Rubber member molding method and rubber member molding device

Abstract

To provide a method and a device for sticking a tip of a rubber strip which is extruded by an extruder and passes between a pair of rollers, to a molding drum.SOLUTION: A rubber member molding method for sticking a rubber strip 12 extruded from an extruder 13 onto a surface of a rotor 11 and molding a rubber member passes the rubber strip 12 extruded from the extruder 13 between a pair of molding rollers 14 provided between the extruder 13 and the rotor 11, holds the tip of the rubber strip 12 having passed through the molding roller 14 by a holding member 20, and sticks the tip to the surface of the rotor 11.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method and an apparatus for molding a rubber member. [Background technology]

[0002] Conventionally, a method of winding a rubber strip around a molding drum to produce a rubber member has been known (see Patent Document 1). The rubber strip is formed by extrusion from an extruder. Ideally, the cross-sectional shape of the rubber strip is the same as the shape of the extrusion outlet of the extruder (the outlet of the extruder body or the hole of the mouthpiece provided on the extruder body).

[0003] In reality, however, the cross-sectional shape of the rubber strip often does not match the shape of the extrusion port due to uneven thickness of the rubber strip, etc. Therefore, even if the shape of the extrusion port is prepared to match the target cross-sectional shape of the rubber strip, it is not possible to produce the targeted rubber strip. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2008-302668 A Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, as a result of research conducted by the inventors, it has been found that passing the rubber strip extruded from an extruder between a pair of rollers makes it easier to achieve a uniform thickness of the rubber strip, and also makes it easier to achieve the desired cross-sectional shape of the rubber strip.

[0006] However, a method for attaching the tip of a rubber strip that has been extruded from an extruder and passed between a pair of rollers to a building drum has not yet been established.

[0007] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a method and an apparatus for attaching the leading end of a rubber strip, which has been extruded from an extruder and passed between a pair of rollers, to a building drum. [Means for solving the problem]

[0008] In a rubber member molding method according to an embodiment, a rubber strip extruded from an extruder is attached to a surface of a rotating body to mold a rubber member. The rubber strip extruded from the extruder is passed between a pair of molding rollers provided between the extruder and the rotating body, and a tip of the rubber strip that has passed through the molding rollers is held by a holding member and attached to the surface of the rotating body. The holding member has a breathable elastic member, an adsorption surface which is the front surface of the elastic member, and a suction section which sucks air on the rear surface side of the elastic member, and the rubber strip is adsorbed and held on the adsorption surface by sucking air from the suction section. It is characterized by:

[0009] In addition, a rubber member molding device according to an embodiment includes an extruder that extrudes a rubber strip, and a rotating body to which the rubber strip extruded from the extruder is attached. The rubber member molding device further includes a pair of rollers between the extruder and the rotating body, a holding member capable of holding a tip of the rubber strip, and a control device that controls the extruder, the rotating body, the molding rollers, and the holding member, and the control device executes control to pass the rubber strip extruded from the extruder between the pair of molding rollers, and to hold the tip of the rubber strip that has passed through the molding rollers with the holding member and attach it to the surface of the rotating body. The holding member has a breathable elastic member, an adsorption surface which is the front surface of the elastic member, and a suction section which sucks air on the rear surface side of the elastic member, and the rubber strip is held by being adsorbed to the adsorption surface by sucking air from the suction section. It is characterized by: Effect of the Invention

[0010] According to the rubber member molding method and rubber member molding device of the embodiment, the tip of the rubber strip that is extruded from the extruder and passes between the pair of rollers can be attached to the molding drum. [Brief description of the drawings]

[0011] [Figure 1] FIG. [Diagram 2]FIG. 4 is a cross-sectional view of the holding member in the cylinder extension direction. [Diagram 3] FIG. 4 is a cross-sectional view of the holding member taken along a plane parallel to the suction surface. [Figure 4] FIG. [Diagram 5] FIG. 4 is a flow diagram of a rubber member molding method. [Figure 6] FIG. 2 shows the state when the rubber strip is almost completely wound and the building drum has stopped. [Figure 7] FIG. 13 is a diagram showing a state in which the holding member holds the rubber strip. [Figure 8] 13A and 13B are diagrams showing a state when the attitude of the holding member with respect to the building drum is changed. [Figure 9] FIG. 2 shows the rubber strip being cut as the building drum rotates. [Figure 10] 1 is a flow diagram of a method for attaching a rubber strip to a building drum. [Figure 11] A diagram showing the start of molding the second rubber part. [Figure 12] 13 is a diagram showing how the tip of the rubber strip is pressed against the building drum by a holding member. [Figure 13] FIG. 13 is a diagram showing how a pressure roller presses a rubber strip against a building drum. [Figure 14] FIG. 13 is a diagram showing a state when the holding portion is separated from the building drum. [Figure 15] 13 is a diagram showing a state when the molding drum starts to rotate and the pressure roller is pressed against the molding drum. FIG. [Figure 16] FIG. 13 is a diagram showing a state when the pressure roller is separated from the building drum. [Figure 17] FIG. 13 is a diagram showing how a rubber strip is attached to a disk. [Figure 18] FIG. 2 is a diagram showing how a rubber strip is attached to a green tire. [Figure 19] FIG. 11 is a cross-sectional view of a holding member according to a modified example. [Figure 20] FIG. 11 is a front view of a rubber member molding device provided with a holding member according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The embodiments will be described with reference to the drawings. Note that the embodiments described below are merely examples, and any appropriate modifications that do not depart from the gist of the present invention are included in the scope of the present invention.

[0013] As shown in Figure 1, the rubber member molding apparatus of this embodiment has a molding drum 11 as a rotating body, an extruder 13 for a rubber strip 12, and an attachment device 10 for attaching the rubber strip 12 extruded from the extruder 13 to the molding drum 11.

[0014] The laminating device 10 is disposed between the molding drum 11 and the extruder 13. In the following description, the side where the molding drum 11 is located is referred to as the front, and the side where the extruder 13 is located is referred to as the rear. In front of the extruder 13 and below the laminating device 10, a pair of upper and lower forming rollers 14 are disposed as part of the rubber member molding apparatus.

[0015] The extruder 13 has a general structure as a rubber extruder. The extruder 13 horizontally extrudes the rubber strip 12. A pair of upper and lower forming rollers 14 rotate and pinch the rubber strip 12 extruded from the extruder 13 from above and below, thereby adjusting the shape of the rubber strip 12.

[0016] The laminating device 10 is a device for receiving the rubber strip 12 extruded from the extruder 13 and passing between a pair of upper and lower forming rollers 14 to come out in front, and laminating it on the surface of the forming drum 11 in front. On the surface of the forming drum 11, the rubber strip 12 is spirally wound to form a cylindrical rubber member, or the rubber strip 12 is wound once to form an annular rubber member. Examples of such rubber members include sidewall rubber and tread rubber.

[0017] The rotation axis of the molding drum 11 is perpendicular to the front-rear direction (the direction in which the rubber strip 12 is extruded from the extruder 13) and extends horizontally. The molding drum 11 rotates in an upward direction at a location opposite the laminating device 10.

[0018] The bonding device 10 includes a holding member 20 for holding the rubber strip 12, and a pressure roller 30 for pressing the rubber strip 12 on the forming drum 11 against the forming drum 11. When the holding member 20 is in the standby position, it is spaced apart from the forming drum 11 and is positioned to face the surface (outer peripheral surface) of the forming drum 11. The pressure roller 30 is disposed in a position further in the rotation direction of the forming drum 11 than the holding member 20. When the bonding roller 30 is in the standby position, it is spaced apart from the forming drum 11 and is positioned to face the surface of the forming drum 11.

[0019] 2 and 3, the holding member 20 has a rectangular box-shaped portion 21 with a through-hole 50 formed in the center, and a pressure roller 51 arranged inside the through-hole 50. The box-shaped portion 21 is hollow and opens toward the forming drum 11 side (the lower side in FIG. 2). A urethane sponge 22 is fitted into the opening of the box-shaped portion 21 as a breathable elastic member.

[0020] A part of the urethane sponge 22 protrudes from the opening of the box-shaped portion 21. Of the surfaces of the urethane sponge 22, the surface protruding from the box-shaped portion 21 and facing the building drum 11 is the adsorption surface 23 that adsorbs the rubber strip 12. The side surface 24 that shares a common side with the adsorption surface 23 and is perpendicular to the adsorption surface 23 is blinded by heating, painting, or other treatment, making it a non-permeable surface or a surface that is less permeable than the other surfaces. On the other hand, the adsorption surface 23 and the surface opposite the adsorption surface 23 (rear surface 25) are permeable. Therefore, air can pass from the adsorption surface 23 to the rear surface 25.

[0021] A suction hole 26 penetrating the wall of the box-shaped portion 21 is formed at one location on the side opposite to the opening of the box-shaped portion 21. The suction hole 26 is a suction portion for sucking air inside the box-shaped portion 21. A suction hose 27 is connected to the suction hole 26, and a suction pump 28 (see FIG. 4) is connected to the end of the suction hose 27. When the suction pump 28 is operated, air is sucked from the adsorption surface 23 of the urethane sponge 22, passes through the back surface 25 of the urethane sponge 22, the inside of the box-shaped portion 21, the suction hole 26, and the suction hose 27, and is sucked into the suction pump 28. Due to this mechanism, the rubber strip 12 can be adsorbed onto the adsorption surface 23 of the urethane sponge 22 by operating the suction pump 28.

[0022] It is preferable that the adsorption surface 23 of the urethane sponge 22 is treated to make the rubber less likely to stick to it, for example, by applying an anti-adhesive agent to it. Also, the urethane sponge 22 itself may have an element added thereto to make the rubber less likely to stick to it.

[0023] In the holding member 20 , a portion consisting of the holding member 20 and the urethane sponge 22 is referred to as a holding portion 29 .

[0024] The joining device 10 is composed of a holding portion 29, a pressure roller 51, a pressure roller 30, and a cylinder for moving these forward and backward. The cylinders of the joining device 10 include a first cylinder 32, a second cylinder 35 fixed to a rod 33 of the first cylinder 32, and a third cylinder 38. The first cylinder 32 and the third cylinder 38 are provided on a base member 31.

[0025] The rod 33 of the first cylinder 32 can advance and retreat obliquely downward toward the molding drum 11. A second cylinder 35 and the holding portion 29 of the holding member 20 are fixed to the rod 33 of the first cylinder 32. Therefore, the second cylinder 35 and the holding member 20 advance and retreat relative to the molding drum 11 as the rod 33 of the first cylinder 32 advances and retreats.

[0026] In addition, the rod 36 of the second cylinder 35 can advance and retreat diagonally downward toward the molding drum 11. A pressure roller 51 is provided at the tip of the rod 36 of the second cylinder 35. The pressure roller 51 is a free roller, and when pressed against the rotating molding drum 11, it rotates in the opposite direction to the rotation direction of the molding drum 11.

[0027] The pressing roller 51 advances and retreats together with the holding portion 29 of the holding member 20 as the rod 33 of the first cylinder 32 advances and retreats. In addition, the pressing roller 51 advances and retreats relative to the molding drum 11 independently of the holding member 20 as the rod 36 of the second cylinder 35 advances and retreats. The pressing roller 51 can advance to a position closer to the molding drum 11 than the holding portion 29, and can also retreat to a position farther from the molding drum 11 than the holding portion 29.

[0028] The rear part of the first cylinder 32 is supported by a support shaft 40. In addition, the front part of the first cylinder 32 is attached to a moving member 42. The moving member 42 is movable along a moving route 43 provided on the base member 31 by the action of a fourth cylinder 41 (see FIG. 4). When the moving member 42 moves along the moving route 43, the first cylinder 32 rotates slightly around the support shaft 40, and the inclination angle of the first cylinder 32 with respect to the horizontal direction is changed. By changing the inclination angle of the first cylinder 32, the attitude of the holding member 20 with respect to the building drum 11 can be changed.

[0029] The rod 39 of the third cylinder 38 can advance and retreat diagonally downward toward the molding drum 11. A pressure roller 30 is provided at the tip of the rod 39 of the third cylinder 38. The pressure roller 30 is a free roller, and when pressed against the rotating molding drum 11, it rotates in the opposite direction to the rotation direction of the molding drum 11.

[0030] As shown in Fig. 4, the extruder 13, the pair of upper and lower forming rollers 14, the forming drum 11, the suction pump 28, the cylinders 32, 35, 38, 41, etc. are connected to the control device 15. The control device 15 controls the connected devices, etc. For example, the control device 15 synchronizes the operation and rotation of the extruder 13, the forming roller 14, and the forming drum 11, and pays out from the forming roller 14 a rubber strip 12 that corresponds to the winding length due to the rotation of the forming drum 11. The control device 15 executes a rubber member forming method that will be described next.

[0031] The rubber member molding method will be described with reference to Fig. 5. At the start of the rubber member molding method, the holding member 20 and the pressure roller 30 are in a standby position away from the molding drum 11.

[0032] In the rubber member molding method, first, the control device 15 operates the extruder 13 to start rotating the pair of upper and lower molding rollers 14 (S1). As a result, the rubber strip 12 is extruded from the extruder 13 and passes between the upper and lower molding rollers 14, and advances forward.

[0033] Next, the tip of the rubber strip 12 that has passed through the forming roller 14 is attached to a predetermined position on the forming drum 11 by an operator or a holding member 20 (S2). When the rubber member is molded for the first time, the operator attaches the tip of the rubber strip 12 to the forming drum 11. When the rubber member is molded for the second or subsequent times, the holding member 20 attaches the tip of the rubber strip 12 to the forming drum 11 by a method described later.

[0034] Next, the control device 15 starts rotating the molding drum 11 (S3). This starts the attachment of the rubber strip 12 to the molding drum 11. When the molding drum 11 rotates a little and the leading end of the rubber strip 12 reaches the position for pressing by the pressing roller 30, the control device 15 advances the pressing roller 30 to press it against the rubber strip 12 on the molding drum 11 (see FIG. 15 for the state when the pressing roller 30 advances). This starts the pressing of the rubber strip 12 by the pressing roller 30.

[0035] Thereafter, the control device 15 rotates the molding drum 11 while extruding the rubber strip 12 from the extruder 13, thereby continuously attaching the rubber strip 12 to the surface of the molding drum 11. When winding the rubber strip 12 in a spiral shape around the molding drum 11, a guide member (not shown) adjacent to the molding drum 11 may be used so that the rubber strip 12 can be smoothly wound in a spiral shape around the molding drum 11. The guide member moves little by little in the axial direction of the molding drum 11 while guiding the rubber strip 12, thereby gradually moving the winding position of the rubber strip 12 around the molding drum 11 in the axial direction of the molding drum 11. As a result, the rubber strip 12 is wound in a neat spiral shape.

[0036] When a predetermined length of the rubber strip 12 has been attached to the molding drum 11 (Yes in S4), the control device 15 stops the extrusion of the rubber strip 12 from the extruder 13 and the rotation of the molding drum 11 and the molding roller 14 (S5). The state when the rotation of the molding drum 11 has stopped is shown in Figure 6.

[0037] Next, the control device 15 holds the rubber strip 12 with the holding member 20 as shown in Fig. 7 (S6). In detail, first, the control device 15 advances the holding member 20 toward the building drum 11 to bring the suction surface 23 into contact with the rubber strip 12. At this time, the control device 15 brings the front end portion 20a of the holding member 20 into contact with the position where the rubber strip 12 is to be cut. Next, the control device 15 starts suction by the suction pump 28 to cause the holding member 20 to suction the rubber strip 12.

[0038] Next, the control device 15 controls the fourth cylinder 41 to move the moving member 42 and slightly change the inclination angle of the first cylinder 32. By changing the inclination angle of the first cylinder 32, the control device 15 makes the holding member 20 stand up with respect to the tangent direction of the building drum 11, as shown in FIG. 8 (S7). When the holding member 20 is in such a position, the front end portion 20a, which is a corner portion of the holding member 20, is pressed against the rubber strip 12, causing scratches or creases in the rubber strip 12. Note that even in such a stand-up position, the rubber strip 12 is adsorbed to the entire suction surface 23 of the holding member 20.

[0039] Next, the control device 15 resumes rotation of the building drum 11 as shown in Fig. 9 while maintaining the posture of the holding member 20 and holding the rubber strip 12 with the holding member 20. Then, the rubber strip 12 is cut by being torn off starting from the scratch or crease made by the front end portion 20a of the holding member 20 (S8). The portion of the rubber strip 12 that is wound around the building drum 11 and is adjacent to the cut portion is pressed against the building drum 11 by the pressing roller 30. This completes the molding of the rubber member on the building drum 11.

[0040] Next, the control device 15 causes the holding member 20 to retract from the molding drum 11 (S9). The control device 15 may cause the holding member 20 to retract a predetermined time (the time required for the rubber strip 12 to be cut) after the rotation of the molding drum 11 is resumed, or may cause the holding member 20 to retract when a sensor detects that the rubber strip 12 has been cut. Even after retracting, the holding member 20 continues to hold the rubber strip 12. After retracting the holding member 20, the control device 15 also causes the pressure roller 30 to retract. Next, the rubber member is removed from the molding drum 11 (S9).

[0041] If the required number of rubber members have not been molded (No in S10), a second rubber member is molded.

[0042] When molding of the second rubber member starts, the holding member 20 is already holding the rubber strip 12. The control device 15 then advances the holding member 20 to attach the tip of the rubber strip 12 to a predetermined position on the molding drum 11 (S2). The attachment method at this time will be described later. The control device 15 then performs steps S3 to S9 again.

[0043] The control device 15 repeats steps S2 to S10, and ends the control when the required number of rubber members have been molded (Yes in S10). The molded rubber members are transported to a subsequent process and used as part of a tire.

[0044] Here, a method for attaching the rubber strip 12 to the building drum 11 when molding the second or subsequent rubber members will be described with reference to FIG.

[0045] At the start of molding of the second rubber member, as shown in Fig. 11, the holding member 20 and the pressure roller 30 are in a standby position away from the molding drum 11. At this time, the pressure roller 51 is stored inside the through-hole portion 50 of the holding member 20. Also, at this time, the rotation of the molding drum 11 is stopped.

[0046] 12, when starting to mold the second rubber member, first, the control device 15 advances the holding member 20 toward the molding drum 11, and the holding member 20 presses the rubber strip 12, causing the tip of the rubber strip 12 to come into close contact with the surface of the molding drum 11 (S2-1). At this time, the portion of the urethane sponge 22 of the holding member 20 that is closer to the rotation direction of the molding drum 11 than the pressure roller 51 presses the rubber strip 12 against the surface of the molding drum 11. Also, at this time, the pressure roller 51 is not in contact with the rubber strip 12.

[0047] Next, as shown in FIG. 13, the control device 15 advances the pressure roller 51 toward the building drum 11, and the pressure roller 51 presses a part of the rubber strip 12 against the surface of the building drum 11 (S2-2).

[0048] At the same time as the pressure roller 51 presses the rubber strip 12 against the forming drum 11, or after the pressure roller 51 presses the rubber strip 12 against the forming drum 11, the control device 15 stops suction by the suction pump 28 to release the adhesion of the rubber strip 12 to the adhesion surface 23 (S2-3). Furthermore, as shown in Fig. 14, the control device 15 separates the holding portion 29 of the holding member 20 from the forming drum 11 while keeping the rubber strip 12 pressed against the forming drum 11 by the pressure roller 51 (S2-4). As a result, the rubber strip 12 separates from the adhesion surface 23 of the holding portion 29.

[0049] Next, the control device 15 starts rotating the forming drum 11 (S2-5). This starts winding (attaching) the rubber strip 12 around the forming drum 11. When the forming drum 11 rotates a little and the leading end of the rubber strip 12 reaches the position for pressing by the pressing roller 30, the control device 15 advances the pressing roller 30 to press it against the rubber strip 12 on the forming drum 11, as shown in Fig. 15. This starts pressing the rubber strip 12 by the pressing roller 30.

[0050] Simultaneously with or after the pressure roller 30 starts pressing, the control device 15 moves the pressure roller 51 backward to separate it from the building drum 11, as shown in FIG. 16 (S2-6).

[0051] The above steps S2-1 to S2-6 complete the attachment of the tip of the rubber strip 12 to the molding drum 11 when molding the second or subsequent rubber members. When molding the third or subsequent rubber members, the tip of the rubber strip 12 is also attached to the molding drum 11 through steps S2-1 to S2-6.

[0052] As described above, in this embodiment, the tip of the rubber strip 12 extruded from the extruder 13 and passing between the pair of forming rollers 14 is held by the holding member 20 and attached to the surface of the forming drum 11. By using the holding member 20 in this manner, the tip of the rubber strip 12 can be attached to the surface of the forming drum 11.

[0053] Here, to carry out this method, it is sufficient to have a holding member 20 between the forming roller 14 and the forming drum 11, and there is no need to place a large device or multiple devices between the forming roller 14 and the forming drum 11. Therefore, the leading end of the rubber strip 12 that has passed between a pair of forming rollers 14 can be attached to the surface of the forming drum 11 without enlarging or complicating the equipment.

[0054] The holding member 20 has a urethane sponge 22 having an adsorption surface 23, and suction holes 26 that suck air on the back surface 25 side of the urethane sponge 22. The rubber strip 12 is adsorbed to the adsorption surface 23 by sucking air through the suction holes 26. This makes it possible to hold the rubber strip 12 reliably on the adsorption surface 23 with a simple structure. Also, by starting and stopping the suction of air through the suction holes 26, the rubber strip 12 can be freely held on the adsorption surface 23 or released from the adsorption surface 23.

[0055] In addition, a pressure roller 51 is provided adjacent to the adsorption surface 23. Then, the steps of attaching the tip of the rubber strip 12 to the surface of the building drum 11 by the adsorption surface 23, pressing the rubber strip 12 toward the building drum 11 by the pressing roller 51, and separating the adsorption surface 23 from the rubber strip 12 while the pressing roller 51 keeps the rubber strip 12 pressed down. This allows the rubber strip 12 to be reliably separated from the adsorption surface 23.

[0056] Further thereafter, a step is executed in which the rubber strip 12 is extruded from the extruder 13 and the molding drum 11 is started to rotate, while the pressure roller 51 is pressing the rubber strip 12 against the molding drum 11. In this way, the molding drum 11 starts to rotate and starts to attach the rubber strip 12 to the surface of the molding drum 11 while the rubber strip 12 is in the state it was in when it was detached from the adsorption surface 23, which is efficient.

[0057] In addition, in the rubber member molding device of this embodiment, the control device 15 passes the rubber strip 12 extruded from the extruder 13 between the pair of molding rollers 14, so that the thickness of the rubber strip 12 tends to be uniform. Furthermore, in the rubber member molding device of this embodiment, the control device 15 executes control to hold the tip of the rubber strip 12 that has passed between the pair of molding rollers 14 with the holding member 20 and attach it to the surface of the molding drum 11. In this way, the tip of the rubber strip 12 that has been extruded from the extruder 13 and passed between the pair of molding rollers 14 can be attached to the molding drum 11.

[0058] The above embodiment can be modified in various ways, and modifications of the embodiment will be described below.

[0059] <Change Example 1> In the modified example shown in Fig. 17, the laminating device 10 laminates the rubber strip 12 on a flat disk 111 instead of the forming drum 11. The disk 111 stands perpendicular to the extrusion direction of the rubber strip 12. The disk 111 is rotatable, and its rotation axis 112 is parallel to the extrusion direction of the rubber strip 12.

[0060] When attaching the rubber strip 12 to such a disk 111, the attachment device 10 operates in the same manner as in the above embodiment. However, when the holding member 20 attaches the tip of the rubber strip 12 to the disk 111, it is preferable that the holding member 20 be parallel to the disk 111.

[0061] <Change Example 2> 18, an attachment device 10 attaches a rubber strip 12 to the side of a green tire 211 before the sidewall rubber is attached. In this way, the sidewall rubber is molded on the side of the green tire 211.

[0062] During molding of the sidewall rubber, the green tire 211 is held from the inner diameter side by a holding device. As the holding device, a core member having the inner shape of the green tire 211 or the target inner shape of the finished tire, a balloon that expands by supplying air, a molding drum, a shaping drum, etc. can be used.

[0063] <Change Example 3> As the breathable elastic member provided in the holding member 20, a sponge other than the urethane sponge 22, a thick fiber material, or the like can be used.

[0064] <Change Example 4> A modified holding member 120 is shown in Figure 19. This holding member 120 has a hollow rectangular box-shaped portion 121 that is open toward the building drum 11. A urethane sponge 122 is fitted into the opening of the box-shaped portion 121 as a breathable elastic member.

[0065] A part of the urethane sponge 122 protrudes from the opening of the box-shaped portion 121. Of the surfaces of the urethane sponge 122, one surface that protrudes outside the box-shaped portion 121 and faces the forming drum 11 is an adsorption surface 123 that adsorbs the rubber strip 12. The adsorption surface 123 and the surface opposite to the adsorption surface 123 (rear surface 125) have equal breathability, but the surfaces of the urethane sponge 122 other than the adsorption surface 123 and the rear surface 125 have poor breathability due to processing such as blinding.

[0066] On the side opposite to the opening of the box-shaped portion 121, a suction hole 126 is formed penetrating the wall of the box-shaped portion 121. A suction hose 127 is connected to the suction hole 126, and a suction pump is connected to the other end of the suction hose 127. When the suction pump is operated, air is sucked from the adsorption surface 123 of the urethane sponge 122, passes through the back surface 125 of the urethane sponge 122, the inside of the box-shaped portion 121, the suction hole 126, and the suction hose 127, and is sucked into the suction pump. Due to this mechanism, the rubber strip 12 can be adsorbed onto the adsorption surface 123 of the urethane sponge 122 by operating the suction pump.

[0067] As shown in FIG. 20, the tip of the rubber strip that has been extruded from an extruder 13 (not shown) and passed between upper and lower forming rollers 14 may be adsorbed and held by this holding member 120 and affixed to the forming drum 11. [Explanation of symbols]

[0068] 10... bonding device, 11... forming drum, 12... rubber strip, 13... extruder, 14... forming roller, 15... control device, 20... holding member, 20a... front end, 21... box-shaped portion, 22... urethane sponge, 23... suction surface, 24... side, 25... back surface, 26... suction hole, 27... suction hose, 28... suction pump, 29... holding portion, 30... pressure roller, 31... base member, 32... first cylinder, 33... rod 123... suction surface, 125... rear surface, 126... suction hole, 127... suction hose, 211... green tire

Claims

1. A method for molding a rubber member in which a rubber strip extruded from an extruder is attached to a surface of a rotating body to mold a rubber member, comprising the steps of: The rubber strip extruded from the extruder is passed between a pair of forming rollers provided between the extruder and the rotating body, and a tip of the rubber strip that has passed through the forming rollers is held by a holding member and attached to the surface of the rotating body; The method for molding a rubber member is characterized in that the holding member has a breathable elastic member, an adsorption surface which is the front surface of the elastic member, and a suction portion which draws air on the back surface side of the elastic member, and the rubber strip is adsorbed and held on the adsorption surface by sucking air from the suction portion.

2. A pressure roller is provided adjacent to the attraction surface, a step of adhering the tip of the rubber strip to the surface of the rotating body by the adsorption surface; pressing the rubber strip against the rotating body by the pressing roller; a step of separating the adsorption surface from the rubber strip while the rubber strip is pressed by the pressure roller; 2. The rubber member molding method according to claim 1, further comprising the step of: starting extrusion of the rubber strip from the extruder and rotation of the rotating body while the rubber strip is pressed against the rotating body by the pressure roller, and starting attachment of the rubber strip to the surface of the rotating body.

3. A rubber member molding device having an extruder for extruding a rubber strip and a rotating body to which the rubber strip extruded from the extruder is attached, a pair of rollers between the extruder and the rotating body, a holding member capable of holding a tip of the rubber strip, and a control device for controlling the extruder, the rotating body, the forming roller, and the holding member, the control device executes control to pass the rubber strip extruded from the extruder between the pair of forming rollers, and hold a tip of the rubber strip that has passed through the forming rollers with a holding member and attach it to the surface of the rotating body; The rubber member molding device is characterized in that the holding member has a breathable elastic member, an adsorption surface which is the front surface of the elastic member, and a suction portion which draws air on the back surface side of the elastic member, and the rubber strip is adsorbed and held on the adsorption surface by sucking air from the suction portion.

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