CN111469460A

CN111469460A - Tire building drum

Info

Publication number: CN111469460A
Application number: CN202010414298.6A
Authority: CN
Inventors: 吴从高; 曹晓明
Original assignee: Suzhou Sachi Huachen Machinery Co Ltd
Current assignee: Suzhou Sachi Huachen Machinery Co Ltd
Priority date: 2020-05-15
Filing date: 2020-05-15
Publication date: 2020-07-31
Also published as: WO2021227927A1

Abstract

The invention provides a tyre building drum having an application surface for receiving a first tyre layer, and having two axially spaced support sections, the first tyre layer extending axially over the two support sections, each support section being provided with a plurality of rotators which are equispaced circumferentially and which are drivable in rotation to be positioned in a first or second position, in the first position the support sections forming a first support surface for supporting the first tyre layer, the first support surface being located radially on the same circumference as the application surface, in the second position the support sections forming an annular recess on which a second support surface is formed, the second support surface being radially lower than the application surface. Thus, the tire building drum provided by the invention can selectively provide the first or second supporting surface at the supporting section by driving the plurality of rotating bodies to rotate, so as to meet the requirement of a high-quality run-flat tire building process at each stage.

Description

Tire building drum

Technical Field

The invention relates to the technical field of tire forming equipment, in particular to a tire forming drum applied to a tire forming machine.

Background

The existing semi-steel meridian method one-step tire building machine comprises a belt tread drum and a tire building drum. Wherein the belt and tread drum is used for building a tread assembly, i.e. tire components such as belt, cap and tread layers may be sequentially applied to the outer surface of the belt and tread drum to form the tread assembly. The tire building drum is used for building a tire body assembly, namely, tire components such as a PA composite layer (formed by splicing an inner liner layer and a side wall layer) and a cord fabric layer and the like can be sequentially attached to the outer surface of the tire building drum; the two tire beads are arranged on the radial outer side of the cord fabric layer on the tire building drum in a bilateral symmetry mode; when the inner part of the tire component positioned at the inner side of the tire bead is inflated, the tire component positioned at the outer side of the tire bead is turned up to be abutted against the outer surface of the tire component attached to the inner side of the tire bead, so that the tire body assembly is formed. In addition, tire building drums are used to combine tread and carcass components to form a tire blank.

Run-flat tires have been gradually applied to some vehicles in order to ensure that the vehicles continue to run after a tire burst or air loss. In fact, run-flat tires increase tire sidewall thickness and stiffness by adding a layer of rubber reinforcement to the sidewall portion of the tire. Specifically, during the molding of the run-flat tire blank, the rubber reinforcement is disposed axially inward 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, at a position axially inward with respect to both the sidewall layer and the carcass ply and axially outward with respect to the inner liner.

The above-described run-flat tire building process and special structure put improved demands on the structure of the tire building drum for a semi-steel radial one-off tire building machine. US patent US5591288A discloses a tyre building drum and a method of building a tyre, in particular a tyre building drum in which drum spacers are provided, and the radially outer surfaces of which drum spacers are formed with annular grooves for receiving rubber reinforcements. Due to the presence of the annular groove, a continuous 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 forming drum, the inner liner located on the radial outer side of the annular groove cannot be supported, the sewing quality of the head end and the tail end of the inner liner located in the groove in the sewing process of the inner liner is poor, and the quality of a tire blank is influenced.

In view of the above, there is a need for an improved tire building drum that solves the above problems.

Disclosure of Invention

The invention aims to provide a tire building drum which is used for building a high-quality run-flat tire blank.

To achieve the above object, the present invention provides a tyre building drum for building a run-flat tyre blank, the tyre building drum having an application surface for receiving a first tyre layer, the tyre building drum having two axially spaced support segments, the first tyre layer extending axially beyond the two support segments, each support segment being provided with a plurality of rotatable rotation bodies evenly distributed in a circumferential direction, the plurality of rotation bodies being drivable in rotation to be positioned in a first position in which the support segments form a first support surface for supporting the first tyre layer, the first support surface being radially on the same circumference as the application surface, or in a second position in which the support segments form an annular recess on which a second support surface is formed, the second support surface is radially lower than the attachment surface.

Further, each of the rotating bodies has a first supporting surface and a second supporting surface, the plurality of first supporting surfaces form the first supporting surface when the plurality of rotating bodies are in the first position, and the plurality of second supporting surfaces form the second supporting surface when the plurality of rotating bodies are in the second position.

Further, each rotating body is provided with a first supporting surface and a second supporting surface, when the rotating bodies are in the first position, the first supporting surfaces form the first supporting surface, the supporting section is further provided with a plurality of filling pieces which extend axially and are uniformly arranged at intervals in the circumferential direction, and each filling piece is provided with a third supporting surface; when the plurality of rotating bodies are in the second position, the second supporting surface and the third supporting surface cooperate to form the second supporting surface, and the second supporting surface is substantially continuous in the circumferential direction.

Further, the plurality of rotating bodies are arranged at intervals in the circumferential direction, and the first support surface is discontinuous in the circumferential direction.

Further, the tyre building drum is arranged for receiving a rubber reinforcement around the first tyre layer at the two axially spaced support sections, respectively.

Further, the plurality of rotary bodies are driven in rotation to switch from the first position to the second position before receiving rubber reinforcement around the first tyre layer at the two axially spaced support sections.

Further, the plurality of rotary bodies are driven in rotation to switch from the first position to the second position after receiving rubber reinforcement around the first tyre layer at the two axially spaced support sections.

For the purpose of the present invention, the invention also provides a tyre building drum comprising: the main shaft and set up in two on the main shaft are half the drum, every half drum all includes: a bead locking unit for radially supporting the bead; a turn-up unit located axially outside the bead lock unit; each half-drum further comprises a support section located axially inside the bead locking unit; the tyre building drum having an application surface receiving a first tyre layer extending axially over both of the support segments; the support section is provided with a plurality of rotating bodies which are uniformly distributed in the circumferential direction, the rotation axes of the plurality of rotating bodies are parallel to the rotation axis of the tire building drum, each rotating body has a first support surface and a second support surface, and the plurality of rotating bodies can be driven to rotate to be positioned at a first position or a second position so as to selectively enable the first support surface or the second support surface of the plurality of rotating bodies to be positioned at the radial outer side of the tire building drum.

Further, when the plurality of rotating bodies are at the first position, the plurality of first supporting surfaces on the supporting section form a first supporting surface, and 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 surfaces on the supporting section form the second supporting surface, and the second supporting surface is concave in the radial direction relative to the attaching surface.

Further, when the plurality of rotating bodies are at the first position, the plurality of first supporting surfaces on the supporting section form a first supporting surface, and 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 filling pieces which extend axially and are arranged in the circumferential direction, and each filling piece is provided with a third supporting surface; when the plurality of rotating bodies are positioned at the second position, the second supporting surfaces of the plurality of rotating bodies and the third supporting surface of the filling piece together form the second supporting surface, and the second supporting surface is concave in the radial direction relative to the attaching surface.

Further, the plurality of rotating bodies and the plurality of filling members are arranged at intervals from each other in the circumferential direction, and the second supporting surface is substantially continuous.

Further, the half drum also comprises an actuating assembly for driving the plurality of rotating bodies to synchronously rotate along the same direction, so that the plurality of rotating bodies can be synchronously positioned at the first position or the second position.

Furthermore, the supporting section is also provided with an annular supporting body, and the plurality of rotating bodies are uniformly distributed and rotatably supported on the supporting body.

Further, the actuating assembly is accommodated in the support body and can move axially in the support body, and the plurality of rotating bodies are located on the radial outer side of the actuating assembly.

Further, the actuating assembly comprises a sliding body capable of moving axially and a plurality of guide pieces which are arranged on the sliding body and are uniformly distributed along the circumferential direction; the guide pieces correspond to the rotating bodies one to one, spiral grooves are formed in the rotating bodies, and one end of each guide piece is located in each spiral groove.

Further, the support body comprises a first support and a second support matched with the first support in the radial direction.

Further, the plurality of fillers are provided integrally with the second support member or the plurality of fillers are fixedly connected to the second support member.

Furthermore, an air passage communicated with an external air source is formed in the rotating body, and a plurality of vent holes communicated with the air passage are formed in the second supporting surface.

Compared with the prior art, the tire forming drum provided by the invention has the following beneficial technical effects:

the tire building drum supporting section is provided with a plurality of rotating bodies which are driven to rotate to be selectively and synchronously positioned at a first position or a second position, different first supporting surfaces or different second supporting surfaces are arranged on the radial outer surface of the tire building drum, so that a first supporting surface or a second supporting surface is provided at the supporting section, the requirements of the forming process at each stage in the tire forming process are met, and a high-quality run-flat tire blank can be formed. Wherein, the first supporting surface can also effectively support the head end of the inner liner layer on the PA composite layer and the butt joint part of the head and the tail, thereby ensuring the butt joint and the sewing quality of the PA composite layer 40. An annular recess for receiving the rubber reinforcement is formed on the second support surface, thereby satisfying the molding process of the run-flat tire.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a first perspective view of a half drum of a tire building drum according to the present invention;

FIG. 2 is a schematic perspective view of a second drum half of the tire building drum provided in the present invention;

FIG. 3 is a cross-sectional view of the half drum shown in FIG. 1 with the first support surface of the rotary body located radially outward of the tire building drum;

FIG. 4 is a cross-sectional view of the half drum shown in FIG. 2 with the second support surface of the rotary body located radially outward of the tire building drum to form an annular recess;

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

FIG. 6 is a schematic perspective view of a first angle of a single rotating body;

FIG. 7 is a perspective view of a second angle of a single rotating body;

FIG. 8 is a side view one of the half-drums of the tire building drum of the present invention with the support sections fitted with the rotating bodies but without the supports;

FIG. 9 is a second side view of the half-drum of the tire building drum of the present invention with the support segments assembled with the support members but unassembled with the rotating bodies;

FIG. 10 is a cross-sectional view of the second support member and the filler member;

FIG. 11 is an enlarged view taken at H in FIG. 1;

fig. 12 is an enlarged view at K in fig. 2.

In the figure:

a main shaft 1; a half drum 2; the rotation axis C1;

a bead lock unit 10; a stay block 11; a conical piston 12;

an anti-wrap unit 20; a turn-up bar 21; a support disc 22; a turn-up drive assembly 23; a rolling element 24; a guide disc 25; a circumferential surface D; a guide body 26;

a support section 30; the rotating body 31; the axis of rotation C2; a first supporting surface F1; the second supporting surface F2; an annular recess R; a helical groove G; the first support surface S1; the second support surface S2; a first support 32; a second support member 33; a filler 34; a third support surface N;

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

an actuating assembly 70; a slider 71; a guide 72;

gap M, vent X, air passage L;

an outer shaft 80.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the specific embodiments of the present invention and the accompanying drawings. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1 to 2, the present invention provides a tire building drum applied to a one-step tire building machine for a semi-steel radial tire for building a run-flat tire blank. The tire building machine further includes a belt drum (not shown) for building a tread assembly, a tread member serviser (not shown) for delivering tread members, a carcass assembly serviser (not shown) for delivering carcass members, and a transfer device or stitching station between the belt drum and the tire building drum. The following is a detailed description of the specific structure of the tire building drum.

As shown in fig. 1 to 5, 11 to 12, the tire building drum includes: the main shaft 1 and two half drums 2 sleeved outside the main shaft 1. Fig. 1 to 5 show only the spindle 1 of the tire building drum and one half drum 2 mounted on the spindle. In particular, the tyre building drum has a rotation axis C1, the two half-drums 2 being circumferentially rotatable about the rotation axis C1 and also being movable towards and away from each other along the main shaft. Further, each half drum 2 comprises: a bead lock unit 10 for radially supporting a bead (not shown); a turn-up unit 20 located axially outside the bead lock unit 10; a guide body 26, which is annular, axially movable and cooperates with the turn-up unit 20; and a support section 30 located axially inside the bead lock unit 10. The following is a detailed description of the structure of each constituent unit of the half drum 2.

As shown in fig. 3, the turn-up unit 20 includes a plurality of turn-up rods 21 uniformly distributed along the circumferential direction for turning up the tire component located at the axially outer side of the bead (not shown) against and fitting on the tire component located at the axially inner side of the bead, wherein the tire component includes a PA composite layer 40 (formed by splicing an inner liner and a sidewall layer) and at least one ply 60 which are fitted outside the tire building drum in sequence. When the turn-up rods 21 are at the initial position, the turn-up rods 21 extend in the axial direction of the main shaft 1 at intervals, and the guide body 26 is annular and is mounted at the front ends of the turn-up rods 21 to fill the intervals between the turn-up rods 21. In this way, the position axially outside the bead of the tyre building drum and intended to support part of the PA composite layer 40 forms a substantially continuous and flat circumferential surface D, jointly formed by the turnup rod 21 and the guide body 26, which is part of the laying surface of the tyre building drum. When the PA composite layer 40 is arranged as a first tyre layer on the application surface of the tyre building drum, the PA composite layer 40 extends axially over two axially spaced support sections on the tyre building drum.

As shown in fig. 1 to 5, a plurality of rotating bodies 31 are provided at the supporting section 30, which are evenly distributed in the circumferential direction, and the rotational axes C2 of the plurality of rotating bodies 31 are parallel to the rotational axis C1 of the tire building drum. The plurality of rotating bodies 31 are all the same in structure, the plurality of rotating bodies 31 can synchronously rotate for a certain angle along the same direction, and each rotating body 31 can provide at least two different supporting surfaces. In the present embodiment, the plurality of rotating bodies 31 may be driven to rotate to be positioned at the first position or the second position synchronously, each rotating body 31 includes a first supporting surface F1 and a second supporting surface F2, specifically, when the plurality of rotating bodies 31 are at the first position, the first supporting surface F1 is located at the radial outer side of the tire building drum, and when the plurality of rotating bodies 31 are at the second position, the second supporting surface F2 is located at the radial outer side of the tire building drum, wherein the first supporting surface F1 is approximately planar, and the second supporting surface F2 is concave.

As shown in fig. 1 and 3, when the plurality of rotating bodies 31 at the supporting section 30 of the tire building drum are at the first position, the plurality of first supporting surfaces F1 of the plurality of rotating bodies 31 at the supporting section 30 can form a first supporting surface S1 for supporting the PA composite layer 40 in the circumferential direction, and the first supporting surface S1 and the circumferential surface D are located on the same circumferential surface in the radial direction, and both of them collectively serve as an attaching surface for attaching the PA composite layer 40. The PA composite layer 40 includes an inner liner layer located in a middle region and sidewall layers located at both sides of the inner liner layer, and the thickness of the sidewall layers is thicker than that of the inner liner layer, and it should be noted that the PA composite layers shown in fig. 3 to 5 are simple schematic diagrams. Further, since the plurality of rotating bodies 31 are provided at intervals in the circumferential direction, the first support surface S1 is discontinuous in the circumferential direction, but the first support surface S1 can effectively support the leading end and the trailing end of the PA composite layer 40 even in the process of bonding the PA composite layer 40 to the tire building drum and seaming the trailing end joint, thereby ensuring the quality of the trailing end joint and seaming of the PA composite layer 40 and enabling the molding of a high-quality run-flat tire blank.

The tyre building drum of the present invention may be used for building run-flat tyre blanks, in particular arranged for receiving rubber reinforcements 50 around the PA composite layer 40 at the two axially spaced support sections 30, respectively. As shown in fig. 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 second supporting surfaces F2 of the plurality of rotating bodies 31 at the supporting section 30 form a second supporting surface S2 for supporting and accommodating the rubber reinforcement, wherein the second supporting surface S2 is lower than the attaching surface in the radial direction. The plurality of rotating bodies 31 at the supporting section 30 can be fitted to form an annular recess R matching the cross-sectional shape of the rubber reinforcement 50. The annular recess R may receive the rubber reinforcement 50 to ensure that the radially 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 conforming surface of the ply 60 is substantially flat to ensure that the plies 60 are spliced end to end accurately. In addition, the PA composite layer 40 attached to the tire building drum is recessed and partially stretched only at the support section 30 and is recessed and accommodated in the annular recess R, and the rubber reinforcement 50 is attached to the radial outer side of the PA composite layer 40 and is completely accommodated in the recess R. In this way, while the rubber reinforcement 50 can be accommodated in the recessed portion R, the risk of the remaining portion of the PA composite layer 40 attached to the tire building drum forming wrinkles or other irregular tensile deformations is also reduced. Thus, the tire forming drum can form a high-quality run-flat tire blank.

As shown in fig. 3 to 7, the half drum 2 further includes an actuating assembly 70 for driving the plurality of rotating bodies 31 to rotate synchronously in the same direction. The actuating assembly 70 can simultaneously position the plurality of rotating bodies 31 at the first position and the second position. Specifically, the actuating assembly 70 includes an axially movable slide body 71 and a plurality of guides 72 disposed on the slide body 71 and evenly distributed in a circumferential direction. Further, a plurality of guides 72 are engaged with a plurality of rotating bodies 31 in a one-to-one correspondence, the plurality of guides 72 are at least partially located at a radial outer side of the sliding body 71, and the plurality of guides 72 are fixedly connected with the sliding body 71 or the plurality of guides 72 are inserted on the sliding body 71. Accordingly, as shown in fig. 7, the rotating body 31 is formed with a spiral groove G, and one end of the guide 72 is located in the spiral groove G. As such, when the slider 71 moves in the axial direction of the spindle 1, the plurality of guides 72 follow the axial movement of the slider 71. Since one end of the plurality of guides 72 is located in the spiral groove G, while the plurality of guides 72 axially move, one end of the plurality of guides also slides in the spiral groove G of the plurality of rotating bodies 31, thereby driving the plurality of rotating bodies 31 to synchronously rotate in the same direction to switch the supporting surface.

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

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

Further, as shown in fig. 3 to 5, the supporting section 30 further includes an annular supporting body, and the plurality of rotating bodies 31 are uniformly distributed and rotatably supported on the supporting body. In the present embodiment, the sliding body 71 is similar to a piston body and has a ring shape, and the sliding body 71 is accommodated in the support body and can move axially in the support body. In the present embodiment, the supporting body includes a first supporting member 32 and a second supporting member 33 matched with the first supporting member 32, the first supporting member 32 and the second supporting member 33 are matched with each other in a radial direction, and the first supporting member 32 and the second supporting member 33 together form the supporting body. The plurality of rotating bodies 31 are located radially outward of the sliding body 71.

Next, with reference to fig. 3 to 4, it is explained in detail how the actuating assembly 70 drives the rotating body 31 to position the different support surfaces radially outside the tyre building drum.

As shown in fig. 3, when the slide body 71 moves toward the bead lock unit 10 side along the spindle 1 axial direction, the plurality of rotating bodies 31 rotate in synchronization by a predetermined angle in the first direction (not shown) about the respective rotation axes C2. After the slide 71 has been moved to the set axial position, the plurality of rotating bodies 31 are positioned in the first position such that the first support surfaces F1 of the plurality of rotating bodies 31 are located radially outside the tire building drum, whereby the above-mentioned first support surfaces S1 can be formed at the support sections 30.

As shown in fig. 4, when the slide body 71 moves in the axial direction of the spindle 1 away from the bead lock unit 10, the plurality of rotating bodies 31 rotate synchronously by a predetermined angle about the respective rotation axes C2 in a second direction (not shown) opposite to the first direction. After the slide 71 has been moved to the set axial position, the plurality of rotating bodies 31 are positioned in the second position such that the second support surfaces F2 of the plurality of rotating bodies are located radially outward of the tire building drum, whereby the support segments 30 can form the above-mentioned second support surfaces S2, on which the annular recesses R matching the cross-sectional shape of the rubber reinforcement 50 are formed, on the second support surfaces S2.

Further, as shown in fig. 8, in order to avoid interference of the plurality of rotating bodies 31 during synchronous rotation, the plurality of rotating bodies 31 are spaced apart from each other, that is, when the plurality of rotating bodies 31 are in the first position or the second position, a gap M is left between adjacent rotating bodies 31.

Further, as shown in fig. 2 to 5 and 9 to 12, the support body further includes a plurality of filling members 34 extending axially and disposed at regular intervals in the circumferential direction. In particular, the filling element 34 has a third support surface N, the conformation of which corresponds to the conformation of the second support surface F2. When the plurality of rotating bodies 31 are positioned at the second position, a 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 formed by the second supporting surfaces F2 of the plurality of rotating bodies 31 and the third supporting surface N of the filling member 34. In this way, the rubber reinforcement 50 can be housed more completely in the annular recess R and can be supported well.

Because the supporting section 30 forms the 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 means of an external force (direct pressing or negative pressure adsorption), the risk that an indentation is originally generated on the PA composite layer 40 due to the existence of the gap M, or that air bubbles are easily generated between the PA composite layer 40 and the rubber reinforcement 50 due to the PA composite layer 40 being recessed into the gap due to a stress, and the PA composite layer 40 at the annular recess R is stretched again during inflation can be reduced, so that the quality of molding the tire and carcass assembly can be effectively improved, and the product yield can be improved.

Further, as shown in fig. 6 to 7, in the embodiment, the rotating body 31 is provided with an axially extending air passage L and a plurality of vent holes x communicating with the air passage L and extending radially to the second supporting surface F2, so that a portion of the PA composite layer 40 can be fitted into the annular recess R under the negative pressure.

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

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

Further, the turn-up unit 20 further includes a support plate 22, a turn-up driving assembly 23, and a guide plate 25. One end of the turn-up lever 21 is pivotally connected to the support plate 22, and the other end of the turn-up lever 21 is rotatably connected to the rolling element 24 and located outside the guide plate 25. And the turn-up driving assembly 23 is used for driving the supporting disc 22 to axially move along the outer shaft 80 so as to drive the turn-up rod 21 and the rolling element 24 to act. And the guide disc 25 is sleeved outside the outer shaft 80 and fixedly connected with the outer shaft 80. The rolling elements 24 may be in rolling engagement with the outer circumferential arcuate surface of the guide disc 25.

Further, the bead lock unit 10 includes: a plurality of supporting blocks 11 arranged in a circumferential array and disposed between the guiding disc 25 and the first supporting member 32; and a conical piston 12, the radial outer side of which forms conical surface fit with the radial inner side of the supporting block 11. The axial movement of the conical piston 12 can drive the supporting block 11 to move radially.

Next, the operation of the tire building drum of the present invention will be described in detail with reference to fig. 3 to 5 and a process for forming a run-flat tire blank in a one-step tire building machine.

In the first stage, the PA composite layer 40 is attached to a tire building drum. As shown in fig. 3, the turnup rods 21 are in the starting position, and the plurality of turnup rods 21 extend in 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 part of the PA composite layer 40 axially outside the bead lock unit 10. At the same time, the plurality of rotating bodies 31 at the supporting section 30 are positioned in the first position by the driving of the actuating assembly 70, so that the first supporting surface F1 of the plurality of rotating bodies 31 is located at the radial outer side of the tire building drum to form a first supporting surface S1 in the circumferential direction, and the first supporting surface S1 and the circumferential surface D together form an attaching surface for attaching the PA composite layer 40 to receive the PA composite layer 40.

In the second stage, two rubber reinforcing members 50 are required to be fitted at specified positions radially outside the PA composite layer 40. The above-mentioned predetermined position is a position radially aligned with the annular recess R. In the present embodiment, after the two rubber reinforcements 50 are attached to the PA composite layer 40 at the specified positions on the radially outer side, the plurality of rotating bodies 31 are switched from the above-described first position to the second position. Then, when a part of the PA composite layer 40 is received into the annular recess R together with the rubber reinforcement 50, it is ensured that the radially outer surface of the rubber reinforcement 50 is substantially flush with the outer surface of the PA composite layer 40 located outside the specified position. Thus, the ply 60 is smoothly attached to the outer surfaces of the PA composite layer 40 and the rubber reinforcement 50, and the accurate end-to-end splicing of the ply 60 is ensured. Thus, the tire forming drum provided by the invention can be used in a one-step tire forming machine to form a high-quality tire body assembly, and further can form a high-quality run-flat tire blank. As shown in fig. 4 to 5, the turnup rod 21 is still at the initial position, and the plurality of rotating bodies 31 at the supporting section 30 reach the second position under the driving of the actuating assembly 70, so that the second supporting surface F2 of the plurality of rotating bodies 31 is located at the radial outer side of the tire building drum, so that the plurality of rotating bodies 31 and the filler 34 at the supporting section 30 can cooperate to form an annular recess R matching the cross-sectional shape of the rubber reinforcement 50, and the annular recess R has a substantially continuous second supporting surface S2. By applying an external force (e.g., negative pressure adsorption) to the PA composite layer 40 and the rubber reinforcement 50 at the designated positions, the PA composite layer 40 and the rubber reinforcement 50 at the annular recess R are accommodated in the annular recess R.

There is also an alternative embodiment (not shown) for the second stage. That is, before the two rubber reinforcements 50 are attached to the specified positions on the radial outer side of the PA composite layer 40, the plurality of rotating bodies 31 are switched from the first position to the second position, and then the PA composite layer 40 at the specified positions is recessed by applying an external force (for example, negative pressure suction) and accommodated in the annular recessed portion R, and then the rubber reinforcements 50 are attached to the radial outer side of the PA composite in the annular recessed portion R, and the radial outer surfaces of the rubber reinforcements 50 and the outer surfaces of the PA composite layers 40 located outside the specified positions are ensured to be substantially flush with each other.

the tire building drum supporting section is provided with a plurality of rotating bodies, and the rotating bodies are driven to rotate, so that a first supporting surface or a second supporting surface can be selectively provided at the supporting section, the requirements of the forming process at each stage in the tire forming process are met, and high-quality run-flat tire blanks can be formed. Wherein, the first supporting surface can also effectively support the head end of the inner liner layer on the PA composite layer and the butt joint part of the head and the tail, thereby ensuring the butt joint and the sewing quality of the PA composite layer 40. An annular recess for receiving the rubber reinforcement is formed on the second support surface, thereby satisfying the molding process of the run-flat tire.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A tire building drum for building run-flat tire blanks, characterized by: the tyre building drum having an application surface for receiving a first tyre layer, the tyre building drum having two axially spaced support sections, the first tyre layer extends axially over two of the support segments, each of which is provided with a plurality of rotatable rotation bodies which are evenly distributed in the circumferential direction, the plurality of rotating bodies can be driven to rotate to be positioned at a first position or a second position, when the plurality of rotating bodies are at the first position, the support section forming a first support surface for supporting a first tyre layer, the first support surface being radially on the same circumference as the attachment surface, when the plurality of rotating bodies are at the second position, the supporting section forms an annular recess on which a second supporting surface is formed, the second supporting surface being radially lower than the attaching surface.

2. Tyre building drum according to claim 1, wherein: each of the rotating bodies has a first supporting surface and a second supporting surface, the plurality of first supporting surfaces form the first supporting surface when the plurality of rotating bodies are in the first position, and the plurality of second supporting surfaces form the second supporting surface when the plurality of rotating bodies are in the second position.

3. Tyre building drum according to claim 1, wherein: each rotating body is provided with a first supporting surface and a second supporting surface, when the rotating bodies are in the first position, the first supporting surfaces form the first supporting surface, the supporting section is further provided with a plurality of filling pieces which extend axially and are uniformly arranged at intervals in the circumferential direction, and each filling piece is provided with a third supporting surface; when the plurality of rotating bodies are in the second position, the second supporting surface and the third supporting surface cooperate to form the second supporting surface, and the second supporting surface is substantially continuous in the circumferential direction.

4. Tyre building drum according to any one of claims 1-3, wherein: the plurality of rotating bodies are arranged at intervals in the circumferential direction, and the first support surface is discontinuous in the circumferential direction.

5. Tyre building drum according to any one of claims 1-3, wherein: the tyre building drum is arranged for receiving a rubber reinforcement around the first tyre layer at the two axially spaced support sections, respectively.

6. A tyre building drum according to claim 5, characterised in that the plurality of rotary bodies are driven in rotation to switch from the first position to the second position before receiving rubber reinforcement around the first tyre layer at the two axially spaced support sections.

7. A tyre building drum according to claim 5, characterised in that the plurality of rotary bodies are driven in rotation to switch from the first position to the second position after receiving rubber reinforcement around the first tyre layer at the two axially spaced support sections.

8. A tyre building drum comprising: the main shaft and set up in two on the main shaft are half the drum, every half drum all includes: a bead locking unit for radially supporting the bead; a turn-up unit located axially outside the bead lock unit; the method is characterized in that:

each half-drum further comprises a support section located axially inside the bead locking unit; the tyre building drum having an application surface receiving a first tyre layer extending axially over both of the support segments; the support section is provided with a plurality of rotating bodies which are evenly distributed in a circumferential direction, the rotation axes of the plurality of rotating bodies are parallel to the rotation axis of the tire building drum, each rotating body has a first support surface and a second support surface, and the plurality of rotating bodies can be driven to rotate to be positioned at a first position or a second position so as to selectively enable the first support surface or the second support surface of the plurality of rotating bodies to be positioned at the radial outer side of the tire building drum.

9. Tyre building drum according to claim 8, wherein: when the rotating bodies are at the first positions, the first supporting surfaces on the supporting sections form first supporting surfaces, and the first supporting surfaces 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 surfaces on the supporting section form the second supporting surface, and the second supporting surface is concave in the radial direction relative to the attaching surface.

10. Tyre building drum according to claim 8, wherein: when the rotating bodies are at the first positions, the first supporting surfaces on the supporting sections form first supporting surfaces, and the first supporting surfaces 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 filling pieces which extend axially and are arranged in the circumferential direction, and each filling piece is provided with a third supporting surface; when the plurality of rotating bodies are positioned at the second position, the second supporting surfaces of the plurality of rotating bodies and the third supporting surface of the filling piece together form the second supporting surface, and the second supporting surface is concave in the radial direction relative to the attaching surface.

11. A tyre building drum according to claim 11, wherein: the plurality of rotating bodies and the plurality of filling members are arranged at intervals in the circumferential direction, and the second supporting surface is substantially continuous.

12. Tyre building drum according to any one of claims 8-11, wherein: the half drum also comprises an actuating assembly for driving the plurality of rotating bodies to synchronously rotate along the same direction, so that the plurality of rotating bodies can be synchronously positioned at the first position or the second position.

13. Tyre building drum according to claim 12, wherein: the supporting section is also provided with an annular supporting body, and the plurality of rotating bodies are uniformly distributed and rotatably supported on the supporting body.

14. A tyre building drum according to claim 13, wherein: the actuating assembly is accommodated in the support body and can move axially in the support body, and the plurality of rotating bodies are positioned on the radial outer side of the actuating assembly.

15. Tyre building drum according to claim 12, wherein: the actuating assembly comprises a sliding body capable of moving axially and a plurality of guide pieces which are arranged on the sliding body and are uniformly distributed along the circumferential direction; the guide pieces correspond to the rotating bodies one to one, spiral grooves are formed in the rotating bodies, and one end of each guide piece is located in each spiral groove.

16. Tyre building drum according to any one of claims 8-10, wherein: the plurality of rotating bodies are arranged at intervals in the circumferential direction, and the first support surface is discontinuous in the circumferential direction.

17. A tyre building drum according to claim 13, wherein: the supporting body comprises a first supporting piece and a second supporting piece matched with the first supporting piece in the radial direction.

18. A tyre building drum according to claim 17, wherein: the plurality of fillers are integrally disposed with the second support member or the plurality of fillers are fixedly connected to the second support member.

19. Tyre building drum according to any one of claims 8-10, wherein: an air passage communicated with an external air source is formed in the rotating body, and a plurality of vent holes communicated with the air passage are formed in the second supporting surface.