JP7796235B2 - Application unit for applying a continuous strip to a drum, tire building apparatus and method - Google Patents

Description

Related to an application unit, a tire building apparatus, and a method for applying a continuous strip to a drum.

WO 2022/177421 A1 discloses an application unit, a tire building apparatus, and a method for applying a continuous strip to a drum, in which the application unit includes an application roller having a roller body rotatable about a roll axis, and applies the continuous strip to the drum in an application direction perpendicular to the roll axis. The application roller is provided with holding elements in the form of suction holes distributed throughout the roller body, which hold the continuous strip to the roller body by suction.

A drawback of the application roller disclosed in WO 2022/177421 A1 is that suction alone has proven insufficient to securely hold the continuous strip on the application roller. In particular, the leading edge of the continuous strip tends to continue in a straight line rather than being sucked onto the application roller by the suction openings in the holding surface. If the leading edge is not securely held, the position of the leading edge on the application roller becomes unclear, which can result in inaccurate application of the leading edge, and possibly the entire continuous strip, to the drum, or even failure to apply the coating at all.

The object of the present invention is to provide an application unit, a tire manufacturing apparatus, and a method for applying a continuous strip to a drum that can improve the accuracy of applying the strip to the drum.

According to a first aspect, the present invention provides an application unit for applying a continuous strip to a drum, the application unit comprising an application roll having a roller body rotatable about a roll axis and defining a holding surface extending circumferentially around the roll axis, the application unit further comprising a holding member for holding the continuous strip in a holding position on the holding surface, the holding member being arranged to follow the continuous strip in the holding position on the holding surface along a holding arc of at least 10 degrees around the roll axis as the roller body rotates about the roll axis.

By using the retaining members to hold the continuous strip from the outside on the holding surface at a holding position, the application roll can more securely hold the continuous strip by suction, particularly at its leading end. As the roller body rotates, the retaining members follow the continuous strip in the holding position on the holding surface, thereby more securely holding the continuous strip on the application roll during at least a portion of the roller body's rotation. In particular, if the suction ports are not yet connected to the vacuum source initially, the retaining members can hold the continuous strip on the holding surface until the continuous strip is rotated to a position where each suction port is connected to the vacuum source. In this way, the continuous strip can be held by either the retaining members, the suction ports, or both, in accordance with the principle of never letting go of the continuous strip. As a result, the continuous strip is more accurately received, positioned, and/or held in place on the application roll. As a result, the continuous strip is more accurately applied to the drum.

The retention arc is preferably at least 20 degrees, preferably at least 30 degrees. The longer the retention arc, the longer the length over which the continuous strip can be securely held on the application roller body.

In yet another embodiment, the application unit includes a drive mechanism for moving the holding member along the holding arc, thereby allowing the movement of the holding member to be controlled and/or automated.

Preferably, the drive mechanism is configured to move the holding member away from the holding surface after moving the holding member along the holding arc, thereby allowing the holding member to provide space for subsequent interaction between the application roll and the drum.

In a further embodiment, the drive mechanism includes a first drive unit and a second drive unit that move the holding member along the holding arc, with the holding member moving with a first vector component in a first drive direction and a second vector component in a second drive direction, respectively. Combining the two vector components can generate complex movements of the holding member along a curvature that matches the holding arc.

Preferably, the first drive is arranged to move the holding member in a first drive direction over a first stroke, the first stroke terminating short of a mid-plane that is coincident with the roll axis and extends perpendicular to the first drive direction. Movement of the holding member can therefore be limited to a position along the upper half of the applicator roll. This is the side of the applicator roll where the continuous strip is initially fed from the extruder, and also the side of the applicator roll where the continuous strip is transferred from the applicator roll to the drum. Therefore, it is sufficient for the holding member to only move along this portion of the applicator roll.

In yet another embodiment, the second drive is arranged to move the retaining member only in a second drive direction away from the retaining surface when the retaining member reaches the end of the first stroke. Thus, the retaining member can be moved away from the applicator roll to provide space for subsequent interaction between the applicator roll and the drum.

In a further embodiment, the first drive direction is perpendicular to the roll axis, in other words, the holding member is movable in a plane perpendicular to the roll axis.

In a further embodiment, the first drive direction is vertical or substantially vertical. Thus, the holding member can approach the applicator roll with at least a vertical vector component.

In a further embodiment, the first drive unit and/or the second drive unit comprise a linear drive unit, preferably a pneumatic cylinder. The linear drive unit, in particular the pneumatic cylinder, can be controlled to move the holding member with at least a vector component in the respective drive direction, when the holding member has a degree of freedom of movement relative to the application roll.

In a further embodiment, the holding member comprises fingers, pressure rolls, or pressure conveyors that contact the continuous strip at a holding position while following the continuous strip along the holding arc. The fingers, pressure rolls, or pressure conveyors can physically contact the continuous strip while following the continuous strip along the holding arc, either by moving the entire finger or pressure roller along the holding arc, or by designing the infinite contact surface of the pressure conveyor to span at least the holding arc.

In a further embodiment, the retaining member comprises a contact surface that contacts the continuous strip at a retaining location on the retaining surface, the contact surface extending at an oblique contact angle relative to the first drive direction. The oblique contact angle can be selected to ensure that the retaining member adequately and/or reliably contacts the continuous strip at both the start and end of the retaining arc.

In another embodiment, the application unit is further provided with a peeling element for peeling the continuous strip from the holding member. The peeling element can prevent the continuous strip from remaining stuck to the holding member when the holding member moves away from the application roll at the end of the holding arc.

Preferably, the separating element is a blow-off groove provided in the holding member. In this way, the continuous strip is effectively separated from the holding member and/or blown back onto the applicator roll when pulled together with the holding member in the second drive direction.

In another embodiment, the applicator roll further includes a plurality of suction ports in the roller body to hold the continuous strip against the holding surface by suction.
In another embodiment, the roller body is annular and the application roller further comprises an inner member concentrically disposed within the roller body, the roller body being rotatable circumferentially around the inner member, the inner member comprising a first chamber in communication with a plurality of suction ports at a first circumferential cross section of the roller body, the first chamber being connectable to a vacuum source that holds the continuous strip against a holding surface at the first circumferential cross section.

Preferably, the holding arc at least partially overlaps the first circumferential cross-section. In particular, the holding arc overlaps the first circumferential cross-section by at least 80%. Thus, the continuous strip can be held by the holding member along at least a portion of the circumferential cross-section of the applicator roll, which holds the continuous strip by suction.

In a further embodiment, the inner member includes a second chamber in communication with the plurality of suction ports at the second circumferential cross section of the roller body, the second chamber being connectable to a compressed air source for blowing the continuous strip off the holding surface at the second circumferential cross section. In this manner, the continuous strip can be blown off the holding surface, effectively transferring the continuous strip from the application roll to the drum.

Preferably, the retention arc terminates before or at the second circumferential cross section. Therefore, the retention member does not interfere with blowing or unnecessarily press the continuous strip against the applicator roll at a location where the continuous strip should ultimately be pulled away from the applicator roll.

According to a second aspect, the present invention provides a tire building apparatus for applying a continuous strip to a drum, the tire building apparatus comprising an application unit according to any one of the embodiments of the first aspect of the present invention, the tire building apparatus further comprising an extruder that continuously extrudes the continuous strip onto an application roll, and a drum that continuously receives the continuous strip from the application roll.

The tire building apparatus is equipped with an application unit according to the first aspect of the present invention and therefore has similar technical advantages, which will not be repeated below.

According to a third aspect of the present invention, there is provided a method for applying a continuous strip to a drum using an application unit according to any one of the embodiments of the first aspect of the present invention, the method comprising the steps of:
Rotating the applicator roll about its axis while holding the continuous strip on the holding surface by suction.
A step of holding the continuous strip at a holding position on the holding surface with the holding member while causing the holding member to follow the continuous strip to the holding position on the holding surface along a holding arc as the roller body rotates about the roll axis.

This method relates to the actual implementation of the application unit according to the first aspect of the present invention and therefore has similar technical advantages, although it will not be repeated below.

In a preferred embodiment, the method further comprises the following steps:
Moving the holding member away from the holding surface after moving the holding member along the holding arc.

In a further embodiment, the method further comprises the following steps:
After moving the retaining member along the retaining arc, the continuous strip is separated from the retaining member.

In a further embodiment, the method further comprises the following steps:
continuously extruding a continuous strip onto an application roll; and
Continuously applying the continuous strip onto the drum with an application roll.

In the context of this invention, the term "continuous" is used to indicate a continuous process using a continuous strip that is continuously extruded, coated, and wrapped around the drum several times without cutting the continuous strip to length before each wrap. As a result, the length of the continuous strip exceeds the circumference of the drum and/or coating roll.

In a further embodiment, the continuous strip has a leading edge, and the continuous strip is held in a holding position on a holding surface at the leading edge. As previously mentioned, the leading edge may tend to continue in a straight line rather than being held to the applicator roll by suction. Therefore, using a holding member to hold the leading edge can significantly improve the accuracy with which the leading edge, and the remainder of the continuous strip following the leading edge, is applied to the drum.

According to a fourth, unclaimed aspect, the present invention provides an application unit for applying a continuous strip to a drum, the application unit comprising an application roll rotatable about a roll axis and having a roller body defining a holding surface extending circumferentially about the roll axis, the application unit further comprising a holding member for holding the continuous strip in a holding position on the holding surface, the holding member being provided with an infinite contact surface, in particular an endless belt, for contacting the continuous strip along a holding arc of at least 10 degrees about the roll axis as the roller body rotates about the roll axis.

The application unit according to the fourth aspect of the present invention has substantially the same technical advantages as the application units described above. Furthermore, the application unit according to the fourth aspect of the present invention may be combined, mutatis mutandis, with any feature or embodiment according to the previous aspects of the present invention.

In one embodiment, the retaining member is a hugger belt.

In a further embodiment, the infinite contact surface is actively driven at the same or substantially the same speed as the continuous strip. Alternatively, the infinite contact surface moves passively as a result of friction between the continuous strip and the infinite contact surface.

The various aspects and features described and illustrated in this specification may, to the extent possible, be applied individually. These individual aspects, particularly those described in the accompanying dependent claims, may be the subject of divisional patent applications.

The present invention will now be described based on exemplary embodiments shown in the accompanying schematic drawings.

Figures 1-6 are side views of a tire building apparatus according to a first embodiment of the present invention, illustrating steps in a method for applying strip onto a drum using the tire building apparatus.

Figure 7 is a side view of an alternative tire building apparatus according to a second embodiment of the present invention, illustrating steps in a method for applying strip onto a drum using the alternative tire building apparatus.

Detailed Description of the Invention

FIG. 1 shows a tire building apparatus 1 for applying a continuous strip 9 to a drum 8 according to a first embodiment of the invention.
In this example, the continuous strip 9 is used to wrap a tire component (not shown) around the drum 8. Thus, the drum 8 may be a strip winding drum. In strip winding, the continuous strip 9 is wrapped around the drum 8 multiple times to form layers of the tire component, thereby gradually increasing the cross section of the tire component. The continuous strip 9 comprises or consists of an elastomeric material, in particular rubber.

In the present invention, the term "continuous strip" is used to refer to a strip of sufficient length to allow the continuous strip to be continuously applied and wrapped around the drum 8 several times without cutting the continuous strip 9 to a predetermined length before each wrap. Thus, the length of the continuous strip 9 exceeds the circumference of the drum 8.

The tire building apparatus 1 includes an extruder 2 that continuously extrudes a continuous strip 9, and an application unit 3 that continuously applies the continuous strip 9 to a drum 8. In this example, the drum 8 is also considered to be part of the tire building apparatus 1. The drum 8 continuously receives the continuous strip 9 from the application unit 3.

As further shown in Figure 1, the application unit 3 includes an application roller or roll 4. The application roll 4 includes a roller body 40. The roller body 40 is rotatable about a roll axis X. In this example, the roller body 40 is annular or ring-shaped. The roller body 40 defines a support surface that extends in a circumferential direction C about the roll axis X. The circumference of the support surface is significantly smaller than the circumference of the drum 8.

The applicator roll 4 further includes a plurality of suction openings or ports 42 in the roller body 40 for holding the continuous strip 9 against the holding surface by suction.

The application roll 4 further includes an inner member 43 concentrically arranged inside the roller body 40. The roller body 40 is rotatable around the inner member 43 in the circumferential direction C. The inner member 43 remains stationary and/or is fixed about the roll axis X.

The inner member 43 includes a first chamber 44 in communication with a group of suction ports 42 at the first circumferential cross section E1 of the roller body 40. The first chamber 44 is connectable to a vacuum or reduced pressure source that holds the continuous strip 9 against a holding surface at the first circumferential cross section E1.

The inner member 43 further comprises a second chamber 45 in communication with the group of suction ports 42 at the second circumferential cross section E2 of the roller body 40. The second chamber 45 is connectable to a source of compressed air for blowing the continuous strip 9 off the holding surface at the second circumferential section E2.

The aforementioned applicator roll 4 includes a roller body 40, a holding surface, a suction port 42, an inner body 43, and chambers 44, 45, and is similar or identical to the applicator roll and corresponding parts disclosed in WO 2022/177421.

2, the application unit 3 further comprises a pressing or holding member 5 for pressing and/or holding the continuous strip 9 at a holding position P on the holding surface. In this example, the holding member 5 is formed as a block or finger for passively contacting the continuous strip 9. Alternatively, a pressing roller may be used.

2 and 3, the retaining member 5 is positioned to move, track, or follow the continuous strip 9 at a retaining position P on the retaining surface along a retaining arc A about the roller axis X. The retaining arc A begins at an angular position where the retaining member 5 first contacts the continuous strip 9, as shown in FIG. 2, and ends at an angular position about the roller axis X where the retaining member 5 disengages, releases, or pulls away from the continuous strip 9, as shown in FIG. 4. In this example, the retaining arc A extends over 40 degrees along or around the roller axis X.

In particular, the retaining arc A overlaps at least partially, e.g., by at least 80% or more, with the first circumferential cross section E1. Furthermore, in this example, the retaining arc A terminates before or at the second circumferential cross section E2.

1 , the holding member 5 includes a finger body or finger tip 50 with a contact surface 51 that contacts the continuous strip 9 at a holding position P on the holding surface. In this example, the contact surface 51 extends at an oblique contact angle H relative to the vertical plane. In particular, the oblique contact angle H is selected to ensure that the contact surface 51 contacts the continuous strip 9 at both the start and end of the holding arc A, with the orientation of the holding member 5 relative to the applicator roll 4 remaining the same or constant. In this example, the contact surface 51 extends at an angle of at least 30 degrees, preferably at least 40 degrees, relative to the vertical plane.

As shown in FIG. 4, the application unit 3 is further provided with a detachment element 52 for detaching the continuous strip 9 from the holding member 5. In this example, the detachment element 52 is a blow-off groove provided in the holding member 5. The blow-off groove can be connected to a source of compressed air. Alternatively, a mechanical detachment element such as a pusher member can be used.

As shown in FIG. 1 , the application unit 3 further includes a drive assembly or mechanism 6 for moving the holding member 5 along the holding arc A. In particular, the drive mechanism 6 includes a first drive unit 61 and a second drive unit 62 for moving the holding member 5 along the holding arc A in a first drive direction D1 with a first vector component V1 and in a second drive direction D2 with a second vector component V2, respectively. The drives 61, 62 may cooperate in this manner to function as an XY drive unit. In other words, the drives 61, 62 are controlled such that the vector components V1, V2 generated by the respective drives 61, 62 in the respective drive directions D1, D2 result in a compound or complex movement of the holding member 5 along a curve that corresponds to the radius and/or curvature of the holding arc A.
In this example, the first drive direction D1 is perpendicular to the roll axis X. In this particular embodiment, the first drive direction D1 is vertical or substantially vertical. Furthermore, in this example, the second drive direction D2 is perpendicular to the first drive direction D1. Thus, in this particular embodiment, the second drive direction D2 extends horizontally or substantially horizontally.

The aforementioned oblique contact angle H of the contact surface 51 can also be measured with respect to the first driving direction D1.

As shown in FIG. 3 , the first drive unit 61 is arranged to move the holding member 5 a first stroke S1 in a first drive direction D1. Similarly, the second drive unit 62 is arranged to move the holding member 5 a second stroke S2 in a second drive direction D2. The first stroke S1 stops or ends at or just before a mid-plane M that passes through the roll axis X and extends perpendicular to the first drive direction D1. In other words, the movement of the holding member 5 is limited to a position away from the mid-plane M, specifically, to a level that intersects with the upper half of the applicator roll 4. In this particular example, the holding member 5 bottoms out at a mid-level somewhere in the upper half of the applicator roll 4 when the first stroke S1 ends.

In this example, the first drive unit 61 is configured to act on the holding member 5 in or parallel to the first drive direction D1. The second drive unit 62 is arranged at an oblique angle to the second drive direction D2. The drive mechanism 6 further includes a carriage 63 that supports or carries the first drive unit 61 and is movable in the second drive direction D2 along a guide 64. The second drive unit 62 is coupled to the carriage 63 and moves the carriage along the guide 64, thereby converting the oblique movement of the second drive unit into linear movement of the carriage 63 in the second drive direction D2.

When the holding member 5 has reached the end or bottomed out of the first stroke S1, the holding member 5 can only move further in the second drive direction D2. The end of the second stroke S2 is selected so that the holding member 5 can be moved in the second drive direction D2 to a position spaced apart, separated or moved away from the holding surface.

In this example, the first drive unit 61 and the second drive unit 62 include or are linear drive units, which are in particular pneumatic cylinders. While the holding member 5 moves along the holding arc A, the pneumatic cylinders are pressurized, and when the holding member 5 is free to move relative to the application roll 4, the holding member 5 is urged to automatically follow the holding arc A in the first drive direction D1 and the second drive direction D2. The pressure is preferably kept constant, for example at 1 bar.

FIG. 7 shows an alternative tire building apparatus 101 according to a second embodiment of the present invention, which differs from the previously described tire building apparatus 1 in that the application unit 103 is provided with a holding member 105, which in particular comprises a pressing conveyor such as a hugger belt 150. The holding member 105 is provided with an infinite contact surface 151, in particular an endless belt, which contacts the continuous strip 9 along a holding arc A. The infinite contact surface 151 may be actively driven at the same or substantially the same speed as the continuous strip 9 to follow it at a holding position P on the application roller 4, or it may passively move together with the application roller 4 as a result of friction between the continuous strip 9 and the infinite contact surface 151. The holding member 105 can be moved toward or away from the application roller 4 in a first drive direction D1 by a first drive 161, in particular a linear drive such as a pneumatic cylinder.

The alternative tire building apparatus 101 further differs from the previously described tire building apparatus 1 in that it further includes a sensor 107 for detecting the leading end LE of the continuous strip 9. Based on the detection of the leading end LE, the holding member 105 can be lowered to the leading end LE of the continuous strip 9 at the appropriate time, i.e., when the leading end LE enters the holding arc A. The sensor 9 can be an optical sensor, a photoelectric sensor, an optical sensor, an image sensor, or a height sensor. Alternatively, a temperature sensor can be used to detect an increase in heat indicating the passage of the hot, freshly extruded leading end LE of the continuous strip 9. The temperature sensor can prevent false detections due to residual elastomer material leaking from the extruder 2.

The sensor 107 may be applied to the tire building apparatus 1 shown in Figures 1 to 6 to control the first drive unit 61 to move the holding member 5 toward the application roll 4.

A method for applying a continuous strip 9 to a drum 8 using the application unit 3 described above will now be briefly described with reference to Figures 1 to 6.

1 shows a situation in which a length of continuous strip 9 is newly extruded and fed to applicator roll 4 until its leading end LE is located at or within holding position P on holding surface 1. In this example, holding position P is initially located above applicator roll 4 and is hereinafter referred to as the zero-degree position about roll axis X. Applicator unit 3 and drum 8 are spaced apart to allow room for holding member 5 to move relative to applicator roll 4. Drive mechanism 6 is operated to move holding member 5 to a start position at the start of each stroke S1, S2. Holding member 5 is located above or directly above leading end LE of continuous strip 9 in first drive direction D1.

2 shows the state in which the first drive 61 is controlled to move the holding member 5 in the first drive direction D1 towards the applicator roll 4 until the holding member 5 comes into contact or abuts the leading end LE of the continuous strip 9 in the first drive direction D1. The holding member 5 presses or holds the leading end LE of the continuous strip 9 against a holding surface at a holding position P, so that the leading end LE can be attracted to the holding surface and securely held in subsequent steps of the method.

3 shows the roller body 40 rotating and holding the continuous strip 9 on the holding surface by suction, i.e., by utilizing the reduced pressure in the first chamber 44, as indicated by the arrow R. At the same time, the drive mechanism 6 is controlled to move the holding member 5 along the holding arc A, following the rotation of the roller body 40, and holding the leading end LE of the continuous strip 9 at a holding position P relative to the holding surface.

In Figure 4, the holding member 5 has reached the end of the first stroke S1 and cannot move further in the first drive direction D1. In other words, the holding member 5 has reached the end of the holding arc A. The separating element 52 is operating to separate the continuous strip 9 from the holding member 5, while the second drive 62 simultaneously begins to move the holding member 5 away from the holding surface in the second drive direction D2.

Figure 5 shows a situation in which the second drive unit 62 has moved the holding member 5 away from and/or away from the applicator roll 4 in the second drive direction D2. The holding member 5 can be returned to the initial position shown in Figure 1.

Figure 6 shows the state in which the first drive unit 61 has reversed and/or retreated to return the holding member 5 to its initial position. The drum 8 moves toward the applicator roll 4 and receives the leading end LE of the continuous strip 9 from the applicator roll 4. The extruder 2 continuously extrudes the continuous strip 9, and the applicator roll 4 continuously coats the continuous strip 9 by wrapping it around the drum 8 several times to form a tire component. During this process, the continuous strip 9 extends only partially around the circumference of the applicator roll 4 before being applied to the drum 8.

It should be understood that the above description is included to illustrate the operation of the preferred embodiment and is not intended to limit the scope of the invention. Many variations within the scope of the invention will be apparent to those skilled in the art from the above description.

1 Tire building apparatus 2 Extruder 3 Application unit 4 Application roll 40 Roller body 41 Holding surface 42 Suction port 43 Inner member 44 First chamber 45 Second chamber 5 Holding member 50 Finger tip 51 Contact surface 52 Pull-off element 6 Drive mechanism 61 First drive 62 Second drive 63 Carriage 64 Guide 8 Drum 9 Continuous strip 101 Alternative tire building apparatus 103 Application unit 105 Holding member 150 Hugger belt 151 Contact surface 161 First drive 107 Sensor A Holding arc C Circumferential direction D1 First drive direction D2 Second drive direction E1 First circumferential cross section E2 Second circumferential cross section H Contact angle LE Leading edge M Middle plane P Holding position R Arrow S1 First stroke S2 Second stroke X Roll axis V1 First vector component V2 Second vector component

Claims (26)

A coating unit for applying a continuous strip to a drum, the coating unit comprising: a coating roll rotatable about a roll axis and having a roller body defining a holding surface extending circumferentially around the roll axis; the coating unit further comprising a holding member for holding the continuous strip in a holding position on the holding surface, the holding member being positioned to follow the continuous strip in the holding position on the holding surface along a holding arc of at least 10 degrees around the roll axis as the roller body rotates about the roll axis. The application unit of claim 1, wherein the holding arc is at least 20 degrees. The application unit according to claim 1, wherein the application unit is equipped with a drive mechanism that moves the holding member along the holding arc. The application unit of claim 3, wherein the drive mechanism is configured to move the holding member away from the holding surface after moving the holding member along the holding arc. The application unit of claim 3, wherein the drive mechanism includes a first drive unit that moves the holding member along the holding arc in a first drive direction with a first vector component, and a second drive unit that moves the holding member in a second drive direction with a second vector component. 6. The application unit of claim 5, wherein the first drive section is arranged to move the holding member through a first stroke in the first drive direction, the first stroke passing through the roll axis and terminating before a mid-plane extending perpendicular to the first drive direction. The application unit according to claim 6, wherein the second drive section is arranged to move the holding member only in the second drive direction away from the holding surface when the holding member reaches the end point of the first stroke. The application unit of claim 5, wherein the first drive direction is perpendicular to the roll axis. The application unit of claim 5, wherein the first drive direction is vertical. The application unit of claim 5, wherein the first drive unit or the second drive unit comprises a linear drive unit. The application unit of claim 1, wherein the holding member includes a finger, a pressure roll, or a pressure conveyor that contacts the continuous strip at the holding position while causing the continuous strip to follow along the holding arc. The application unit of claim 5, wherein the holding member has a contact surface that contacts the continuous strip at the holding position on the holding surface, the contact surface extending at an oblique contact angle with respect to the first drive direction. The application unit of claim 1, further comprising a separating element for separating the continuous strip from the holding member. The application unit of claim 13, wherein the separating element is a blow-off groove provided in the holding member. The coating unit of claim 1, wherein the coating roll further comprises a plurality of suction ports in the roller body for holding the continuous strip against the holding surface by suction. 16. The coating unit of claim 15, wherein the roller body is annular, the coating roll further comprises an inner member concentrically disposed within the roller body, the roller body being rotatable circumferentially around the inner member, the inner member comprising a first chamber in communication with the plurality of suction ports at a first circumferential cross section of the roller body, the first chamber being connectable to a vacuum source that holds the continuous strip against the holding surface at the first circumferential cross section. The application unit of claim 16, wherein the retaining arc at least partially overlaps the first circumferential cross section. The application unit of claim 16, wherein the retaining arc overlaps with the first circumferential cross section by at least 80%. The application unit of claim 16, wherein the inner member has a second chamber in communication with the plurality of suction ports at a second circumferential cross section of the roller body, the second chamber being connectable to a compressed air source for blowing the continuous strip off the holding surface at the second circumferential cross section. The application unit of claim 19, wherein the retention arc reaches an end point before or at the second circumferential cross section. A tire building apparatus that applies a continuous strip to a drum, the tire building apparatus comprising the application unit described in claim 1, and the tire building apparatus further comprising an extruder that continuously extrudes the continuous strip onto the application roll, and the drum that continuously receives the continuous strip from the application roll. 10. A method for applying a continuous strip to a drum using the application unit of claim 1, said method comprising:
rotating the applicator roll about the roll axis while holding the continuous strip on the holding surface by suction;
and holding the continuous strip at the holding position on the holding surface with the holding member while causing the holding member to follow the continuous strip at the holding position on the holding surface along the holding arc as the roller body rotates about the roll axis. The method comprises:
23. The method of claim 22, further comprising the step of moving the retention member away from the retention surface after moving the retention member along the retention arc. The method comprises:
23. The method of claim 22, further comprising the step of separating the continuous strip from the retaining member after moving the retaining member along the retaining arc. The method comprises:
continuously extruding the continuous strip onto the applicator roll;
23. The method of claim 22, further comprising continuously applying the continuous strip onto the drum with the application roll. 23. The method of claim 22, wherein the continuous strip has a leading edge, and the continuous strip is held in the holding position on the holding surface at the leading edge.