WO2021227927A1

WO2021227927A1 - Tire building drum

Info

Publication number: WO2021227927A1
Application number: PCT/CN2021/091938
Authority: WO
Inventors: 吴从高; 曹晓明
Original assignee: 萨驰智能装备股份有限公司
Priority date: 2020-05-15
Filing date: 2021-05-06
Publication date: 2021-11-18
Also published as: CN111469460A

Abstract

A tire building drum, comprising an attachment surface receiving a first tire layer, and two axially spaced support sections. The first tire layer extends axially over the two support sections, each support section is provided with a plurality of rotating bodies which are evenly distributed in a circumferential direction, and the plurality of rotating bodies can be driven to rotate to be positioned in a first or second position; in the first position, the two support sections form a first supporting surface for supporting the first tire layer, with the first supporting surface and the attachment surface being located on the same circumferential surface in the radial direction; and in the second position, the two support sections form an annular concave part, a second supporting surface is formed on the annular concave part, and the second supporting surface is radially lower than the attachment surface.

Description

Tyre building drum

This application claims the priority of the Chinese patent application whose application date is May 15, 2020 and the application number is 202010414298.6. The entire content of this application is incorporated into this application by reference.

Technical field

This application relates to the technical field of tire building equipment, for example, to a tire building drum applied to a tire building machine.

Background technique

The existing semi-steel radial one-step tire building machine includes a belt tread drum and a tire building drum. Among them, the belt tread drum is used to form the tread component, that is, the tire components such as the belt layer, the cap belt, and the tread layer can be sequentially attached to the outer surface of the belt tread drum to form the tread component. The tire building drum is used to build the carcass components, that is, the PA composite layer (made by the splicing of the inner liner and the sidewall layer) and the tire components such as the ply can be sequentially attached to the outer surface of the tire building drum; about two beads It is placed symmetrically on the radial outer side of the ply on the tire building drum; when the inside of the tire component located on the inner side of the bead is inflated, the tire component located on the outer side of the bead is turned up against the tire that fits on the inner side of the bead The outer surface of the part, so the carcass assembly is finished. In addition, tire building drums are also used to compound tread components and carcass components to build tire blanks.

In order to ensure that the vehicle can continue to drive after a puncture or a flat tire, run-flat tires have been gradually applied to some vehicles. In fact, run-flat tires increase the thickness and rigidity of the tire sidewall by adding a layer of rubber reinforcement on the sidewall of the tire. Specifically, during the molding process of the run-flat tire blank, the rubber reinforcement is arranged on the axial inner side of the bead and between the inner liner and the ply. After the tire blank is formed, the rubber reinforcement extends from the bead in the radial direction of the run-flat tire, and is located in the axial direction relative to the sidewall layer and the carcass ply and in the axial direction relative to the inner liner. External location.

For the semi-steel radial one-shot tire building machine, the above-mentioned run-flat tire building technology and special structure put forward the need for improvement of the structure of the tire building drum. US Pat. No. 5,591,288A discloses a tire building drum and a method for building a tire. The tire building drum disclosed in this patent is provided with a drum spacer, and the radial outer surface of the drum spacer is formed with an annular groove for accommodating the rubber reinforcement . Due to the existence of the annular groove, a continuous and flat cylindrical surface cannot be formed on the tire building drum. Therefore, after the inner liner is attached to the outer surface of the tire building drum, the inner liner located radially outside the annular groove cannot be supported, resulting in the end of the inner liner at the groove during the stitching process of the inner liner. Poor quality of end stitching, which in turn affects the quality of tire blanks.

Summary of the invention

The present application provides a tire building drum capable of forming high-quality run-flat tire blanks.

The present application provides a tire building drum for building a run-flat tire blank. The tire building drum includes an attachment surface for receiving a first tire layer, and two axially spaced support sections. The first tire layer extends axially across the two supporting sections, wherein each of the supporting sections is provided with a plurality of rotating bodies that can be rotated evenly distributed in the circumferential direction, and the plurality of rotating bodies can be driven Rotate to be positioned at the first position or the second position. When the plurality of rotating bodies are in the first position, the two supporting sections form a first supporting surface for supporting the first tire layer. A supporting surface and the attaching surface are located on the same circumferential surface in the radial direction. When the plurality of rotating bodies are in the second position, the two supporting sections form an annular recessed portion, and the annular recessed portion is formed A second supporting surface, the second supporting surface being lower than the attaching surface in the radial direction.

The present application also provides a tire building drum, including: a main shaft and two half drums arranged on the main shaft, wherein each half drum includes: a bead locking unit configured to radially support the bead; The turn-up unit is located on the axially outer side of the bead locking unit; the support section is located on the axially inner side of the bead locking unit; the tire building drum has an attachment surface for receiving the first tire layer, the The first tire layer extends axially across two supporting sections; the supporting section is provided with a plurality of rotating bodies uniformly distributed in the circumferential direction, and the rotation axis of the plurality of rotating bodies is parallel to the rotation axis of the tire building drum, Each of the rotating bodies has a first supporting surface area and a second supporting surface area, and the plurality of rotating bodies can be driven to rotate to be positioned at a first position or a second position to selectively cause the plurality of rotating bodies to rotate The first support surface area or the second support surface area of the body is located on the radially outer side of the tire building drum.

Description of the drawings

Fig. 1 is a schematic diagram 1 of a three-dimensional structure of a half drum of a tire building drum provided by this application;

Figure 2 is a second schematic diagram of the three-dimensional structure of the half drum of the tire building drum provided by this application;

3 is a cross-sectional view of the half drum shown in FIG. 1, wherein the first supporting surface area of the rotating body is located on the radially outer side of the tire building drum;

4 is a cross-sectional view of the half drum shown in FIG. 2, wherein the second supporting surface area of the rotating body is located on the radially outer side of the tire building drum to form an annular recess;

Figure 5 is a cross-sectional view of the half drum shown in Figure 4, in which the inner liner and the rubber reinforcement at the annular recess have been placed in the annular recess;

6 is a schematic diagram of a three-dimensional structure of a single rotating body at a first angle;

Fig. 7 is a schematic diagram of a three-dimensional structure of a single rotating body at a second angle;

Figure 8 is a side view 1 of the half drum of the tire building drum of this application, wherein the supporting section is equipped with a rotating body but not equipped with a support;

Figure 9 is the second side view of the half drum of the tire building drum of this application, in which the support section is equipped with supports but not the rotating body;

Figure 10 is a cross-sectional view of the second supporting member and the filling member;

Figure 11 is an enlarged view of H in Figure 1;

Fig. 12 is an enlarged view of K in Fig. 2.

In the picture:

Main shaft 1; Half drum 2; Rotation axis C1;

Bead locking unit 10; support block 11; tapered piston 12;

Turn-up unit 20; turn-up rod 21; support plate 22; turn-up drive assembly 23; rolling element 24; guide plate 25; circumferential surface D; guide body 26;

Support section 30; rotating body 31; axis of rotation C2; first support surface area F1; second support surface area F2; annular recess R; spiral groove G; first support surface S1; second support surface S2; first Support 32; second support 33; filler 34; third support surface area N;

PA composite layer 40; rubber reinforcement 50; ply 60;

Actuating assembly 70; sliding body 71; guide 72;

Gap M; vent X; airway L;

External shaft 80.

Detailed ways

As shown in Figures 1 to 2, the present application provides a tire building drum, which is applied to a semi-steel radial tire one-shot tire building machine for forming run-flat tire blanks. The tire building machine also includes a belt drum (not shown) for forming the tread component, a tread component feeding device (not shown) for conveying the tread component, and a carcass component for conveying the carcass component Equipment or devices such as a feeding device (not shown) and a transfer device or a rolling station located between the belt drum and the tire building drum. The specific structure of the tire building drum will be described in detail below.

As shown in Figs. 1 to 5 and 11 to 12, the tire building drum includes a main shaft 1 and two half drums 2 sleeved outside the main shaft 1. As shown in Figs. Figures 1 to 5 only show the main shaft 1 of the tire building drum and a half drum 2 mounted on the main shaft. Illustratively, the tire building drum has a rotation axis C1, and the two half drums 2 can rotate circumferentially around the rotation axis C1, and can also move toward or away from each other along the main axis. In one embodiment, each half drum 2 includes: a bead locking unit 10 configured to radially support a bead (not shown); a turn-up unit 20 located on the axial outer side of the bead locking unit 10; and a guide The body 26 is ring-shaped, can move axially and cooperates with the turn-up unit 20; and the support section 30 is located on the axial inner side of the bead locking unit 10. The structure of the constituent units of the half drum 2 will be described in detail below.

As shown in FIG. 3, the turn-up unit 20 includes a plurality of turn-up rods 21 evenly distributed in the circumferential direction. It is attached to the tire component located on the axial inner side of the bead. Among them, the tire component includes a PA composite layer 40 (spliced by an inner liner layer and a sidewall layer) and at least one ply layer 60 that are sequentially attached to the outside of the tire building drum. The PA composite layer 40 may be referred to as the first tire layer, and the carcass layer 60 may be referred to as the second tire layer. Wherein, when the turn-up rod 21 is at the initial position, the plurality of turn-up rods 21 are spaced apart from each other and extend along the axial direction of the main shaft 1. The space between the turn-up rods 21 is filled. In this way, the position located on the axially outer side of the bead of the tire building drum and used to support part of the PA composite layer 40 forms a substantially continuous and flat circumferential surface D. The circumferential surface D is formed by the turn-up rod 21 and the guide body 26 together. Surface D serves as a part of the attachment surface of the tire building drum. When the PA composite layer 40 is arranged as the first tire layer on the attachment surface of the tire building drum, the PA composite layer 40 axially extends across two supporting sections 30 arranged axially on the tire building drum.

As shown in Figs. 1 to 5, the supporting section 30 is provided with a plurality of rotating bodies 31 uniformly distributed in the circumferential direction, and the rotation axis C2 corresponding to the plurality of rotating bodies 31 is parallel to the rotation axis C1 of the tire building drum. The structures of the plurality of rotating bodies 31 are the same, and the plurality of rotating bodies 31 can be rotated in the same direction by a certain angle synchronously, and each rotating body 31 can provide at least two different supporting surface areas. In this embodiment, a plurality of rotating bodies 31 can be driven to rotate to be synchronously positioned at the first position or the second position, and each rotating body 31 includes a first supporting surface area F1 and a second supporting surface area F2. Illustratively, when the plurality of rotating bodies 31 are in the first position, the first supporting surface area F1 is located at the radially outer side of the tire building drum, and when the plurality of rotating bodies 31 are in the second position, the second supporting surface area F2 is located at the tire building drum. The radial outside of the drum, where the first supporting surface area F1 is approximately flat, and the second supporting surface area F2 is concave.

As shown in FIGS. 1 and 3, when the plurality of rotating bodies 31 at the supporting section 30 of the tire building drum are in the first position, the plurality of first supporting surface areas F1 of the plurality of rotating bodies 31 at the supporting section 30 are The first supporting surface S1 for supporting the PA composite layer 40 can be formed in the circumferential direction. The first supporting surface S1 and the circumferential surface D are located on the same circumferential surface in the radial direction. Attach the surface. The PA composite layer 40 includes an inner liner in the middle area and a sidewall layer on both sides of the inner liner. The thickness of the sidewall layer is thicker than that of the inner liner. The PA composite layer shown in Figures 3 to 5 is simple Signal. In addition, since the plurality of rotating bodies 31 are arranged at intervals on the circumference, the first supporting surface S1 is discontinuous in the circumferential direction. However, when the PA composite layer 40 is attached to the tire building drum and the end joint stitching process, A supporting surface S1 can also effectively support the head end and the end-to-end butting part of the PA composite layer 40, thereby ensuring the quality of the end-to-end jointing and stitching of the PA composite layer 40, so as to form a high-quality run-flat tire embryo.

The tire building drum of the present application can be used to form a run-flat tire blank. Illustratively, the tire building drum is arranged to receive rubber reinforcement around the PA composite layer 40 at the above-mentioned two axially spaced support sections 30, respectively. Pieces of 50. As shown in Figures 2, 4, 5 and 12, the plurality of rotating bodies 31 at the supporting section 30 of the tire building drum are in the second position, and the plurality of rotating bodies 31 at the supporting section 30 are in the second position. The two supporting surface areas F2 form a second supporting surface S2 for supporting and accommodating the above-mentioned rubber reinforcement 50, wherein the second supporting surface S2 is lower than the above-mentioned attaching surface in the radial direction. The plurality of rotating bodies 31 at the support section 30 can cooperate to form an annular recess R matching the cross-sectional shape of the rubber reinforcement 50. The annular recess R can accommodate the rubber reinforcement 50 to ensure that the radial outer surface of the rubber reinforcement 50 on the tire building drum is substantially flush with the outer surface of the PA composite layer 40 located outside the annular recess R, so that the ply 60 The bonding surface is basically flat, ensuring that the plies 60 are spliced accurately at the head and tail ends. In addition, the PA composite layer 40 attached to the tire building drum is only partially stretched inside the support section 30 and is recessed in the annular recess R. The rubber reinforcement 50 is attached to the radial direction of the PA composite layer 40. The outside is completely contained in the recess R. In this way, while satisfying that the rubber reinforcement 50 can be accommodated in the recess R, it also reduces the risk of wrinkles or other irregular stretching deformations formed in the rest of the PA composite layer 40 attached to the tire building drum. In this way, it is ensured that the tire building drum can form high-quality run-flat tire blanks.

As shown in FIGS. 3 to 7, the half drum 2 also includes an actuating assembly 70 for driving a plurality of rotating bodies 31 to rotate synchronously in the same direction. The actuating assembly 70 can synchronize the positioning of a plurality of rotating bodies 31 at the first position and the second position. In an embodiment, the actuating assembly 70 includes a sliding body 71 that can move axially and a plurality of guide members 72 that are arranged on the sliding body 71 and are evenly distributed along the circumferential direction. The plurality of guide members 72 are matched with the plurality of rotating bodies 31 in a one-to-one correspondence, the plurality of guide members 72 are at least partially located on the radially outer side of the sliding body 71, and the plurality of guide members 72 are fixedly connected to the sliding body 71 or more The guide 72 is inserted on the sliding body 71. Correspondingly, as shown in FIG. 7, the rotating body 31 is provided with a spiral groove G, and one end of the guide member 72 is located in the spiral groove G. In this way, when the sliding body 71 moves in the axial direction of the main shaft 1, the plurality of guides 72 follow the sliding body 71 to move in the axial direction. Since one end of the plurality of guide members 72 is located in the spiral groove G, while the plurality of guide members 72 move axially, one end of the plurality of guide members 72 also slides in the spiral groove G of the plurality of rotating bodies 31, and then The plurality of rotating bodies 31 are driven to rotate synchronously in the same direction to switch the supporting surface.

In this way, by driving the plurality of rotating bodies 31 at the support section 30 to rotate, the first support surface S1 or the second support surface S2 can be selectively provided at the support section 30 to meet the requirements of the molding process at each stage of the tire building process. need.

In addition, the axial movement of the sliding body 71 along the main shaft 1 can be achieved by pneumatic, hydraulic or electric driving methods, which are common knowledge in the art and will not be repeated here.

In an embodiment, as shown in FIGS. 3 to 5, the supporting section 30 further includes an annular supporting body, and a plurality of rotating bodies 31 are evenly distributed and rotatably supported on the supporting body. In this embodiment, the sliding body 71 is similar to a piston body and has a ring shape. The sliding body 71 is housed in the support body and can move axially in the support body. In this embodiment, the support body includes a first support 32 and a second support 33 that cooperates with the first support 32. The first support 32 and the second support 33 cooperate with each other in the radial direction. The supporting member 32 and the second supporting member 33 jointly form a supporting body. The plurality of rotating bodies 31 are located on the radially outer side of the sliding body 71.

With reference to Figs. 3 to 4, it will be described in detail how the actuating assembly 70 drives the rotating body 31 to locate different supporting surface areas on the radially outer side of the tire building drum.

As shown in FIG. 3, when the sliding body 71 moves toward the side close to the bead locking unit 10 along the axial direction of the main shaft 1, the plurality of rotating bodies 31 synchronously rotate a certain angle in the first direction (not shown) around the respective rotation axis C2. When the sliding body 71 moves to the set axial position, the plurality of rotating bodies 31 are positioned at the first position, so that the first supporting surface area F1 of the plurality of rotating bodies 31 is located on the radially outer side of the tire building drum, thereby supporting The above-mentioned first supporting surface S1 can be formed at the section 30.

As shown in FIG. 4, when the sliding body 71 moves away from the bead locking unit 10 in the axial direction of the main shaft 1, the plurality of rotating bodies 31 move in a second direction (not shown) opposite to the above-mentioned first direction around the respective rotation axis C2. ) Synchronously rotate at a certain angle. After the sliding body 71 moves to the set axial position, the plurality of rotating bodies 31 are positioned at the second position, so that the second supporting surface area F2 of the plurality of rotating bodies is located on the radially outer side of the tire building drum, thereby supporting the section 30 can form the aforementioned second supporting surface S2, and an annular recess R matching the cross-sectional shape of the rubber reinforcement 50 is formed on the second supporting surface S2.

As shown in FIG. 8, in order to avoid interference of the multiple rotating bodies 31 during synchronous rotation, the multiple rotating bodies 31 are arranged at intervals, that is, when the multiple rotating bodies 31 are in the first position or the second position, they are adjacent to each other. There is a gap M between the rotating bodies 31.

In one embodiment, as shown in FIGS. 2 to 5 and 9 to 12, the support body further includes a plurality of fillers 34 extending in the axial direction and arranged at even intervals in the circumferential direction. Optionally, the filler 34 has a third supporting surface area N, and the configuration of the third supporting surface area N is consistent with the configuration of the second supporting surface area F2. When the plurality of rotating bodies 31 are positioned at the second position, the second supporting surface S2 that is substantially continuous and closed in the circumferential direction on the supporting section 30 is formed. In fact, the second supporting surface S2 is jointly formed by the second supporting surface area F2 of the plurality of rotating bodies 31 and the third supporting surface area N of the filler 34. In this way, the rubber reinforcement 50 can be more completely contained in the annular recess R and can be well supported.

Since the supporting section 30 forms a substantially continuous and closed second supporting surface S2 in the circumferential direction, when the PA composite layer 40 is recessed into the annular recess R by external force (direct pressing or negative pressure adsorption, etc.), the original Indentation is generated on the PA composite layer 40 due to the existence of the gap M, or to avoid the occurrence of air bubbles between the PA composite layer 40 and the rubber reinforcement 50 due to the force of the PA composite layer 40 and being trapped in the gap. There is a risk that the PA composite layer 40 at the annular recess R will be stretched again during inflation and expansion, thereby effectively improving the quality of the tire carcass component molding and increasing the product qualification rate.

As shown in FIGS. 6 to 7, in an embodiment, the rotating body 31 is provided with an axially extending air passage L, and a plurality of vent holes communicating with the air passage L and extending radially to the second supporting surface area F2 X. In this way, a part of the PA composite layer 40 can fit in the annular recess R under the action of negative pressure.

In addition, the specific structure of other components in the tire building drum and the cooperation relationship between each other will be described in detail with reference to FIGS. 1 to 5.

The half drum 2 further includes an outer shaft 80 which is sleeved outside the main shaft 1 and coaxially arranged with the main shaft 1.

Optionally, the turn-up unit 20 further includes a support disk 22, a turn-up drive assembly 23 and a guide disk 25. The first end of the turn-up rod 21 is pivotally connected to the support plate 22, and the second end of the turn-up rod 21 is rotatably connected with the rolling element 24 and is located outside the guide plate 25. The turn-up drive assembly 23 is configured to drive the support disk 22 to move axially along the outer shaft 80 to drive the turn-up rod 21 and the rolling element 24 to move. The guide plate 25 is sleeved on the outer shaft 80 and fixedly connected with the outer shaft 80. The rolling element 24 can be roll-fitted with the outer circumferential arc surface of the guide plate 25.

In one embodiment, the bead locking unit 10 includes: a plurality of support blocks 11 arranged in a circumferential array, which are arranged between the guide plate 25 and the first support 32; The radially inner side of the support block 11 forms a taper fit. The axial movement of the tapered piston 12 can drive the support block 11 to move radially.

Next, the working process of the tire building drum of the present application will be described in detail with reference to FIGS. 3 to 5 and the molding process of the run-flat tire blank in the one-shot tire building machine.

In the first stage, the PA composite layer 40 is attached to the tire building drum. As shown in FIG. 3, the turn-up rod 21 is at the initial position, and a plurality of turn-up rods 21 extend along the axial direction of the main shaft 1. The plurality of turn-up rods 21 cooperate with the guide body 26 to form a substantially continuous and flat circumferential surface D for supporting the partial PA composite layer 40 on the axially outer side of the bead locking unit 10. At the same time, the plurality of rotating bodies 31 at the support section 30 are positioned at the first position under the drive of the actuating assembly 70, so that the first supporting surface area F1 of the plurality of rotating bodies 31 is located radially outside of the tire building drum, To form the first supporting surface S1 in the circumferential direction, the first supporting surface S1 and the circumferential surface D together form an attachment surface for attaching the PA composite layer 40 to receive the PA composite layer 40.

In the second stage, two rubber reinforcements 50 need to be attached to a designated position on the radially outer side of the PA composite layer 40. Wherein, the above-mentioned designated position refers to a position that is radially aligned with the annular recess R. In this embodiment, after the two rubber reinforcements 50 are attached to the designated positions on the radially outer side of the PA composite layer 40, the plurality of rotating bodies 31 are switched from the above-mentioned first position to the second position, so that the PA composite layer 40 is When a part of the rubber reinforcement 50 is contained in the annular recess R, it is ensured that the radial outer surface of the rubber reinforcement 50 is substantially flush with the outer surface of the PA composite layer 40 located outside the designated position. Therefore, the ply 60 is smoothly attached to the outer surfaces of the PA composite layer 40 and the rubber reinforcement 50, ensuring that the end-to-end splicing of the ply 60 is accurate. In this way, the tire building drum provided in the present application can be used in a one-shot tire building machine to build high-quality carcass components, and then a high-quality run-flat tire blank can be molded. As shown in FIGS. 4 to 5, the turn-up rod 21 is still in the initial position, and the plurality of rotating bodies 31 at the support section 30 reach the second position under the drive of the actuating assembly 70, so that the plurality of rotating bodies 31 The second support surface area F2 is located on the radially outer side of the tire building drum, so that the plurality of rotating bodies 31 and the filler 34 at the support section 30 can cooperate to form an annular recess that matches the cross-sectional shape of the rubber reinforcement 50 R, and the annular recess R has a substantially continuous second supporting surface S2. By applying an external force (for example, negative pressure adsorption) to the PA composite 40 and the rubber reinforcement 50 at the designated position, the PA composite 40 and the rubber reinforcement 50 at the annular recess R are accommodated in the annular recess R.

For the second stage, there is an alternative implementation (not shown). That is, before the two rubber reinforcements 50 are attached to the designated position on the radially outer side of the PA composite layer 40, the plurality of rotating bodies 31 are switched from the above-mentioned first position to the second position, and then an external force (such as suction by a negative pressure) is applied. ) The PA composite layer 40 at the designated position is indented and accommodated in the annular recess R, and then the rubber reinforcement 50 is attached to the radial outside of the PA composite layer 40 in the annular recess R, and the rubber reinforcement is secured The radial outer surface of 50 is substantially flush with the outer surface of the PA composite layer 40 located outside the designated position.

Compared with related technologies, the tire building drum provided by this application:

There are multiple rotating bodies 31 on the tire building drum support section. By driving the multiple rotating bodies 31 to rotate, they can be selectively and synchronously positioned at the first position or the second position, and different first support surface areas F1 or second The support surface area F2 is placed on the radially outer surface of the tire building drum to provide a first support surface S1 or a second support surface S2 at the support section 30 to meet the needs of the molding process at each stage of the tire building process, and can Molding high-quality run-flat tire blanks. Among them, the first supporting surface S1 can also effectively support the butt joints of the inner liner layer 40 on the PA composite layer 40, so as to ensure the quality of the butt joint and stitching of the PA composite layer 40. The second supporting surface S2 is formed with an annular recess R containing the rubber reinforcement 50, so as to satisfy the molding process of a run-flat tire.

Claims

A tire building drum is used to build a run-flat tire blank. The tire building drum includes an attachment surface for receiving a first tire layer, and two axially spaced support sections. The first tire layer Axially extends across two of the supporting sections, wherein each of the supporting sections is provided with a plurality of rotatable rotating bodies uniformly distributed in the circumferential direction, and the plurality of rotating bodies can be driven to rotate to be positioned at In the first position or the second position, when the plurality of rotating bodies are in the first position, the two supporting sections form a first supporting surface for supporting the first tire layer, and the first supporting surface is connected to The attachment surface is located on the same circumferential surface in the radial direction, and when the plurality of rotating bodies are in the second position, the two supporting sections form an annular recessed portion, and a second supporting surface is formed on the annular recessed portion , The second supporting surface is lower than the attaching surface in the radial direction.
The tire building drum according to claim 1, wherein: each of the rotating bodies has a first supporting surface area and a second supporting surface area, and when the plurality of rotating bodies are in the first position, a plurality of the The first supporting surface area forms the first supporting surface, and when the plurality of rotating bodies are in the second position, the plurality of second supporting surface areas form the second supporting surface.
The tire building drum according to claim 1, wherein: each of the rotating bodies has a first supporting surface area and a second supporting surface area, and when the plurality of rotating bodies are in the first position, a plurality of the The first supporting surface area forms the first supporting surface, and the supporting section is further provided with a plurality of fillers extending in the axial direction and evenly spaced in the circumferential direction, each of the fillers having a third supporting surface area When the plurality of rotating bodies are in the second position, a plurality of the second supporting surface area and a plurality of the third supporting surface area cooperate to form the second supporting surface, the second supporting surface Basically continuous in the circumferential direction.
The tire building drum according to any one of claims 1 to 3, wherein: the plurality of rotating bodies are arranged at intervals in the circumferential direction, and the first supporting surface is discontinuous in the circumferential direction.
The tire building drum according to any one of claims 1 to 3, wherein: the tire building drum is arranged for receiving around the first tire layer at the two axially spaced support sections, respectively Rubber reinforcement.
The tire building drum according to claim 5, wherein the plurality of rotating bodies are driven to rotate before receiving a rubber reinforcement around the first tire layer at the two axially spaced support sections. The first position is switched to the second position.
The tire building drum according to claim 5, wherein after receiving a rubber reinforcement around the first tire layer at the two axially spaced support sections, the plurality of rotating bodies are driven to rotate by all The first position is switched to the second position.
A tire building drum includes: a main shaft and two half drums arranged on the main shaft, wherein each half drum includes:

The bead locking unit is configured to radially support the bead;

The turn-up unit is located on the axially outer side of the bead locking unit;

A supporting section located on the axial inner side of the bead locking unit;

The tire building drum has an attachment surface for receiving a first tire layer, the first tire layer axially extending across two supporting sections; the supporting section is provided with a plurality of rotating bodies uniformly distributed in the circumferential direction, The rotation axis of the plurality of rotating bodies is parallel to the rotation axis of the tire building drum, each of the rotating bodies has a first supporting surface area and a second supporting surface area, and the plurality of rotating bodies can be driven to rotate to be positioned at A first position or a second position to selectively make the first support surface area or the second support surface area of the plurality of rotating bodies located on the radially outer side of the tire building drum.
The tire building drum according to claim 8, wherein: when the plurality of rotating bodies are in the first position, the plurality of first support surface areas on the support section form a first support surface, so The first supporting surface and the attaching surface are located on the same circumferential surface in the radial direction; when the plurality of rotating bodies are in the second position, the plurality of second supporting surface areas on the supporting section form The second supporting surface is radially concave relative to the attaching surface.
The tire building drum according to claim 8, wherein: when the plurality of rotating bodies are in the first position, the plurality of first support surface areas on the support section form a first support surface, so The first supporting surface and the attaching surface are located on the same circumferential surface in the radial direction; the supporting section is also provided with a plurality of fillers extending in the axial direction and arranged in the circumferential direction, and each of the fillers has The third supporting surface area; when the plurality of rotating bodies are positioned at the second position, the second supporting surface area of the plurality of rotating bodies and the third supporting surface area of the filler together form the second A supporting surface, the second supporting surface being radially concave with respect to the attaching surface.
9. The tire building drum according to claim 10, wherein: the plurality of rotating bodies and the plurality of fillers are spaced apart from each other in the circumferential direction, and the second supporting surface is substantially continuous.
The tire building drum according to claim 10 or 11, wherein: the half drum further includes an actuation assembly for driving the plurality of rotating bodies to rotate in the same direction synchronously, so that the plurality of rotating bodies can be synchronized Positioned at the first position or the second position.
The tire building drum according to claim 12, wherein: the support section is further provided with an annular support body, and the plurality of rotating bodies are evenly distributed and rotatably supported on the support body.
The tire building drum according to claim 13, wherein: the actuating assembly is housed in the supporting body and can move axially in the supporting body, and the plurality of rotating bodies are located in the radial direction of the actuating assembly Outside.
The tire building drum according to claim 12, wherein: the actuating assembly includes an axially movable sliding body and a plurality of guides arranged on the sliding body and uniformly distributed in the circumferential direction; Each guide member corresponds to the plurality of rotating bodies one-to-one, the rotating body is provided with a spiral groove, and one end of each guide member is located in the spiral groove.
The tire building drum according to any one of claims 8 to 10, wherein the plurality of rotating bodies are arranged at intervals in the circumferential direction, and the first supporting surface is discontinuous in the circumferential direction.
The tire building drum according to claim 13, wherein the support body includes a first support member and a second support member that cooperates with the first support member in a radial direction.
The tire building drum according to claim 17, wherein the plurality of fillers are integrally provided with the second support member or the plurality of fillers are fixedly connected to the second support member.
The tire building drum according to any one of claims 8 to 10, wherein: the rotating body is provided with an air passage communicating with an external air source, and a plurality of air channels are formed on the second supporting surface area. Connected vent holes.