Patent Publication Number: US-11383425-B2

Title: Filament winding device

Description:
TECHNICAL FIELD 
     This disclosure relates to a filament winding device which winds a fiber bundle to a liner. 
     BACKGROUND 
     In Japanese Laid-Open Patent Publication No. 2013-78959, a filament winding device that winds carbon fiber bundles impregnated with resin to a mandrel has been disclosed. The filament winding device includes a mandrel supporting table that supports the mandrel to be rotatable and movable in an axial direction (horizontal direction) of the mandrel, and a helical winding device that winds fiber bundles to the mandrel helically. In the state in which tip portions of the fiber bundles are fixed to the mandrel, the mandrel supporting table rotates and moves the mandrel in the axial direction. As a result, the fiber bundles are pulled out from the helical winding device and helically wound to the mandrel at the predetermined winding angle. Because the fiber bundles are wound to the mandrel which is rotating and moving, a predetermined tension is applied to the fiber bundles. A carbon roll which is made by winding fiber bundles to a cylindrical mandrel has characteristics such as lightness, high-strength, and high rigidity. Therefore, the carbon roll is used in many fields. 
     We found that a carbon roll having higher rigidity than known ones is obtained by, for example, forming fiber bundle layers using pitch carbon fiber bundles having high elasticity, as described below. To be more specific, we formed the following layers: a 0-degree oriented layer in which fiber bundles are stuck onto the mandrel to be substantially parallel to the axial direction of a mandrel; a +θ-degree oriented layer in which fiber bundles are wound to be tilted to one side relative to the axial direction of the mandrel; and a −θ-degree oriented layer in which fiber bundles are wound to be tilted to the other side relative to the axial direction of the mandrel. The carbon roll made in this way has high natural frequency because of high rigidity, and even when the carbon roll rotates at high speed, vibration is less likely to occur. Therefore, the carbon roll may be preferably used as a high speed rotary member such as a winding roll of an industrial machine such as a film manufacturing machine or a printing machine, and a propeller shaft of an automobile. 
     In that regard, to form the 0-degree oriented layer by the filament winding device recited in JP &#39;959, the mandrel moves in the axial direction without rotating and, at the same time, the fiber bundles impregnated with resin need to be pulled out from a helical winding device and stuck onto the mandrel. However, when the mandrel is moved without being rotated, the fiber bundles are not wound to the mandrel. As a result, tension applied to the fiber bundles is low. On this account, the fiber bundle sags under its own weight, and the fiber bundle tends to be dislocated. In addition, sticking the fiber bundle onto target positions, e.g., a side portion or a bottom portion of the mandrel is difficult, with the result that forming the 0-degree oriented layer is difficult. 
     It could therefore be helpful to improve the stability of orientation of a fiber bundle when the fiber bundle is stuck onto the mandrel along the axial direction of the mandrel. 
     SUMMARY 
     Our filament winding device includes: a supporting unit that is able to support a mandrel on which fiber bundles impregnated with resin are wound and is able to move in an axical direction of the mandrel; and a helical unit including fiber bundle guide units disposed radially in a circumferential direction of the mandrel and guide the fiber bundles to the mandrel, respectively, the helical unit supplying the fiber bundles to the mandrel via the fiber bundle guide units, each of the fiber bundle guide units including at least one pressing roller which presses the fiber bundle supplied to the mandrel on a circumferential surface of the mandrel which is moving in the axial direction, and the at least one pressing roller being passively rotatable about a roller axis extending in a roller axial direction orthogonal to the axial direction, by making a contact with a circumferential surface of the mandrel. 
     As the fiber bundle is pressed on the circumferential surface of the mandrel by the pressing roller of the fiber bundle guide unit, the fiber bundle is stuck on the mandrel by the viscosity of resin. Because of this, even when the mandrel does not rotate and tension applied to the fiber bundle is low, the fiber bundle can be stuck on the mandrel before the fiber bundle supplied to the mandrel sags. As a result, the fiber bundle is easily stuck on a target position. Therefore, the fiber bundle is easily stuck to the mandrel along the axial direction of the mandrel. 
     In the filament winding device above, each of the fiber bundle guide units may further include a tension receiving member placed upstream of the at least one pressing roller in a fiber bundle running direction and receives tension of the fiber bundle not pressed on the mandrel yet. 
     Even when the fiber bundle is stuck on the mandrel without rotation of the mandrel, a certain degree of tension is applied to the fiber bundle supplied to the mandrel because the mandrel moves in the axial direction. Because the tension functions as to lift the pressing roller from the mandrel, pressing force of the pressing roller pressing the fiber bundle on the mandrel may be decreased, if the tension is directly applied the pressing roller. The tension applied to the fiber bundle is received by a tension receiving member placed upstream of the pressing roller. Because of this, the tension is suppressed from being directly applied to the pressing roller placed downstream of the tension receiving member so that the pressing force of the pressing roller is suppressed from becoming low. 
     In the filament winding device just above, the tension receiving member may be a roller. 
     For example, when the fiber bundle which is broken easily (such as a pitch carbon fiber bundle is equivalent to this) and stuck on the mandrel, the fiber bundle may be broken due to friction with the tension receiving roller when the tension receiving member is fixed. Because the fiber bundle runs smoothly along a roller, the fiber bundle is suppressed from being broken. 
     In the filament winding devices above, the helical unit further includes a guide movement mechanism that moves each of the fiber bundle guide units in a radial direction of the mandrel. 
     The positions of the fiber bundle guide units in the radial direction are adjusted in accordance with the outer diameter of the mandrel so that the fiber bundles are pressed on the circumferential surface of the mandrel with various diameters by the pressing roller. 
     The supporting unit may be able to reciprocate in the axial direction, and each of the fiber bundle guide units includes two or more pressing rollers, and as the two or more pressing rollers, a first pressing roller that presses the fiber bundle on the circumferential surface of the mandrel when the supporting unit moves toward one side in the axial direction and a second pressing roller placed on the other side than the first pressing roller in the axial direction and presses the fiber bundle on the circumferential surface of the mandrel when the supporting unit moves toward the other side in the axial direction are provided. 
     In a structure in which the supporting unit is able to reciprocate, the fiber bundle can be pressed on the circumferential surface of the mandrel by a first pressing roller when the mandrel moves toward one side in the axial direction, and pressed on the circumferential surface of the mandrel by a second pressing roller when the mandrel moves toward the other side. Because of this, the fiber bundle is stuck on the mandrel both when the mandrel moves forward and when the mandrel moves rearward. Therefore, the fiber bundle is efficiently stuck on the mandrel. 
     The mandrel may have a cylindrical shape extending in the axial direction, and the at least one pressing roller includes, in cross section including an axis of the at least one pressing roller, a reduced diameter part which is curved so that the diameter decreases toward the center in the roller axial direction. 
     For example, when the pressing roller is cylindrical in shape, the fiber bundle may not be stuck on the circumferential surface of the mandrel successfully because a contact area between the pressing roller and the mandrel having the curving circumferential surface is small. Because the reduced diameter part is facilitated to correspond to the circumferential surface of the mandrel, the contact area between the pressing roller and the mandrel circumferential surface is increased. Therefore, the fiber bundle is stably stuck on the circumferential surface of the mandrel. 
     In the filament winding device just above, in the at least one pressing roller, roller end parts may be formed at outer sides of the reduced part in the roller axial direction, respectively, and in the cross section of the at least one pressing roller, in a radial direction of the at least one pressing roller, the roller end parts are inside tangents to an outer edge of the reduced diameter part at ends in the roller axial direction, respectively, and an angle formed between each outer edge of the roller end parts and the outer edge of the reduced diameter part is an obtuse angle. 
     When the reduced diameter part is formed to reach the end in the roller axial direction, in the cross section of the pressing roller, an angle formed between an end face in the roller axial direction and the outer edge of the reduced diameter part is an acute angle (acute) so that described-below problems may happen. In the circumferential direction of the mandrel, when the fiber bundle has already been stuck on another position different from a position on which the fiber bundle is being stuck, the fiber bundle may be peeled off by the end portion of the pressing roller when the end portion of the pressing roller makes a contact with the fiber bundle on the another position described above. 
     The angle formed between each of the outer edges of the roller end parts and the outer edge of the reduced diameter part is an obtuse angle. In other words, the end portion and its surroundings of the reduced diameter part have a more gradual shape compared to when the reduced diameter part (part likely to make a contact with the fiber bundle) is formed to reach the end in the roller axial direction. Because of this, even when the end portion of the reduced diameter part in the roller axial direction contacts the fiber bundle that has already been stuck on the mandrel, the fiber bundle is less likely to be peeled off. 
     In the filament winding device just above, the roller end parts may be rectangular in cross section. 
     Because the roller end parts are rectangular in cross section (i.e., the roller end portion is cylindrical, and the diameter of the roller end portion is consistent), processing in manufacture can be easily done. 
     Each of the fiber bundle guide units may further include: a roller supporter supporting the at least one pressing roller to be rotatable; and a guide supporter to which the roller supporter is attached, and the roller supporter includes a cushioning member absorbing variation of pressing force of pressing the at least one pressing roller on the mandrel. 
     Even when the pressing force of the pressing roller is changed by some reasons such as small roughness on the circumferential surface of the mandrel or small vibration of the supporting unit, the variation of the pressing force is absorbed by the cushioning member. Therefore, the following problems can be suppressed: the fiber bundle is not stuck on the mandrel successfully because the pressing force is decreased too much; and pressure to, e.g., the pressing roller becomes excessive because the pressing force becomes excessive. 
     In the filament winding device just above, the roller supporter may include, as the cushioning member, a plate spring member supporting the at least one pressing roller to be rotatable. 
     The plate spring member can support the pressing roller and absorb the variation of the pressing force of the pressing roller at the same time. In other words, it is unnecessary to individually provide a member to support a pressing roller and a cushioning member. Therefore, an increase in the number of components and cost growth are suppressed. 
     The roller supporter may support the at least one pressing roller at both sides. 
     When the pressing roller is cantilevered, an end portion that is not supported tends to be displaced greatly compared to an end portion that is supported, in the roller axial direction. Therefore, the roller axis of the pressing roller tends to be tilted with respect to the circumferential surface of the mandrel, with the result that the fiber bundle may not be stably stuck on the mandrel. Because the pressing roller is supported at both sides, the one end portion of the pressing roller in the roller axial direction is suppressed from being displaced greatly compared to the other end portion. As a result, the pressing roller is suppressed from being tilted with respect to the circumferential surface of the mandrel. Therefore, the fiber bundle is stably stuck on the mandrel. 
     The winding device may further comprise a controller controlling the supporting unit and, after the controller moves the supporting unit to the one side in the axial direction to stick the fiber bundles to reach an end portion on the other side from an end portion of one side in the axial direction of the mandrel, the controller moves the supporting unit further to the one side in the axial direction so that a part of each of the fiber bundles supplied to the mandrel juts out from the end portion on the other side of the mandrel, and the controller moves the supporting unit back to the other side in the axial direction, in a state in which jut-out parts of the fiber bundles jutting out from the end portion of the mandrel are enclosed by an annular returning guide tool. 
     In a structure in which the supporting unit is able to reciprocate, it is preferable in consideration of the production efficiency that the fiber bundle stuck to reach the end of the mandrel is returned in the axial direction without being cut so that the fiber bundle is continuously stuck onto the mandrel. However, when the fiber bundle is stuck to reach the end portion of the mandrel and then the fiber bundle is returned by moving the mandrel in the opposite direction, the fiber bundle stuck onto the end portion of the mandrel may be pulled in the axial direction and peeled off by the tension applied to the fiber bundle. 
     The controller performs control such that, after the fiber bundle is stuck on the mandrel as the supporting unit is moved to one side in the axial direction, a part of each fiber bundle is arranged to jut out from the end portion on the other side of the mandrel. Subsequently, when the jut-out parts of the fiber bundles are enclosed by the annular returning guide tool, the supporting unit is moved back to the other side. As a result, the fiber bundles are returned to the other side while being guided outward from the inner side in the radial direction of the ring tool. The supporting unit moves further to the other side, with the result that the returning guide tool is pulled toward the mandrel by the tension of the fiber bundle. By using the returning guide tool with a proper size corresponding to the size of the mandrel, the returning guide tool which is pulled is received by the end face of the mandrel by making a contact therewith. Therefore, even when the returning fiber bundle is pulled in the axial direction, the fiber bundle is received by the returning guide tool. As a result, the fiber bundle is suppressed from being peeled off from the mandrel. As the supporting unit is further moved to the other side, the sticking of the fiber bundle can be continued. Therefore, the fiber bundle is continuously stuck on the mandrel by the reciprocal movement of the mandrel. 
     In the filament winding device just above, the returning guide tool may be separated into guide pieces in a circumferential direction of the returning guide tool. 
     For example, the fiber bundles can be enclosed by using a returning guide tool in which a narrow slit is formed from the outer side in the radial direction to the inner side and guiding the fiber bundles to the inner side in the radial direction of the tool, for example, by hand. However, in this configuration, when the fiber bundles are threaded into the slit, the fiber bundles may get damaged by making a contact with the slit of the returning guide tool. By connecting guide pieces and forming the returning guide tool, it is possible to enclose the fiber bundles from the outer side in the radial direction of the tool. In other words, because it is unnecessary to thread the fiber bundles into the slit to enclose the fiber bundles, damage to the fiber bundles is suppressed. 
     The returning guide tool may be ring-shaped. 
     For example, the fiber bundles can be enclosed by a returning guide tool that is polygonal in shape in the circumferential direction. However, when such a guide tool is used, the fiber bundles may get damaged by, e.g., hitting on a corner of the returning guide tool. Because the returning guide tool is ring-shaped (i.e., has a smooth shape on the whole), damage to the fiber bundles is suppressed. 
     The maximum outer diameter of the returning guide tool may be shorter than the outer diameter of the mandrel. 
     When the returning guide tool encloses the fiber bundles, the returning guide tool is suppressed from jutting outward compared to the mandrel in the radial direction. Therefore, when the supporting unit is returned to the other side, the returning guide tool is suppressed from interfering with, e.g., the pressing roller of the helical unit. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a filament winding device related to an example. 
         FIG. 2  is a perspective view of a winder. 
         FIG. 3  is a block diagram showing an electrical structure of the filament winding device. 
         FIG. 4  is a front view of an upper part of a helical winding unit. 
         FIG. 5  is a perspective view of a fiber bundle guide unit. 
         FIGS. 6A to 6C  are a front view, plan view, and side view of the fiber bundle guide unit, respectively. 
         FIG. 7  is a cross section of a pressing roller. 
         FIGS. 8A and 8B  show a guide movement mechanism. 
         FIG. 9  shows a mandrel which is supplied with a fiber bundle. 
         FIGS. 10A and 10B  show a contact state of the pressing roller and the mandrel. 
         FIG. 11  is a flow chart showing an process of sticking the fiber bundle onto the mandrel. 
         FIG. 12  is a flow chart showing a detailed process of sticking of the fiber bundle in a reciprocating manner. 
         FIGS. 13A to 13C  show a ring guide. 
         FIGS. 14A to 14D  show a return of the fiber bundles with the ring guide. 
         FIGS. 15A to 15C  show the return of the fiber bundles with the ring guide. 
         FIGS. 16A to 16C  show the return of the fiber bundle with the ring guide. 
         FIGS. 17A and 17B  show the ring guide related to a modification. 
         FIG. 18  shows a filament winding device related to another modification. 
     
    
    
     REFERENCE SIGNS LIST 
     
         
           1  filament winding device 
           5  controller (controller) 
           20  supporting unit 
           40  helical winding unit (helical unit) 
           50  fiber bundle guide unit 
           51  guide supporter 
           52  pressing roller supporter (roller supporting unit) 
           53  widening roller (tension receiving member) 
           54  pressing roller 
           54 F pressing roller (first pressing roller) 
           54 R pressing roller (second pressing roller) 
           55   a  reduced diameter part 
           55   b  roller end part 
           55   c  roller end part 
           55   d  outer edge 
           55   e  outer edge 
           71  plate spring member (cushioning member) 
           72  plate spring member (cushioning member) 
           80  guide movement mechanism 
           101  tangent 
           200  ring guide (returning guide tool) 
         C axis 
         F fiber bundle 
         Fa jut-out part 
         M mandrel 
       
    
     DETAILED DESCRIPTION 
     The following will describe an example with reference to  FIG. 1  to  FIG. 16C . Directions shown in  FIG. 1  are defined as a front-rear direction and a left-right direction, for convenience of explanation. Furthermore, a direction orthogonal to the front-rear direction and the left-right direction is defined as the up-down direction in which gravity acts. 
     Filament Winding Device 
     To begin, the following will describe a schematic structure of a filament winding device  1  with reference to  FIG. 1 . The filament winding device  1  includes a winder  2 , a creel stand  3 , and a control panel  4 . 
     The winder  2  winds fiber bundles F to a mandrel M. The fiber bundles F are, for example, made by impregnating fiber materials such as highly elastic carbon fibers termed pitch carbon fiber bundles with thermosetting synthetic resin. The pitch carbon fiber bundles are highly elastic but easily broken. The mandrel M is a core material for manufacturing, e.g., a propeller shaft of an automobile, and has a cylindrical shape. The details of the winder  2  will be given later. 
     The creel stand  3  supplies the fiber bundles F to a helical winding unit  40  (helical unit) described below. The creel stand  3  includes a supporting frame  11  and bobbin supporters  12  which are supported by the supporting frame  11 . The supporting frame  11  is roughly left-right symmetric, and at a central portion of the supporting frame  11  in the left-right direction, an installation space  13  where a part of the winder  2  is provided is formed (in this regard, the details of the installation space  13  are omitted). By the bobbin supporters  12 , bobbins B are supported to be rotatable, respectively. On the bobbins B, the fiber bundles F supplied to a helical winding unit  40  are wound. 
     The control panel  4  includes a controller  5 , a display  6 , and an operation unit  7 . The controller  5  controls an operation of each part of the winder  2 . The display  6  displays, e.g., a winding condition of the fiber bundle that is wound to the mandrel M by the winder  2 . The operation unit  7  inputs, e.g., the winding condition of the winder  2  in the controller  5  by an operator. 
     Winder 
     The structure of the winder  2  will be described with reference to  FIGS. 2 and 3 . The winder  2  includes a base  15 , supporting units  20  (first supporting unit  21  and second supporting unit  22 ), a hoop winding unit  30 , and the helical winding unit  40 . 
     The base  15  supports the supporting units  20 , the hoop winding unit  30 , and the helical winding unit  40 . The base  15  extends in the front-rear direction. On the base  15 , the first supporting unit  21 , the hoop winding unit  30 , the helical winding unit  40 , and the second supporting unit  22  are placed in this order from a front side in the front-rear direction. On a top surface of the base  15 , rails  16  are provided to extend in the front-rear direction. The supporting units  20  and the hoop winding unit  30  are placed on the rails  16  to be movable in the front-rear direction along the rails  16 . Meanwhile, the helical winding unit  40  is, at the front end portion of the installation space  13  of the creel stand  3 , fixed to the base  15  as shown in  FIG. 1 . 
     The supporting units  20  include the first supporting unit  21  placed in front of the hoop winding unit  30 , and the second supporting unit  22  placed behind the helical winding unit  40 . The supporting units  20  support the mandrel M to be rotatable about a supporting shaft  23  extending in the axial direction (front-rear direction) of the mandrel M. The supporting units  20  include a moving motor  24  that moves the supporting units  20  in the front-rear direction along the rail  16 , and a rotating motor  25  that rotates the mandrel M as shown in  FIG. 3 . The moving motor  24  and the rotating motor  25  are driven and controlled by the controller  5 . 
     The hoop winding unit  30  performs hoop-winding of the fiber bundles to the mandrel M (winding the fiber bundles in a direction roughly orthogonal to the axial direction of the mandrel M). The hoop winding unit  30  includes a main body  31  and a rotating member  32 . The main body  31  is placed on the rails  16 , and supports the rotating member  32  to be rotatable about an axis of the mandrel M. The rotating member  32  is a disc-shaped member. At a central portion in a radial direction of the rotating member  32 , a passing hole  34  through which the mandrel M can pass is formed. To the hoop winding unit  30 , bobbins  33  to each of which the fiber bundle is wound are attached. The bobbins  33  are placed at regular intervals in a circumferential direction of the rotating member  32 . 
     The hoop winding unit  30  includes, as shown in  FIG. 3 , a moving motor  35  that moves the hoop winding unit  30  in the front-rear direction along the rails  16 , and a rotating motor  36  that rotates the rotating member  32 . The moving motor  35  and the rotating motor  36  are driven and controlled by the controller  5 . The controller  5  rotates the rotating member  32  while reciprocating the hoop winding unit  30  along the rails  16  so that the mandrel M passes through the passing hole  34  relatively. Because of this, the bobbins  33  are revolved about the axis of the mandrel M, and the fiber bundles are pulled out from the bobbins  33 . The fiber bundles pulled out are simultaneously hoop-wound on the surface of the mandrel M. 
     The helical winding unit  40  winds the fiber bundles F helically to the mandrel M (winds the fiber bundles in a direction roughly parallel to the axial direction of the mandrel M), and is able to form a 0-degree oriented layer described below on the mandrel M. The helical winding unit  40  includes a main body  41 , guides  42 , nozzles  43 , and a tension applying device (not illustrated). The main body  41  is vertically placed on the base  15 . At a central portion of the main body  41  in the left-right direction, a circular passing hole  44  through which the mandrel M can pass in the front-rear direction is formed. Along a circumferential direction of the passing hole  44 , the guides  42  and the nozzles  43  (in this example, twelve guides and twelve nozzles) are placed. When normal helical winding is performed, the fiber bundles pulled out from the bobbins B placed at the creel stand  3  are guided to the nozzles  43  via the guides  42 . Each of the nozzles  43  extends along a radial direction of the mandrel M, and guides the fiber bundle F to the inner side from the outer side in the radial direction. Each of the nozzles  43  is extendable and contractible in the radial direction by a later-described guide movement mechanism  80  as shown in  FIG. 8 . 
     The helical winding unit  40  includes, as shown in  FIG. 3 , a guide moving motor  45  that extends and contacts the nozzles  43 . The guide moving motor  45  is driven and controlled by the controller  5 . The controller  5  extends and contracts the nozzles  43  in accordance with the outer shape of the mandrel M while reciprocating the supporting units  20  along the rails  16  so that the mandrel M passes through the passing hole  44 . As a result, the fiber bundles F pulled out from the nozzles  43  are simultaneously wound helically to the surface of the mandrel M. Because the fiber bundles F are wound to the mandrel M which is rotating and moving, a predetermined tension is applied to the fiber bundles F by the tension applying device (not illustrated). 
     To start winding of the fiber bundles to the mandrel M by the winder  2 , to begin with, for example, an operator fixes yarn ends of the fiber bundles to the mandrel M by, e.g., tapes. Alternatively, a device for automatically fixing the yarn ends of the fiber bundles may be used. After the yarn ends of the fiber bundles are fixed to the mandrel M, the controller  5  drives and controls the motors  24 ,  25 ,  35 ,  36 , and  45  as shown in  FIG. 3  so that, to the mandrel M supported by the supporting units  20 , the hoop-winding is performed by the hoop winding unit  30  and the helical winding is performed by the helical winding unit  40 . As a result, a carbon roll in which the fiber bundles are wound to the mandrel M is made. The carbon roll has characteristics such as lightness and high rigidity. 
     We found that a carbon roll having higher rigidity than known ones is obtained by forming layers of fiber bundles F, for example, by using the above-described pitch carbon fiber bundles, as described below. To be more specific, we formed the following layers: a 0-degree oriented layer in which fiber bundles F are stuck onto a mandrel M to be substantially parallel to the axial direction of the mandrel M; a +θ-degree oriented layer in which the fiber bundles F are wound to be tilted to one side relative to the axial direction of the mandrel M; and a −θ-degree oriented layer in which the fiber bundles F are wound to be tilted to the other side relative to the axial direction of the mandrel M. 
     To form the 0-degree oriented layer, it is necessary to pull the fiber bundles F out from the helical winding unit  40  and stick them onto the mandrel M while moving the mandrel M in the front-rear direction without rotating the same. However, when the mandrel M is moved without being rotated, the tension applied to the fiber bundles F is low as compared to when the normal helical winding described above is performed (i.e., when the fiber bundles F are wound to the mandrel M while the mandrel M is rotating and moving). Therefore, the fiber bundle F may easily sag under its own weight, and sticking the fiber bundle onto the target positions, e.g., the side portion or the bottom portion of the mandrel may be difficult. The helical winding unit  40  includes a structure described below to facilitate sticking of the fiber bundles F onto the mandrel M along the front-rear direction. 
     0-Degree Oriented Layer 
     A structure that facilitates formation of the 0-degree oriented layer will be described with reference to  FIGS. 4 to 8B .  FIG. 4  is a front view of an upper part of a helical winding unit  40 .  FIG. 5  is a perspective view of a later-described fiber bundle guide unit  50 .  FIGS. 6A to 6C  are a front view, plan view, and side view of the fiber bundle guide unit  50 .  FIG. 7  is a cross section of a pressing roller  54 . The cross section includes an axis C.  FIG. 8A  is a cross section taken along a line VIII-VIII in  FIG. 4 .  FIG. 8B  shows a state in which the pressing roller  54  described below is in contact with the mandrel M. 
     As shown in  FIG. 4 , on the front surface of the helical winding unit  40 , plural fiber bundle guide units  50  (twelve units in this example) are provided to correspond to the nozzles  43  that are radially disposed. The fiber bundle guide units  50  guide the fiber bundles F to the mandrel M which is moving in the front-rear direction without rotating, and stick the fiber bundles F onto the mandrel M. The fiber bundle guide units  50  are detachable from the helical winding unit  40 , and attached to the helical winding unit  40  when a 0-degree oriented layer is formed on the mandrel M. The fiber bundle guide units  50  are placed radially in the circumferential direction of the passing hole  44  (i.e., the circumferential direction of the mandrel M). The fiber bundle guide units  50  are fixed to the nozzles  43  through connecting members  83  as shown in  FIGS. 8A and 8B  and described below, respectively. Because of this, the fiber bundle guide units  50  are movable in the radial direction of the mandrel M. 
     Fiber Bundle Guide Unit 
     The structure of the fiber bundle guide unit  50  will be described with reference to  FIGS. 5 to 7 . The fiber bundle guide unit  50  in  FIGS. 5 and 6A to 6C  is a fiber bundle guide unit  50  placed at a position of twelve o&#39;clock in  FIG. 4 . The up-down direction in  FIGS. 5 and 6A to 6C  is equivalent to the radial direction of the mandrel M. The left-right direction in  FIGS. 5 and 6A to 6C  is equivalent to an axial direction of a pressing roller  54  described below (hereinafter, this axial direction of the pressing roller  54  will be referred to as a roller axial direction). 
     As shown in  FIGS. 5 and 6A to 6C , the fiber bundle guide unit  50  includes a guide supporter  51 , a pressing roller supporter  52 , a widening roller  53 , and the pressing roller  54 . The fiber bundle guide unit  50  guides the fiber bundle F to the inner side from the outer side in the radial direction of the mandrel M (to the lower side from the upper side in  FIGS. 5 and 6A to 6C ) by the guide supporter  51 , and widens the fiber bundle F by the widening roller  53 . Furthermore, the fiber bundle guide unit  50  presses the fiber bundle F on the mandrel M by the pressing roller  54  supported by the pressing roller supporter  52 . The fiber bundle guide unit  50  includes two pressing roller supporters  52 , two widening rollers  53 , and two pressing rollers  54 . The two pressing roller supporters  52 , the two widening rollers  53 , and the two pressing roller  54  are symmetrical in the front-rear direction. Hereinafter, if required, reference symbols of front members such as the front pressing roller supporter  52  end with “F,” whereas reference symbols of rear members such as the rear pressing roller supporter  52  end with “R.” 
     To begin, the guide supporter  51  will be described. The guide supporter  51  guides the fiber bundle F to the inner side from the outer side in the radial direction of the mandrel M (i.e., to the downstream from the upstream in a fiber bundle running direction). The guide supporter  51  includes an upper member  61 , intermediate members  62  and  63 , and lower members  64  and  65 . In the guide supporter  51 , the upper member  61 , the intermediate members  62  and  63 , and the lower members  64  and  65  are placed in this order from the outer side to the inner side in the radial direction of the mandrel M. The guide supporter  51  has a shape which extends in the radial direction of the mandrel M on the whole. 
     The upper member  61  is connected to the helical winding unit  40  to be movable (details will be given later), and the intermediate members  62  and  63  are connected to end portions of the upper member  61  in the roller axial direction. The upper member  61  extends in the left-right direction (roller axial direction), and is roughly U-shaped when viewed from above as shown in  FIGS. 5 and 6B . The intermediate members  62  and  63  are members which have shapes as shown in  FIGS. 5, 6A and 6C  extending in the up-down direction (radial direction of the mandrel M). An upper portion of the intermediate member  62  is fixed to a left end portion of the upper member  61 , and an upper portion of the intermediate member  63  is fixed to a right end portion of the upper member  61 , respectively. Intermediate portions of the intermediate members  62  and  63  in the up-down direction are bent in the left-right direction as shown in  FIGS. 5 and 6A . Because of this, the intermediate members  62  and  63  function as plate springs and, for example, suppress small vibrations and the like of the fiber bundle guide unit  50  when the fiber bundle F is being stuck. 
     The lower members  64  and  65  support the two widening rollers  53  to be rotatable. The lower members  64  and  65  extend in the front-rear direction and each of these members has a substantially U-shape when viewed from above as shown in  FIG. 6B . The lower member  64  is fixed to a lower portion of the intermediate member  62 , and the lower member  65  is fixed to a lower portion of the intermediate member  63 , respectively. The lower members  64  and  65  support both ends of the two widening rollers  53  aligned in the front-rear direction to be rotatable as shown in  FIGS. 5 and 6C . To the lower member  64 , a guide rod  66  (hatched part in  FIG. 6B ) extending in the front-rear direction is attached. Similarly, to the lower member  65 , a guide rod  67  is attached. The guide rods  66  and  67  are aligned in the roller axial direction, and the fiber bundle F is introduced between the guide rods  66  and  67 . Because of this, the fiber bundle F guided by the guide supporter  51  is suppressed from deviating in the roller axial direction. 
     The widening roller  53  will be described. The two widening rollers  53  (tension receiving members) widen the fiber bundle F guided to the inner side from the outer side in the radial direction of the mandrel M, and receive the tension of the fiber bundle F. The two widening rollers  53  are, for example, cylindrical rollers made of resin. The two widening rollers  53  are supported at both sides to be rotatable by the lower members  64  and  65 , and passively rotate when the running fiber bundle F contacts the two widening rollers  53 . The axial direction of the widening roller  53  is orthogonal to the axial direction of the mandrel M. The widening roller  53 F is supported by front parts of the lower members  64  and  65 , and the widening roller  53 R is supported by rear parts of the lower members  64  and  65 , respectively as shown in  FIGS. 5 and 6C . 
     The widening rollers  53 F and  53 R are apart from each other in the front-rear direction, and the fiber bundle F is introduced between the widening rollers  53 F and  53 R. The widening roller  53 F is placed to contact the fiber bundle F when the mandrel M moves forward. The widening roller  53 R is placed to contact the fiber bundle F when the mandrel M moves rearward. The two widening rollers  53  are placed above (outer side in the radial direction of the mandrel M) the two pressing rollers  54  (as shown in  FIGS. 6A to 6C ), and configured not to contact the mandrel M. 
     The pressing roller supporter  52  will be described. As shown in  FIGS. 5 and 6A to 6C , the two pressing roller supporters  52  are attached to front and rear end portions of the guide supporter  51  one by one. To be more specific, the two pressing roller supporters  52  are attached to front and rear end portions of the lower members  64  and  65 . 
     The two pressing roller supporters  52  include plate spring members  71  and  72  (cushioning members), respectively. The plate spring members  71  and  72  are roughly L-shaped members when viewed in the front-rear direction. The plate spring member  71 F provided at the front pressing roller supporter  52 F is attached to a front end portion of the lower member  64  and extends forward. A front part of the plate spring member  71 F extends downward (inward in the radial direction of the mandrel M), and supports one end portion of a rotational shaft of the pressing roller  54 F. Similarly, the plate spring member  72 F is attached to a front end portion of the lower member  65 , and supports the other end portion of the rotational shaft of the pressing roller  54 F. In other words, by the plate spring members  71 F and  72 F, the pressing roller  54 F is supported at both sides to be rotatable. Even when pressing force of the pressing roller  54 F is changed by some factors such as a small roughness on the circumferential surface of the mandrel M, the variation of the pressing force is absorbed by the plate spring members  71 F and  72 F. 
     Likewise, the rear pressing roller supporter  52 R includes plate spring members  71 R and  72 R. The plate spring members  71 R and  72 R support both sides of the pressing roller  54 R to be rotatable, and absorb variation of the pressing force of the pressing roller  54 R on the mandrel M. 
     The two pressing rollers  54  will be described with reference to  FIGS. 5 to 7 . The two pressing rollers  54  stick the fiber bundle F onto the mandrel M along the front-rear direction (axial direction of the mandrel M) by pressing the fiber bundle F onto the mandrel M. Circumferential surfaces of the two pressing rollers  54  are made of a material having flexibility and/or elasticity such as, e.g., rubber or urethane. Axial directions of the two pressing rollers  54  are orthogonal to the axial direction of the mandrel M as shown in  FIG. 4 . As shown in  FIGS. 5 and 6A to 6C , the front pressing roller  54 F (first pressing roller) is supported at both sides to be rotatable by the pressing roller supporter  52 F, and the rear pressing roller  54 R (second pressing roller) is supported at both sides to be rotatable by the pressing roller supporter  52 R, respectively. The two pressing rollers  54 F and  54 R are passively rotated when the running filament F contacts the two pressing rollers  54 F and  54 R. The pressing roller  54 F is placed to press the fiber bundle F on the mandrel M when the mandrel M moves forward (one side). The pressing roller  54 R is placed to press the fiber bundle F on the mandrel M when the mandrel M moves rearward (the other side). 
     The shape of the cross section including the axis C of the pressing roller  54  will be described with reference to  FIG. 7 . The pressing roller  54  includes a roller main body  55  and a rotational shaft  56 . The roller main body  55  includes a reduced diameter part  55   a , a roller end part  55   b , and a roller end part  55   c . In an axial direction (roller axial direction) of the rotational shaft  56  which is a rotational axis of the pressing roller  54 , the reduced diameter part  55   a  is equivalent to a part between two chain double-dashed lines, and the roller end parts  55   b  and  55   c  are equivalent to parts formed at both outer sides of the reduced diameter part  55   a  in the roller axial direction. 
     The reduced diameter part  55   a  is curved so that the diameter decreases toward the center in the roller axial direction. In other words, the reduced diameter part  55   a  has a shape easily accompanying for the circumferential surface of the mandrel M. A cross section of the roller end part  55   b  is rectangular. In other words, the roller end part  55   b  has a cylindrical shape. The roller end part  55   c  has a shape and size similar to those of the roller end part  55   b.    
     An angle formed between an outer edge  55   d  of the reduced diameter part  55   a  in the cross section and an outer edge  55   e  of the roller end part  55   b  shown in  FIG. 7  will be described. The angle between the outer edge  55   d  and the outer edge  55   e , i.e., the angle θ between a tangent  101  to the end (point  100 ) of the outer edge  55   d  in the roller axial direction and the outer edge  55   e  is larger than 90° (i.e., an obtuse angle). An angle between the outer edge  55   d  and the outer edge of the roller end portion  55   c  is similarly arranged. As shown in  FIG. 7 , the roller end part  55   b  is placed more on the inner side than the tangent  101  in a radial direction of the pressing roller  54 . The roller end part  55   c  is similarly arranged. 
     Guide Movement Mechanism 
     The guide movement mechanism  80  moving the fiber bundle guide unit  50  structured as described above in the radial direction of the mandrel M will be described with reference to  FIGS. 8A and 8B .  FIG. 8A  is a cross section taken along a line VIII-VIII in  FIG. 4 .  FIG. 8B  shows a state in which the fiber bundle guide unit  50  has moved to the inner side in the radial direction of the mandrel M from the state shown in  FIG. 8A . 
     As shown in  FIGS. 8A and 8B , the guide movement mechanism  80  is attached to the main body  41  of the helical winding unit  40 . The guide movement mechanism  80  includes, for example, a spiral shaft  81 , a ball nut  82 , a connecting member  83 , the nozzle  43 , and the guide moving motor  45 . In the guide movement mechanism  80 , the ball nut  82  and the nozzle  43  attached to the ball nut  82  move in the radial direction of the mandrel M by the rotation of the spiral shaft  81 . In addition to that, the fiber bundle guide unit  50  is attached to the connecting member  83  attached to a tip portion of the nozzle  43 , and the fiber bundle guide unit  50  moves together with the nozzle  43 . The following describes details. 
     The spiral shaft  81  is supported to be rotatable by a supporting member  84  which is C-shaped and attached to a rear surface of a front end portion  41   a  of the main body  41 . The spiral shaft  81  extends in the radial direction of the mandrel M. The spiral shaft  81  has a male screw thereon. The spiral shaft  81  is driven and rotated by the guide moving motor  45  (indicated by an arrow  102 ). At a front part of the ball nut  82 , a female screw is formed. The ball nut  82  is screwed to the spiral shaft  81 . To a rear part of the ball nut  82 , the nozzle  43  is attached. The nozzle  43  is movable together with the ball nut  82  (indicated by an arrow  103 ). The L-shaped connecting member  83  is attached to an outer side end portion of the nozzle  43  in the radial direction of the mandrel M. The connecting member  83  extends forward from a part connected to the nozzle  43 , and a front end portion of the connecting member  83  extends inward in the radial direction of the mandrel M. The guide supporter  51  of the fiber bundle guide unit  50  is attached to the connecting member  83 . To be more specific, the upper member  61  of the guide supporter  51  is fixed to an inner side end portion in the radial direction of the front end portion of the connecting member  83 . By the guide movement mechanism  80  having the structure described above, the fiber bundle guide unit  50  is movable in the radial direction of the mandrel M (indicated by an arrow  104 ). The guide movement mechanism  80  adjusts a position of the fiber bundle guide unit  50  so that the pressing roller  54  contacts the circumferential surface of the mandrel M as shown in  FIG. 8B . 
     Supply Passage of Fiber Bundle 
     A supply passage of the fiber bundle F to the mandrel M will be described. When the 0-degree oriented layer is formed, after the fiber bundle F is guided by the guide  42 , as shown in  FIG. 4 , of the helical winding unit  40 , the fiber bundle F is guided to the inner side from the outer side in the radial direction of the mandrel M by the guide supporter  51  of the fiber bundle guide unit  50  as shown in  FIG. 8B , without passing through the nozzle  43 . Subsequently, the fiber bundle F is widened and guided due to contact with the widening roller  53  (the widening roller  53 F in  FIG. 8B ), and pressed on the mandrel M by the pressing roller  54  (the pressing roller  54 F in  FIG. 8B ). In this way, the fiber bundle F is supplied to the mandrel M by the helical winding unit  40  via the fiber bundle guide unit  50 . 
     Sticking 
     The following will describe an operation when the 0-degree oriented layer is formed (i.e., sticking that sticks the fiber bundle F onto the mandrel M in the front-rear direction) in the filament winding device  1  having the structure described above, with reference to  FIGS. 9, 10A  and  10 B.  FIG. 9  shows a state in which the fiber bundle F is supplied to the mandrel M and stuck onto the mandrel M.  FIG. 10A  shows a contact state of the pressing roller and the mandrel M when the pressing roller of the fiber bundle guide unit  50  has a different shape from the pressing roller  54  of this example.  FIG. 10B  shows a contact state of the pressing roller  54  and the mandrel M. In this regard, among the fiber bundle guide units  50 , the fiber bundle F which is supplied through the fiber bundle guide unit  50  placed at the twelve o&#39;clock position in  FIG. 4  will be described. However, the other fiber bundles F are similarly arranged. 
     To start sticking, to begin with, an operator guides the fiber bundle F to the mandrel M from the bobbin B through the fiber bundle guide unit  50 , and then fixes the tip portion of the fiber bundle F to the end portion (for example, the front end portion as shown in  FIG. 9 ) of the mandrel M by, e.g., a tape. Subsequently, the controller  5  (see  FIG. 3 ; controller) controls the guide moving motor  45  as shown in  FIG. 3  and activates the guide movement mechanism  80  as shown in  FIG. 8 . In addition, the controller  5  moves the fiber bundle guide unit  50  inward in the radial direction of the mandrel M, and causes the pressing roller  54  to contact the mandrel M. With this, the pressing roller  54  is pressed on the circumferential surface of the mandrel M, and a part of the fiber bundle F sandwiched between the pressing roller  54  and the mandrel M is pressed on the mandrel M. 
     Subsequently, the controller  5  controls the moving motor  24  as shown in  FIG. 3  and moves the supporting units  20  forward to move the mandrel M forward relative to the helical winding unit  40  as shown in  FIG. 9 . With this, the fiber bundle F runs with being pulled out from the bobbin B, and after being widened by the widening roller  53 F, the fiber bundle F is pressed on the mandrel M by the pressing roller  54 F to be stuck onto the mandrel M by the viscosity of the resin. Therefore, the fiber bundle F is likely to be stuck onto the mandrel M before sagging under its own weight. In this regard, when sticking is performed in this examples, the controller  5  does not drive the rotating motor  25  as shown in  FIG. 3 . In other words, when sticking is performed, the mandrel M does not rotate. 
     In this stage, even when the mandrel M does not rotate, some tension is applied to the fiber bundle F on account of the movement of the mandrel M in the axial direction. The tension functions as to lift the pressing roller  54 F. However, because the tension is received by the widening roller  53 F, the tension is suppressed from being directly applied to the pressing roller  54 F placed downstream of the widening roller  53 F in the fiber bundle running direction. 
     Furthermore, the controller  5  drives the moving motor  24  and moves the supporting units  20  forward so that the sticking of the fiber bundle reaches a rear end portion of the mandrel M. In this stage, sticking has been completed once. To the contrary, when the fiber bundle F is stuck from the rear end portion to the front end portion of the mandrel M, the fiber bundle F is guided by the widening roller  53 R and the pressing roller  54 R which are placed at a rear part of the fiber bundle guide unit  50 . 
     For example, as shown in  FIGS. 10A and 10B , when the fiber bundle F 1  is stuck along the axial direction of the mandrel M, a fiber bundle F 2  may already be stuck onto another position different from a position onto which the fiber bundle F 1  is stuck, along the axial direction of the mandrel M. In this example, as shown in  FIG. 10A , when the pressing roller is a pressing roller  154  which is entirely curved including both end portions (i.e., a reduced diameter part  155   a  is formed at the both end portions) in the axial direction, an angle θa between an end face of the pressing roller  154  and an outer edge of the reduced diameter part  155   a  is an acute angle. Therefore, the fiber bundle F 2  may be turned up by the pressing roller  154  when the mandrel M moves in the axial direction. In this regard, in the pressing roller  54  of this example, the angle θ between the outer edge  55   e  of the roller end part  55   b  and the outer edge  55   d  of the reduced diameter part  55   a  is an obtuse angle as shown in  FIG. 7 . The roller end part  55   c  is similarly arranged. In other words, as shown in  FIG. 10B , the end portion of the reduced diameter part  55   a  and its surroundings have a more gradual shape compared to the configuration shown in  FIG. 10A . Because of this, the fiber bundle F 2  is less likely to be turned up even if the end portion of the reduced diameter part  55   a  in the roller axial direction makes a contact with the fiber bundle F 2 . 
     Formation of 0-Degree Oriented Layer 
     The following will describe a specific process of forming the 0-degree oriented layer on the whole circumference of the mandrel M along the axial direction of the mandrel M with reference to  FIGS. 11 to 16C .  FIG. 11  is a flow chart showing a process of forming the 0-degree oriented layer by sticking the fiber bundles F onto the mandrel M.  FIG. 12  is a flow chart showing a specific process of sticking the fiber bundles F in a reciprocating manner (sequence S 102  described below). The other figures will be described according to need. 
     In this example, the fiber bundles F are stuck onto the whole circumference of the mandrel M by twelve fiber bundle guide units  50 , with the result that each fiber bundle F supplied by one bobbin B is stuck onto one-twelfth of the circumference of the mandrel M. Therefore, depending on the outer diameter of the mandrel M, after the sticking has been completed once as described above, the mandrel M needs to be rotated and moved in the circumferential direction by the width of the fiber bundle F to repeat sticking the fiber bundle F onto a part onto which the fiber bundle F is not stuck yet. For production efficiency, preferably, the fiber bundle F stuck to reach the end of the mandrel M is returned in the axial direction without being cut so that the fiber bundle F is continuously stuck onto the mandrel. However, when the fiber bundle F is stuck to reach a rear end portion of the mandrel M and then the fiber bundle F is returned by moving the mandrel M rearward, the fiber bundle F stuck onto the end portion of the mandrel M may be pulled in the axial direction and peeled off by the tension applied to the fiber bundle F. Therefore, in this example, the 0-degree oriented layer is formed by the way described below. 
     A procedure of forming the 0-degree oriented layer will be schematically described. To begin with, as described above, the tip portion of the fiber bundle F is fixed on the end portion of the mandrel M (S 101 ). Subsequently, the sticking, rotating of the mandrel M, and returning (details described below) in which the fiber bundle F is returned to the other side from one side in the axial direction of the mandrel M are repeated so that the fiber bundle F is stuck onto the mandrel M in the reciprocating manner (S 102 ). Finally, the both end portions, in the axial direction of the mandrel M, of the fiber bundle F stuck onto the whole circumference of the mandrel M are fixed by, e.g., performing the hoop-winding by the hoop winding unit  30  (S 103 ). 
     Process of Sticking the Fiber Bundle in Reciprocating Manner 
     The following will describe the details of the process of sticking the fiber bundle F onto the mandrel M in the reciprocating manner (S 102 ). 
     Before the description of the detailed process, a structure of a ring guide  200  (returning guide tool) used to cause the fiber bundle F to be returned in the axial direction will be described with reference to  FIGS. 13A to 13C .  FIG. 13A  is a whole figure of the ring guide  200 .  FIG. 13B  is an exploded view of the ring guide  200 .  FIG. 13C  shows that  FIG. 13B  is viewed from the direction indicated by the arrow XIII(c). 
     The ring guide  200  is a tool that encloses the fiber bundles F as shown in  FIGS. 13A to 13C  to return the fiber bundles F in the axial direction. The ring guide  200  has, as shown in  FIG. 13A , a ring shape that is circular in cross section. The outer diameter of the ring guide  200  is substantially identical to the outer diameter of the mandrel M as shown in  FIG. 13C . As shown in  FIG. 13B , the ring guide  200  can be separated into two guide pieces  201  and  202  each of which is half-ring shaped. The guide pieces  201  and  202  are, for example, connected by the way described below. As shown in  FIGS. 13B and 13C , an engagement hole  201   a  is formed at one end portion of the guide piece  201 , and an engagement pawl  201   b  is formed at the other end portion of the guide piece  201 . An engagement hole  202   a  is formed at an end portion of the guide piece  202  facing to the engagement pawl  201   b , and an engagement pawl  202   b  is formed at an end portion of the guide piece  202  facing to the engagement hole  201   a  as shown in  FIG. 13B . The engagement hole  201   a  and the engagement pawl  202   b  are engaged with each other and the engagement hole  202   a  and the engagement pawl  201   b  are engaged with each other so that the guide piece  201  and the guide piece  202  are connected to each other. 
     The following will describe a specific process of sticking the fiber bundle F onto the mandrel M in the reciprocating manner with reference to  FIG. 14A  to  FIG. 16C .  FIGS. 14A to 14D  and  FIGS. 15A to 15C  show the movements of the mandrel M and the fiber bundles F when the helical winding unit  40  and the mandrel M are viewed from the side.  FIGS. 16A to 16C  show the helical winding unit  40  and the mandrel M from above.  FIGS. 14A to 14D  and  FIGS. 15A to 15C  show the fiber bundle guide units  50  and the fiber bundles F at the twelve o&#39;clock position and six o&#39;clock position in  FIG. 4 .  FIGS. 16A to 16C  shows the fiber bundle guide unit  50  and the fiber bundle F at the twelve o&#39;clock position in  FIG. 4 . The supporting units  20  as shown in, e.g.,  FIG. 2  are omitted from the figure. 
     To begin, the controller  5  controls the moving motor  24  as shown in  FIG. 3  in the state in which the tip portions of the fiber bundles F are fixed to the front end portion of the mandrel M, and moves the supporting units  20  and the mandrel M forward from the rear side as shown in  FIGS. 14A and 16A . Because of this, the fiber bundles F are stuck from the front end portion to the rear end portion of the mandrel M (S 201 ). 
     Subsequently, the controller  5  moves the supporting units  20  further forward. Because of this, each fiber bundle supplied to the mandrel juts out as shown in  FIG. 14B  from the front end portion of the mandrel M (S 202 ). In this state, the controller  5  controls the guide moving motor  45  as shown in  FIG. 8  and activates the guide movement mechanism  80  as shown in  FIG. 8 , and moves the fiber bundle guide units  50  inward in the radial direction of the mandrel M (indicated by an arrow in  FIG. 14B ). Because of this, jut-out parts Fa of the fiber bundles F jutting out from the front end portion of the mandrel M are pulled inward in the radial direction of the mandrel M. In this state, an operator encloses the jut-out parts Fa with the ring guide  200  as shown in  FIG. 14B  described above (S 203 ). 
     When the jut-out parts Fa are enclosed with the ring guide  200 , the controller  5  moves the fiber bundle guide units  50  outward in the radial direction of the mandrel M, and puts the fiber bundle guide units  50  back to the positions at the time of the sticking. After that, while controlling the rotating motor  25  as shown in  FIG. 3  so that the mandrel M is rotated and moved in the circumferential direction by the width of the fiber bundle F, the controller  5  controls the moving motor  24  as shown in  FIG. 3  so that the supporting units  20  and the mandrel M are moved back to the rear side (S 204 ). In this example, a direction in which the mandrel M rotates is clockwise when viewed from the front. 
     In this way, the returning is performed to return the fiber bundles F back to the rear side while the fiber bundles F are guided from the inner side to the outer side in the radial direction of the ring guide  200  as shown in  FIG. 14C . Because the ring guide  200  is circular in cross section, the fiber bundles F are smoothly returned along the ring guide  200 . Therefore, when the fiber bundles F are easily broken such as pitch carbon fiber bundles and so on, the fiber bundles F are suppressed from being broken. In this stage, rotation and movement (returning) of the mandrel M may not be performed at the same time. One of these may be performed first, and the other may be performed later. In this example, because the rotational direction of the mandrel M in the returning is clockwise when viewed from the front, the lower fiber bundle F out of the fiber bundles F stuck on the mandrel M is hidden on the far side of the paper in  FIG. 14C  (same in the following figures). 
     The controller  5  moves the supporting units  20  further rearward, with the result that the ring guide  200  is pulled forward (toward the mandrel M) by the tension of the fiber bundles F as shown in  FIG. 14D . Because the pulled ring guide  200  is received by an end face of the mandrel M by contact therewith, the fiber bundles F are received by the ring guide  200  even when the fiber bundles F are pulled forward. Therefore, the fiber bundles F are suppressed from being peeled off from the mandrel M. 
     Subsequently, the controller  5  moves the supporting units  20  rearward as shown in  FIGS. 15A and 16B , and the fiber bundles F are stuck from the rear end portion to the front end portion of the mandrel M (S 205 ). In this stage, the operator does not remove the ring guide  200  yet. In other words, in this stage, the state in which the jut-out parts Fa are enclosed is maintained. Because the outer diameter of the ring guide  200  is substantially identical to the outer diameter of the mandrel M, the ring guide  200  is suppressed from interfering with the pressing roller  54 . 
     After that, the controller  5  moves the supporting units  20  further rearward to cause a part of each fiber bundle F to jut out as shown in  FIG. 15B  from the front end portion of the mandrel (S 206 ), and moves the fiber bundle guide units  50  inward in the radial direction of the mandrel M (indicated by an arrow in  FIG. 15B ). Subsequently, the operator encloses as shown in  FIG. 15B  a front jut-out part Fb by another ring guide  200  (ring guide  200   a ) that is different from the ring guide  200  enclosing the jut-out parts Fa (S 207 ). Furthermore, after moving the fiber bundle guide units  50  outward in the radial direction of the mandrel M, the controller  5  moves back the mandrel M forward while rotating the mandrel M in the circumferential direction by the width of the fiber bundle F (S 208 ). Because of this, it becomes possible to stick the fiber bundles F from the front end portion to the rear end portion of the mandrel M again as shown in  FIGS. 15C and 16C . 
     By repeating the above-described operations, the sticking of the fiber bundles F on the whole circumference of the mandrel M can be performed. In this regard, the operator does not remove the ring guide  200  until the 0-degree oriented layer is formed on the whole circumference of the mandrel M. The operator encloses jut-out parts of the fiber bundles F by another ring guide  200  at each returning. Therefore, the number of the ring guides  200  increases each time the returning is performed, and the ring guides  200  are aligned in the axial direction of the mandrel M. After the 0-degree oriented layer is formed on the whole circumference of the mandrel M, the both end portions of the fiber bundles F are fixed by, e.g., the hoop-winding as described above. Subsequently, by cutting the jut-out parts Fa and the like, the ring guides  200  become collectable. 
     As described above, as the fiber bundle F is pressed on the circumferential surface of the mandrel M by the pressing roller  54  of the fiber bundle guide unit  50 , the fiber bundle F is stuck onto the mandrel because of the viscosity of resin. Because of this, even when the mandrel M does not rotate and the tension applied to the fiber bundle F is low, the fiber bundle F can be stuck on the mandrel M before the fiber bundle F supplied to the mandrel M sags. As a result, the fiber bundle F is easily stuck on a target position. Therefore, the fiber bundle F is easily stuck along the axial direction of the mandrel M. 
     The tension applied to the fiber bundle F is received by the widening roller  53  placed upstream of the pressing roller  54 . Because of this, the tension is suppressed from being directly applied to the pressing roller  54  so that the pressing force of the pressing roller  54  is suppressed from becoming low. 
     Because the fiber bundle F runs smoothly along the widening roller  53 , the fiber bundle F is suppressed from being broken. 
     The positions of the fiber bundle guide units  50  are adjusted depending on the outer diameter of the mandrel M so that the fiber bundles F are pressed on the circumferential surface of the mandrel M having various outer diameters by the pressing rollers  54 . 
     The fiber bundle F is pressed on the circumferential surface of the mandrel M by the pressing roller  54 F when the mandrel M moves forward, and pressed on the circumferential surface of the mandrel M by the pressing roller  54 R when the mandrel M moves rearward. Because of this, the fiber bundle F is stuck on the mandrel M both when the mandrel M moves forward and when the mandrel M moves rearward. Therefore, the fiber bundle F is efficiently stuck on the mandrel M. 
     Because the pressing roller  54  has the reduced diameter part  55   a , the reduced diameter part  55   a  is facilitated to be along the circumferential surface of the mandrel M, with the result that a contact area between the pressing roller  54  and the mandrel circumferential surface is increased. Therefore, the fiber bundle F is stably stuck on the circumferential surface of the mandrel M. 
     The angle formed between the outer edge  55   e  of the roller end part  55   b  and the outer edge  55   d  of the reduced diameter part  55   a  is an obtuse angle. In other words, the end portion and its surroundings of the reduced diameter part  55   a  have a more gradual shape compared to when the reduced diameter part  55   a  (part likely to contact the fiber bundle) is formed to reach the end in the roller axial direction. Because of this, even when the end portion of the reduced diameter part  55   a  in the roller axial direction contacts the fiber bundle F already stuck on the mandrel M, the fiber bundle F is less likely to be peeled off. 
     Because the roller end portion is rectangular in cross section (i.e., the roller end portion is cylindrical, and the diameter of the roller end portion is consistent), processing in manufacture is facilitated. 
     Even when the pressing force of the pressing roller  54  is changed by some reasons, the variation of the pressing force is absorbed by the plate spring members  71  and  72 . Therefore, the following problems can be suppressed: the fiber bundle F is not stuck on the mandrel M successfully because the pressing force is decreased too much; and pressure to, e.g., the pressing roller  54  becomes excessive because the pressing force becomes excessive. 
     The plate spring members  71  and  72  support the pressing roller  54 , and absorb the variation of the pressing force of the pressing roller  54 . In other words, it is unnecessary to individually provide a member for supporting a pressing roller and a cushioning member. Therefore, increase in the number of components and cost growth are suppressed. 
     Because the pressing roller  54  is supported at both sides, the one end portion of the pressing roller  54  in the roller axial direction is suppressed from being displaced greatly as compared with the other end portion. As a result, the pressing roller  54  is suppressed from being tilted with respect to the circumferential surface of the mandrel M. Therefore, the fiber bundle F is stably stuck on the mandrel M. 
     By the controller  5 , after the fiber bundle F is stuck on the mandrel M by the movement of the supporting units  20  to one side in the axial direction, the part of each fiber bundle F is arranged to jut out from the end portion of the other side of the mandrel M. Subsequently, when the jut-out parts Fa of the fiber bundles are enclosed by the ring guide  200 , the supporting units  20  are moved back to the other side. As a result, the fiber bundles F are returned to the other side while being guided outward from the inner side in the radial direction of the ring guide  200 . As the supporting units  20  are further moved to the other side, the sticking of the fiber bundle F can be continued. Therefore, the fiber bundle F is continuously stuck on the mandrel M by the reciprocal movement of the mandrel M. Furthermore, when a pitch carbon fiber bundle which is easily broken is handled, the fiber bundle F is smoothly returned by the ring guide  200  which is circular in cross section, with the result that the fiber bundle F is suppressed from being broken. 
     By connecting the guide pieces  201  and  202 , it is possible to enclose the fiber bundles F from the outer side in the radial direction of the ring guide  200  while forming the ring guide  200 . In other words, when the fiber bundles F are enclosed by the ring guide  200 , the fiber bundles F are suppressed from making a contact with the ring guide  200 . As a result, damage to the fiber bundles F is suppressed. 
     Because the ring guide  200  is ring-shaped (i.e., has a smooth shape on the whole), damage to the fiber bundle F is suppressed. 
     Because the outer diameter of the ring guide  200  is substantially identical to the diameter of the mandrel M, the ring guide  200  is suppressed from protruding to the outside as compared to the mandrel in the radial direction, in a state in which the fiber bundles are enclosed by the ring guide  200 . Therefore, when the supporting units  20  are returned, the ring guide  200  is suppressed from interfering with, e.g., the pressing roller  54 . 
     The following will describe modifications of the above-described example. The members identical to those in the example described above will be denoted by the same reference numerals, and the explanations thereof are not repeated. 
     (1) In the example described above, the roller end parts  55   b  and  55   c  of the pressing roller  54  of the fiber bundle guide unit  50  are cylindrical in shape. However, this disclosure is not limited to this. In the radial direction of the pressing roller  54 , the roller end part  55   b  may be placed on the inner side of the tangent  101 . The roller end part  55   c  may be similarly arranged.
 
(2) In the example described above, the roller end parts  55   b  and  55   c  of the pressing roller  54  are shaped to suppress the fiber bundle F from being peeled off. However, this disclosure is not limited to this. In other words, the reduced diameter part  55   a  may be formed to reach the end portions of the pressing roller  54 . In the structure described above, for example, the fiber bundle F may be suppressed from being peeled off by adjusting the positional relationship between the pressing roller  54  and the mandrel M by using the guide movement mechanism  80 .
 
(3) In the example described above, the pressing roller  54  includes the reduced diameter part  55   a . However, this disclosure is not limited to this. For example, the entire pressing roller  54  may be cylindrical in shape.
 
(4) In the example described above, the pressing roller  54  is supported at both sides by the pressing roller supporter  52 . However, this disclosure is not limited to this. The pressing roller  54  may be cantilevered.
 
(5) In the example described above, the plate spring members  71  and  72  of the pressing roller supporter  52  function as supporting members which support the pressing roller  54  and cushioning members which absorb the variation of the pressing force. However, this disclosure is not limited to this. The pressing roller supporter  52  may include a supporting member and a cushioning member which are independent from each other.
 
(6) In the example described above, the widening roller  53  provided at the guide supporter  51  of the fiber bundle guide unit  50  is equivalent to the tension receiving member. However, this disclosure is not limited to this. For example, instead of the widening roller  53 , a fixed tension receiving member may be provided at the lower members  64  and  65  of the guide supporter  51 . In the structure, when a fiber bundle which is elastic and not easily broken is used, the tension of the fiber bundle can be received.
 
     Alternatively, the tension receiving member may not be provided at the guide supporter  51 . In the structure, for example, the tension of the fiber bundle may be kept low by moving the mandrel M slowly so that an influence on the pressing force of the pressing roller  54  may be suppressed. 
     (7) In the example described above, the mandrel M has a cylindrical shape. However, this disclosure is not limited to this. For example, when the outer diameter of the mandrel M changes in the axial direction, the guide movement mechanism  80  may be activated in the sticking of the fiber bundle F and the position of the fiber bundle guide unit  50  may be adjusted to cause the pressing roller  54  to generate constant pressing force.
 
(8) In this example, the helical winding unit  40  includes the guide movement mechanism  80 , and is able to stick the fiber bundles F on mandrels M with various outer diameters. However, this disclosure is not limited to this. For example, in the helical winding unit  40  which sticks the fiber bundles F only on a mandrel M having a predetermined outer diameter, the guide movement mechanism  80  may be omitted for cost reduction.
 
(9) In this example, the ring guide  200  used in the sticking of the fiber bundle F in a reciprocating manner is separable into the two guide pieces  201  and  202 . However, the ring guide  200  may be separable into three or more. In addition to that, guide pieces may not be completely separated and, for example, the guide pieces may be partially connected by a hinge.
 
(10) In the example described above, the ring guide  200  is ring-shaped. However, this disclosure is not limited to this. For example, as shown in  FIG. 17A , a ring guide  210  having a dodecagon shape may be used (in this regard, the ring guide  210  is separable into two guide pieces  211  and  212 ). In other words, the fiber bundle F may be returned by a guide tool that is not limited to ring-shaped but annular (“annular” means a shape which is able to enclose the fiber bundles F such as a polygon ring) in shape. In this regard, preferably, the maximum outer diameter (i.e., the size between apexes in the radial direction) of the ring guide  210  is equal to or shorter than the outer diameter of the mandrel M to suppress the ring guide  210  from interfering with the pressing roller  54 .
 
(11) In the example described above, the ring guide  200  can be separated. However, this disclosure is not limited to this. For example, as shown in  FIG. 17B , a ring guide  220  may have a slit  221 , and may enclose the fiber bundles F by guiding the fiber bundles to the inside of the ring. The shape of this ring guide  220  is also annular. In this example, the fiber bundles F need to be handled carefully, for example, by hand to not damage the fiber bundles F when the fiber bundles F are enclosed by the ring guide  220 .
 
(12) In the example described above, the fiber bundle F is returned by, e.g., the ring guide  200 . However, this disclosure is not limited to this. For example, the fiber bundle F may be stuck in a reciprocating manner as described below. After the fiber bundle F is stuck to the rear end portion from the front end portion of the mandrel M, the fiber bundle F is cut and the mandrel M is rotated a little. Subsequently, the tip portion of the fiber bundle F which has not been stuck on the mandrel M is fixed to the rear end portion of the mandrel M. Subsequently, the fiber bundle F is stuck to reach the front end portion from the rear end portion of the mandrel M by moving the mandrel M to the rear side from the front side. By repeating the above-described operation, the fiber bundle F may be stuck on the mandrel M.
 
(13) In this example, in the sticking, the mandrel M is moved in the axial direction without being rotated. Alternatively, by moving the mandrel M in the axial direction while rotating the same a little, a layer which is tilted a little from the axial direction may be formed.
 
(14) In the example described above, the supporting units  20  are able to reciprocate, and the fiber bundle guide unit  50  includes the two pressing rollers  54 F and  54 R. However, this disclosure is not limited to this. In other words, as shown in  FIG. 18 , the filament winding device  1   a  may be provided with helical winding units  40   a  aligned in the front-rear direction, and a fiber bundle guide unit  50   a  attached to each helical winding unit  40   a  may include only one pressing roller  54 . Because of this, by the helical winding units  40   a , the 0-degree oriented layer may be formed on the whole circumference of the mandrel M.