Method for mounting a vehicle tire on a rim

Abstract

A method for mounting a vehicle tire (8) on a rim (6) using a rim clamping device (1) with at least two support tables (5), comprising the following method steps: a. Horizontal clamping of the rim (6) in a rim clamping device (1), b. Placing the vehicle tire (8) onto the rim (6) from above, c. Pressing a lower tire bead (14) into a rim bed (9) of the rim (6) using a mounting tool (13), characterized in that the method comprises the following further method steps: d. Moving at least two support tables (5) into a first position, wherein the at least two support tables (5) each have a top side and in the first position the top sides lie in a common horizontal plane, e.Pressing the upper tire bead (10) below an upper rim flange (11) of the rim using the mounting tool (13) and at least one hold-down device (15,16) while supporting the vehicle tire (8) by means of the upper surfaces of the at least two support tables (5).

Description

The present invention relates to a method for mounting a vehicle tire on a rim with the features of the preamble of claim 1. Rim clamping devices are part of tire mounting machines used to mount tubeless tires onto rims. The rim is firmly clamped and fixed in position within the rim clamping device. In the tire mounting machine, the tire is mounted onto the rim by first pressing the lower tire bead over the upper rim flange. To achieve this, the rim is held stationary relative to a moving mounting tool. This tool travels at a fixed distance from the rim along the circumference of the stationary rim, pressing the lower tire bead radially outward over the upper rim flange. Then, the upper (second) tire bead is pressed radially over the upper rim flange using the moving mounting tool.To ensure the tire's position and orientation can be monitored during the mounting of the second tire bead, the tire must be supported on its underside. Traditionally, non-height-adjustable support surfaces are used for this purpose. Mounting the second bead without underside support is also common, but requires tire-specific process adjustments and is not possible with all tire types that can be mounted on drop-center rims. German patent application DE 10 2019 132 287 A1 discloses a device for clamping a rim of a vehicle wheel, wherein the device comprises movable clamping elements with clamping arms and support elements, and a rim flange of the rim can be placed on the support surfaces. The patent application EP 2 599 649 A1 discloses a method for mounting a tire on a rim, wherein the tire is exposed downwards during the mounting of the upper tire bead. The object of the present invention is to provide an alternative method for mounting a vehicle tire on a rim. This problem is solved by a method for mounting a vehicle tire on a rim with the features of claim 1. For the purpose of geometrically describing the assembly, the axis of rotation of the rim to be clamped is assumed to be the longitudinal axis of the device. With respect to the longitudinal axis, a radial direction is specified, indicating the distance from the longitudinal axis, as well as a circumferential direction, which is tangential to a specific radius arranged radially. The rim clamping device is designed to be placed on a floor. Therefore, sides furthest from the floor are described as tops and sides closest to the floor as bottoms. Accordingly, a method for mounting a vehicle tire on a rim using a rim clamping device with at least two support tables is provided, wherein the method comprises the following steps: a. Horizontal clamping of the rim in a rim clamping device, b. Placing the vehicle tire onto the rim from above, c. Pressing a lower tire bead into a rim well of the rim using a mounting tool, d. Moving at least two support tables into a first position, wherein the at least two support tables each have a top surface and the top surfaces lie in a common horizontal plane, e. Pressing the upper tire bead below an upper rim flange of the rim using the mounting tool and at least one hold-down device, while supporting the vehicle tire by means of the top surfaces of the at least two support tables. The at least two support tables, preferably at least three, and in particular exactly three, support the vehicle tire during the mounting of the upper tire bead. This prevents the tire from shifting downwards and provides targeted support. This prevents the tire from becoming misaligned. Furthermore, supporting the tire downwards allows for the mounting of the upper tire bead even with a partially radially gripped tire. The mounting process can be better controlled and therefore requires fewer adjustments for different tire types. Preferably, the following process steps are carried out after process step e.: f. Lowering the at least two support tables and thereby releasing the vehicle tire with the rim clamped in place, g. Raising the at least two support tables to a second position, wherein the at least two support tables lie with their upper surfaces in a common horizontal plane, and the vehicle tire rests on the upper surfaces of the at least two support tables. In process step f, the vehicle tire centers itself on the tire seat of the rim. In process step g, the tire is lifted again so that it lies horizontally and centrally to the rim. In a preferred embodiment, the vehicle tire is gripped by a tire gripper in process steps a. to e. After process step g., the vehicle tire is gripped again for further transport. The tire gripper ensures that the relative position of the vehicle tire to the rim from step g. is maintained during transport. Preferably, in process step e., two hold-down devices press down from above onto a tire sidewall of the vehicle tire. Two hold-down devices have the advantage that the vehicle tire is not subjected to excessive deformation stress. In a preferred embodiment, in process step e., the mounting tool moves along the circumference of the upper tire bead and pushes the upper tire bead radially outwards, causing it to move below the upper rim flange, wherein a first detent of the two detents at a first position on the circumference of the upper tire bead pushes the tire sidewall downwards after the mounting tool has moved past this first position, and wherein a second detent at a second position on the circumference of the upper tire bead, which is spaced apart from the first position and is passed by the mounting tool in time after the first position, pushes the tire sidewall downwards and pushes it radially inwards after the mounting tool has moved past the second position. Preferably, the second detent is raised after a defined rotation angle of the mounting tool, whereby the second detent continues to press down on the tire sidewall from above in the raised position, thus preventing strong unwanted deformation of the tire bead or bead core. Preferably, in process step e., the tire gripper relaxes the tire in sections depending on the rotation angle of the mounting tool. This prevents the tire from moving uncontrollably. However, the movements of the tire required for mounting the upper tire bead are supported. Preferably, the method according to process step e. comprises the following steps: - Gripping the vehicle tire with a tire gripper, - Releasing the rim in the rim clamping device, - Gripping the rim from above with a rim gripper, - Moving a centered tire assembly formed from the rim and vehicle tire to a tire filling station. This sequence allows the centering of the tire arrangement to be maintained even during transport to the tire filling station. The rim clamping device is preferably designed to mount vehicle tires on rims with a diameter between 15 and 58 inches. The method is generally applicable to all rim outer diameter sizes within this range. Preferably, the vehicle tires are tubeless. A preferred embodiment of the invention is explained in more detail below with reference to the drawings. Similar or functionally equivalent components are designated by the same reference numerals in the figures. The figures show: Fig. 1: a three-dimensional view of a rim clamping device with support tables in an upper position, with the vehicle tire in section; Fig. 2: a three-dimensional view of the rim clamping device of Fig. 1 with the support tables in a lower position with the tire assembly mounted; and Fig. 3: a three-dimensional view of the rim clamping device of Fig. 1 with the support tables in an upper position for horizontal alignment of the tire with the tire assembly mounted. Fig. 1 shows a rim clamping device 1 of a tire mounting device used for mounting a vehicle tire onto a rim. To describe the process, the device will first be briefly explained. The rim clamping unit 1 has exactly three slides 2 spaced uniformly apart from each other in the circumferential direction, each with a radially movable clamping jaw 3 and a support surface 4. Each slide 2 also has a support table 5, which is arranged radially outward behind the clamping jaws 3. The support tables 5 are longitudinally and vertically movable. During mounting, the rim 6 is placed onto the support surfaces of the slides 4, which are arranged radially in front of the clamping jaws 3. The slides 2 with the clamping jaws 3 then move radially inward and clamp the rim 6, as shown in Fig. 1.The slide 2 is moved by means of pressure-limited hydraulic pistons or force-limited electrically driven spindles. The kinematics of the slide 2 are preferably designed such that both the clamping jaws 3 with the support surfaces 4 for the rim are movable in the radial direction and the support tables 5 are movable in the axial direction. However, it is also conceivable that the support tables 5 are not part of the slide 2 and are therefore movable separately. The clamping jaws 3 engage the lower rim flange 7 of the rim 6 and fix the rim 6 in its position. After the rim 6 is clamped, a vehicle tire 8 is placed on the rim 6 so that the vehicle tire 8 lies on one side in the rim well 9 and on the other side with its lower tire bead 14 above the upper rim flange 11. The placement is carried out using a tire gripper 12, which has several arms that are brought into contact with the tread of the vehicle tire and clamp it from the outside.A mounting arm of a tire mounting tool 13 with a spherically shaped finger then moves over the top of the upper rim flange 11 and presses the lower tire bead 14 radially along the circumference over the upper rim flange 11 (not shown). The rim 6 remains stationary and does not rotate. The underside of the vehicle tire 8 does not rest on the support surfaces of the support tables 5. After the lower tire bead 14 has been mounted, the vehicle tire 8 is lowered by means of the tire gripper 12. In the next step, the support tables 5 are raised synchronously to the same height. In this position, the upper surfaces of the support tables 5 lie in a common horizontal plane. Then, as shown in Fig. 1, the second, upper tire bead 10 is pressed under the upper rim flange 11.The finger of the mounting arm moves at a constant radial distance to the rim 6 and pushes the upper tire bead 10 radially outward, causing it to enter the drop center 9 under the upper rim flange 11. During this process, the vehicle tire 8 rests on the support tables 5, as shown in Fig. 1. The support tables 5 thus prevent the vehicle tire 8 from tilting during the mounting of the upper tire bead 10. Two hold-down devices 15, 16 are used to press down and hold the upper tire bead 10. The two hold-down devices 15, 16 press the tire 8 downwards sufficiently so that it enters the drop center 9 during the mounting of the upper tire bead 10 and remains there. The mounting tool 13 moves along the circumference of the upper tire bead 10, pushing it radially outward.A first of the two hold-down devices 15 presses the tire sidewall downwards at a first position along the circumference after the mounting tool 13 has passed this first position. A second hold-down device 16 presses the tire sidewall downwards at a second position along the circumference, which is spaced apart from the first position and is passed by the mounting tool 13 after the first position, and additionally pushes the tire sidewall radially inwards after the mounting tool 13 has passed the second position. The two hold-down devices 15, 16 ensure that the upper tire bead enters the drop center 9 reliably and is held there, and that the force exerted on the tire bead does not become too great. This ensures that steel strips inserted into the bead core of the tire 8 are not damaged.To optimally control the radial movement of the tire during the mounting of the upper tire bead, the two arms of the tire gripper 12 opposite the clamps 15, 16 are released first, depending on the rotation angle of the mounting tool 13, followed by the release of the remaining two arms of the tire gripper 12. After a predefined time interval or at a predefined position along the circumference of the mounting tool 13, the second clamp 16 is raised, with the second clamp 16 continuing to press down on the tire sidewall from above in the raised position. The mounting tool 13 is positioned approximately 180° offset from the second clamp 16. Raising the second clamp 16 minimizes deformation of the vehicle tire 8 caused by pressure on the tire sidewall.At the end of the mounting of the upper tire bead 10, the vehicle tire 8 is fully released and both the mounting tool 13 and the hold-downs 15,16 are lifted and moved out of the area of ​​the tire assembly. Once the upper tire bead 10 is pressed over the upper rim flange, the support tables 5 are moved downwards synchronously, releasing the tire 8 downwards. This state is shown in Fig. 2. Only the rim 6 is held by the clamping jaws 3, so that the vehicle tire 8, by its own weight, settles onto the rim 6 and centers itself on the rim 6. The lower tire bead 14 rests on the lower rim shoulder. To ensure that the vehicle tire 8 lies in a horizontal plane, in a subsequent process step the support tables 5 are brought into contact with the underside of the vehicle tire 8, with their upper surfaces lying in a common horizontal plane that defines the position of the vehicle tire 8. This state is shown in Fig. 3 and is the final state of mounting the tire 8 on the rim 6. After this mounting step, the centered tire assembly can be lifted, with the vehicle tire 8 first being gripped again by the tire gripper 12, and then the rim 6, released by the rim clamping device 1, being gripped from above by a rim gripper (not shown), so that the tire assembly, while maintaining its centered position, can be transferred to a tire inflation station, which inflates the tubeless tire.

Claims

A method for mounting a vehicle tire (8) on a rim (6) using a rim clamping device (1) with at least two support tables (5), comprising the following method steps: a. Horizontal clamping of the rim (6) in a rim clamping device (1), b. Placing the vehicle tire (8) onto the rim (6) from above, c. Pressing a lower tire bead (14) into a rim bed (9) of the rim (6) using a mounting tool (13), characterized in that the method comprises the following further method steps: d. Moving at least two support tables (5) into a first position, wherein the at least two support tables (5) each have a top side and in the first position the top sides lie in a common horizontal plane, e.Pressing the upper tire bead (10) below an upper rim flange (11) of the rim using the mounting tool (13) and at least one hold-down device (15,16) while supporting the vehicle tire (8) by means of the upper surfaces of the at least two support tables (5). The method according to claim 1, characterized in that the following method steps follow method step e): f. Lowering the at least two support tables (5) and thereby releasing the vehicle tire (8) with the rim (6) clamped in place, g. Raising the at least two support tables (5) to a second position, wherein the at least two support tables (5) have their upper surfaces in a common horizontal plane, and the vehicle tire (8) rests on the upper surfaces of the at least two support tables (5). Method according to claim 2, characterized in that in process steps a. to e. the vehicle tire (8) is gripped by a tire gripper (12) and that after process step g. the vehicle tire (8) is gripped again by the tire gripper (12) for further transport. Method according to one of the preceding claims, characterized in that in method step e) two hold-down devices (15, 16) press down from above onto a tire sidewall of the vehicle tire (8). The method according to claim 4, characterized in that in method step e) the mounting tool (13) moves along the circumference of the upper tire bead (10), thereby pushing the upper tire bead (10) outwards in the radial direction, so that the tire bead (10) moves below the upper rim flange (11), wherein a first hold-down device (15) of the two hold-down devices (15, 16) at a first position along the circumference pushes the tire sidewall downwards after the mounting tool (13) has moved past this first position, and wherein a second hold-down device (16) at a second position along the circumference, which is spaced apart from the first position and is passed by the mounting tool (13) in time after the first position, pushes the tire sidewall downwards and pushes it inwards in the radial direction after the mounting tool (13) has moved past the second position. Method according to claim 5, characterized in that the second hold-down device (16) is raised after a defined rotation angle of the mounting tool (13), wherein the second hold-down device (16) presses down on the tire sidewall from above in the raised position. Method according to one of claims 3 to 6, characterized in that the tire gripper in method step e. relaxes the tire in certain areas depending on the rotation angle of the mounting tool (13). Method according to one of the preceding claims, characterized in that the method according to method step g. comprises the following steps: - gripping the vehicle tire (8) with a tire gripper (12), - releasing the rim (6) in the rim clamping device (1), - gripping the rim (6) with a rim gripper from above, - moving a centered tire assembly formed from rim (6) and vehicle tire (8) to a tire filling station.

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