Tire inflation system and method for inflating a tubeless tire with a tire inflation bell having several concentrically arranged tire inflation rings

Abstract

Tire inflation system with a support surface on which a tire assembly consisting of a wheel rim and a tire mounted on the wheel rim can be positioned, with a tire inflation bell (1) arranged above the support surface with an outermost tire inflation ring (5) and at least two inner tire inflation rings (2, 3, 4), wherein the tire inflation rings (2, 3, 4, 5) are arranged concentrically to one another and have different diameters, and the tire inflation rings (2, 3, 4, 5) are movable by means of a lifting device along a normal to the support surface, and with a connecting line (7) which is connected to the tire inflation bell (1) for supplying compressed air, characterized in that the tire inflation rings (2, 3, 4) each have a first metallic sealing surface (110) and a second metallic sealing surface (120), wherein the first metallic sealing surface (110) of an inner tire inflation ring (2, 3,4) can be brought into contact with the second metallic sealing surface (120) of a nearest outer tire inflation ring (3, 4, 5), such that an axially acting metal-to-metal seal can be formed to seal a bell chamber formed by the inner tire inflation ring (2, 3, 4) against compressed air loss to the outside.

Description

[0001] The present invention relates to a tire inflation system according to the preamble of claim 1 and to a method for inflating a tubeless tire using such a tire inflation system.

[0002] It is known to fill tubeless tire assemblies with compressed air using tire inflation bells. The tire assembly consists of a wheel rim and a tire mounted on the wheel rim. The lower side of the tire assembly usually rests sealed on a support surface. Above the upper side of the tire assembly is a tire inflation bell. This bell is lowered for tire inflation and uses an annular edge to push the tire sidewall away from the rim, creating an annular space between the tire sidewall and the wheel rim through which the tire is filled with compressed air. The compressed air flows into the inflation bell and from there via the annular space into the interior of the tire, finally moving the tire sidewall into contact with the rim, closing the annular space. Once the required inflation pressure has been reached, the tire inflation bell is raised.The tire sidewall follows this movement until the tire jumps into its final position on the rim.

[0003] Tire assemblies can have a wide variety of dimensions. Therefore, it is desirable for a tire inflation system to be usable regardless of tire size. It should therefore be able to serve tire assemblies with rims with a diameter between 20 inches and 58 inches.

[0004] To accommodate the different sizes, it is known to use tire inflation systems with concentrically arranged tire inflation rings of different diameters. Such tire inflation systems are described, for example, in documents EP 1 125 772 B1 and DE 198 01 455 A1. A suitable tire inflation ring is selected depending on the size of the wheel rim. This tire inflation ring is used for the tire inflation process and defines a bell chamber, which is supplied with compressed air by a compressed air generating device during the tire inflation process. The bell chamber must be sealed to the outside to prevent the compressed air from escaping uncontrollably.

[0005] Conventionally, radially acting seals in the form of O-rings are used, as in Fig. 2 of the published patent application DE 198 01 455 A1 or also described in DE 199 61 468 A1. Guide rings, which are held in a stationary position and to which the tire inflation rings are displaceably attached, each have a circumferential groove into which the O-ring is inserted. The O-ring rests against an outer side of the tire inflation ring guided on the guide ring and seals the bell chamber to the outside, thus preventing compressed air from escaping. A major disadvantage of this seal is that when the tire inflation ring is moved, it moves vertically along the O-ring, which places high loads on the seal and ultimately leads to rapid wear.

[0006] It is therefore an object of the present invention to provide a tire inflation system for filling a tubeless tire with a tire inflation bell having a plurality of tire inflation rings, in which the sealing of the bell chamber to the outside is particularly simple and durable.

[0007] This object is achieved by a tire inflation system having the features of claim 1 and by a method for inflating a tubeless tire using such a tire inflation system.

[0008] Accordingly, a tire inflation system is provided with a support surface on which a tire assembly consisting of a wheel rim and a tire mounted on the wheel rim can be positioned. The tire inflation system has a tire inflation bell arranged above the support surface, with an outermost tire inflation ring and at least two inner tire inflation rings. The tire inflation rings are arranged concentrically to one another and have different diameters. They can be moved longitudinally to a normal of the support surface by means of a lifting device. The tire inflation system also has a connecting line connected to the tire inflation bell for supplying compressed air.The tire inflation rings each have a first metallic sealing surface and a second metallic sealing surface, wherein the first metallic sealing surface of an inner tire inflation ring can be brought into contact with the second metallic sealing surface of a nearest outer tire inflation ring, such that a metal-to-metal seal can be formed to seal a bell chamber formed by the inner tire inflation ring against compressed air loss to the outside (between the innermost and the nearest outer tire inflation ring). The metal-to-metal seal is particularly wear-resistant and can be produced cost-effectively. The tire inflation rings thus guide each other during movement in the vertical direction and support each other, whereby the tire inflation bell is particularly compact. An empty space is preferably provided between the tire inflation rings, i.e.The tire inflation rings follow one another directly in the radial direction and there are no components in between.

[0009] In a preferred embodiment, the tire inflation rings each have a cylindrical main portion, to which a support ring is connected on an upper side. The support ring protrudes outward beyond the cylindrical main portion in the radial direction to the longitudinal axis of the tire inflation bell and forms the first metallic sealing surface. The underside of the cylindrical main portion is adjoined by an annular rim, which protrudes inward beyond the cylindrical main portion in the radial direction to the longitudinal axis of the tire inflation bell and forms the second metallic sealing surface.

[0010] Preferably, the first annular metallic sealing surface and the second metallic sealing surface are flat and each lie in a plane perpendicular to the longitudinal axis of the tire inflation bell. The seal thus acts exclusively in the axial direction, making it wear-resistant. It can be provided that a circumferential groove is formed in the second metallic sealing surface, in which a sealing ring is seated, which enhances the sealing effect.

[0011] In another variant, the two metallic sealing surfaces can be conical or curved and have a corresponding shape, such that the metal-to-metal seal includes a positive fit. It is advantageous if the second metallic sealing surface is convex and the first metallic sealing surface is concave, so that the selected tire inflation ring can be supported radially on the nearest outer ring and the positive fit is adjustable.

[0012] The tire inflation bell preferably has a cover plate, against the underside of which the tire inflation rings rest sealingly with their upper sides in the starting position, wherein, in a plan view from above, a circular deflection plate is arranged within the inner tire inflation ring below the cover plate, which is designed to deflect compressed air flowing from the connecting line outwards in a radial direction. The compressed air is thus guided outwards in a targeted manner and cannot flow unhindered along the longitudinal axis to the center of the rim. It is preferred if the tire inflation rings have projections on their upper side which can be received in corresponding recesses in the underside of the cover plate to form a positive connection. The projections are preferably curved or conical.

[0013] Preferably, an annular gap is formed in the initial position between the innermost tire inflation ring and the deflector plate, allowing compressed air coming through the connecting line to flow into the space defined by the innermost tire inflation ring. In this case, too, the deflector plate prevents the compressed air from flowing into the center of the rim. Instead, the compressed air flows through the annular gap and along the inside of the innermost tire inflation ring to the annular space between the tire and the wheel rim. Thus, the compressed air flow is directed in a targeted manner.

[0014] Preferably, the tire arrangement rests on the support surface with a bottom side in a sealing manner.

[0015] Furthermore, a method for filling a tubeless tire mounted on a wheel rim by means of a tire filling system is provided, which - a tire inflation bell having an outermost tire inflation ring and at least two further inner tire inflation rings, wherein the tire inflation rings are arranged concentrically to one another and have different diameters, wherein the tire inflation rings each have a first metallic sealing surface and a second metallic sealing surface, and - has at least one connecting line which is connected to the tire inflation bell for supplying compressed air, the method comprising the following steps: a) Selecting a tire inflation ring according to the size of the wheel rim, b) moving the selected tire inflation ring from a starting position to a filling position in which the selected tire inflation ring rests against a side surface of the tire and forms an annular space between the tire and the wheel rim for filling the tire with compressed air and the first metallic sealing surface is at least partially in contact with the second metallic sealing surface of the nearest outer tire inflation ring, c) Moving the nearest outer tire inflation ring upwards and clamping the two metallic sealing surfaces against each other to form a metal-to-metal seal which seals the bell chamber formed by the selected tire inflation ring against compressed air loss to the outside.

[0016] By clamping the metal sealing surfaces, the bell chamber can be effectively sealed against pressure loss to the outside. Preferably, several connecting lines are provided, arranged in the center of the tire inflation bell.

[0017] The tire inflation system is preferably designed as described above.

[0018] A preferred embodiment of the invention is explained in more detail below with reference to the drawing. Fig. 1 shows a longitudinal section through a tire filling bell of a tire filling system, as well as a detailed view of a section.

[0019] Fig. 1 shows a tire inflation bell 1 of a tire inflation system, which is arranged above a support surface (not shown), which can be formed, for example, by a support plate or a conveyor belt, and has four concentrically arranged tire inflation rings 2, 3, 4, 5, which can be moved between a starting position and an inflation position by means of a lifting device (not shown) along a normal perpendicular to the support surface. The tire inflation rings 2, 3, 4, 5 are identical except for their size. The tire inflation rings 2, 3, 4, 5 are arranged evenly spaced in the radial direction relative to the longitudinal axis of the tire inflation bell 100. The spacing is preferably 4.8 inches.

[0020] The tire inflation bell 1 defines a bell chamber 6 that is open at the bottom. The tire inflation rings 2, 3, 4, 5 and their position delimit or define the bell chamber 6. The tire inflation bell 1 is connected at the top via a connecting line 7 and valves (not shown) to a compressed air generating means, e.g., a compressed air tank, which supplies the bell chamber 6 with compressed air.

[0021] In the starting position, the tire inflation rings 2, 3, 4, 5 rest with their upper sides sealingly against the underside of a cover plate 8. In a top view, a circular deflection plate 9 is arranged within the inner tire inflation ring 2 below the cover plate 8. The deflection plate 9 has a central elevation 10 on the upper side that deflects compressed air flowing from the connecting line 7 in a radial direction outwards between the cover plate 8 and the deflection plate 9. In the starting position, an annular gap is provided between the innermost tire inflation ring 2 and the deflection plate 9, through which the compressed air can flow into the space delimited by the innermost tire inflation ring 2.

[0022] To inflate a pneumatic tire of a tire assembly, one of the tire inflation rings 2, 3, 4, 5 is selected, whose diameter matches the outer rim diameter of the tire assembly to be inflated, so that an annular gap exists between the tire inflation ring's inner diameter and the rim's outer diameter. The selected tire inflation ring 4, in the example shown, the second one from the outside, is moved into the inflation position.

[0023] In the inflation position shown, the upper edge of the rim is within the bell chamber, and the tire bead adjacent to the selected tire inflation ring is lifted from the rim by the selected tire inflation ring. The annular gap between the rim and the tire bead allows the compressed air supplied to the bell chamber via the connecting line to enter the annular space defined by the rim and the tire.

[0024] The selected tire inflation ring 4 rests sealingly with a carrier ring 11 on an edge 12 of the nearest outer tire inflation ring 5, so that the compressed air cannot escape to the outside between the selected tire inflation ring 4 and the nearest outer tire inflation ring 5.

[0025] On the left side of the Fig.1 shows details of the sealing of the bell chamber 6. The outer tire inflation ring 5 closest to the selected tire inflation ring 4 is in the starting position. On the upper side 13, the tire inflation rings 5 ​​have conical projections 14 which engage in corresponding recesses 15 in the underside of the cover plate 8 in the starting position, creating a positive fit. The positive fit seals the bell chamber 6 to the outside, and forces acting on the tire inflation ring 5 can be diverted into the cover plate 8 via the positive fit. It can be provided that the tire inflation rings 5 ​​each have a circumferential groove 16 on the upper side 13, into which a sealing ring 17 is inserted, which in the starting position rests against the underside of the cover plate 8 in order to improve the sealing of the bell chamber 6.This sealing device consisting of the groove and the sealing ring acts only in the axial direction parallel to the longitudinal axis of the tire inflation bell 100 and is therefore wear-resistant.

[0026] To further seal the bell chamber 6, the selected tire inflation ring 4 is clamped to the nearest outer tire inflation ring 5 to form a metal-to-metal seal.

[0027] Each tire inflation ring 4, 5 has a cylindrical main region 18, to which the carrier ring 11 adjoins on an upper side. The main region 18 and the carrier ring 11 are coaxially aligned with one another. The outer diameter of the carrier ring 11 is larger than the outer diameter of the cylindrical main region 18, so that the carrier ring 11 protrudes outward and forms a first annular metallic sealing surface 110 on the underside. The first annular metallic sealing surface 110 is flat and lies in a plane perpendicular to the longitudinal axis of the tire inflation bell 100. The first annular metallic sealing surface 110 preferably has a radial width in a range of 15 mm to 25 mm, preferably approximately 20 mm. The previously described conical projections 14 are arranged on the upper side of the carrier ring.The inner diameter of the carrier ring 11 is slightly smaller than the inner diameter of the cylindrical main region 18, so that the carrier ring also protrudes slightly inward. The annular rim 12, which is arranged coaxially to the cylindrical main region 18, adjoins the underside of the cylindrical main region 18. The rim 12 is beveled circumferentially on the outside such that it tapers downwards. In the region of the upper side, the rim 12 has an inner diameter that is smaller than the inner diameter of the cylindrical main region 18, so that a second metallic sealing surface 120 is formed on the upper side. The second annular metallic sealing surface 120 is flat and lies in a plane perpendicular to the longitudinal axis of the tire inflation bell 100. The second annular metallic sealing surface 120 preferably has a radial width in a range of 10 mm to 20 mm, preferably approximately 15 mm.In addition, the outer diameter of the rim 12 is larger than the outer diameter of the main cylindrical portion, so that the rim 12 also protrudes outward. Due to the beveling of the rim 12, the rim 12 has a narrow annular contact surface 121 on its underside, which is designed to be brought into contact with the tire sidewall in the inflation position.

[0028] When the selected tire inflation ring 4 is now moved into the inflation position, the second metallic sealing surface 121 of the nearest outer tire inflation ring 5 is brought into contact with the first metallic sealing surface 110 of the selected tire inflation ring 4. To form a metal-to-metal seal, the inner tire inflation ring 4 is pressed downward and the outer tire inflation ring 5 is moved upward, so that the metallic sealing surfaces are clamped against one another. In the clamped state, inherent movements can also be compensated for without losing the sealing function. Preferably, the inner tire inflation ring 4 presses downward with a force in a range of 350 kN to 450 kN, in particular approximately 400 kN, and the outer tire inflation ring 5 presses upward with a force in a range of 450 kN to 550 kN, in particular approximately 500 kN. This purely metallic seal is free of oil and grease and contains no sealing agents made of non-metallic materials.Since the seal acts in the axial direction, it is wear-free. To increase the sealing effect, it is conceivable that an annular groove could be introduced into the second metal sealing surface, into which a sealing ring could be inserted. The sealing device formed by the groove and the sealing ring improves the sealing of the bell chamber to the outside. Since the sealing ring is only subjected to axial load, wear is also avoided.

[0029] It can also be provided that the metallic sealing surfaces are conical or curved. The first metallic sealing surface and the second metallic sealing surface have a corresponding shape to form a flat contact surface. It is advantageous if the second metallic sealing surface is convex and the first metallic sealing surface is concave, so that the selected tire inflation ring can be supported radially on the nearest outer ring and the positive locking is adjustable.

Claims

[1] Tire inflation system with a support surface on which a tire assembly consisting of a wheel rim and a tire mounted on the wheel rim can be positioned, with a tire inflation bell (1) arranged above the support surface with an outermost tire inflation ring (5) and at least two inner tire inflation rings (2, 3, 4), wherein the tire inflation rings (2, 3, 4, 5) are arranged concentrically to one another and have different diameters, and the tire inflation rings (2, 3, 4, 5) are movable by means of a lifting device along a normal to the support surface, and with a connecting line (7) which is connected to the tire inflation bell (1) for supplying compressed air, characterized byin that the tire filling rings (2, 3, 4) each have a first metallic sealing surface (110) and a second metallic sealing surface (120), wherein the first metallic sealing surface (110) of an inner tire filling ring (2, 3, 4) can be brought into contact with the second metallic sealing surface (120) of a nearest outer tire filling ring (3, 4, 5) in such a way that a metal-to-metal seal acting in the axial direction can be formed for sealing a bell chamber formed by the inner tire filling ring (2, 3, 4) against compressed air loss to the outside. [2] Tire inflation system according to claim 1, characterized bythat the tire filling rings (4, 5) each have a cylindrical main region (18), to which a support ring (11) is connected on an upper side, which projects outwards beyond the cylindrical main region (18) in the radial direction to the longitudinal axis of the tire filling bell (100) and forms the first metallic sealing surface (110), and that on the underside of the cylindrical main region (18) there is connected an annular rim (12) which projects inwards beyond the cylindrical main region (18) in the radial direction to the longitudinal axis of the tire filling bell (100) and forms the second metallic sealing surface (120). [3] Tire inflation system according to claim 2, characterized by that the first annular metallic sealing surface (110) and the second metallic sealing surface (120) are flat and each lie in a plane perpendicular to the longitudinal axis of the tire inflation bell (100). [4] Tire filling system according to one of the preceding claims, characterized bythat a circumferential groove is introduced into the second metallic sealing surface (120) in which a sealing ring is seated. [5] Tire inflation system according to claim 1 or 2, characterized by that the two metallic sealing surfaces (110,120) are conical or curved and have a corresponding shape, such that the metal-to-metal seal includes a positive connection. [6] Tire filling system according to one of the preceding claims, characterized by that the tire inflation bell (1) has a cover plate (8), on the underside of which, in the starting position, the tire inflation rings (2, 3, 4, 5) rest sealingly with their upper sides, and that in a plan view from above, within the inner tire inflation ring (2) below the cover plate (8), a circular deflection plate (9) is arranged, which is designed to deflect compressed air flowing from the connecting line (7) in a radial direction outwards. [7] Tire inflation system according to claim 6, characterized bythat the tire filling rings (2,3,4,5) have projections (14) on their upper side which can be received in corresponding recesses in the underside of the cover plate (8). [8] Tire inflation system according to claim 6 or 7, characterized by that in the starting position an annular gap is formed between the innermost tire filling ring (2) and the deflection plate (9) such that compressed air coming through the connecting line (7) flows into the space delimited by the innermost tire filling ring (2). [9] Tire filling system according to one of the preceding claims, characterized by that the tire arrangement rests on the support surface with a sealing underside. [10] Method for filling a tubeless tyre mounted on a wheel rim by means of a tyre filling system comprising - a tire inflation bell (1) having an outermost tire inflation ring (5) and at least two further inner tire inflation rings (2, 3, 4), wherein the tire inflation rings (2, 3, 4, 5) are arranged concentrically to one another and have different diameters, wherein the tire inflation rings (2, 3, 4, 5) each have a first metallic sealing surface (110) and a second metallic sealing surface (120), and - at least one connecting line (7) connected to the tire inflation bell (1) for supplying compressed air, the method comprising the following steps: a) Selecting a tire inflation ring (2,3,4) according to a size of the wheel rim, b) moving the selected tire inflation ring (4) from a starting position to a filling position in which the selected tire inflation ring (4) rests against a side surface of the tire and forms an annular space between the tire and the wheel rim for filling the tire with compressed air and the first metallic sealing surface of the selected tire inflation ring (110) is at least partially in contact with the second metallic sealing surface (120) of the nearest outer tire inflation ring (5), c) Moving the nearest outer tire inflation ring (5) upwards and in the axial direction, clamping the two metallic sealing surfaces (110, 120) against each other to form a metal-to-metal seal acting in the axial direction, which seals the bell chamber formed by the selected tire inflation ring (4) against compressed air loss to the outside. [11] Method according to claim 10, characterized bythat the tire filling rings (2, 3, 4, 5) each have a cylindrical main region (18), to which a support ring (11) is connected on an upper side, which projects outwards beyond the cylindrical main region (18) in the radial direction to the longitudinal axis of the tire filling bell (100) and forms the first metallic sealing surface (110), and that on the underside of the cylindrical main region (18) there is connected an annular rim (12) which projects inwards beyond the cylindrical main region (18) in the radial direction to the longitudinal axis of the tire filling bell (100) and forms the second metallic sealing surface (120). [12] Method according to claim 10 or 11, characterized by that the first annular metallic sealing surface (110) and the second metallic sealing surface (120) are flat and each lie in a plane perpendicular to the longitudinal axis of the tire inflation bell (100). [13] Method according to one of the preceding claims 10 to 12, characterized bythat a circumferential groove is introduced into the second metallic sealing surface (120) in which a sealing ring is seated. [14] Method according to claim 10 or 11, characterized by that the two metallic sealing surfaces (110,120) are conical or curved and have a corresponding shape, such that a positive connection is produced in process step c).

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