FI3981653T3

FI3981653T3 - Rim cleaning unit and corresponding operating method

Info

Publication number: FI3981653T3
Application number: FIEP20201153.2T
Authority: FI
Inventors: Andreas Nolandt; Stephan Aumann; Bernhard Bork
Original assignee: Hofmann Maschinen Und Anlagenbau Gmbh
Priority date: 2020-10-09
Filing date: 2020-10-09
Publication date: 2023-06-30
Also published as: HUE063572T2; EP3981653A1; EP3981653B1; PT3981653T; ES2949083T3

Description

RIM CLEANING UNIT AND CORRESPONDING OPERATING METHOD

Description

The invention relates to a rim cleaning station and a corresponding operating method.

So-called complete wheels of motor vehicles respectively comprise a rim and a tyre. In order to compensate for imbalances, which could negatively affect the even running of the wheel, one or more balancing weights are usually fitted in the circumference of the inner rim surface, — generally by adhesive bonding, after a measurement in this regard.

In order to ensure durable attachment of the balancing weight, the attachment or bonding surface must be cleaned before it is fitted. Even small quantities of contamination — perhaps in the form of oil, grease, emulsions, soaping agents, etc. — can adversely affect the adhesiveness of the adhesive. Cleaning must therefore be done carefully and reliably.

The radial position of the fitting point on the rim is generally determined beforehand.

Typically, there are two possibilities, namely one inside and one outside. However, the circumferential position is possibly not yet known at the time of cleaning, and so it may be — necessary to clean the entire circumference for two cleaning tracks.

DE 10 2015 117 458 B4 discloses a method (and a device) for cleaning an attachment surface for a balancing element on a motor vehicle wheel, wherein a cleaning device in the shape of a brush is attached to an arm of an industrial robot. The brush is regularly dipped into a container — of cleaning fluid and wetted, and then guided to the rim to be cleaned. This is relatively laborious and requires a high consumption of cleaning fluid. Furthermore, a release (emission) of environmentally harmful cleaning fluid can occur in the workplace of the operating personnel. US-B-7325268 discloses the generic term of claim 1.

The invention is based on the aim of providing a rim cleaning station enabling reliable and efficient rim cleaning in a complete wheel for subsequently fitting a balancing weight. The rim cleaning station must allow a high cycle rate and low consumption of resources, and must be maintenance friendly. A corresponding method for cleaning a rim must furthermore be provided.

With reference to the device, the aim is achieved according to the invention by a rim cleaning station with the characteristics of claim 1. The corresponding method is defined in claim 10.

A rim cleaning station is therefore provided with + a conveyor for infeeding and outfeeding a complete wheel including a tyre andarim, e a centering and rotating device for centering and rotating the complete wheel, and e a cleaning device with a cleaning head which can be brought into contact with the rim during a cleaning process, wherein the cleaning device has a winding roller and an unwinding roller for a cleaning belt, a roller and/or belt drive and guide means for guiding the cleaning belt around the cleaning head.

The invention is based on the consideration that good results can be achieved in rim cleaning by dry cleaning with a cleaning cloth. The emissions load in the workplace is low, and used cleaning cloths can be at least partially recycled. However, the cleaning process, hence rubbing — the cleaning cloth on the rim, must be extensively automated for an efficient workflow, and the region of the cleaning cloth in contact with the rim must be changed regularly. This means that a region of the cloth saturated with gathered dirt must be replaced with a still fresh, unused region of the cloth. This is best done by providing the cleaning cloth as an elongated belt on an unwinding roller, moved forward continuously or in cycles and guided past a cleaning head, — which brings the cleaning belt into contact with the point on the rim to be cleaned, and finally the used belt section is wound back onto a winding roller — similar to conveying a film on an analogue film projector. The cleaning belt can be moved forward by means of a drive for one or both of the rollers and/or by means of a drive engaging directly with the belt. The guide means are preferably running rollers or pulleys and/or sliding components.

In an advantageous configuration, the winding roller, the unwinding roller and the roller and/or belt drive are arranged in a cleaning unit, from which a cantilever projects which carries the cleaning head. In this case, the cleaning head can be a very compact design so that it can engage with the rim region to be cleaned, even with limited accessibility.

The cleaning device is advantageously mounted on a holding and adjusting device arranged below the conveyor, wherein the holding and adjusting device preferably enables displacing the cleaning device - and thereby the cleaning head — in three spatial directions as well as preferably pivoting about at least one axis.

In an expedient configuration, the conveyor comprises a roller conveyor, which preferably comprises a roller field with a recess for feeding through the cleaning head. This assists the compact installation of the holding and adjusting device and the cleaning unit below the conveyor.

The centering and rotating device advantageously comprises at least one driven roll which can be pressed against the tread on the tyre of the complete wheel by an adjusting drive in order to rotate the complete wheel. A combination of two driven and two rolls rotating with them is particularly preferable, rolls which are seated at the corners of a sguare enclosing the tyre and — which clamp the complete wheel as required by means of suitable adjustment of the distances, and furthermore rotate the complete wheel as reguired by transmitting the movement from the driven rolls.

The roller conveyor advantageously comprises two roller fields operable in opposite directions — (one on the side of the recess for the cleaning head and one on the other side), which additionally support the rotation of the complete wheel according to the desired direction of rotation. This means that, for moving the wheel forward, both roller fields are operated in the same way to support the rotation of the wheel in opposite directions.

The cleaning head preferably comprises a cleaning roller for guiding and for pressing the cleaning belt against the rim. The cleaning roller is seated at the end of the aforementioned cantilever. The cantilever is pressed against the rim during cleaning by a pneumatic cylinder.

The cantilever is float-mounted and balances movements in both directions and permanently applies a preload to the cleaning roller. Appropriate pressure is thereby achieved even with low tolerances in the movement of the holding and adjusting device.

The cleaning belt preferably consists of a textile fabric, microfibers in particular, if necessary, with but preferably without a portion of stretch fibres. The cleaning belt is preferably 25 mm in width.

From a procedural viewpoint, the invention includes a method for cleaning a rim in a complete wheel including the rim and a tyre, wherein in a rim cleaning station of the type described e the complete wheel is conveyed into a working position by means of the conveyer and is centred by means of the centering and rotating device, + the cleaning head is pressed against the rim by means of the holding and adjusting device, and then e the complete wheel is rotated about its wheel axis by means of the centering and rotating device while the cleaning head is stationary so that a cleaning track on the rim is cleaned in the full 360° circumference or in a partial section thereof.

In this case, two cleaning tracks on the rim are advantageously successively cleaned, wherein for changing the track, the position of the cleaning head is changed by means of the holding and adjusting device and wherein before, after and/or during the cleaning, the cleaning belt is moved forward by the roller and/or belt drive.

The cleaning is advantageously performed with a dry cleaning belt without liguid wetting.

To reach a service position, the cleaning device is advantageously positioned and tilted by the holding and adjusting device in such a manner that at least the cleaning head and preferably also the cleaning unit is freely accessible. For this purpose, the cleaning head is preferably tilted downwards and the cleaning device is retracted sideways from the frame. The former preferably takes place automatically, the latter can be done manually if necessary.

The working seguences during cleaning are expediently fully automatically controlled by an 5 electronic system controller. The transfer of the cleaning device to the service position can be done at least partially manually as mentioned above.

It is particularly advantageous for the complete wheel to be conveyed through the rim cleaning station lying down and to be cleaned there. This means that the work required to place the wheel in the working position is minimal.

An embodiment example of the invention, from which further characteristics, aims and advantages emerge, is described below with reference to the attached drawings. These show:

FIG. 1 a perspective view of a rim cleaning station according to the invention,

FIG. 2-5 respectively a longitudinal section through the rim cleaning station, namely during different operating conditions,

FIG. 6 a further perspective view of the rim cleaning station, here in a service position,

FIG. 7 a top view relevant to FIG. 9 of the rim cleaning station from above,

FIG. 8 a detail from FIG. 3 with a cleaning head in a preliminary position, and

FIG. 9 a corresponding detail with a cleaning head in a working position.

The rim cleaning station 2 illustrated in the figures is used to clean a rim 4 wherein a compete wheel 8 comprising a rim 4 and a tyre 6 (motor vehicle wheel, wheel in short), namely in a region on the inside of the rim 4, which is intended for subsequently fitting a so-called balancing weight, in particular by adhesive bonding. Since the later fitting or bonding position is not yet known during the cleaning process, possibly with respect to its circumferential position, it may be necessary to clean a complete circumferential cleaning track (in the full 360° circumference) on the inside of the rim 4. This normally concerns two separate cleaning tracks 10, 12 (see FIG. 2) distanced from each other in the axial direction of the rim 4, which include the totality of possible fitting positions or attachment surfaces for one or more balancing weights. If the fitting position is known or can be delimited with respect to its angular position, it can be sufficient to clean a correspondingly reduced circumferential region of the respective cleaning track 10, 12.

The rim cleaning station 2 comprises a frame 14 erected and fastened on the floor, on which frame a conveyor 15, namely a horizontally aligned roller conveyor 16 is arranged with an associated drive motor 17 for the compete wheel 8 to be cleaned. A centering and rotating device 18 for the complete wheel 8 is attached to the frame 14 above the roller conveyor 16. — The centering and rotating device 18 centres the complete wheel 8 brought to lie on the roller conveyor 16 and fixes it in its lateral position during the cleaning process. At the same time, the centering and rotating device 18 can rotate the complete wheel 8 about its own axis. A cleaning device 20 is fastened to the frame 14 below the roller conveyor 16 with a cleaning head 22 whose position can be changed and adjusted. By means of a holding and adjusting — device 24, the cleaning head 22 can engage from below into the rim inner space of the centred complete wheel 8, space enclosed by the rim inner casing, through an associated recess 26 in the roller field 28 of the roller conveyor 16, and there can perform the required cleaning of the rim inside surface 30 on the respective cleaning track 10, 12, as is described in detail further below. In this case, the complete wheel 8 is generally rotated by the centering and rotating — device 18 about its own vertically aligned axis, while the cleaning head 22 is preferably spatially stationary during the actual cleaning and is only moved for a track change or to reach the rest position or a service position (see below).

The centering and rotating device 18 comprises two pairs of rolls 34, 36 with vertical axes of rotation, which are arranged respectively on an arm 38 adjustable or moveable towards the frame 14 by means of associated drive units. Each of the two arms 38 in the example here carries a driven roll 34, whose rotation is transmitted to the complete wheel 8 on contact with the tyre 6, and a roll 36 passively rotating with it. Altogether, the four rolls 34, 36, seen from above at the corners of a square, are located outside the perimeter of the tyre. During the infeeding and outfeeding of the complete wheel 8 into or out of the working position, the distance between the two parallel arms 38 is adjusted so wide that the rolls 34, 36 do not touch the tyre 6 or in any way hinder wheel conveying. To centre and rotate the complete wheel 8, the two arms 38 guided by rails are moved so far together by an adjusting drive, retaining their parallel alignment with respect to each other, that the four rolls 34, 36 are applied with light — pressureagainst the tread 40 of the tyre 6, as described in more detail below (outside centering).

The cleaning device 20 installed below the roller conveyor 16 comprises a cleaning cloth designed as a circumferential belt, which is stowed on an unwinding roller 48 or reel. Similarly to a film reel in a film projector, the unused, clean cleaning belt 44 can be unwound from the unwinding roller 48 by a roller and/or belt drive 46, guided past the cleaning head 22 and finally, generally after gathering dirt particles according to usage, wound onto a winding roller 42 orreel. By appropriate controlling of the roller and/or belt drive 46, the cleaning belt 44 can be moved forward in steps or continuously, so that a clean belt section is always available at the cleaning head 22. The cleaning belt 44 can also be moved forward during rim cleaning with arotating complete wheel 8.

The two rollers 42, 48 and the roller and/or belt drive 46 are components of a relatively bulky cleaning unit 50, from which a cantilever 52 projects upwards, which carries the relatively compact cleaning head 22. The cleaning unit 50 and the cleaning head 22 together form the — cleaning device 20. This spatial division allows the cleaning head 22 to pass without difficulty into the working position through the recess 26 in the roller field 28 of the roller conveyor 16.

In the example here, the two rollers 42, 48 are situated next to each other in an essentially horizontal plane below the cleaning head 22, and the cleaning belt 44 is guided past a cleaning roller 54 of the cleaning head 22 through a system of pulleys 80 (partially visible in FIGS. 7 to — 9) The rim 4 is cleaned by the side of the cleaning belt 44 facing away from the cleaning roller

54. The arrangement of the components can differ in detail. The essential is for the cleaning belt 44 to be pressed against the point on the rim 4 to be cleaned and for it to be moved forward as required.

To adjust the position of the cleaning head 22, the cleaning device 20 is located on the holding and adjusting device 24 to be height-adjustable by means of a lift cylinder 58 (adjusting drive).

In the example here, this is an electric cylinder which has the advantage compared with a pneumatic cylinder of being able to reach not only the target end positions (stops) but any required intermediate position. The guideway is actually determined — depending on the axial — position of the cleaning track 10, 12 — as a function of the wheel type. A rack and pinion drive or a spindle drive is also possible as an alternative. A guide rail 56 arranged parallel to the lift cylinder 58 gives mechanical stability to the linear guide arrangement. The lift cylinder 58 and the guide rail 56 can furthermore pivot towards the vertical alignment about a horizontal axis of rotation inside a vertical plane, such that the cleaning head 22 can pivot back and forth in — the direction of pivot 60 marked by the double arrow (see FIG. 5). The lifting movement and the pivoting movement can be controlled separately from each other (independently). The bearing support 62, on which the lift cylinder 58 and the guide rail 56 are arranged, can travel back and forth along guide rails 64 in the longitudinal direction (X) 66 of the roller conveyor 16 by means of appropriate drive units. An adjustment possibility for the bearing support 62 — by means of associated guide rails 70 and, if necessary, by means of appropriate drive units also exists in the lateral direction (Y) 68 of the roller conveyor 16. As a result, the cleaning device 20 is adjustable laterally (X, Y) and in height (Z) and can additionally pivot or tilt in the direction of pivot 60.

In the example here, there is no drive unit in the lateral direction (Y). This movement is executed manually. In the working position in which the rim 4 is cleaned, the complete cleaning unit is fixed through a locking mechanism in the direction of the guide rail 70. No action is necessary along this axis for the cleaning process. The cleaning unit is only moved onto the guide rails 70 to change the belt, when the cleaning unit must be relocated below the conveyor technology. To do this, an operator manually unlocks the unit and pulls it out.

The described adjustment possibilities, which the holding and adjusting device 24 provides, allows the cleaning head 22, after the complete wheel 8 has been fed in from a rest position (FIG. 2) below the roller conveyor 16, to be moved firstly into a preliminary position (FIG. 3 and detail in FIG. 8) associated with the first (upper in this case) cleaning track 10 on the rim 4 and from there into a working position (FIG. 9) in which the cleaning belt 44 presses against the rim 4. In this working position, the centering and rotating device 18 rotates the complete wheel 8 about its wheel axis 32, such that the complete cleaning track 10 can be cleaned as required in the 360° circumference or a partial section thereof. The cleaning head can then accordingly be turned from the first cleaning track 10 to the second (lower in this case) cleaning track 12 (FIG. 4) and can be returned to the rest position for outfeeding the complete wheel 8 after the end of the cleaning process (corresponding to FIG. 2). It is furthermore possible before performing or after ending a cleaning process, to move the cleaning head 22 into a service position, tilted and situated in the lateral direction 68 outside the frame cross section (FIG. 5, 6 and 7) below the roller conveyor 16, in which position it is more accessible for maintenance work.

The described adjustment mechanism of the holding and adjusting device 24 is a comparatively simple design and completes the necessary adjustment processes rapidly, reliably and efficiently. However, a standard industrial robot or robot arm with multi-axis control could be used in its place for holding and adjusting the cleaning device 20.

The process steps presented above as an overview when operating the rim cleaning station 2 are described in detail below: < A complete wheel 8 (air-filled) is fed into the rim cleaning station 2 by the roller conveyor 16 (FIG. 2). e The complete wheel 8 is held in the gripping region of the centering and rotating device 18. The wheel is then centred by outside centering. To do this, two driven rolls 34 and two rolls 36 rotating with them move sideways onto the tread 40 of the wheel. At the same time, — theroller conveyor 16 is driven in the opposite direction so as to support the rotating movement of the wheel. Due to the rotating movement and the rolls 34, 36 coming together, the wheel is moved centrally and is centred by the conveyor technology. e As soon as the wheel is centred, the cleaning head 22 can be moved into the rim 4. The recess 26 in the roller conveyor 16 is used for this purpose. A preliminary position of the cleaning track to be cleaned is reached (still without contact, see FIGS. 3 and 8). The cleaning tracks 10, 12 to be cleaned of the rim 4 are respectively the two bonding tracks in which the balancing weight will be adhesive bonded after cleaning. e The first cleaning track 10 is then cleaned. To do this, the cleaning head 22 is moved with the cleaning belt 44 to make contact with the rim 4. The wheel is rotated about the wheel axis 32, such that the bonding track of the rim is cleaned in the full circumference (360°) (FIG. 9). e During the cleaning process, it is possible to hold the cleaning belt 44 stationary and therefore to perform the entire cleaning cycle with the least possible belt consumption.

However, in the case of very dirty rims 4, the cleaning belt 44 can be advanced as reguired so — that the cleaning belt 44 is moved relative to the rim 4. Clean cloth or belt is therefore always present on the contact surface and more dirt can be gathered. e A track change takes place after cleaning the first cleaning track 10. The cleaning belt 44 can also be advanced during the track change so that a clean cloth or belt section is present in the new cleaning track 12 (FIG. 4). + Finally, the second cleaning track 12 is cleaned in the full circumference (360*) by the same procedure as the first cleaning track 10. e Once the second cleaning track 12 has been fully cleaned, the cleaning head 22 moves down out of the conveyor technology (roller conveyor 16) and the wheel is fed out (similar to

FIG. 2). + In order to make the cleaning device 20 and in particular the cleaning head 22 accessible to the operator — perhaps to change the cleaning belt 44 when it is used up — a service position is provided. The operator is then able to pull the complete cleaning unit sideways out from below the conveyor technology (FIGS. 5 to 7). — The machine can be used both for full circumferential cleaning of both bonding tracks (360°)

as well as for partial cleaning. For example, when the position of the balancing weight is known beforehand, only the corresponding region needs to be cleaned. The position of the rim cleaning station 2 in the overall installation is decisive in this respect. Depending on the installation position in the line, where the balancing weight is to be adhesive bonded is not yet known at the time of cleaning. The rim 4 must then be cleaned in the full circumference (360°).

If the angle and the length of the balancing weight are however already known, this region alone can be targeted for cleaning.

An electronic controller associated with the rim cleaning station 2, which controller can be — implemented in hardware and/or software, controls the drive unit of the conveyor 15, the centering and rotating device 18, the holding and adjusting device 24 and the roller and/or belt drive 46. Many steps necessarily take place sequentially, perhaps centering the complete wheel 8 after feeding it in. Other steps can be executed advantageously simultaneously or at least partially overlapping in time in order to optimise the total cycle time. For example, the cleaning head 22 can begin to be brought to the preliminary position (FIG. 8) even during the centering process. Similarly, the cleaning belt 44 can be moved forward at the same time as the track change of the cleaning head 22. Finally, the cleaning head 22 can be moved back from the working position to the basic position even during the opening of the gripper formed by the rolls 34, 36. This way, it is feasible to reduce the total cycle time of the rim cleaning station in the event of full circumferential cleaning of two cleaning tracks 10, 12 to 13 seconds or less.

Reference signs list 2 Rim cleaning station 4 Rim 6 Tyre 8 Complete wheel 10 Cleaning track 12 Cleaning track 14 Frame 15 Conveyor

16 Roller conveyor 17 Drive motor 18 Centering and rotating device 20 Cleaning device 22 Cleaning head

24 Holding and adjusting device 26 Recess 28 Roller field 30 Rim inside surface

32 Wheel axis 34 Roll 36 Roll 38 Arm 40 Tread

42 Winding roller 44 Cleaning belt 46 Roller and/or belt drive 48 Unwinding roller 50 Cleaning unit

52 Cantilever 54 Cleaning roller 56 Guide rail 58 Lifting cylinder 60 Direction of pivot

62 Bearing support 64 Guide rail 66 Longitudinal direction 68 Lateral direction 70 Guide rail

80 Pulley

Claims

Patent Claims

1. Rim cleaning station (2) with + conveyor device (15) for transporting a complete wheel (8) with tires (6) and rims (4) in and out, + centering and rotating device (18) for centering and spinning a complete wheel (8) . roller and/or belt drive (46) and control means for guiding the cleaning strip (44) around the cleaning head (22).

2. Rim cleaning station (2) according to claim 1, wherein the winding roller (42), unwinding roller (48) and roller and/or belt drive (46) are — arranged in a cleaning unit (50) from which a boom (52) protrudes, which carry the cleaning head (22).

3. Rim cleaning station (2) according to claim 2, wherein the cleaning head (22) has a cleaning roller (54) for guiding the cleaning strip (44), and wherein the boom (52) must be pneumatically loaded to press the cleaning strip (44) — against the rim (4).

4. — A rim cleaning station (2) according to one of the preceding claims, wherein the cleaning device (20) is mounted on a holding and adjusting device (24) arranged below the conveyor device (15).

5. Rim cleaning station (2) according to claim 4, wherein the holding and - adjusting device (24) enables the cleaning device (20) to move in three spatial directions and turn around at least one axis.

6. — The rim cleaning station (2) according to one of the preceding claims, wherein the conveyor device (15) comprises a roller conveyor (16).

7. Rim cleaning station (2) according to claim 6, wherein — the roller conveyor (16) has a roller field (28) with a recess (26) for the passage of the cleaning head (22).

8. — The rim cleaning station (2) according to one of the preceding patent claims, wherein the centering and rotating device (18) has at least one usable roller (34), which can be pressed against the running surface (40) of the entire wheel (8) with the help of an adjustment drive in order to rotate it.

9. The rim cleaning station (2) according to one of the preceding patent claims, wherein the cleaning strip (44) consists of a textile fabric.

10. A method for cleaning the rim (4) of an entire wheel (8) with rim (4) and ring (6), where in the rim cleaning station (2) according to one of the previous patent claims * the entire wheel (8) is transported in the working position with the help of a conveyor device (15) and is centered in the centering and with the rotating device (18), * the cleaning head (22) is pressed against the rim (4) with the help of the holding and adjusting device (24), and then * the whole wheel (8) is rotated around its axis of rotation (32) with the help of the centering and rotating device (18) the cleaning head (22) being in place so that the cleaning track (10, 12) is cleaned with the rim (4) a full 360* or part of it.

11. The method according to claim 10, where two cleaning tracks (10, 12) on the rim (4) are cleaned one after the other, in which case for track change — the position of the cleaning head (22) is changed with a holding and adjusting device (24).

12. The method according to claim 10 or 11, where before, after and/or during cleaning, the cleaning cloth (44) is advanced with a roller and/or belt drive (46).

13. The method according to one of claims 10-12, where the cleaning — is performed with a dry cleaning strip (44) without liquid wetting.

14. The method according to one of claims 10-13, where in order to reach the maintenance position, the cleaning device (20) is positioned with the holding and adjusting device (24) so that at least the cleaning head (22) is freely accessible.

15. The method according to one of claims 10-14, where the entire — wheel (8) is transported and cleaned in a horizontal plane.