WO2019085886A1

WO2019085886A1 - Tire building drum

Info

Publication number: WO2019085886A1
Application number: PCT/CN2018/112609
Authority: WO
Inventors: 李志军
Original assignee: 萨驰华辰机械(苏州)有限公司
Priority date: 2017-10-30
Filing date: 2018-10-30
Publication date: 2019-05-09
Also published as: CN107856333B; CN107856333A; KR20200067865A; KR102135730B1

Abstract

A tire building drum comprises a drum shaft (1) and a building assembly (2) installed thereon. The building assembly (2) comprises two side drums (20) and a center drum (21) disposed between the two side drums (20). The center drum (21) comprises two half drums (210) capable of engaging with each other in an axial direction and a synchronization unit (211) connected to the two half drums (210), respectively. Each half drum (210) comprises a plurality of circumferentially distributed first drum tiles (212) and second drum tiles (213) and a driving assembly (214) for driving the first drum tiles (212) and the second drum tiles (213) to move in the axial direction. The synchronization unit (211) is disposed to control the drum tiles of the two half drums (210) to move in the axial direction synchronously. Both of the first drum tiles (212) and the second drum tiles (213) comprise body portions (2120). The plurality of body portions (2120) of the first drum tiles (212) and those of the second drum tiles (213) are arranged with intervals and can collectively form a closed circular loop.

Description

Tire building drum

The present application claims the priority of the Chinese Patent Application, filed on Jan. 30,,,,,,,,,,,,,,,,,,,,

Technical field

The present disclosure relates to the technical field of tire building machines, for example, to a tire building drum applied to a tire building machine.

Background technique

In the upper bead step of the related tire building process, the transfer ring carrying the bead transfers the bead to a designated position of the carcass material, and the bead support unit of the tire building drum circumferentially fixes the bead to shape the tire The drum's turn-up unit wraps the beads in the carcass material. In order to avoid a shift in the position of the bead in the reverse wrapping step, a certain abutting force of the end face of the bead can be imparted by the expansion of the drum of the middle drum. At present, the drum expansion of the middle drum relies on the cylinder to drive the linkage mechanism to drive the drum to rise or fall radially. Since the initial angle of each connecting rod is the same, and in order to ensure that the bulge forms a seamless circumferential surface for the coil in the contracted state, the bulge has a gap between the bulges in the expanded state, for example, in the bulge. Near the end of the bead. In the process of forming the green tire, the gap between the middle drum near the end of the bead and the pressure at the drum is different, which causes the risk of bubbles or indentation inside the tire mouth, resulting in tire quality. accident. In addition, the drum lifting mechanism can be divided into two parts, both of which are driven by a cylinder drive, so that the drums on the left and right sides can be operated separately. Because the gas is introduced from one side and the drums on the left and right sides can be individually lifted and controlled by the cylinder, and the gas has a certain compressibility, the speed of the drums on the left and right sides will rise in the process of inconsistency. As a result, the drum on the side that is raised faster will bias the rubber material, causing the asymmetry of the rubber material, resulting in a tire quality accident.

Summary of the invention

The present disclosure provides a tire building drum having a circumferential surface and an end surface without a gap in a state in which the drum is extended, and the drums on the left and right sides of the tire building drum can be simultaneously raised and lowered.

In one embodiment, the present disclosure provides a tire building drum comprising:

a drum shaft and a molding assembly mounted on the drum shaft; the molding assembly includes two side drums and a middle drum between the two side drums; the middle drum includes two axially insertable mating a half drum and a synchronization unit connecting the two half drums; each of the half drums comprising a plurality of circumferentially distributed first and second drums and driving the first and second drums a driving assembly of the drum moving radially; the synchronizing unit is configured to control the synchronous radial movement of the drums of the two half drums; the first drum and the second drum each comprise a body portion, a plurality of The body portion of the first bulge and the body portions of the plurality of second bulges are spaced apart from each other and may together form a closed circular ring.

In an embodiment, the radial movement comprises a radial expansion or a radial contraction.

In an embodiment, the synchronization unit includes racks respectively disposed on the two half drums and gears respectively meshing with the two racks, and the two racks are oppositely disposed, the gear diameter The drum shaft is fixedly connected.

In an embodiment, the first end of each of the racks is fixed to one of the half drums, and the second end of each of the racks is a free end.

In an embodiment, the middle drum is set to contract or expand, the middle drum is in a contracted state, the first drum is located radially outward of the second drum, and the middle drum is in an expanded state. Next, the first bulge and the second bulge are on the same circumferential surface.

In an embodiment, the drive assembly includes a first support, a second support, a first slide, a plurality of second slides, and a plurality of links; the first support and the second support The pieces are respectively fixedly coupled to the side drum; the first sliding member is slidably coupled to the first supporting member, and the plurality of second sliding members are slidably coupled to the second supporting member; each of the connecting rods The two ends are respectively pivotally connected to one of the first sliding member and the plurality of the second sliding members, and the plurality of second sliding members are connected to the body portion.

In an embodiment, a plurality of fixing blocks are fixed on the first sliding member at equal intervals in the circumferential direction, and each of the fixing blocks is disposed to be pivotally connected to the connecting rod.

In an embodiment, the link includes a first link and a second link, the first link connecting the first drum through the second slider pivotally connected to the first link a second link connecting the second dam by the second sliding member pivotally connected to the second link.

In an embodiment, the angle between the first link and the axial direction is smaller than the angle between the second link and the axial direction.

In an embodiment, the first bulge is a bulge of a first radial stroke, and the second bulge is a bulge of a second radial stroke, wherein when the first bulge and the The first radial stroke is less than the second radial stroke when the second bulge is simultaneously expanded or contracted.

In an embodiment, the first dam and the second bulge further comprise a plug extending from a side of the body, the plug comprising at least one elongated finger, two of the The fingers of the half drum are interdigitated with each other such that the two middle drums are axially fitted into each other.

In an embodiment, the outer side surface and the outer circumferential surface of the ring surrounded by the plurality of body portions are seamless.

DRAWINGS

1 is a schematic view showing a first perspective structure of a tire building drum;

Figure 2 is a second perspective view of the tire building drum;

3 is a schematic view showing a third perspective structure of a tire building drum;

Figure 4 is a cross-sectional view of a tire building drum;

Figure 5 is a schematic structural view of a middle drum of a tire building drum;

Figure 6 is a partial enlarged view of the cross-sectional view of Figure 5;

7 is a schematic structural view of a first perspective of a synchronization unit;

Figure 8 is a partial structural schematic view of a tire building drum;

Figure 9 is a perspective view of the first drum of the tire building drum;

Figure 10 is a side elevational view of the bulging state of the middle drum;

Fig. 11 is a side view showing the state in which the bulge of the middle drum is contracted.

LIST OF REFERENCE NUMERALS: drum shaft-1; forming assembly-2; driving device-3; side drum-20; middle drum-21; half drum-210; synchronizing unit-211; first drum-212; -213; drive assembly - 214; first support member - 2142; first slide member - 2143; second slide member - 2144; second support member - 2145; link - 2146; first link - 2146a; Connecting rod-2146b; body portion-2120; plug portion - 2121; finger portion - 2105; rack - 2111; gear - 2112; turn-up unit - 22; bead support unit - 23; bushing - 24; Drum block assembly - 25; side drum outer cylinder - 251; side drum inner cylinder - 252; first portion - 252a; second portion - 252b; side drum piston - 253; tire building drum - 100.

Detailed ways

The embodiments of the present disclosure are described in detail below, and the examples of the embodiments are illustrated in the accompanying drawings, in which the same or similar reference numerals indicate the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are illustrative, and are not intended to be construed as limiting.

The technical solutions of the present disclosure will be described below with reference to the accompanying drawings and embodiments.

As shown in FIGS. 1 to 4, the present disclosure provides a tire building drum 100 including a drum shaft 1, a molding assembly 2 disposed on the drum shaft 1, and a driving device 3 (shown in FIG. 4). ).

As shown in FIGS. 3 to 5, the molding assembly 2 includes two side drums 20 that are symmetrically disposed, and a middle drum 21 that is located between the two side drums 20. The middle drum 21 includes two half drums 210 that can be fitted into each other in the axial direction, and the two half drums 210 are symmetrically disposed. Each side drum 20 is coupled to a half drum 210 of the two half drums 210 adjacent to the side drum 20, and a portion of each side drum 20 can be driven away from the side of the two half drums 210 adjacent to the side drum 20 Half drum 210. The two side drums 20 are fixedly connected to the drive unit 3, respectively, such that the side drums 20, together with the correspondingly connected half drums 210, can be driven by the drive unit 3 to move axially along the drum shaft 1. In an embodiment, the axial direction can be understood as the axial direction of the drum shaft 1. In one embodiment, the side drum 20 and the half drum 210 on one side of the drum shaft 1 and the side drum 20 and the half drum 210 on the other side are movable in opposite or opposite directions. Since the two half drums 210 in the molding assembly 2 can be fitted into each other, the molding assembly 2 can achieve a wider range of styling and wide dimensions, so that more sizes of tires can be formed.

As shown in FIG. 4, each of the side drums 20 is provided with a turn-up unit 22 and a bead support unit 23. The tire building drum 100 is provided as a molded carcass assembly (not shown). When the carcass material travels and fits onto the forming assembly 2, the drum shaft 1 rotates, and the driving forming assembly 2 rotates so that the carcass material is joined end to end in a ring shape. Then, the bead material is wrapped into the carcass material through the turn-up unit 22 and the bead support unit 23. Each of the side drums 20 further includes a sleeve 24 sleeved on the drum shaft 1 and a side drum cylinder assembly 25 sleeved on the outer circumferential surface of the sleeve 24. Wherein, the turn-up unit 22 and the bead support unit 23 are both disposed at one end of the side drum cylinder assembly 25 near the middle drum 21.

As shown in Fig. 4, the drive unit 3 is a screw, and the drive unit 3 can be rotated under the control of an external control unit (not shown). The driving device 3 is connected to the sleeve 24 and the side drum cylinder assembly 25 through a connecting member (not shown), and one end of the connecting member is screwed to the driving device 3, so that the driving device 3 can drive the connecting member in a state of being rotated. The axial movement causes the drive sleeve 24 to move axially along the drum shaft 1.

As shown in FIG. 4, the side drum cylinder assembly 25 operates similarly to the cylinder, and the side drum cylinder assembly 25 includes a side drum outer cylinder 251, a side drum inner cylinder 252, and a side drum inner cylinder 252 and side. A side drum piston 253 between the outer drum blocks 251. Wherein, a cavity (not shown) is formed between the side drum inner cylinder 252 and the side drum outer cylinder 251, and one end of the side drum piston 253 extends into the inner cavity. In addition, the side drum piston 253 is fixedly coupled to the sleeve 24 and the connecting member, and the side drum inner cylinder 252 abuts against the sleeve 24 and is fixedly coupled to the side drum outer cylinder 251, the side drum inner cylinder 252 and the side drum inner cylinder 251. It can slide relative to the side drum piston 253 and the sleeve 24. In one embodiment, as shown in FIG. 4, the side drum inner cylinder 252 has a generally T-shaped axial section including a fixedly connected mutually perpendicular first portion 252a and second portion 252b. Wherein, the first portion 252a extends axially and is sleeved outside the sleeve 24, the second portion 252b extends radially and perpendicular to the sleeve 24, and the second portion 252b is fixedly coupled to the side drum outer cylinder by bolts (not shown) 251. Therefore, when the inner cavity of the side drum cylinder assembly 25 is supplied with air, the side drum inner cylinder 252 and the side drum outer cylinder 251 can reciprocate together along the drum shaft 1 on the sleeve 24 opposite the side drum piston 253. At the same time, the reverse wrapping unit 22 and the bead supporting unit 23 are axially moved together. Therefore, a portion of the side drum 20, that is, the side drum inner cylinder 252 and the side drum outer cylinder 251 can move away from the corresponding half drum 210 with respect to the sleeve 24 of the side drum 20 and the side drum piston 253. When a part of the side drum 20 is separated from the half drum 210, a space is formed between the two, so that other station devices can be moved into the space to carry out the process steps of the carcass material, so that the sidewall can be composited to The carcass material is formed to form a carcass assembly. When the carcass material is being wrapped, a portion of the side drum 20 moves closer to the half drum 210, and then the two half drums 210 are driven by the driving device 3 to bring them closer to each other and fit to complete the inflation of the carcass assembly. Stereotype steps.

As shown in FIGS. 2 to 6, the middle drum 21 further includes a synchronizing unit 211 that connects the two half drums 210, and the synchronizing unit 211 can control the dams of the two half drums 210 (the first bulge 212 and the second bulge). 213) Synchronously moving in the radial direction. The two half drums 210 of the middle drum 21 are connected to the sleeves 24 of the two side drums 20, respectively, so that each side drum 20 can be connected to the half drum 210 of the two half drums 210 on the side close to the side drum 20.

As shown in FIGS. 5 to 6, each of the half drums 210 is in a contracted state, that is, an initial state, at the time of winding, and at this time, the middle drum 21 has a first outer diameter size. When the bead turn-up is performed, the half-drum 210 expands outward and is finally in an expanded state, at which time the middle drum 21 has a second outer diameter size. Wherein the second outer diameter dimension is greater than the first outer diameter dimension. Each of the half drums 210 includes a plurality of first and

second drums

212 and 213 disposed circumferentially and a drive assembly 214 that secures the sleeve 24 of the side drums 20. Wherein, the drive assembly 214 can drive the first drum 212 and the second drum 213 to move radially (away from or near the drum shaft 1) to enable the middle drum 21 to achieve two different outer diameter dimensions.

As shown in FIG. 5 and FIG. 6, the driving assembly 214 includes a first supporting member 2142, a second supporting member 2145, a first sliding member 2143, a plurality of second sliding members 2144, and a plurality of connecting rods 2146;

The first support member 2142 and the second support member 2145 respectively fix the sleeve 24 of the side drum 20; the first slider 2143 is slidably coupled to the first support member 2142, and the plurality of second slider members 2144 are respectively coupled to the second support member. 2145 sliding connection, two ends of each link 2146 are respectively pivotally connected to one of the first sliding member 2413 and the plurality of second sliding members 2144 (ie, one end of the plurality of connecting rods 2146 is commonly connected to a first sliding member 2413 The other ends of the plurality of links 2146 are respectively connected to the plurality of second sliders 2144). The first support member 2142 extends horizontally and has an annular shape, and is sleeved outside the drum shaft 1 and axially connected to the sleeve 24 . The second support member 2145 is annular and sleeved on the periphery of the end of the sleeve 24 and radially connected to the sleeve 24. Since the two ends of each of the links 2146 are pivotally connected to the first slider 2413 and the second slider 2144, respectively, the axial movement of the first slider 2143 can drive the radial movement of the second slider 2144, The radial movement of the first bulge 212 and the second bulge 213 can be further driven.

Since the first support member 2142 and the second support member 2145 are both fixedly coupled to the sleeve 24, when the axial position of the sleeve 24 relative to the drum shaft 1 is constant, the first support member 2142 and the second support member 2145 are also The position of the second slider 2144 radially slidably disposed on the second support member 2145 is also not axially displaced with respect to the drum shaft 1 with respect to the position of the drum shaft 1.

As shown in FIG. 5 and FIG. 6 and in conjunction with FIG. 4 and FIG. 10 to FIG. 11, the first sliding member 2143 is axially moved inwardly, and the one end of the plurality of connecting rods 2146 pivotally connected to the first sliding member 2143 is also axially Moving inwardly, and driving the plurality of links 2146 to be pivotally connected to the other ends of the plurality of second sliders 2144, respectively, to move radially inward, so that the plurality of second sliders 2144 also move in the radial direction to be close to the drum shaft. 1. The plurality of first and

second dams

212, 213, which are connected to the plurality of second sliders 2144, are moved in the radial direction to be adjacent to the drum shaft 1, and thus the plurality of first dams 212 and second dams. The diameter corresponding to 213 becomes smaller, and thus the contraction of the middle drum 21 is completed.

In an embodiment of the present disclosure, the plurality of first bulges 212 and second bulges 213 are each coupled to a respective second slider 2144. In one embodiment, the first bulge 212 is a large bulge, the second bulge 213 is a small bulge, and the radial travel of the first bulge 212 is less than the radial travel of the second dam 213.

As shown in FIG. 5 and FIG. 6, a plurality of fixing blocks 2147 are fixed on the first sliding member 2143 at equal intervals in the circumferential direction, and the plurality of fixing blocks 2147 are disposed to be pivotally connected to the plurality of connecting rods 2146, respectively. The connecting rod 2146 includes a first connecting rod 2146a and a second connecting rod 2146b. The first connecting rod 2146a is pivotally connected to the first bulge 212 by a second sliding member 2144 pivotally connected to the first connecting rod 2146a, and the second connecting rod 2146b passes The second sliding member 2144 pivotally connected to the second link 2146b is pivotally connected to the second bulge 213. As shown in Fig. 6, C is a line segment parallel to the drum axis, and the angle between the first link 2146a and the second link 2146b and the C line segment is α, β, respectively. In order to achieve a difference in radial travel between the first bulge 212 and the second bulge 213, α is less than β. Therefore, when the first bulge 212 and the second bulge 213 are radially moved to the extreme position (outermost side), the first bulge 212 and the second bulge 213 are located on the same circumferential surface, that is, the limit position of the expansion is at The radial dimensions are the same. When the driving assembly 214 drives the first dam 212 and the second dam 213 to transition from the expanded state to the contracted state, since the radial travel of the first bulge 212 is smaller than the radial travel of the second bud 213, When the first bulge 212 is in its own contraction limit position, the second tampon 213 can continue to contract frequently until it reaches its own contraction limit position, and the second bud 213 is located inside the first bulge 212, ie, the second The corresponding radial dimension of the drum 213 is smaller than the corresponding radial dimension of the first bulge 212. In an embodiment, when the first pad 212 and the second pad 213 are simultaneously raised, the outer surfaces of the first pad 212 and the second pad 213 can be seamlessly docked, when the first pad 212 and the first When the two drums 213 are simultaneously contracted, the second drum 213 is contracted under the first drum 212.

In an embodiment, in order to ensure that the first drum 212 and the second drum 213 are different in radial stroke, the length of the first link 2146a, the second link 2146b may be changed, or the first link 2146a may be changed respectively. The pivotal points of the two ends are in the radial and axial positions, or the pivotal points of the two ends of the second link 2146b are in the radial and axial positions, and the detailed structure will not be described herein.

Referring to FIG. 4 to FIG. 9 , the first drum 212 and the second drum 213 are similar in structure, and each includes a body portion 2120 fixedly coupled to the second sliding member 2144 and a plug extending from a side of the body portion 2120. Part 2121. The body portions 2120 of the plurality of first and

second bristles

212, 213 are spaced apart from one another in the expanded state of the bulge and together form a closed loop. In an embodiment, the side end surface and the outer circumferential surface of the ring are seamless, that is, the adjacent first drum 212 and the second body 213 of the second drum 213 are closely connected, as shown in FIG. At and at B. Therefore, in the reverse wrapping process, the plurality of first bulges 212 and the second bulge 213 of the two half drums 210 are in an expanded state, the body portion 2120 can provide an abutting force to the end faces of the bead, and the body portion 2120 is formed. The circular ring also has no gap on the circumferential surface, so that the body portion 2120 of the two half drums 210 can be prevented from indenting the tire material during the reverse wrapping process, thereby avoiding the risk of bubbles or indentations on the inside of the embryonic core.

8 and 9, the insertion portions 2121. The finger portion 2105 of the second bulge 213. The two half drums 210 are mutually staggered by the oppositely disposed fingers 2105 to achieve an axial mutual engagement of the two half drums 210.

Since the insertion portion 2121 of the first bulge 212 and the second tiling 213 of the present disclosure is indirectly fixed to the driving assembly 214, and the driving assembly is fixed to the sleeve 24, the insertion portion 2121 can be axially moved by the sleeve 24 to mutually The mating fit allows the socket portion 2121 to be used to change the width of the shoulder between the two half drums 210, thereby completing the inflation setting step of the carcass assembly.

As shown in FIGS. 4 and 7, the synchronizing unit 211 includes two racks 2111 which respectively connect the two half drums 210, and a gear 2112 which is located between the two racks 2111 and meshes with the two racks 2111, respectively. The first end of each rack 2111 is fixed to the first sliding member 2143 of one half drum 210, and the different racks 2111 are fixedly connected with different half drums 210, and the second end of each rack 2111 is axially Free extension. The gear 2112 is located at an axial center position of the two half drums 210, and is fixedly coupled to the drum shaft 1 in the radial direction. When the driving assembly 214 of the two half drums 210 respectively controls the axial movement of the corresponding first slider 2143, the rack 2111 fixed to the first slider 2143 of the two half drums 210 also moves axially. Since the gears 2112 are respectively engaged with the two racks 2111, the moving speed of the two racks should be the same. Therefore, even if the moving speed of the first slider 2143 of one of the half drums 210 is too slow or cannot be moved due to a gas path failure or the like, the first slider 2143 of the other half drum 210 moves correspondingly due to the presence of the gear 2112. Slow or not moving. Therefore, the connecting rod 2146 pivoting the first sliding member 2143 is also not moved, and thus the second sliding member 2144, the first bulge 212 and the second bulging 213 are no longer moved radially, so the synchronization unit 211 of the present disclosure may The plurality of drums of the two half drums 210 are controlled to move synchronously in the radial direction to avoid the inconsistent expansion speed of the drums on both sides, thereby avoiding the lifting of the rubber on the one side of the lifting drum, which causes the rubber material to be displaced, resulting in the asymmetry of the carcass material. , causing tire quality accidents.

The present disclosure drives the first damper 212 and the second bulge 213 to radially expand and contract by the contraction assembly 214, and by setting the radial strokes of the first bulge 212 and the second bulge 213 to be different, such that the extreme position of the expansion Wherein the first bulge 212 and the second bulge 213 are located on the same circumferential surface, and at the limit position of the contraction, the second dam 213 may be contracted into the ring surrounded by the first bulge 212; 212. When the second bulge 213 is expanded to the limit position, the middle drum 21 has no gap near the two end faces of the side drum 20 and the circumferential surface, so that the gap is prevented from being indented when the bead is abutted against the bead. The synchronous lifting and lowering of the two half drums 210 is controlled by the synchronizing unit 211, so that the carcass material is not biased, the asymmetry of the carcass material is avoided, and the quality of the tire is improved.

In the description of the embodiments, the description of the terms "in this embodiment", "in an embodiment", "in an embodiment", or the like, means that the features or characteristics described in connection with the embodiment are included in at least the present disclosure. In one embodiment. In the embodiments, the schematic expressions of the above terms are not necessarily referring to the same embodiments. Moreover, the described features or characteristics may be combined in any suitable manner in any one or more embodiments.

Claims

A tire building drum comprising: a drum shaft (1) and a molding assembly (2) mounted on the drum shaft (1); the molding assembly (2) comprising two side drums (20) and two a middle drum (21) between the side drums (20); the middle drum (21) includes two half drums (210) axially interfitably fitted to each other and two half drums (210) respectively connected Synchronization unit (211); each of the half drums (210) includes a plurality of circumferentially distributed first and second dams (212) and a second dam (212) and drives the first dam (212) and a second drum (213) radially moving drive assembly (214); the synchronization unit (211) is configured to control the simultaneous radial movement of the drums of the two half drums (210); the first The drum (212) and the second drum (213) each include a body portion (2120), a body portion (2120) of the plurality of first drums (212), and a plurality of the second drums ( The body portions (2120) of 213) are spaced apart from each other and may together form a closed ring.
The tire building drum according to claim 1, wherein said synchronizing unit (211) includes racks (2111) respectively provided on the two of said half drums (210) and respectively with said two racks ( 2111) Engaged gears (2112), two of the racks (2111) are oppositely disposed, and the gears (2112) are radially fixedly coupled to the drum shaft (1).
The tire building drum according to claim 2, wherein a first end of each of said racks (2111) is fixedly coupled to one of said half drums (210), and said first of said racks (2111) The two ends are free ends.
The tire building drum according to claim 1, wherein said middle drum (21) is set to contract or expand; said middle drum (21) is in a contracted state, said first drum (212) is located in said The radially outer side of the second bulge (213), in the expanded state, the first bulge (212) and the second bulge (213) are on the same circumferential surface.
The tire building drum of claim 4, wherein the drive assembly (214) includes a first support (2142), a second support (2145), a first slide (2143), and a plurality of second slides a piece (2144) and a plurality of links (2146); the first support member (2142) and the second support member (2145) are fixedly coupled to the side drum (20), respectively; the first sliding member (2143) a sliding connection with the first support member (2142), each of the plurality of second sliding members (2144) being slidably coupled to the second support member (2145); two of each of the connecting rods (2146) The ends are respectively pivotally connected to one of the first sliding member (2143) and the plurality of the second sliding members (2144), and the plurality of second sliding members (2144) are connected to the body portion (2120) .
The tire building drum according to claim 5, wherein the first slider (2143) is fixed with a plurality of fixing blocks (2147) equidistantly circumferentially, and each of the fixing blocks (2147) is set to The connecting rod (2146) is pivotally connected.
The tire building drum according to claim 6, wherein said link (2146) includes a first link (2146a) and a second link (2146b), said first link (2146a) passing said The second slider (2144) pivotally connected to the first link (2146a) is connected to the first drum (212), and the second link (2146b) is passed through the second link (2146b) The pivoted second slider (2144) is coupled to the second drum (213).
The tire building drum according to claim 7, wherein an angle between the first link (2146a) and the axial direction is smaller than an angle between the second link (2146b) and the axial direction.
The tire building drum according to claim 1, wherein said first drum (212) is a first radial stroke of the drum, and said second drum (213) is a second radial stroke of the drum. Wherein the first radial stroke is less than the second radial stroke when the first bulge (212) and the second bulge (213) are simultaneously expanded or contracted.
The tire building drum according to claim 1, wherein said first drum (212) and said second drum (213) further comprise a plug portion (2121) extending from a side of the body portion (2120). The plug portion (2121) includes at least one elongated finger portion (2105), and the finger portions (2105) of the two half drums (210) are interlaced with each other to make the two middle drums (21) The axial mutual engagement fits.
The tire building drum according to claim 1, wherein an outer side surface and an outer circumferential surface of said ring surrounded by said plurality of said body portions (2120) are seamless.