Molding drum machine

Abstract

The present invention provides a molding drum device that can shorten the time required to mold sheet-like rubber members into cylindrical shapes. [Solution] The molding drum device 10 is a molding drum device 10 which joins the front end and rear end of a sheet-like rubber member S to form a cylindrical rubber member on the outer surface of a drum formed of a plurality of segments 11, wherein at least one of the plurality of segments 11 is a rubber member adhesive surface 21a which forms a part of the outer surface of the drum, a pressing member 22 which presses the sheet-like rubber member S against the rubber member adhesive surface 21a, a recess 26 which accommodates the pressing member 22, and a moving mechanism 23 which moves the pressing member 22 between the recess 26 and the outside of the sheet-like rubber member S, and the moving mechanism 23 is a cylinder 50 and a guide part 30 which is connected to a piston rod 51 and receives power in one direction from the piston rod 51 to move the pressing member 22 between the recess 26 and the rubber member adhesive surface 21a.

Description

【Technical Field】 【0001】 The present invention relates to a molding drum device. 【Background Art】 【0002】 In the manufacturing process of pneumatic tires, there is a process in which a sheet-shaped rubber member is wound around a molding drum device and formed into a cylindrical shape. When the sheet-shaped rubber member starts to be wound around the molding drum device, the front end of the sheet-shaped rubber member is attached to the surface of the molding drum device. The front end of the sheet-shaped rubber member only contacts the surface of the molding drum device and adheres to the surface of the molding drum device with a certain strength. 【0003】 However, when the adhesiveness of the sheet-shaped rubber member is small, the front end of the sheet-shaped rubber member may shift on the surface of the molding drum device. And if the front end of the sheet-shaped rubber member remains shifted, the completed tire will become a defective product. 【0004】 Therefore, in Patent Document 1 below, at least one of a plurality of segments provided side by side in the drum circumferential direction includes a first small segment and a second small segment, and the first small segment can take a first state in which the outer surface coincides with the second small segment and a second state in which at least a part of the first small segment is arranged outside the second small segment in the drum radial direction. A molding drum device has been proposed. 【0005】 In such a molding drum device, the front end of the sheet-shaped rubber member attached to the outer peripheral surface of the drum is sandwiched between the first small segment and the second small segment to prevent the front end of the sheet-shaped rubber member from shifting. 6]]【Prior Art Documents】 【Patent Documents】 【0006】 【Patent Document 1】 Japanese Unexamined Patent Application Publication No. 2024-44668 【Summary of the Invention】 [Problems that the invention aims to solve] 【0007】 However, in the molding drum apparatus described above, in order for the first sub-segment to change state between the first and second states, the first sub-segment must move radially along the drum and also move around the axis of the shaft member provided on the first sub-segment. Therefore, it takes time to change the state of the first sub-segment between the first and second states, which is a problem because it takes time to mold the sheet-like rubber member into a cylindrical shape. 【0008】 Therefore, the object of the present invention is to provide a molding drum device that can shorten the time required to press a sheet-like rubber member against the molding drum device, thereby shortening the time required to mold the sheet-like rubber member into a cylindrical shape. [Means for solving the problem] 【0009】 The present invention includes embodiments shown below. 【0010】 [1] A molding drum apparatus comprising a drum having a plurality of segments arranged in the circumferential direction of the drum, a sheet-like rubber member wrapped around the outer surface of the drum, and the front end and rear end of the sheet-like rubber member joined together to form a cylindrical rubber member on the outer surface of the drum, wherein at least one of the plurality of segments is a front end holding segment, the front end holding segment comprises a rubber member attachment surface that forms a part of the outer surface of the drum, a pressing member that presses the sheet-like rubber member against the rubber member attachment surface, a recess that is recessed inward in the radial direction of the drum from the rubber member attachment surface and accommodates the pressing member, and a moving mechanism that moves the pressing member between the recess and the outside of the sheet-like rubber member attached to the rubber member attachment surface, the moving mechanism comprising a cylinder that moves a piston rod in the axial direction, and a guide portion connected to the piston rod and receiving power in one direction from the piston rod to move the pressing member between the recess and the rubber member attachment surface. 【0011】 [2] The molding drum apparatus according to [1] above, wherein the guide section is equipped with a parallel link mechanism. 【0012】 [3] The molding drum apparatus according to [2], further comprising a first stopper that restricts the movement of the parallel link mechanism that moves the pressing member from the rubber member attachment surface to the recess. 【0013】 [4] The molding drum apparatus according to [2] or [3] above, further comprising a second stopper that restricts the movement of the parallel link mechanism that moves the pressing member from the recess to the rubber member attachment surface. 【0014】 [5] The molding drum apparatus according to any one of [1] to [4] above, wherein the pressing member presses a position away from the rear end of the sheet-like rubber member attached to the rubber member attachment surface, and includes a detection unit that detects the front end of the sheet-like rubber member while the pressing member is pressing the sheet-like rubber member. 【0015】 [6] The molding drum apparatus according to any one of [1] to [5] above, wherein the arithmetic mean roughness of the portion of the pressing member that contacts the sheet-like rubber member is greater than the arithmetic mean roughness of the portion of the front end holding segment that is attached to the rubber member and faces the pressing member with the sheet-like rubber member in between. [Effects of the Invention] 【0016】 According to this embodiment, the time required for pressing the sheet-shaped rubber member against the molding drum device can be reduced, thereby shortening the time required to mold the sheet-shaped rubber member into a cylindrical shape. [Brief explanation of the drawing] 【0017】 [Figure 1] A perspective view of the molding drum device during the diameter expansion process. [Figure 2] A view of the molding drum device in the direction of the drum axis during the diameter expansion process. [Figure 3] A view of the molding drum device from the drum axis direction when the diameter is reduced. [Figure 4] The figure shows the front-end holding device as viewed from the drum axis direction, when the pressing member is in the housing position. [Figure 5] The figure shows the moving mechanism as viewed from the outside in the drum diameter direction. [Figure 6] Perspective view of the segment body of the front-end holding segment. [Figure 7] The figure shows the front-end holding device as viewed from the drum axis direction, when the pressing member is in the pressing position. [Figure 8] Block diagram showing the control configuration of the molding drum device. [Figure 9] Flow chart showing the process of the molding drum device molding a cylindrical rubber member. [Figure 10] The figure explains the method of winding the sheet-like rubber member around the molding drum device, and shows the state when the sheet-like rubber member is attached to the first rubber member attachment surface of the segment body. 【Embodiments for Carrying Out the Invention】 【0018】 The embodiments will be described based on the drawings. Note that the embodiments described below are merely examples, and those appropriately modified without departing from the gist of the present invention are included in the scope of the present invention. 【0019】 (1) Overall configuration of the molding drum device 10 The molding drum device 10 shown in FIGS. 1 and 2 is a drum for molding a cylindrical rubber member by winding a sheet-like rubber member S around its outer peripheral surface. The sheet-like rubber member S is made of rubber, but may contain something other than rubber such as a cord made of metal or organic fiber inside. The sheet-like rubber member S is a part of a pneumatic tire. The cylindrical rubber member formed from the sheet-like rubber member S becomes a part of a pneumatic tire. 【0020】 As shown in Figures 1 and 2, the molding drum apparatus 10 comprises a drum 12 composed of a plurality of segments 11 arranged in the circumferential direction of the drum, and a front end holding device 13. The molding drum apparatus 10 is controlled by a control unit 60. 【0021】 Each segment 11 constituting the drum 12 is a long member in the direction of the drum axis. The outer surface of each segment 11 in the radial direction of the drum (hereinafter referred to as the "outer surface") is a curved surface. Each outer surface 11a is part of the outer circumferential surface of the molding drum device 10. The outer circumferential surface of the molding drum device 10 is a single cylindrical surface that forms the outer circumference of the molding drum device 10 and becomes the molding surface during molding. 【0022】 When viewed from the outside in the radial direction of the drum, both ends of each segment 11 in the circumferential direction of the drum have a concave-convex shape portion 11b in which concave and convex shapes are arranged alternately in the direction of the tire axis. The concave-convex shape portions 11b of adjacent segments 11 are configured to interlock with each other. 【0023】 Furthermore, each segment 11 is made of a metal such as stainless steel. The outer surface 11a of each segment 11 is a smooth metal surface. Each segment 11 is attached to a segment holding member (not shown) which is located on the inside in the radial direction of the drum. 【0024】 Inside the molding drum device 10, a known segment drive device 63 (see Figure 8), consisting of a cylinder or the like, is provided. When the segment drive device 63 is driven, each segment 11 moves in the radial direction of the drum. 【0025】 As the segments 11 move outward in the radial direction of the drum, the molding drum device 10 expands in diameter. Diameter expansion means that the diameter increases. Figures 1 and 2 show the molding drum device 10 when it has expanded in diameter. As shown in Figures 1 and 2, as the molding drum device 10 expands in diameter, adjacent segments 11 come into contact with each other, and the outer surfaces 11a of all segments 11 become one cylindrical surface. In this state, the sheet-like rubber member S is wrapped around it, and the cylindrical rubber member is molded. 【0026】 Figure 3 shows the molding drum device 10 when its diameter is reduced. Diameter reduction refers to a decrease in diameter. As the segments 11 move inward in the drum's radial direction, the molding drum device 10 reduces in diameter as shown in Figure 3. When the molding drum device 10 reduces in diameter, segments 11 that have moved significantly inward in the drum's radial direction and segments 11 that have moved slightly inward in the drum's radial direction are arranged alternately in the drum's circumferential direction. When the molding drum device 10 reduces in diameter after the cylindrical rubber member has been molded on the molding surface, a gap is created between the cylindrical rubber member and the outer surface 11a of the segments 11, making the cylindrical rubber member removable. 【0027】 One of these segments 11 is replaced by a front end holding segment 20. The front end holding segment 20 is part of a front end holding device 13 for holding the front end Se of the sheet-like rubber member S. The front end Se of the sheet-like rubber member S is the leading edge on the winding start side of the sheet-like rubber member S. The rear end of the sheet-like rubber member S is the leading edge on the winding end side of the sheet-like rubber member S. 【0028】 (2) Front end holding segment 20 The front end holding segment 20 comprises a segment body 21, a pressing member 22, and a moving mechanism 23. 【0029】 As shown in Figure 1, the segment body 21, like the multiple segments 11, is a member that is long in the direction of the drum axis and is arranged in the circumferential direction of the drum together with the multiple segments 11. 【0030】 (3) Segment body 21 The segment body 21 is provided to be movable in the drum radial direction together with the other segments 11. The segment drive device 53 that moves the segment body 21 in the drum radial direction is the same as the segment drive device 53 that moves the other segments 11 in the drum radial direction. When the segment body 21 moves in the drum radial direction together with the other segments 11, the retaining member 22 and the moving mechanism 23 also move in the drum radial direction together with the segment body 21. 【0031】 The outer surface of the segment body 21 in the drum radial direction is the rubber member attachment surface 21a. The rubber member attachment surface 21a, together with the outer surface 11a of the segment 11, constitutes the outer circumferential surface of the molding drum device 10, and the sheet-like rubber member S is attached to it. 【0032】 As shown in Figure 6, the segment body 21 has a recess 26 formed in a shape into which the retaining member 22 fits. The recess 26 extends in the direction of the drum axis and opens onto the rubber member attachment surface 21a of the segment body 21. 【0033】 The recess 26 is positioned off-center to one side in the drum circumferential direction from the center of the drum circumferential direction on the rubber member attachment surface 21a. In other words, the recess 26 is provided on the segment body 21 such that the distance from the recess 26 to one end of the segment body 21 in the drum circumferential direction is longer than the distance from the recess 26 to the other end of the segment body 21 in the drum circumferential direction. The rubber member attachment surface 21a of the segment body 21 is divided in the drum circumferential direction by the recess 26. 【0034】 The rubber member attachment surface 21a has a first rubber member attachment surface 21aa formed on one side in the circumferential direction of the drum, and a second rubber member attachment surface 21ab formed on the other side in the circumferential direction of the drum, the second rubber member attachment surface 21ab having a shorter length in the circumferential direction of the drum than the first rubber member attachment surface 21aa. 【0035】 As shown in Figures 1 and 4, the retaining member 22 is housed in the recess 26 of the segment body 21, so that the rubber member attachment surface 21a of the segment body 21 and the outer surface 22a of the retaining member 22 become a continuous curved surface. The rubber member attachment surface 21a and the outer surface 22a of the retaining member 22, together with the outer surface 11a of the segment 11, constitute the outer circumferential surface of the molding drum device 10, to which the sheet-like rubber member S is attached. 【0036】 In Figure 4, reference numeral 61 denotes a detection unit that detects whether a sheet-like rubber member S is attached to the rubber member attachment surface 21a of the segment body 21. The detection unit 61 is, for example, a laser sensor. 【0037】 (4) Retaining member 22 The retaining member 22 has an inner surface 22b that faces the outer surface 22a in the drum radial direction and is shorter in the drum circumferential direction than the outer surface 22a. In addition, the retaining member 22 is provided on the side of the first rubber member attachment surface 21aa with an inclined surface 22c that slopes so that it becomes longer in the drum circumferential direction as it approaches the outer surface 22a from the inner surface 22b. 【0038】 Furthermore, on the first rubber member attachment surface 21aa side of the recess 26 in which the retaining member 22 is housed, an inclined wall 26a is provided that slopes such that the length of the recess 26 in the drum circumferential direction increases as it moves outward in the drum radial direction. The inclined surface 22c of the retaining member 22 is positioned approximately parallel to the inclined wall 26a of the recess 26 at a constant distance in the drum circumferential direction when the retaining member 22 is housed in the recess 26. 【0039】 The segment body 21 and the retaining member 22 are made of metal such as stainless steel or iron. Preferably, at least the inner surface 22b of the retaining member 22 is roughened by sandblasting or the like. Preferably, the inner surface 22b of the retaining member 22 has a larger arithmetic mean roughness Ra than the first rubber member attachment surface 21aa of the segment body 21, the second rubber member attachment surface 21ab, and the outer surface 11a of the segment 11. 【0040】 Furthermore, the arithmetic mean roughness Ra of the first rubber member attachment surface 21aa and the second rubber member attachment surface 21ab of the segment body 21 is the same as the outer surface 11a of the other segments 11. The arithmetic mean roughness Ra of the outer surface 22a of the retaining member 22 may be the same as the first rubber member attachment surface 21aa and the second rubber member attachment surface 21ab and the outer surface 11a of the segments 11. Also, the arithmetic mean roughness Ra of the outer surface 22a of the retaining member 22 may be the same as the inner surface 22b of the retaining member 22. 【0041】 For example, the arithmetic mean roughness Ra of the inner surface 22b of the pressing member 22 can be set to 10 μm or more and 15 μm or more, and the arithmetic mean roughness Ra of the first rubber member attachment surface 21aa of the segment body 21, the second rubber member attachment surface 21ab, and the outer surface 11a of the segment 11 can be set to 3 μm or more and 5 μm or less. 【0042】 In this specification, the arithmetic mean roughness Ra is measured in accordance with JIS B0601 2001 edition. 【0043】 The retaining member 22 is movable relative to the segment body 21. A moving mechanism 23 for moving the retaining member 22 is provided on both sides in the drum axis direction. 【0044】 Since the moving mechanisms 23 on both sides in the drum axis direction have the same basic configuration except that they are arranged symmetrically with respect to a plane that passes through the axial center of the molding drum device 10 and is perpendicular to the drum axis direction, we will explain one of the moving mechanisms 23 and omit the explanation of the other moving mechanism 23. 【0045】 (5) Moving mechanism 23 The moving mechanism 23 includes a cylinder 50 that moves the piston rod 51 in the axial direction, and a guide section 30 that is connected to the piston rod 51 and receives axial power from the piston rod 51. 【0046】 The guide section 30 receives power in one direction from the piston rod 51 of the cylinder 50 and moves the pressing member 22 between a position in which the pressing member 22 is housed in the recess 26 as shown in Figures 2 and 4 (hereinafter, this position may also be called the housed position) and a position in which the sheet-like rubber member S is placed on the first rubber member attachment surface 21aa of the segment body 21 and presses the sheet-like rubber member S against the first rubber member attachment surface 21aa as shown in Figure 7 (hereinafter, this position may also be called the pressing position). 【0047】 The storage position is set so that the outer surface 22a of the pressing member 22 is a continuous curved surface with the rubber member attachment surface 21a of the segment body 21. The pressing position is set so that it is a predetermined length away from the recess 26 in the circumferential direction of the drum, and the inner surface 22b of the pressing member 22 presses the portion of the sheet-like rubber member S that is a predetermined length behind the front end Se. 【0048】 Furthermore, it is preferable that the pressing position where the inner surface 22b of the pressing member 22 presses against the sheet-like rubber member S is 10 mm or more and 20 mm or less from the front end Se of the sheet-like rubber member S. 【0049】 As shown in Figures 4 and 5, the guide section 30 comprises a plate section 31, a first arm 32, a second arm 33, and an arm connecting member 34. 【0050】 The plate portion 31 is attached to the segment holding member 14, which holds the front end holding segment 20, via bolts. The plate portion 31 can move together with the front end holding segment 20 and the segment holding member 14 in the radial direction of the drum. 【0051】 The plate portion 31 is rotatably mounted to the first arm 32, the second arm 33, and the cylinder 50. 【0052】 Specifically, as shown in Figure 4, one end 32a of the first arm 32 is rotatably connected to the plate portion 31 at a position on the side of the first rubber member attachment surface 21aa, relative to the recess 26 of the segment body 21 when viewed from the direction of the drum axis. The other end 32b of the first arm 32 is rotatably connected to the arm connecting member 34. 【0053】 One end 33a of the second arm 33 is rotatably connected to the plate portion 31 between the recess 26 of the segment body 21 and one end 32a of the first arm 32, as viewed from the direction of the drum axis. For example, one end 33a of the second arm 33 is rotatably connected to the plate portion 31 on the inner side of the inclined wall 26a of the recess 26 in the drum radial direction. The other end 33b of the second arm 33 is rotatably connected to the arm connecting member 34. 【0054】 As is clear from the above description, the arm connecting member 34, together with the plate portion 31, the first arm 32, and the second arm 33, constitutes a parallel link mechanism. 【0055】 The ends of the retaining member 22 are connected to the arm connecting member 34 of the moving mechanism 23, which is provided on one side of the segment body 21 in the drum axis direction, and to the arm connecting member 34 of the moving mechanism 23, which is provided on the other side of the segment body 21 in the drum axis direction. 【0056】 The cylinder 50 is equipped with a piston rod 51 that moves axially by the intake and discharge of a fluid such as air. One end 50a of the cylinder 50 is rotatably connected to the plate portion 31. The tip 51a of the piston rod is rotatably connected to approximately the middle portion of the first arm 32. 【0057】 The cylinder 50 drives the first arm 32 to move the retaining member 22 between the housing position and the pressing position while maintaining the posture of the retaining member 22. 【0058】 Specifically, the retaining member 22 moves from the storage position to the pressing position as the cylinder 50 extends, keeping its inner surface 22b facing inward in the drum radial direction. The retaining member 22 also moves from the pressing position to the storage position as the cylinder 50 retracts, keeping its inner surface 22b facing inward in the drum radial direction. In other words, the first arm 32, which constitutes the parallel link mechanism, receives power from the cylinder 50 in one direction, causing the retaining member 22 to move between the pressing position and the storage position. 【0059】 Furthermore, the plate portion 31 is provided with a first stopper 35 and a second stopper 36. The first stopper 35 and the second stopper 36 are provided in the same position as the arm connecting member 34 in the drum axis direction. 【0060】 The first stopper 35 and the second stopper 36 are each equipped with a male threaded portion that screws into a female threaded portion provided on the plate portion 31, and a nut that screws into the male threaded portion, and the amount of protrusion outward from the plate portion 31 in the drum radial direction is adjustable. 【0061】 The first stopper 35 contacts the arm connecting member 34, which moves the pressing member 22 from the pressing position to the storage position, at a predetermined position, thereby restricting the movement of the arm connecting member 34. As a result, the first stopper 35 stops the pressing member 22 at the predetermined position in the recess 26 so that the outer surface 22a of the pressing member 22 becomes a continuous curved surface with the rubber member attachment surface 21a of the segment body 21. 【0062】 The second stopper 36 contacts the arm connecting member 34, which moves the pressing member 22 from the housing position to the pressing position, at a predetermined position, thereby restricting the movement of the arm connecting member 34. As a result, the second stopper 36 stops the pressing member 22 at a predetermined position such that the inner surface 22b of the pressing member 22 is positioned on the outer side in the drum radial direction of the rubber member attachment surface 21a of the segment body 21, with a gap corresponding to the thickness of the sheet-like rubber member S. 【0063】 (6) Control unit 60 As shown in Figure 8, the control unit 60 is connected to at least the detection unit 61, the operating device 62, the segment drive device 63, the drum rotating device 64, and the material supply device 65. The operating device 62, the segment drive device 63, and the drum rotating device 64 are part of the molding drum device 10. 【0064】 The detection unit 61 detects whether the sheet-like rubber member S is present at the position where the application of the sheet-like rubber member S to the rubber member application surface 21a begins, thereby detecting whether the front end Se of the sheet-like rubber member S is attached to a predetermined position on the rubber member application surface 21a. 【0065】 The operating device 62 is a device that changes the amount of fluid inside the cylinder 50 in order to extend and retract the piston rod 51 of the cylinder 50 provided on the moving mechanism 23 in the axial direction. The operating device 62 causes the cylinders 50 of the moving mechanism 23 on both sides in the axial direction of the drum to operate simultaneously. 【0066】 Furthermore, the drum rotating device 64 is a well-known device for rotating the molding drum device 10, and includes, for example, a motor. The material supply device 65 is a device for supplying the sheet-like rubber material S to the first rubber material attachment surface 21aa of the front end holding segment 20. 【0067】 (7) Operation of the molding drum device 10 Next, the operation of the molding drum device 10 will be described. 【0068】 The cylindrical rubber member is formed by wrapping a sheet-like rubber member S around the outer surface of the molding drum device 10. The length of the sheet-like rubber member S is approximately the same as the circumference of the molding drum device 10. Molding in the molding drum device 10 is performed under the control of the control unit 60. The molding process is as shown in Figure 9. 【0069】 First, a material supply device 65, which supplies the sheet-shaped rubber member S to the molding drum device 10, approaches the molding drum device 10. Then, the front end Se of the sheet-shaped rubber member S supplied from the material supply device 65 is attached to the first rubber member attachment surface 21aa of the segment body 21 (S1 in Figure 9, Figure 10). At this time, the retaining member 22 is positioned in its storage position. 【0070】 The sheet-like rubber member S adheres to the first rubber member attachment surface 21aa of the segment body 21 by its adhesive force. At this time, it is preferable that the front end Se of the sheet-like rubber member S is positioned between the pressing position where the pressing member 22 presses the sheet-like rubber member S and the recess 26 provided in the segment body 21. 【0071】 Next, the molding drum device 10 rotates by a predetermined angle, attaching the front end of the sheet-like rubber member S to at least a portion of the first rubber member attachment surface 21aa (S2 in Figure 9, Figure 4). 【0072】 Next, the moving mechanism 23 is activated, moving the pressing member 22 from the housing position to the pressing position, and the sheet-like rubber member S is sandwiched between the inner surface 22b of the pressing member 22 and the first rubber member attachment surface 21aa. As a result, the pressing member 22 holds the sheet-like rubber member S by pressing it at a position a predetermined length behind the front end Se of the sheet-like rubber member S (S3 in Figure 9, Figure 8). 【0073】 After the pressing member 22 presses and holds the sheet-like rubber member S, the detection unit 61 detects whether the front end Se of the sheet-like rubber member S is attached to a predetermined position on the first rubber member attachment surface 21aa (S4 in Figure 9). 【0074】 If the detection unit 61 does not detect that the front end Se of the sheet-like rubber member S is attached to the predetermined position on the first rubber member attachment surface 21aa (NO in S4 of Figure 9), the rotation of the molding drum device 10 is stopped, and the operator is notified that the sheet-like rubber member S has detached from the first rubber member attachment surface 21aa of the segment body 21, and the molding drum device 10 is stopped (S5 in Figure 9). 【0075】 On the other hand, if the detection unit 61 detects that the front end Se of the sheet-like rubber member S is attached to a predetermined position on the rubber member attachment surface 21a (YES in S4 of Figure 9), the molding drum device 10 rotates and wraps the sheet-like rubber member S around the molding drum device 10 (S6 in Figure 9). During the rotation of the molding drum device 10, the pressing member 22 and the first rubber member attachment surface 21aa continuously press against a position a predetermined length behind the front end Se of the sheet-like rubber member S. 【0076】 Then, when the molding drum device 10 has rotated nearly one full turn and the Se of the sheet-like rubber member S has reached a predetermined position (YES in S7 of Figure 9), the rotation of the molding drum device 10 stops (S8 in Figure 9). At this time, the sheet-like rubber member S is wrapped around almost the entire outer surface of the molding drum device 10, but it is not attached to the outside of the recess 26 provided in the segment body 21. For example, the sheet-like rubber member S is not attached to the second rubber member attachment surface 21ab and the outside of the recess 26 of the segment body 21. 【0077】 After the rotation of the molding drum device 10 stops, the moving mechanism 23 operates to move the pressing member 22 from the pressing position to the storage position. This releases the holding of the sheet-like rubber member S by the pressing member 22 (S9 in Figure 9). 【0078】 Then, after the retaining member 22 returns to its storage position, the molding drum device 10 rotates again. This rotation causes the sheet-like rubber member S to be attached to the second rubber member attachment surface 21ab of the segment body 21 and to the outer surface 22a of the retaining member 22 in its storage position (S10 in Figure 9). 【0079】 When the sheet-like rubber member S is wound up to the end (YES in S11 of Figure 9), the rear end of the sheet-like rubber member S is positioned to coincide with or overlap the front end Se, and is then joined to the front end Se of the sheet-like rubber member S. 【0080】 The molding of the cylindrical rubber member is completed when the sheet-shaped rubber member S is wound up to the end. The completed cylindrical rubber member is sent to a later process and used as part of a pneumatic tire. 【0081】 (8) Effects In the molding drum device 10 of this embodiment described above, the guide section 30 receives power from the piston rod in one direction to move the pressing member 22 between the housing position and the pressing position. Therefore, in this embodiment, the operating time can be shortened compared to the case in which power is applied in multiple directions to move the pressing member 22 between the housing position and the pressing position, and the time required to mold the sheet-like rubber member S into a cylindrical shape can be shortened. 【0082】 Furthermore, in this embodiment, a first stopper 35 is provided to restrict the movement of the arm connecting member 34 that moves the pressing member 22 from the pressing position to the storage position. Therefore, the position of the pressing member 22 when it is placed in the storage position can be finely adjusted so that the outer surface 22a of the pressing member 22 becomes a continuous curved surface with the rubber member attachment surface 21a of the segment body 21. 【0083】 Furthermore, in this embodiment, a second stopper 36 is provided to restrict the movement of the arm connecting member 34 that moves the pressing member 22 from the housing position to the pressing position. Therefore, the distance between the inner surface 22b of the pressing member 22 and the first rubber member attachment surface 21aa can be finely adjusted so that the sheet-like rubber member S can be held with appropriate pressure. 【0084】 Furthermore, in this embodiment, since the pressing member 22 presses a position away from the rear of the front end Se of the sheet-like rubber member S attached to the first rubber member attachment surface 21aa, the position of the front end Se of the sheet-like rubber member S can be detected from the outside in the radial direction of the drum using the detection unit 61, and the front end Se and the rear end of the sheet-like rubber member S can be joined with high precision. 【0085】 Furthermore, in this embodiment, since the arithmetic mean roughness Ra of the inner surface 22b of the pressing member 22 is greater than that of the first rubber member attachment surface 21aa, when the pressing member 22 is moved from the pressing position to the storage position, the sheet-like rubber member S is more likely to peel off from the inner surface 22b of the pressing member 22, and the sheet-like rubber member S is less likely to peel off from the first rubber member attachment surface 21aa. 【0086】 The embodiments of the present invention have been described above, but these embodiments are presented as examples only. It is not intended to limit the scope of the invention. These novel embodiments are a variety of other embodiments. It is possible to implement the invention in this form, and various omissions and substitutions are permitted without departing from the spirit of the invention. These embodiments and their variations are not included in the scope or gist of the invention. It is included within the scope of the invention described in the claims and its equivalents. In the above embodiment, a parallel link mechanism consisting of a plate portion 31, a first arm 32, and a second arm 33 was described as a guide portion 30 that receives power from the piston rod 51 of the cylinder 50 to move the retaining member 22 between the housing position and the pressing position. However, the guide portion 30 is not limited to a parallel link mechanism. For example, the guide portion may consist of a guide pin provided on the retaining member 22 and a guide groove that guides the guide pin so that the retaining member 22 moves between the housing position and the pressing position. [Explanation of Symbols] 【0087】 10... Molding drum device, 11... Segment, 11a... Outer surface, 13... Front end holding device, 14... Segment holding member, 20... Segment for front end holding, 21... Segment body, 21a... Rubber member attachment surface, 21aa... First rubber member attachment surface, 21ab... Second rubber member attachment surface, 22... Pressing member, 22a... Outer surface, 22b... Inner surface, 22c... Inclined surface, 23... Moving mechanism, 26... Recess, 26a... Inclined wall, 30... Side section, 31...Plate section, 32...First arm, 32a...One end, 32b...Other end, 33...Second arm, 33a...One end, 33b...Other end, 34...Arm connecting member, 35...First stopper, 36...Second stopper, 50...Cylinder, 51...Piston rod, 60...Control unit, 61...Detection unit, 62...Operating device, 63...Segment drive device, 64...Drum rotation device, 65...Metal supply device, S...Sheet-shaped rubber member

Claims

[Claim 1] A molding drum apparatus comprising a drum having multiple segments arranged in the circumferential direction of the drum, a sheet-like rubber member wrapped around the outer surface of the drum, and the front and rear ends of the sheet-like rubber member joined together to form a cylindrical rubber member on the outer surface of the drum, At least one of the multiple segments is a front end holding segment, The front end holding segment comprises a rubber member attachment surface that forms a part of the outer circumferential surface of the drum, a pressing member that presses the sheet-like rubber member against the rubber member attachment surface, a recess that is recessed inward in the radial direction of the drum from the rubber member attachment surface and accommodates the pressing member, and a moving mechanism that moves the pressing member between the recess and the outside of the sheet-like rubber member attached to the rubber member attachment surface. The aforementioned moving mechanism comprises a cylinder for moving a piston rod in the axial direction, and a guide portion connected to the piston rod and receiving power from the piston rod in one direction for moving the pressing member between the recess and the rubber member attachment surface, in a molding drum device. [Claim 2] The molding drum apparatus according to claim 1, wherein the guide portion comprises a parallel link mechanism. [Claim 3] The molding drum apparatus according to claim 2, further comprising a first stopper that restricts the movement of the parallel link mechanism that moves the pressing member from the rubber member attachment surface to the recess. [Claim 4] The molding drum apparatus according to claim 2, further comprising a second stopper for restricting the movement of the parallel link mechanism that moves the pressing member from the recess to the rubber member attachment surface. [Claim 5] The pressing member presses a position away from the front end of the sheet-like rubber member attached to the rubber member attachment surface, The molding drum apparatus according to claim 1, further comprising a detection unit for detecting the front end of the sheet-like rubber member while the pressing member is pressing the sheet-like rubber member. [Claim 6] The arithmetic mean roughness of the portion of the pressing member that comes into contact with the sheet-like rubber member is: The molding drum apparatus according to claim 1, wherein the arithmetic mean roughness of the portion of the front end holding segment facing the pressing member with the sheet-like rubber member in between is greater than the arithmetic mean roughness of the rubber member-attached surface of the front end holding segment.

Images