross-section of the first segment at the corresponding angular position.

[0019] The device may be one of a pair, which is arranged at either axial end of a rotatable support shaft. The device may be embodied as a replaceable insert for a delivery system, or as a fixed component of such a delivery system. The device comprises at least one body, which defines a space for receiving a section of the shaft near the axial end of the shaft. The space may be defined in one body or in an assembly formed by a plurality of bodies joined together (e.g., by joining or welding). Most embodiments may be made in one piece, so that the device comprises a body, in which a space for receiving the shaft is formed. The first section of the space has a cross section at each of the axial position ranges (e.g., along the entire length in the axial direction), the circumference of the cross section being circular. The circumference has a closed shape. Non-functional deviations of the circumference from a circular shape are possible. This simply means that there may be scratches or shallow grooves in the inner wall surface of at least one body defining the first space, through which a significant flow of liquid in the axial direction is impossible. Otherwise, the circumference is located on a circle for a large portion of the circumference (e.g., at least 95% or at least 99% of the length of the circumference).

[0020] The length of the radius of the cross section of the first section (the distance from the axis to the inner surface of the body defining the first section of the space for receiving the shaft) will typically have a value only slightly larger than the shaft section received therein. Thus, when the device is mounted with a horizontally oriented reference axis, the shaft is reliably and accurately positioned with less play in the vertical and horizontal directions transverse to the reference axis.

[0021] In use, the majority of the shaft will extend in the axial direction from the second section to the periphery of the device. Only a relatively short section will extend in the axial direction from the first section to the periphery of the device. The relatively short section may be equipped with a gear to drive the shaft. The relatively long section will support the workpiece as it is conveyed through the bath. The relatively narrow gap in the first section between the inner surface defining the space and the outer surface of the shaft section arranged in the first section provides a relatively high flow resistance, so that a large amount of liquid flow in the axial direction is prevented from passing completely through the device.

[0022] On the other hand, the second section is expanded in the radial direction so that more liquid can surround the shaft section contained in the second section of the space for receiving the shaft. This helps to reduce precipitation. In addition, more liquid can achieve the transition from the second section to the first section, so that the first section will not be easy to dry out, for example, when the shaft is idle. This helps to prevent wear. The second section has a corresponding cross section at each axial position, and its boundary is at a radial distance from the reference axis at at least one specific angular position equal to the length of the radius of the circle (the circumference of the cross section of the first section is located on the circle). At the specific angular position, the boundary also forms a circular segment with a radius of curvature extending from the reference axis to the boundary. Therefore, this radius of curvature is the same as the radius of curvature of the circle. When the device is in the operating position, the specific angular position marks the bottom of the second space, wherein the reference axis extends horizontally. The shaft with the corresponding radius is rotatably supported in the operating position. Therefore, the shaft is supported in one direction along the length of both the first and second sections. In use, this is the direction in which the weight of the workpiece is carried when the device is in the operating position, wherein the reference axis is horizontally oriented. The supported length of the shaft section is relatively long relative to the dimension of at least one main body in the axial direction, so that the shaft does not sag significantly under load.

[0023] The observation that the radial extent of the cross section of the space in the second section increases relative to the radial extent of the cross section in the first section in at least one range of angular positions other than a certain angular position means that there is a change in cross section at the transition between the first section and the second section. In this way, the device is distinguished from a device comprising a single hole having a slight non-roundness due to manufacturing tolerances.

[0024] The cross section of the second segment may have a constant shape at every axial position of the second segment, or may vary.The boundaries of the cross section need not be a closed shape at every axial position in the second segment.

[0025] The term angular position has the ordinary meaning associated with the term when defining a position in a cylindrical coordinate system. In this case, the cylindrical coordinate system has a reference axis as the principal axis.

[0026] In an embodiment of the device, when the device is oriented with a horizontally oriented reference axis to support the shaft segment at the specific angular position, the specific angular position comprises the angular position of the lowest point of the boundary of the cross-section of the second segment.

[0027] Typically, the section of the shaft received in the space will have a cylindrical shape having a radius slightly smaller than the radius of the cross section of the first section of the space. The shaft is supported at (and within a range around) a specific angular position by a correspondingly shaped boundary section. This embodiment is particularly useful in situations where the roller carries the weight of the workpiece.

[0028] In an embodiment, the first section is cylindrical, with its cylinder axis coinciding with the reference axis.

[0029] This means that the cross section of the first section is uniform over the range of axial positions that the first section extends. The shaft remains relatively well in position.

[0030] In an embodiment of the device, the at least one body defines at least one split through the at least one body to fluidly interconnect an exterior of the at least one body and the second section, the split extending at an angle greater than zero relative to the reference axis.

[0031] Thus, the split extends transversely to the reference axis. The angle may be 90° so that the split extends in a radial direction. The direction in which the split extends corresponds to the flow direction of the liquid. This embodiment helps to ensure that in the presence of a shaft section, enough liquid can reach the second section of the space, in particular in the case where the shaft section has an axial positioning feature of the axial abutment means. This feature can facilitate axial closure of the second section of the space. The split still allows liquid to enter the second section of the space. At least one of the at least one split may be in the form of a channel.

[0032] In an example of any embodiment, wherein at least one body defines at least one breach through the at least one body to fluidly interconnect an exterior of the at least one body with a second section, the breach extending at an angle greater than zero relative to a reference axis, the breach being at least two in number.

[0033] This allows liquid to flow through the second section of the space in the presence of the shaft section. Liquid can enter through one split and exit through the other split. The orientation of the split (e.g., relative to vertical) can, for example, promote a particular flow direction. Alternatively or in addition, the shaft can be equipped with flow enhancement features, such as features that allow the shaft to act as an impeller or at least entrain liquid as the shaft rotates.

[0034] In an example of any embodiment, wherein at least one body defines at least one slit passing through the at least one body to fluidly interconnect the exterior of the at least one body with the second section, the slit extending at an angle greater than zero relative to a reference axis, at least one sub-segment of the second section of the space positioned at an axial end of the space is defined in a section of the at least one body protruding in at least an axial direction relative to an adjacent portion of the at least one body and is equipped with at least one of the at least one slit.

[0035] In the case where it is arranged in a section of at least one body that protrudes in at least the axial direction relative to an adjacent portion of the at least one body, the split can be relatively short. Since a subsection of the second section of the space is located at the axial end of the space, liquid passing through the split also passes through the second section of the space to and from the axial end of the space. There are fewer or no stagnant areas.

[0036] In a particular variation of this embodiment, the protruding section further protrudes in an opposite lateral direction relative to an adjacent portion of at least one main body to form a flange.

[0037] The flange may engage a locating feature on the shaft section to limit axial movement of the shaft. The flange may also or alternatively cooperate with a matching feature of the mounting structure to mount the device without fasteners. The flange need not protrude more than 360° laterally, i.e. need not be annular in shape. In this case, laterally also encompasses protruding downwards.

[0038] In an embodiment of the device, at least one of the bodies is provided with a flange on a side in the axial direction opposite to a side at which an axial end of the space into which the second section extends is located.

[0039] The flange is formed by a protruding ridge, rib or edge. The protrusion direction is transverse to the reference axis. The flange need not protrude more than 360°, i.e. need not have an annular shape. If this is not the case, the flange may comprise discrete segments. The flange may engage locating features on the shaft segments to limit axial movement of the shaft. The flange may also or alternatively cooperate with a matching feature of a mounting structure to mount the device without the need for fasteners.

[0040] In an embodiment, the device is configured to support a section of the shaft of the second roller for rotation about a further reference axis parallel to the reference axis, the further space for receiving the section of the shaft of the second roller being defined by the at least one body.

[0041] This embodiment is suitable for use in a conveyor system for conveying flat workpieces (e.g., a horizontal conveyor system). The workpiece can then be conveyed between rollers. At least one of the rollers will be a drive roller. Conveying the workpiece between rollers helps to avoid slippage. In the case of very thin workpieces, they can be kept flat to avoid wrinkling and thus provide a relatively uniform surface treatment.

[0042] In a specific example of this embodiment, when the device is oriented with a horizontally oriented reference axis to support the shaft segment at a specific angular position, the space for receiving the shaft segment is at a lower level, for example, below the further space.

[0043] Therefore, the space including the first and second sections is the space for accommodating the section of the lower shaft of the two shafts. This is the shaft of the load-bearing rollers in the horizontal conveying system. The shaft is supported in the axial direction over a relatively large range. In contrast, the further space can be shorter in the axial direction than the combination of the first and second sections. Even if this is not the case, in use, the further space does not need to be completely immersed in the liquid of the treatment bath, and it is less important that the second shaft is supported at a specific height. Therefore, the further space does not need to include a section arranged to receive the section of the lower shaft whose shape is similar to the first section of the space.

[0044] In an example of any embodiment, wherein the device is configured to support a segment of the shaft of the second roller for rotation about a further reference axis parallel to the reference axis, a further space for receiving the segment of the shaft of the second roller is defined by at least one body, the further space and the second segment being fluidly interconnected by at least one channel formed in the at least one body.

[0045] This allows the establishment of liquid flow through the second section of the space for receiving the shaft section. In use, with the second section at a level below the further space, liquid flow will be established by gravity. Since the second roller will generally not be load-bearing, the shaft of the second roller will not be so firmly pressed against the surface of the window in which the channel is formed. Therefore, the channel can be a substantially straight channel. Alternatively, the channel can be connected to the further space through a transverse pore in the inner surface defining the further space. However, straight channels are easier to form, specifically in a molded body. In an embodiment, at least one body defines at least one rift that passes through at least one body to fluidly interconnect the exterior of at least one body with the second section, the rift extending at an angle greater than zero relative to the reference axis, and the channel may correspond to one of the at least one rift.

[0046] In an example of any embodiment, wherein the device is configured to support a segment of the shaft of the second roller for rotation about a further reference axis parallel to the reference axis, a further space for receiving the shaft segment of the second roller is defined by at least one body, the further space being elongated in a direction transverse to the reference axis and extending away from the space for receiving the shaft segment.

[0047] The elongated shape allows some movement of the section of the shaft of the second roller to accommodate workpieces of varying thicknesses.

[0048] In an example of any embodiment, wherein the device is configured to support a segment of the shaft of the second roller for rotation about a further reference axis parallel to the reference axis, a further space for receiving the shaft segment of the second roller is defined by at least one body, the further space has a boundary defined by an inner surface of at least one body, the boundary is U-shaped as seen in the axial direction, and the shaft segment of the second roller can be inserted into the further space between the outer edges of the U-shape.

[0049] This means that when the device is oriented with a horizontally oriented reference axis to support the shaft section at a specific angular position, the further space is open at the top. The shaft of the second roller can simply fall into the further space. This simplifies installation. In addition, the second roller can be used as required. If the workpiece is too thick or does not need to be held between the rollers, the second roller can be lifted out of the conveying system without using any tools.

[0050] According to a further aspect, an assembly according to the invention for installation in a conveying system comprises at least one roller having an axis and at least one device according to the invention for supporting a section of the axis of the roller in a bath of an apparatus for wet-chemical treatment of workpieces.

[0051] In general, the assembly will include a pair of devices, each supporting two respective segments of each roller shaft according to the invention. The devices may be identical, mirror images of each other, or of different shapes, differing only in having similar spaces for receiving segments of one of the shafts. The assembly may be replaceable, for example in a tool-less manner, or the assembly may be permanently installed in the conveying system. Thus, the device for supporting the roller shaft segments may be integrated into a larger structure, or embodied as a replaceable insert.

[0052] In an embodiment of the assembly, the shaft is provided with a positioning sleeve which axially adjoins the means for rotatably supporting a section of the shaft.

[0053] In this embodiment, the first section of the space for receiving the roller segments limits the movement of the roller in the manner of a cylindrical joint.A face of the device (eg a face of at least one body) limits the axial movement of the roller.

[0054] In an embodiment of the assembly, the shaft carries at least one gear at an axial end section which projects in axial direction from a side of the device for rotatably supporting a section of the shaft, said section being axially closer to the first section of the space than to the second section of the space.

[0055] The first section of space for receiving the roller shaft section limits the amount of liquid that can reach the gear, thereby helping to reduce precipitation onto the gear. The gear may be adapted to cooperate with a gear on the drive shaft to at least cause the roller to rotate. The gear may mesh with a gear on a further roller shaft also rotatably supported by the same device. The shaft may carry two gears, one of which performs the first of the two functions and the other performs the second function.

[0056] According to another aspect, a system according to the invention for conveying workpieces through a bath of an apparatus for wet chemical treatment of workpieces comprises at least one assembly, for example an assembly according to the invention comprising: at least one roller having an axis; and at least one device according to the invention for supporting a section of the axis of the roller in the bath.

[0057] An embodiment of the system includes at least one mounting structure for receiving an insert including means for supporting a section of a shaft of a roller in the bath.

[0058] The insert may correspond to a device, ie comprise no further components.

[0059] In instances of any embodiment comprising at least one mounting structure for receiving an insert, the insert comprising means for supporting a segment of a roller shaft in a bath, the mounting structure and the insert having interlocking shapes to secure the insert in position in the mounting structure at least in an axial direction.

[0060] Therefore, the replacement of the insert or the assembly comprising the insert and the roller can be done quickly without the use of tools. There are no fasteners that need to be loosened and tightened and that could fall into the bath.

[0061] According to another aspect, an apparatus according to the invention for wet-chemical treatment of workpieces, for example for surface coating, comprises a container for forming a treatment bath and a system according to the invention for conveying workpieces through the bath. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The present invention will be explained in further detail with reference to the accompanying drawings, in which:

[0063] Figure 1 is a perspective view of an assembly of two rollers and two bearing inserts for installation in a conveying system;

[0064] Figure 2 yes Figure 1 a perspective view of a first end of the assembly;

[0065] Figure 3 yes Figure 1 and 2 a perspective view of a second opposite end of the assembly;

[0066] Figure 4 is a perspective view of the second end from a different angle;

[0067] Figure 5 is a perspective view of one of the bearing inserts;

[0068] Figure 6 yes Figure 5 A side view of a perspective projection of a bearing insert;

[0069] Figure 7 yes Figure 5 and 6 A top view of a perspective projection of a bearing insert;

[0070] Figure 8 yes Figures 5 to 7 A rear view of a perspective projection of a bearing insert;

[0071] Fig. 9 yes Figures 5 to 8 A front view of a perspective projection of a bearing insert;

[0072] Fig.10 yes Figures 5 to 9A front view of a parallel projection of a bearing insert;

[0073] Fig.11 yes Figures 5 to 10 A detailed view of a parallel projection of a portion of the front side of the bearing insert;

[0074] Fig.12 yes Figures 5 to 11 a cross-sectional view of a bearing insert; and

[0075] Fig.13 yes Figures 5 to 12 Perspective view of the bearing insert.

[0076] An assembly 1 (not shown) for installation in a conveying system for conveying workpieces through a bath (not shown) of an apparatus for wet chemical treatment of workpieces (not shown) Figure 1 ) is shown as a replaceable unit herein. In the conveying system, in use, the entire series of these assemblies 1 will be installed in the direction in which the workpiece is conveyed. The assembly 1 will be installed so as to be at least partially immersed in the liquid of the bath. The workpiece can be a flat workpiece, for example, a plate (for example, a printed circuit board), a panel (for example, a glass panel for a display device), a wafer or a foil. The workpiece can be relatively thin, for example, with a thickness from about 25m. The width of the workpiece (relative to the transport direction) can be about 50mm to 1000mm, for example, between 100mm and 800mm. The treatment can be different due to different baths in the equipment. One of the treatments can be, for example, an electrodeless surface plating using copper. Other treatments include a decontamination process.

[0077] The assembly 1 comprises a first roller 2 and a second roller 3. In use, a workpiece is transported between the pair formed by the first roller 2 and the second roller 3. The first roller 2 comprises a first shaft 4 to which a wheel is mounted for rotation with the first shaft 4. The second roller 3 likewise comprises a second shaft 5 to which a wheel is mounted for rotation with the second shaft 5.

[0078] In an alternative embodiment, the rollers 2, 3 may each comprise a single full-body roller rather than wheels mounted on axles. These full-body rollers may still have a height such that the contact area with the workpiece is limited. The wheels on the first axle 4 may be axially offset relative to the wheels on the second axle 5 so that the upper side of the workpiece contacts the lower side of the workpiece at different axial positions.

[0079] In the replaceable case, the assembly 1 comprises first and second bearing inserts 6a, 6b at opposite ends of the first and second shafts 4, 5. The bearing inserts 6a, 6b are configured to drop into a mounting structure (not shown) formed at the upper end of a wall of the conveying system.

[0080] In this case, each of the bearing inserts 6a, 6b comprises means for supporting a respective section of both the first shaft 4 and the second shaft 5. The supported section is close to the axial end of the respective shaft 4, 5, but does not extend all the way to said axial end.

[0081] In this embodiment, the first bearing insert 6a and the second bearing insert 6b are identical and are symmetrical with respect to a symmetry plane in which the rotation axes of the first shaft 4 and the second shaft 5 lie.

[0082] The first shaft 4 is provided with a bevel gear 7 at one end and a large gear 8 at an axial position between the bevel gear 7 and the second bearing insert 6b. The first shaft 4 is provided with a first positioning sleeve 9 ( Figure 2 In addition, there is a second positioning sleeve 10 ( Figure 3 and 4 ), which adjoins the second bearing insert 6b on a side of the second bearing insert 6b opposite to the side on which the bevel gear 7 and the large gear 8 are arranged.

[0083] Similarly, the second shaft 5 is provided with a large gear 11. This large gear 11 meshes with the large gear 8 on the first shaft 4, so that there is no need to provide a bevel gear for the second shaft 5. The rotation of the first shaft 4 and the second shaft 5 is synchronized by the meshing large gears 8 and 11. The second shaft 5 is also provided with a first positioning sleeve 12 ( Figure 2 In addition, there is a second positioning sleeve 13 ( Figure 3 and 4 ), which adjoins the second bearing insert 6b on a side of the second bearing insert 6b opposite to the side on which the large gear 11 is arranged.

[0084] Since the first bearing insert 6a and the second bearing insert 6b are identical, the remaining description will not distinguish between the two.

[0085] In the illustrated embodiment, the bearing insert 6 ( Figures 5 to 13 ) is formed by a single body 14, for example by molding. The body 14 can be made of a non-conductive material. For example, the body 14 can be made of a plastic or ceramic material.

[0086] It is convenient to define a first reference axis 15 and a second reference axis 16 that are substantially coincident with the rotation axes of the first shaft 4 and the second shaft 5 ( Fig.12 ). When the assembly 1 is installed in a conveying system, the first reference axis 15 and the second reference axis 16 will be oriented substantially horizontally. The angular position φ ( Fig.11In use, an angular position φ of 0° corresponds to the 12 o'clock position on a clock face, as seen in the axial direction from the side of the bearing insert 6 where the majority of the first shaft 4 is located.

[0087] In subject 14( Fig.12 ) forms a space for receiving a section of the first shaft 4. This space extends between opposite sides of the body 14 in the axial direction. The space is defined by the inner surface of the body 14. The first section 17 is substantially cylindrical and centered on the first reference axis 15. The first section 17 is delimited by a first inner surface section. The first section 17 has a radius of a first length R1.

[0088] In the illustrated embodiment, the first section 17 extends in the axial direction into the body 14 from an axial end of a space forming a void in the outer surface of the body 14. The first section 17 extends in the axial direction until a transition to the second section 18. In another embodiment, there may be a further section on the side of the first section 17 opposite to the side where the second section 18 is located.

[0089] The second section 18 extends in the axial direction from the transition to the first section 17 to the axial end of the space. The second section 18 is also defined by the inner surface of the body 14, but the relevant section of the inner surface is not closed around the first reference axis 15 at each axial position. In fact, there is a break into the second section 18, as will be explained. In addition, the cross-sectional shape deviates from a circle at each axial position, regardless of whether there is a break at said axial position.

[0090] At each axial position, the inner surface confines the second section 18 within an angular position range [φ1,360°-φ1] centered at a specific angular position φ0 corresponding to the six o'clock position on the clock face, i.e., 180° in the described coordinate system. The size of this range [φ1,360°-φ1] is less than 180°, for example, less than 90°. Within the range [φ1,360°-φ1], the second section 18 is simply a continuation of the first section 17. At other angular positions, the radial extent of the second section 18 is greater than the radial extent of the first section 17 at the corresponding angular position. In other words, at least the upper half of the second section 18 is enlarged in the radial direction relative to the first section 17. Therefore, when the cylindrical section of the first shaft 4 is received in the space, there is a larger volume for the liquid to surround the first shaft 4.

[0091] In the illustrated embodiment, the radius of the second section 18 (where this radius is defined by the inner surface of the body 14 ) has a maximum length R2 at an angular position 180° removed from a particular angular position φ0 where the radius has the same length R1 as in the first section 17 .

[0092] The second section 18 extends axially into a subsection 19 formed in the first flange 20. In use, the second positioning sleeve 10 can axially abut the first flange 20. This will generally close the second section 18 to the liquid in the axial direction, so that the first flange 20 ( Figures 9 to 11 ) is defined in the first section 17. The split 21 extends in the radial direction, i.e. at an angle of 90° to the first reference axis 15. In the illustrated embodiment, the split 21 is located at an angular position 180° removed from a specific angular position φ0, where the radius has the same length r1 as in the first section 17. Thus, the first flange 20 is horseshoe-shaped, seen in the axial direction.

[0093] This position of the split 21 is appropriate at least in view of another function of the first flange 20, which is to locate the bearing insert 6 in a mounting structure provided for the bearing insert 6 in the conveying system. The first flange 20 provides a form lock, allowing the bearing insert 6 to be securely mounted simply by placing the bearing insert 6 into the mounting structure. The same function is achieved by the second flange 22 on the same side of the bearing insert 6 and the third flange 23 on the opposite side of the bearing insert 6, as seen in the axial direction.

[0094] All flanges 20 , 22 , 23 of the illustrated embodiment are an integral part of the body 14 , ie are made in one piece with the rest of the body 14 .

[0095] The sections of the second shaft 5 are supported for rotation in a different manner than the sections of the first shaft 4. Seen in the axial direction, the upper section of the body 14 defines an inner surface 24 having a substantially U-shaped cross section. This inner surface 24 partially defines a further space 25 for receiving the section of the second shaft 5. In the illustrated embodiment, the cross section is constant along the axial extent of the further space 25, differing only in the position or positions at which the apertures are defined in the inner surface 24.

[0096] In the illustrated embodiment, there is a position at which a gap is defined at the end of a channel 26 which separates the further space 25 from the opening for receiving the first shaft 4 ( Figure 7 and 12 ). Thus, this channel 26 forms a second split through the body 14 to fluidly interconnect the exterior of the body 14 (via the further space 25) with the second section 18 of the space for receiving a section of the first shaft 4. The effect is that there is a flow of liquid through the second section 18 and through the channel 26 and the split 21 defined in the first flange 20.

[0097] The bottom of the U-shape, seen in the axial direction, has the shape of a circle segment, wherein the radius extends from the second reference axis 16 to the inner surface 24. The circle segment extends over 180° or less, but typically more than 90°. For example, the radius may have the same length r1 as the radius of the first section 17 of the space for receiving the section of the first shaft 4.

[0098] It will be appreciated that the further space 25 is elongated in a direction transversely and through the first reference axis 15 and the second reference axis 16 (i.e., a direction extending away from the space for receiving the section of the first shaft 4). Therefore, the second shaft 5 is able to move between the outer edges of the U-shaped inner surface in said direction. The gearwheels 8, 11 are equipped with teeth of appropriate shape and size to enable them to mesh within a range of movement. When used in a conveying system, the further space 25 is positioned above the space for receiving the section of the first shaft 4. Therefore, the first roller 2 bears the load of the workpiece. The second roller 3 holds the workpiece against the first roller 2 to move the workpiece with limited or no slip. The freedom of movement granted by the elongated shape of the further space 25 allows a range of workpiece thicknesses to be accommodated. In addition, the second shaft 5 is at least slightly lifted from the inner surface 24 at intervals. This releases the pores into the channel 26, which can actually provide a limited pumping effect that supports the flow of liquid through the first shaft 4.

[0099] Regardless, the orientation of the channel 26 is such that the channel 26 extends substantially vertically in use, since the further space 25 is located above the second section 18 when the reference axes 15 , 16 are oriented horizontally.

[0100] The second flange 22 of the second bearing insert 6b cooperates with the gear wheel 11. The third flange 23 of the second bearing insert 6b cooperates with the second positioning sleeve 13. The third flange 23 of the first bearing insert 6a cooperates with the first positioning sleeve 12. Therefore, the axial movement of the second shaft 5 is restricted.

[0101] The first roller 2 is able to support the workpiece and remain in position relatively well. The weight of the first roller 2 is carried in the bearing inserts 6a, 6b in a relatively long section at either end. Lateral movement is prevented by the inner surface of the first section 17 defining a space for receiving the shaft section. Sedimentation and drying of the bearing surface are prevented by enlarging the second section 18.

[0102] The invention is not limited to the embodiments described above, which may vary within the scope of the appended claims. For example, the second flange 22 need not be U-shaped as described. Pulleys may be used to synchronize the rotation of the first roller 2 and the second roller 3, for example allowing the assembly 1 to accommodate a wider range of workpiece thicknesses. Instead of providing a pair of rollers 2, 3 and a pair of bearing inserts 6a, 6b for each assembly 1, a pair of bearing inserts may support multiple pairs of rollers, for example by including a set of spaces of the configuration described above and further spaces 25, which are located adjacent to each other. In other words, two bearing inserts 6 may be integrated to support two pairs of segments of the first shaft 4 and the second shaft 5. Although the assembly 1 described above has two bearing inserts 6a, 6b having the features described in detail herein, it is possible to provide only one such bearing insert at one axial end of the first roller 2 and provide a bearing insert at the other axial end having a differently configured space for receiving a segment of the first shaft 4 (for example, a cylindrical space or a space with a cross-sectional shape similar to the second segment 18). This may be sufficient, for example, if it is desired to reduce precipitation only at the axial end where the gearwheel 8 and the bevel gear 7 are located.

[0103] Component Symbol List

[0104] 1 Assembly

[0105] 2 First Roller

[0106] 3 Second roller

[0107] 4 First axis

[0108] 5 Second axis

[0109] 6a,b bearing insert

[0110] 7 Bevel gear

[0111] 8 Large gear on the first shaft

[0112] 9 First positioning sleeve on first axis

[0113] 10 Second positioning sleeve on the first axis

[0114] 11 Large gear on the second shaft

[0115] 12First positioning sleeve on the second axis

[0116] 13 The second positioning sleeve on the second shaft

[0117] 14 Main Body

[0118] 15First reference axis

[0119] 16 Second reference axis

[0120] 17 The first section of space

[0121] 18 The Second Segment of Space

[0122] 19 sub-segments

[0123] 20First flange

[0124] 21 Rift

[0125] 22 Second flange

[0126] 23 Third flange

[0127] 24Inner surface

[0128] 25 Further Space

[0129] 26 channels.

Claims

1. A device for rotatably supporting a section of an axle (4) of a roller (2) of a conveying system in a bath of an apparatus for wet-chemical treatment of workpieces, the device comprising at least one body (14), wherein a space for receiving the shaft section is formed in the at least one body (14), The space includes: a first section (17) having a cross-section centered on the reference axis (15) and having a circumference lying on a circle over at least a majority of said circumference; and a second section (18) extending in the axial direction from the first section (17) to an axial end of the space, and wherein the second section (18) has corresponding cross sections at a plurality of, for example, all, axial positions, a boundary of which, at at least one specific angular position (φ0), is at a radial distance from the reference axis (15) equal to the length (R1) of the radius of the circle and has a radius of curvature extending from the reference axis (15) to the boundary, characterized in that The corresponding cross section of the second segment (18) has a radial extent from the reference axis (15) within at least one angular position range ([-φ1, φ1]) other than the specific angular position (φ0), which increases relative to the radial extent of the cross section of the first segment (17) at the corresponding angular position.

2. The device according to claim 1, Wherein when the device is oriented with the reference axis (15) oriented horizontally to support the shaft segment at the specific angular position (φ0), the specific angular position includes the angular position of the lowest point of the boundary of the cross-section of the second segment (18).

3. The device according to claim 1 or 2, The first section (17) is cylindrical, wherein the cylinder axis coincides with the reference axis (15).

4. The device according to any one of the preceding claims, wherein the at least one body (14) defines at least one split (21, 26) through the at least one body (14) to fluidly interconnect an exterior of the at least one body (14) with the second section (18), the split (21, 26) extending at an angle greater than zero relative to the reference axis (15).

5. The device according to claim 4, At least one subsection (19) of the second section (18) of the space positioned at the axial end of the space is defined in a section (20) of the at least one body (14) protruding in at least the axial direction relative to an adjacent portion of the at least one body (14) and is provided with at least one of the at least one slit (21).

6. The device according to any one of the preceding claims, The device is configured to support a section of the shaft (5) of the second roller (3) for rotation about a further reference axis (16) parallel to the reference axis (15), and a further space (25) for receiving the shaft section of the second roller (3) is defined by the at least one body (14).

7. The device according to claim 6, Wherein when the device is oriented with the reference axis (15) oriented horizontally to support the shaft segment at the specific angular position (φ0), the space for receiving the shaft segment is at a lower level, for example below the further space (25).

8. The device according to claim 6 or 7, wherein the further space (25) and the second section (18) are fluidly interconnected by at least one channel (26) formed in the at least one body (14).

9. The device according to any one of claims 6 to 8, The further space (25) is elongated in a direction transverse to the reference axis (15) and extends away from the space for receiving the shaft section.

10. The device according to any one of claims 6 to 9, wherein the further space (25) has a boundary defined by an inner surface (24) of the at least one body (14), the boundary being U-shaped as seen in the axial direction, and The shaft section of the second roller (3) can be inserted into the further space (25) between the outer edges of the U-shape.

11. An assembly for installation in a conveying system, comprising: at least one roller (2) having a shaft (4); and At least one device (6) according to any of the preceding claims for supporting a section of the shaft (4) of the roller (2) in a bath of an apparatus for wet-chemical treatment of workpieces.

12. The assembly according to claim 11, The shaft (4) is provided with a positioning sleeve (9, 10) which axially adjoins the device (6) for rotatably supporting a section of the shaft (4).

13. An assembly according to claim 11 or 12, The shaft (4) carries at least one gear (7, 8) at an axial end section which projects in the axial direction from one side of the device (6b) for rotatably supporting a section of the shaft (4), the section being axially closer to a first section (17) of the space than to a second section (18) of the space.

14. A system for conveying workpieces through a bath of an apparatus for wet-chemical treatment of workpieces, the system comprising at least one assembly, for example according to any one of claims 11 to 13, comprising: at least one roller (2) having a shaft (4); and At least one device (6) according to any one of claims 1 to 13, for supporting a section of the shaft (4) of the roller (2) in the bath.

15. An apparatus for wet chemical treatment of workpieces, for example for surface coating, comprising a container for forming a treatment bath and a system according to claim 14 for conveying the workpieces through the bath.

Images