Abstract:
The present invention glues a rubber strip on the surface of a non-right circular cylindrical winding body with good precision. The present invention reduces the space occupied by the apparatus. The tire member-forming apparatus is provided with a transport conveyor with a conveyor belt that is guided by guide rollers so that the conveyor belt is able to circle. The conveyor surface of the conveyor belt is provided with a conveyor surface width center line that extends in a straight line over the entire length thereof. The guide rollers are grouped into guide rollers on the front side of the conveyor direction and guide rollers on the back side of the conveyor direction. The front guide rollers are held so as to be capable of tilting around the conveyor surface width center line. As a result, on the conveyor surface, a twistable twisting conveyor surface section is formed between a front conveyor surface section, which is supported by the front guide rollers, and a back conveyor surface section, which is supported by the back guide rollers.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a tire member-forming apparatus that sticks a rubber strip on a periphery of a non-straight cylindrical wound body with a high accuracy. 
       BACKGROUND ART 
       [0002]    As a method for forming a rubber member in pneumatic tires, there is known a strip-winding technique using an unvulcanized rubber strip. According to the technique, the rubber strip is continuously wound around a surface of the wound body as a tire former or the like in a tire circumferential direction to form an annular rubber member (for example, a tread rubber, a sidewall rubber, or the like). In the strip-winding technique, various cross-section shapes can be obtained by changing the winding pitch of the rubber strip or the number of times when the rubber strip is wound. 
         [0003]    Patent Literature 1 shown below proposes a rubber strip-forming apparatus (a) for use in the strip-winding technique as illustrated in  FIG. 9 . The forming apparatus (a) is configured to stick a rubber strip G with a high accuracy on the surface of a wound body (b) of a non-straight cylindrical shape such as a drum shape, for example. The forming apparatus (a) includes a rubber strip transport conveyor (c). 
         [0004]    Specifically, the forming apparatus (a) includes: 
         [0005]    (1) a lateral moving means (gx) that moves the transport conveyor (c) laterally along an X-axis direction parallel to an axis (bi) of the wound body (b); 
         [0006]    (2) a vertical moving means (gy) that moves the transport conveyor (c) forward or backward toward the wound body (b) along a Y-axis direction; and 
         [0007]    (3) a turning means (gz) that turns the transport conveyor (c) around an axis (Zi) in the vertical Z-axis direction. 
         [0008]    Accordingly, even when the wound body (b) has a non-straight cylindrical profile, a guide roller (e) positioned on the foremost side in the transport direction of the transport conveyor (c) can be freely inclined in accordance with the profile. This makes it possible to stick the rubber strip G with a high accuracy without causing wrinkles or large distortion such as uneven stretch. 
         [0009]    According to this structure, however, the long transport conveyor (c) entirely turns around the vertical axis (Zi). This requires a large space for the turning, which makes it difficult to install the forming apparatus adjacent to another forming apparatus. In addition, in the inside area of the turning radius, the work area for workers needs to be significantly limited due to a fear of collision with the transport conveyor©, which leads to a disadvantage in work efficiency. 
       CITATION LIST 
     Patent Literature 
       [0010]    Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2006-110856 
       SUMMARY OF INVENTION 
     Technical Problem 
       [0011]    An object of the present invention is to reduce an apparatus footprint to enable installation adjacent to another forming apparatus and increase the work area for workers. Another object of the present invention is to provide a tire member-forming apparatus that allows a rubber strip to be stuck with a high accuracy on the surface of a non-straight cylindrical wound body. 
       Solution to Problem 
       [0012]    The present invention provides a tire member-forming apparatus including a drum device including a wound body rotatably driven and having a non-straight cylindrical shape around which a rubber strip is wound, a rubber strip supply device to supply the rubber strip and a rubber strip sticking device including an applicator transporting the rubber strip supplied from the rubber strip supply device and winding the same around the wound body. The applicator includes a transport conveyor including a transport belt for transporting the rubber strip on a transport surface, the transport belt being guided by a plurality of guide rollers in a manner capable of circling. The transport surface includes a center line in a width direction extending linearly over the entire length of the transport surface. The guide rollers include front guide rollers including a foremost guide roller disposed on the foremost side of the transport direction and back guide rollers including a backmost guide roller disposed on the backmost side of the transport direction. The front guide rollers are held in a manner capable of tilting around the center line of the transport surface in the width direction so that the transport surface forms a twistable transport surface portion between a front transport surface portion supported by the front guide rollers and a back transport surface portion supported by the back guide rollers. 
         [0013]    In the tire member-forming apparatus according to the invention, it is preferable that the rubber strip supply device includes a rubber extruder including a gear pump capable of quantitatively extruding rubber and an extrusion head that pre-shapes the rubber extruded from the gear pump. 
         [0014]    In the tire member-forming apparatus according to the invention, it is preferable that the back guide rollers are supported by a first frame and the front guide rollers are supported by a second frame held at the first frame in a manner capable of tilting around the center line of the transport surface in the width direction. 
         [0015]    In the tire member-forming apparatus according to the invention, it is preferable that the applicator includes a press conveyor having a press belt guided by a plurality of upper guide rollers in a manner capable of circling and presses the rubber strip against the transport belt, and the press belt includes a press surface that is composed of a front press surface portion pressing the rubber strip against the front transport surface portion, a back press surface portion pressing the rubber strip against the back transport surface portion, and a twistable press surface portion pressing the rubber strip against the twistable transport surface portion. 
         [0016]    In the tire member-forming apparatus according to the invention, it is preferable that the rubber strip supply device has a lateral movement stage supported movably in a direction parallel to an axis of the wound body, and the applicator is attached to the lateral movement stage. 
       Advantageous Effects of Invention 
       [0017]    The tire member-forming apparatus according to the present invention includes the transport conveyor having the transport belt for transporting the rubber strip, and the transport surface of the transport belt has the center line in the width-direction extending linearly along its entire length. 
         [0018]    When the guide rollers supporting the transport belt in such a manner as to be capable of circling are classified, in a transport-direction, into the front guide rollers and the transport-direction back guide rollers, the front guide rollers are held in such a manner as to be capable of tilting around the center line of the transport surface. Accordingly, the transport surface can form the twistable transport surface portion between the front transport surface portion supported by the front guide rollers and the back transport surface portion supported by the back guide rollers. 
         [0019]    The thus configured transport conveyor can incline freely the foremost guide roller in accordance with the profile of the wound body by the tilting around the center line of the transport surface. Accordingly, the rubber strip can be stuck with a high accuracy without causing wrinkles, uneven stretch, or the like. In addition, the transport surface includes the center line of the transport surface extending linearly over its entire length. This makes it possible to transport the rubber strip stably with a high accuracy without causing a change in the length of the rubber strip, following the tilting of the transport-direction foremost guide roller. 
         [0020]    The transport conveyor does not turn around the vertical axis but tilts around the center line of the transport surface. This eliminates the need for a large turning space and reduces the footprint of the apparatus. Accordingly, the forming apparatus can be installed adjacent to another forming apparatus. In addition, it is possible to increase the work area while maintaining the safety of the workers, thereby contributing to improvement in the efficiency of the sticking work. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0021]      FIG. 1  is a side view of an embodiment of a tire member-forming apparatus of the present invention; 
           [0022]      FIG. 2  is an enlarged side view of an applicator; 
           [0023]      FIG. 3  is a side view of a transport conveyor; 
           [0024]      FIG. 4  is an exploded perspective view of the transport conveyor; 
           [0025]      FIG. 5  is a conceptual view of a transport surface; 
           [0026]      FIG. 6  is a side view of a press conveyor; 
           [0027]      FIGS. 7A to 7C  are illustrative diagrams describing the turning of the transport conveyor around a center line of the transport surface in a width-direction; 
           [0028]      FIG. 8  is an illustrative diagram describing the operation of a sticking device; and 
           [0029]      FIG. 9  is a perspective view of a conventional rubber strip sticking device. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0030]    An embodiment of the present invention will be described below in detail.  FIG. 1  is a side view of a tire member-forming apparatus T of the embodiment of the present invention. As illustrated in  FIG. 1 , the tire member-forming apparatus T (hereinafter, also referred to as “forming apparatus T”) includes a drum device  1 , a rubber strip supply device  2 , and a rubber strip sticking device  3 . An unvulcanized rubber strip G is wrapped around the drum device  1 . The rubber strip supply device  2  supplies the rubber strip G. The rubber strip sticking device  3  sticks the rubber strip G supplied from the rubber strip supply device  2  to the drum device  1 . 
         [0031]    The drum device  1  includes a rotationally driven wound body  1 A and a support means  1 B rotatably supporting the wound body  1 A. 
         [0032]    In this example, the wound body  1 A is a tire former, and the rubber strip G is wrapped around the wound body  1 A to form a rubber member as a tread rubber or the like, for example. The wound body  1 A includes a non-straight cylindrical profile such as a drum shape in accordance with the tire shape, for example. The rubber strip G may have a cord embedded therein. In this case, a tire band layer is formed. 
         [0033]    The rubber strip supply device  2  has a known structure. The rubber strip supply device  2  of the embodiment includes a rubber extruder  2 A with a screw and a roller head  2 B disposed on the discharge side of the rubber extruder  2 A. The rubber extruder  2 A includes a gear pump  2   a  capable of quantitatively extruding rubber and an extrusion head  2   b  that pre-shapes the rubber extruded from the gear pump  2   a . The rubber extruder  2 A operates intermittently in accordance with the forming cycle of the forming apparatus T to form the rubber strip G only at the time of need. The rubber strip G shaped by the rubber extruder  2 A is supplied at a relatively high-temperature and in a high-viscosity state to the wound body  1 A. Therefore, the high-rigidity tire member can be manufactured. 
         [0034]    The roller head  2 B has a pair of calendar rollers. The calendar rollers extrude the pre-shaped rubber kneaded by rotation of the screw and extruded from the extrusion head  2   b  of the rubber extruder  2 A and shapes the same into the rubber strip G. In the embodiment, a festoon is provided on the downstream side of the roller head  2 B to hold the rubber strip G in a U-shaped loose state. 
         [0035]    The rubber strip G for use in the forming apparatus T of the embodiment is a long belt-like tape body in which the cross section has a thickness of about 0.5 to 4.0 mm and a width of about 5 to 35 mm, for example. 
         [0036]    The rubber strip sticking device  3  (hereinafter, also called simply “sticking device  3 ”) includes an applicator  4  that transports the rubber strip G and winds the same around the wound body  1 A. In this example, the sticking device  3  includes a base stand  5 , a lifting stage  9  supported by the base stand  5  in a manner capable of vertical movement, and a lateral movement stage  6  supported by the lifting stage  9  in a manner capable of lateral movement. The applicator  4  is attached to the lateral movement stage  6 . The lifting stage  9  is supported via a lifting means  12  in a manner capable of vertical movement. In this example, the lifting means  12  includes a pair of vertical guide shafts  12   a  and a vertical ball screw shaft  12   b . The upper ends of the guide shafts  12   a  are fixed to the lifting stage  9  and the lower ends of the same are fixed to a lower plate  12   c . The ball screw shaft  12   b  is pivotally supported in a rotatable manner by the lifting stage  9  and the lower plate  12   c . The lower end portion of the ball screw shaft  12   b  is coupled to a lifting motor M 1  attached to the lower plate  12   c . The base stand  5  includes a support plate part  5   a  having guide holes into which the guide shafts  12   a  are inserted and a screw hole into which the ball screw shaft  12   b  is screwed. 
         [0037]    In this example, the lateral movement stage  6  is supported movably in an X-axis direction parallel to an axis  1   i  of the wound body  1 A via a lateral movement means  13 . As illustrated in  FIG. 2 , the lateral movement means  13  of this example includes guide rails  13   a  and a ball screw shaft  13   b  arranged on the lifting stage  9  in the X-axis direction. One end of the ball screw shaft  13   b  is coupled to a lateral movement motor (not illustrated) attached to the lifting stage  9 . The lateral movement stage  6  is provided with a guide portion guided by the guide rail  13   a  and a nut portion screwed into the ball screw shaft  13   b . Therefore, the applicator  4  can be freely changed in position in the vertical direction (Z-axis direction) and the lateral direction (X-axis direction) by driving of the lifting motor M 1  and the lateral movement motor. 
         [0038]    Next, the applicator  4  includes at least a transport conveyor  7  supported in a manner capable of moving integrally with the lateral movement stage  6 . In this example, the applicator  4  includes the transport conveyor  7  and a press conveyor  8  disposed above the transport conveyor  7 . 
         [0039]    The transport conveyor  7  includes a plurality of guide rollers  10  and a transport belt  11  guided by the guide rollers  10  in a manner capable of circling. As illustrated in  FIGS. 3 and 4 , the transport belt  11  has the upper surface as a transport surface  11 S. The rubber strip G on the transport surface  11 S is transported from a position P 1  of receiving from the rubber strip supply device  2  to a position P 2  of discharge toward the wound body  1 A. As conceptually illustrated in  FIG. 5 , the center line of the transport surface  11 S in a width-direction extends linearly over the entire length of the transport surface  11 S. That is, the transport surface  11 S includes the center line  11   j  of the transport surface extending linearly over its entire length. 
         [0040]    Next, as illustrated in  FIG. 3 , a plurality of guide rollers  10  is classified into front guide rollers  10 A including a foremost guide roller  10   a  disposed on the foremost side of the transport direction and back guide rollers  10 B including a backmost guide roller  10   b  disposed on the backmost side of the transport direction. The front guide rollers  10 A are held in a manner capable of tilting around the center line  11   j  of the transport surface in the width-direction. Accordingly, the transport surface  11 S has a front transport surface portion  11 SA, a back transport surface portion  11 SB, and a twistable transport surface portion  11 SM twistable around the center line  11   j  of the transport surface in the width-direction as illustrated in  FIG. 5 . The front transport surface portion  11 SA is supported by the front guide rollers  10 A. The back transport surface portion  11 SB is supported by the back guide rollers  10 B. The twistable transport surface portion  11 SM is formed between the front transport surface portion  11 SA and the back transport surface portion  11 SB. 
         [0041]    Specifically, the applicator  4  includes a first frame  15  that is fixed to the lateral movement stage  6  in a manner capable of moving integrally with the lateral movement stage  6  and a second frame  16  that is held by the first frame  15  in a manner capable of tilting around the center line  11   j  of the transport surface in the width-direction. 
         [0042]    The first frame  15  has a side plate-like base part  15 A that stands at one side edge of the lateral movement stage  6 . The base part  15 A extends backward beyond the back end of the lateral movement stage  6 . The back end side of the base part  15 A has an attachment plate part  15 B to which the second frame  16  is attached. The base part  15 A is attached horizontally, for example. The back guide rollers  10 B are pivotally supported by the base part  15 A. 
         [0043]    The second frame  16  has a support shaft  17  concentric with the center line  11   j  of the transport surface in the width-direction. The support shaft  17  is pivotally supported by a bearing holder  18  attached to the attachment plate part  15 B in a manner rotatable around the center line  11   j  of the transport surface in the width-direction. In addition, the second frame  16  of this example includes a back plate part  16 A fixed and attached to the support shaft  17  and a front plate part  16 B that bends from the upper end of the back plate part  16 A, for example, and extends forward. The front plate part  16 B has a side plate portion  16 B 1  parallel to the base part  15 A on the front end side. The front guide rollers  10 A are pivotally supported by the side plate portion  16 B 1 . 
         [0044]    The support shaft  17  is coupled to a drive motor (not illustrated) that is controllable in rotational angle such as a step motor, for example. A drive motor M 2  is coupled to the backmost guide roller  10   b . This allows the transport belt  11  to be driven and circled. 
         [0045]    A cutting means  19  is disposed on the second frame  16  to cut the rubber strip G on the front transport surface portion  11 SA. The cutting means  19  of this example includes a rotationally driven rotation shaft  19 A and a cutter blade  19 B that extends from the peripheral surface of the rotation shaft  19 A in a radially outward direction. The cutting means  19  can cut the rubber strip G while transporting the same, by the cutter blade  19 B making a single rotation at the same speed as the rubber strip G. A relatively large-diameter guide roller  10 A 1  is disposed under the cutter blade  19 B to support the transport belt  11  from beneath at the time of cutting. 
         [0046]    As illustrated in  FIG. 6 , the press conveyor  8  includes a plurality of upper guide rollers  20  and a press belt  21  guided by the upper guide rollers  20  in a manner capable of circling. The press belt  21  presses the rubber strip G against the transport belt  11 . This prevents the rubber strip G from being separated or shifted in position from the transport belt  11  or being slipped on the transport belt  11 . The press belt  21  has a press surface  21 S formed by a front press surface portion  21 SA, a back press surface portion  21 SB, and a twistable press surface portion  21 SM. The front press surface portion  21 SA presses the rubber strip G against the front transport surface portion  11 SA. The back press surface portion  21 SB presses the rubber strip G against the back transport surface portion  11 SB. The twistable press surface portion  21 SM presses the rubber strip G against the twistable transport surface portion  11 SM. 
         [0047]    Specifically, the upper guide rollers  20  are divided into front upper guide rollers  20 A and back upper guide rollers  20 B. The front upper guide rollers  20 A include a foremost upper guide roller  20   a  disposed on the foremost side of the transport direction. The back upper guide rollers  20 B include a backmost upper guide roller  20   b  disposed on the backmost side of the transport direction. The back upper guide rollers  20 B are pivotally supported by the base part  15 A of the first frame  15  as the back guide rollers  10 B. The front upper guide rollers  20 A are pivotally supported by the side plate part  16 B 1  of the second frame  16  as the front guide rollers  10 A. 
         [0048]    In this example, the press belt  21  is formed from a back press belt  21 B disposed on the back side of the cutting means  19  and a front press belt  21 A disposed on the front side of the cutting means  19 . 
         [0049]    In this example, the sticking device  3  includes a press-fit means  22  on the front side of the press conveyor  8 . The press-fit means  22  presses the rubber strip G stuck on the wound body  1 A against the wound body  1 A such that the rubber strip G is fitted to the wound body  1 A. The press-fit means  22  includes a pressure roller  22 B pivotally supported at the rod lower end of a cylinder  22 A via a holder. The cylinder  22 A is supported by the side plate part  16 B 1  of the second frame  16 . The pressure roller  22 B is pivotally attached in parallel to the front guide rollers  10 A. Therefore, the pressure roller  22 B is capable of tilting around the center line  11   j  of the transport surface in the width-direction, and inclines in accordance with the profile of the wound body  1 A to press-fit the rubber strip G. 
         [0050]    As illustrated in  FIG. 7A , the transport belt  11  of the transport conveyor  7  is preferably wider than the rubber strip G. The press belt  21  of the press conveyor  8  is preferably narrower than the rubber strip G. As illustrated in  FIGS. 7B and 7C , while the rubber strip G is pressed by the narrow press belt  21 , the turning angle θ around the center line  11   j  of the transport surface in the width-direction around which the belts  11  and  21  can turn without changing the lengths of the belts  11  and  21  is ±80 degrees. In this example, therefore, the turning angle θ ranges −80 to +80 degrees. 
         [0051]    As illustrated in  FIG. 3 , the applicator  4  of the embodiment is provided with a stopper  23  that suppresses dropping of the transport belt  11 . That is, the second frame  16  of the applicator  4  tilts around the center line  11   j  of the transport surface in the width-direction to provide the twistable transport surface portion  11 SM as described above. Accordingly, when the second frame  16  tilts such that the opening side of the guide rollers  10 A faces downward, the stopper  23  suppresses the dropping of the transport belt  11  off the guide rollers  10 A. The stopper  23  is preferably provided on the side plate part  16 B 1  of the second frame  16  to suppress the dropping of the transport belt  11  off the twistable transport surface portion  11 SM. The stopper  23  is more preferably provided to support the side plate part  16 B 1  on the back side beyond the back roller  10   c  out of the front guide rollers  10 A disposed on the backmost side of the transport direction. The stopper  23  may be configured to support only the transport belt  11 , for example, but is desirably configured to support both of the transport belt  11  and the press belt  21  as in the embodiment. 
         [0052]    In the embodiment, the stopper  23  has a cylindrical support piece  24  that extends in a direction orthogonal to the rotation axes of the guide rollers  10 . The support piece  24  is provided with cut slits  24   a  that guide the transport belt  11  or the press belt  21 . 
         [0053]    The sticking device  3  of this example supports the applicator  4  by the lifting stage  9  and the lateral movement stage  6  such that the applicator  4  can be changed in position in the vertical direction (Z-axis direction) and the lateral direction (X-axis direction). Accordingly, the sticking device  3  can cooperate with the turning operation around the center line  11   j  of the transport surface in the width-direction to stick the rubber strip G around the non-straight cylindrical wound body  1 A with a high accuracy in accordance with the profile of the wound body  1 A as illustrated in  FIG. 8 . Alternatively, instead of the lifting stage  9  and the lateral movement stage  6 , the wound body  1 A may be supported in a manner capable of moving in the vertical direction (Z-axis direction) and the lateral direction (X-axis direction) with respect to the applicator  4 . 
         [0054]    The particularly preferred embodiment of the present invention has been described in detail so far. However, the present invention is not limited to the illustrated embodiment but can be modified in various manners. 
       REFERENCE SIGNS LIST 
       [0000]    
       
         
           
               4  Applicator 
               7  Transport conveyor 
               10  Guide roller 
               10 A Front guide roller 
               10 B Back guide roller 
               11  Transport belt 
               11 S Transport surface 
               11   j  Center line of transport surface 
               11 SA Front transport surface portion 
               11 SB Back transport surface portion 
               11 SM Twistable transport surface portion