Patent Publication Number: US-2023157268-A1

Title: Spool braking device for dual bearing reel

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to Japanese Patent Application No. 2021-190084, filed Nov. 24, 2021, and Japanese Patent Application No. 2022-072573, filed Apr. 26, 2022. The contents of those applications are incorporated by reference herein in their entireties. 
     TECHNICAL FIELD 
     The present invention relates to a spool braking device for a dual bearing reel. 
     BACKGROUND ART 
     Some dual bearing reels are equipped with a spool braking device that uses centrifugal force to brake the rotation of a spool (see Japanese Laid-Open Patent Application No. 2016-202123). A spool and a rotary member are attached to a spool shaft in a spool braking device. Brake shoes are attached to the rotary member in a swingable manner. The brake shoes swing with a brake drum in accordance with the rotation of the spool via the rotary member. 
     In a conventional spool braking device, when a spool and a rotary member rotate with a spool shaft, centrifugal force proportional to the square of the rotational speed of the rotary member acts on brake shoes, and frictional force is generated between the brake shoes and the brake drum. In other words, the greater the rotational speed of the spool and the rotary member, the more the braking force on the spool increases. 
     Therefore, if the braking force on the spool suddenly becomes too large when the rotational speed of the spool and the rotary member is high, the flying distance may decrease. Also, when the rotational speed of the spool and the rotary member decreases from the state in which the rotational speed of the spool and the rotary member is high, the frictional force suddenly becomes small and the braking force on the spool may become too small. In this case, there is a likelihood that backlash occurs. 
     BRIEF SUMMARY 
     The object of the present invention is to provide a spool braking device for a dual bearing reel, that is configured to apply a suitable braking force to a spool. 
     A spool braking device for a dual bearing reel according to one aspect of the present invention brakes a spool, rotating integrally with a spool shaft that is rotatably supported by a reel body, using centrifugal force. 
     The spool braking device includes a brake drum and a rotation structure. The brake drum is disposed in the reel body. The brake drum is positioned alongside the spool in an axial direction in which a rotation axial center of the spool shaft extends. The brake drum has a tapered surface, whose diameter is reduced towards the spool, on an outer peripheral surface thereof. 
     The rotation structure is arranged between the spool and the brake drum in the axial direction. The rotation structure has a support, a brake shoe, and a biasing member. The support rotates in accordance with the spool shaft. The brake shoe is swingably supported by the support. The center of gravity of the brake shoe is positioned to be outside of the brake drum in a radial direction away from the rotation axial center. The brake shoe comes in contact with the tapered surface of the brake drum. 
     The biasing member biases one of the support or the brake drum towards another one of the support or the brake drum. The one of the support or the brake drum is arranged so as to be movable in the axial direction with respect to the another one of the support or the brake drum. 
     In the spool braking device, when the rotational speed of the spool and the support increases in a state in which the brake shoe is in contact with the tapered surface of the brake drum, the braking force of the brake shoe on the tapered surface of the brake drum increases, and the support and the brake drum are separated from each other. With this, the brake shoe comes in contact with the tapered surface at the small diameter side, and thus, the braking force on the spool can be reduced. That is, with the spool braking device according to the present invention, it is possible to solve the problem of conventional technology, such as reduction in flying distance due to the increase in the braking force on the spool. 
     Also, in the spool braking device according to the present invention, when the rotational speed of the spool and the support decreases from a state in which the rotational speed of the spool and the support is high, the support and the brake drum come closer to each other due to the biasing member. With this, the brake shoe comes in contact with the brake drum at the large diameter side, and thus, the braking force on the spool can be recovered. That is, with the spool braking device, it is possible to solve the problem of conventional technology, such as backlash due to the decrease in the braking force on the spool. 
     In the spool braking device for a dual bearing reel according to another aspect of the present invention, it is preferable that the rotation structure further includes a cam mechanism. In this case, the cam mechanism guides the support, which is axially movable with respect to the brake drum, in the axial direction away from the brake drum. The support is arranged between the cam mechanism and the biasing member in the axial direction. This configuration allows one of the support or the brake drum to be suitably moved in the axial direction with respect to another one of the support or the brake drum. 
     In the spool braking device for a dual bearing reel according to another aspect of the present invention, it is preferable that the cam mechanism includes a first cam section and a second cam section. In this case, the first cam section has a first body which rotates integrally with the spool shaft, and a protrusion which protrudes from the first body towards the support. The second cam section has a second body which rotates integrally with the support, and a recess disposed in the second body and engaged with the protrusion. Here, the protrusion has a pair of sloped surfaces facing each other in a circumferential direction around the rotation axial center. The circumferential interval between the pair of sloped surfaces decreases in the axial direction towards the spool. 
     In the spool braking device for a dual bearing reel according to another aspect of the present invention, it is preferable that the rotation structure further includes a positioning member. The positioning member is configured to position the support to an initial position. The support is movable in the axial direction with respect to the brake drum. The support is arranged between the positioning member and the biasing member in the axial direction. This configuration allows the support to be suitably positioned at the initial position. 
     In the spool braking device for a dual bearing reel according to another aspect of the present invention, the cam mechanism includes a first cam section and a second cam section. The first cam section has a first body which rotates integrally with a spool shaft, and a protrusion which protrudes from the first body towards the support. The second cam section has a second body which is arranged to face the first body in the axial direction and rotates integrally with the support, and a recess disposed in the second body and engaged with the protrusion. This configuration allows the cam mechanism to be suitably operated. 
     In the spool braking device for a dual bearing reel according to another aspect of the present invention, the cam mechanism includes a first cam section and a second cam section. The first cam section includes a first body, and a protrusion. The first body has a cylindrical part which rotates integrally with the spool shaft, and a flange which extends radially outward from the cylindrical part. The protrusion protrudes from the flange towards the support. The second cam section includes a second body, and a recess. The second body is disposed on an outer peripheral surface of the cylindrical part axially between the flange and the support, and rotates integrally with the support. The recess is disposed in the second body and engaged with the protrusion. 
     In this configuration, the second body of the second cam section is arranged on the outer peripheral surface of the cylindrical part axially between the flange and the support. In this state, the second cam section approaches or moves away from the first cam section on the outer peripheral surface of the cylindrical part. This allows the second cam section to be stably moved in the axial direction. 
     In the spool braking device for a dual bearing reel according to another aspect of the present invention, the cam mechanism includes a first cam section and a second cam section. The first cam section includes a first body which rotates integrally with the spool shaft, and a protrusion which protrudes from the first body towards the support. The second cam section includes a second body, a recess, and a boss. The second body rotates integrally with the support. The recess disposed in the second body and engaged with the protrusion. The boss protrudes from the second body. The first body has a non-circular hole which engages non-rotatably relative to an outer peripheral surface of the spool shaft, and a circular hole which communicates with the non-circular hole. The boss is arranged between the spool shaft and the circular hole in the radial direction. 
     In this configuration, in a state in which a tip of the boss is arranged in the circular hole of the first cam section, the second cam section approaches or moves away from the first cam section on the spool shaft. This allows the second cam section to be stably moved in the axial direction. 
     With a spool braking device for a dual bearing reel according to the present invention, it is possible to suitably apply braking force on a spool. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of an external appearance of a dual bearing reel according to an embodiment of the present invention. 
         FIG.  2    is a cross-sectional view of the dual bearing reel. 
         FIG.  3    is a perspective view of a frame, a spool, a spool shaft, and a rotation structure. 
         FIG.  4    is an enlarged cross-sectional view of the vicinity of the rotation structure. 
         FIG.  5    is a perspective view of a cam mechanism. 
         FIG.  6    is an enlarged cross-sectional view of the vicinity of a rotation structure according to a first variation. 
         FIG.  7    is an enlarged cross-sectional view of the vicinity of a rotation structure according to a second variation. 
         FIG.  8    is a perspective view of a cam mechanism according to a third variation. 
         FIG.  9    is a perspective view of a cam mechanism according to a fourth variation. 
     
    
    
     DETAILED DESCRIPTION 
     As shown in  FIG.  1   , a dual bearing reel  1 , in which one embodiment of the present invention is employed, includes a reel body  3 , a spool  5 , and a handle  7 . As shown in  FIG.  2   , the dual bearing reel  1  further includes a spool shaft  11  and a spool braking device  13 . 
     Here, the axial direction refers to the direction in which the rotation axial center X 1  of the spool shaft  11  extends. The radial direction refers to the direction from which the rotation axial center X 1  of the spool shaft  11  perpendicularly apart. The circumferential direction refers to the direction around the rotation axial center X 1  of the spool shaft  11 . 
     As shown in  FIG.  2   , the reel body  3  has a frame  31 , a first side cover  33 , and a second side cover  35 . The frame  31  has a first side plate  31   a , a second side plate  31   b , and a plurality of joint sections  31   c.    
     The first side plate  31   a  and the second side plate  31   b  are arranged so as to be spaced apart from each other in the axial direction. The first side plate  31   a  and the second side plate  31   b  are connected to each other via the plurality of joint sections  31   c . The first side plate  31   a , the second side plate  31   b , and the plurality of joint sections  31   c  are integrally formed. 
     The first side cover  33  is attached to the frame  31 . The first side cover  33  covers the first side plate  31   a . For example, the first side cover  33  covers the first side plate  31   a  on the opposite side of the handle  7 . The first side cover  33  has a cylinder-shaped shaft support  34 . 
     The shaft support  34  is disposed outside of the spool shaft  11  in the radial direction. The shaft support  34  rotatably supports the spool shaft  11  via a bearing  37 . Between the first side cover  33  and the first side plate  31   a , an operating member  61  (described below) is arranged so as to axially move a brake drum  51  (described below) of the spool braking device  13 . 
     The second side cover  35  is attached to the frame  31 . The second side cover  35  covers the second side plate  31   b . For example, the second side cover  35  covers the second side plate  31   b  between the handle  7  (see  FIG.  1   ) and the second side plate  31   b . A rotation transmission mechanism  10  for transmitting the rotation of the handle  7  to the spool  5  is arranged between the second side cover  35  and the second side plate  31   b.    
     The spool  5  is rotatably supported by the reel body  3 . For example, the spool  5  is rotatably supported by the reel body  3  via the spool shaft  11 . The spool  5  has a spool body portion  5   a , a boss  5   b , and an annular wall portion  5   c . A fishing line is wound around the spool body portion  5   a . The boss  5   b  is attached to the spool shaft  11  so as to rotate integrally with the spool shaft  11 . The annular wall portion  5   c  connects the spool body portion  5   a  and the boss  5   b . For example, the annular wall portion  5   c  is integrally formed with the spool body portion  5   a  and the boss  5   b.    
     As shown in  FIG.  1   , the handle  7  is rotatably attached to the reel body  3 . For example, the handle  7  is rotatably supported by the reel body  3  via a drive shaft  10   a  shown in  FIG.  2   . 
     The rotation transmission mechanism  10  shown in  FIG.  2    is a mechanism which transmits the rotation of the handle  7  to the spool shaft  11 . The rotation transmission mechanism  10  is arranged between the second side cover  35  and the second side plate  31   b . The rotation transmission mechanism  10  has the drive shaft  10   a  which rotates integrally with the handle  7 , a drive gear  10   b  which rotates integrally with the drive shaft  10   a , and a pinion gear  10   c  which meshes with the drive gear  10   b.    
     When the handle  7  rotates, the drive shaft  10   a , the drive gear  10   b , and the pinion gear  10   c  rotate. The spool shaft  11  is inserted into the inner peripheral part of the pinion gear  10   c . The rotation from the pinion gear  10   c  to the spool shaft  11  is transmitted via a clutch mechanism (not shown). 
     As shown in  FIG.  2   , the spool shaft  11  is rotatably supported by the reel body  3 . For example, the spool shaft  11  is rotatably supported by the shaft support  34  of the first side cover  33  and the second side plate  31   b  via the bearing  37  and a bearing  39 . The spool  5  is attached to the spool shaft  11 . 
     The spool braking device  13  brakes the spool  5 , which rotates integrally with the spool shaft  11 , using centrifugal force. As shown in  FIG.  2   , the spool braking device  13  includes the brake drum  51  and a rotation structure  53 . 
     The brake drum  51  is positioned alongside the spool  5  in the axial direction. The brake drum  51  is arranged outside of the shaft support  34  of the first side cover  33  in the radial direction. The brake drum  51  is arranged radially inside of a brake shoe  67  (described below). The brake drum  51  is disposed in the reel body  3 . For example, the brake drum  51  is attached to the shaft support  34  of the first side cover  33  via a moving mechanism  55 . 
     As shown in  FIGS.  3  and  4   , the brake drum  51  includes a drum body  57  and a tapered surface  58 . The drum body  57  is formed in a cylindrical shape. The drum body  57  is disposed on the outer peripheral surface of the shaft support  34 . The tapered surface  58  is formed at one end of the drum body  57 . For example, the tapered surface  58  is formed on the outer peripheral surface of one end of the drum body  57 . The tapered surface  58  is reduced in diameter towards the spool  5 . In other words, the outer diameter of the tapered surface  58  decreases as approaching the spool  5 . 
     As shown in  FIG.  2   , the brake drum  51  is configured to be movable in the axial direction by the moving mechanism  55 . The moving mechanism  55  is mounted on the first side cover  33 . The moving mechanism  55  is arranged between the first side cover  33  and the first side plate  31   a . The moving mechanism  55  has the operating member  61  and a drum cam  63 . 
     The operating member  61  is operated when the brake drum  51  is moved in the axial direction. The operating member  61  is attached so as to be rotatable with respect to the reel body  3 , for example, the shaft support  34  of the first side cover  33 . The operating member  61  has an annular shape. The operating member  61  is arranged outside of the brake drum  51  in the radial direction. The operating member  61  is axially positioned by a lid member  62  that is attached to the first side cover  33 . The operating member  61  engages with the brake drum  51  and the drum cam  63 . 
     For example, as shown in  FIGS.  3  and  4   , grooves  51   a , extending in the axial direction, are formed on the outer peripheral surface of the brake drum  51 . First convex portions  61   a , protruding radially inward, are formed on the inner peripheral surface of the operating member  61 . The first convex portions  61   a  engage with the grooves  51   a  of the brake drum  51 . As a result, the operating member  61  and the brake drum  51  rotate integrally, and the brake drum  51  moves in the axial direction with respect to the operating member  61 . 
     As shown in  FIG.  4   , the drum cam  63  moves the brake drum  51  in the axial direction. The drum cam  63  is provided on the outer peripheral surface of the shaft support  34 . For example, the drum cam  63  is arranged between the shaft support  34  and the brake drum  51  in the radial direction. The drum cam  63  engages with the brake drum  51  and moves the brake drum  51  in the axial direction. 
     For example, as shown in  FIG.  3   , second convex portions  51   b , protruding radially inward, are formed on the inner peripheral surface of the brake drum  51 . As shown in  FIG.  4   , a helical groove  63   a , extending in the circumferential direction and the axial direction, is formed on the outer peripheral surface of the drum cam  63 . The second convex portions  51   b  engage with the helical groove  63   a . In this state, when the operating member  61  and the brake drum  51  integrally rotate, the second convex portions  51   b  move along the helical groove  63   a . As a result, the brake drum  51  moves in the axial direction while rotating in the circumferential direction. 
     As shown in  FIG.  2   , the rotation structure  53  is arranged between the spool  5  and the brake drum  51  in the axial direction. The rotation structure  53  rotates in accordance with the spool shaft  11 . As shown in  FIG.  3   , the rotation structure  53  includes a shoe support  65 , a plurality (four, for example) of brake shoes  67 , and a coil spring  69  (one example of biasing member). The rotation structure  53  further includes a stopper ring  71  (one example of positioning member). The rotation structure  53  further includes a cam mechanism  73 . 
     The shoe support  65  swingably supports the brake shoes  67 . The shoe support  65  rotates in accordance with the spool shaft  11 . For example, the shoe support  65  rotates with the spool shaft  11  via the cam mechanism  73 . The shoe support  65  is formed in a disc shape. For example, the shoe support  65  is formed in a bowl shape. 
     As shown in  FIG.  4   , the shoe support  65  is arranged between the stopper ring  71  and the coil spring  69  in the axial direction. For example, the shoe support  65  is arranged between the cam mechanism  73  and the coil spring  69  in the axial direction. In detail, the shoe support  65  is arranged between a first flange  77   a   2  (described below) of a second cam section  77  and the coil spring  69  in the axial direction. 
     The shoe support  65  is arranged radially outside of the spool shaft  11 . The shoe support  65  is configured to be axially movable with respect to the brake drum  51 . For example, the shoe support  65  axially moves with the second cam section  77  with respect to the brake drum  51 . The shoe support  65  is attached to a first cylindrical part  77   a   1  (described below) of the second cam section  77  so as to rotate integrally with the second cam section  77 . The shoe support  65  and the second cam section  77  rotate with the spool shaft  11  via a first cam section  75  (described below) of the cam mechanism  73 . 
     As shown in  FIG.  4   , the plurality of brake shoes  67  are configured to be able to contact the brake drum  51 . The plurality of brake shoes  67  are swingably supported by the shoe support  65 . For example, each brake shoe  67  is swingably supported on the outer peripheral part of the shoe support  65  via a swing shaft  68 . Each brake shoe  67  is circumferentially spaced apart from each other. 
     The center of gravity G of each brake shoe  67  is positioned outside the brake drum  51  in the radial direction. For example, when the shoe support  65  rotates, centrifugal force acts on the center of gravity G of each brake shoe  67 , causing each brake shoe  67  to swing around the swing shaft  68 . As a result, each brake shoe  67  comes in contact with the tapered surface  58  of the brake drum  51 . 
     As shown in  FIG.  4   , the coil spring  69  biases the shoe support  65  towards the brake drum  51 . The coil spring  69  is arranged between the spool  5  and the shoe support  65  axially in a compressed state. For example, one end of the coil spring  69  is arranged radially outside of the boss  5   b  of the spool  5  and comes in contact with the annular wall portion  5   c  of the spool  5 . The other end of the coil spring  69  comes in contact with the shoe support  65 . 
     The stopper ring  71  is used to position the shoe support  65  at an initial position. The stopper ring  71  has a C-shape. The stopper ring  71  is attached to the spool shaft  11 . For example, the stopper ring  71  is attached to an annular groove  11   a  (see  FIG.  3   ) of the spool shaft  11 . 
     The cam mechanism  73 , shown in  FIGS.  3  and  4   , guides the shoe support  65  in the axial direction away from the brake drum  51 . The cam mechanism  73  has the first cam section  75  and the second cam section  77 . As shown in  FIG.  4   , the first cam section  75  is arranged between the stopper ring  71  and the second cam section  77  in the axial direction. The first cam section  75  comes in contact with the stopper ring  71 . The first cam section  75  engages with the second cam section  77 . 
     As shown in  FIG.  5   , the first cam section  75  includes a first body  75   a  and a plurality (two, for example) of protrusions  75   b . The first body  75   a  is attached to the spool shaft  11  so as to rotate integrally with the spool shaft  11 . For example, the first body  75   a  is formed in a disc shape. The first body  75   a  is attached to the outer surface of the spool shaft  11  by non-circular engagement. 
     As a result, the first body  75   a  rotates integrally with the spool shaft  11 . The first body  75   a  is arranged between a step wall  11   b  (see  FIG.  3   ) of the spool shaft  11  and the stopper ring  71 . With this configuration, the axial movement of the first body  75   a  with respect to the spool shaft  11  is restricted. 
     The plurality of protrusions  75   b  are integrally formed with the first body  75   a . The plurality of protrusions  75   b  protrude from the first body  75   a  towards the shoe support  65 . The plurality of protrusions  75   b  are spaced apart from each other in the circumferential direction. Each protrusion  75   b  has a pair of sloped surfaces  75   b   1  facing each other in the circumferential direction. The circumferential interval of the pair of sloped surfaces  75   b   1  decreases towards the spool  5 . 
     As shown in  FIG.  5   , the second cam section  77  has a second body  77   a , and a plurality (two, for example) of recesses  77   b . The second body  77   a  is attached to the spool shaft  11  so as to rotate integrally with the shoe support  65 . The second body  77   a  is arranged so as to face the first body  75   a  in the axial direction. 
     For example, the second body  77   a  has the first cylindrical part  77   a   1  and the first flange  77   a   2 . The first cylindrical part  77   a   1  is disposed on the outer peripheral surface of the spool shaft  11 . The first cylindrical part  77   a   1  axially moves with respect to the spool shaft  11 . The shoe support  65  is fixed to the outer peripheral surface of the first cylindrical part  77   a   1 , and the first cylindrical part  77   a   1  rotates integrally with the shoe support  65 . 
     The first flange  77   a   2  extends radially outward from the first cylindrical part  77   a   1 . The first flange  77   a   2  has an annular shape. As shown in  FIG.  4   , the first flange  77   a   2  is arranged between the shoe support  65  and the first cam section  75  (the first body  75   a ) in the axial direction. 
     As shown in  FIG.  5   , the plurality of recesses  77   b  are formed in the second body  77   a . For example, the plurality of recesses  77   b  are formed in the first flange  77   a   2 . The plurality of recesses  77   b  are spaced apart from each other in the circumferential direction. 
     The plurality of recesses  77   b  are arranged to face the plurality of protrusions  75   b  of the first cam section  75 , respectively. The plurality of recesses  77   b  engage with the plurality of protrusions  75   b  of the first cam section  75 , respectively. The wall of each recess  77   b  is formed along the sloped surfaces  75   b   1  of each protrusion  75   b . The wall of each recess  77   b  is slidable with the sloped surfaces  75   b   1  of the protrusion  75   b.    
     In the spool braking device  13  having the above-described configuration, the spool  5  and the spool shaft  11  rotate in a state in which the plurality of recesses  77   b  of the second cam section  77  are engaged with the plurality of protrusions  75   b  of the first cam section  75 . In this state, the rotation of the spool shaft  11  is transmitted from the first cam section  75  to the second cam section  77  and then, transmitted from the second cam section  77  to the shoe support  65 . 
     This causes the spool shaft  11 , the cam mechanism  73  (the first cam section  75  and the second cam section  77 ), and the shoe support  65  to rotate. In this state, the brake shoes  67  are in contact with the tapered surface  58  of the brake drum  51 , and the brake shoes  67  slide with respect to the tapered surface  58  of the brake drum  51 . 
     Here, if the rotational speed of the spool  5  (the rotational speed of the shoe support  65 ) becomes high and the force of the brake shoes  67  biasing the tapered surface  58  of the brake drum  51  increases, the shoe support  65  axially moves away from the brake drum  51  due to the reaction force acting on the brake shoes  67  from the tapered surface  58  of the brake drum  51 . 
     This causes the brake shoes  67  to contact the small diameter side of the tapered surface  58 , therefore, it is possible to decrease the braking force on the spool  5 . In other words, the spool braking device  13  can suitably apply a braking force to the spool  5  so as not to reduce the flying distance even when the rotational speed of the spool  5  becomes high. 
     Also, if the rotational speed of the spool  5  decreases from the state in which the rotational speed of the spool  5  (the rotational speed of the shoe support  65 ) is high, the reaction force acting on the brake shoes  67  from the tapered surface  58  of the brake drum  51  reduces, and thus, the shoe support  65  is pressed by the coil spring  69  and approaches the brake drum  51 . 
     This causes the brake shoes  67  to contact the large diameter side of the brake drum  51 , therefore, it is possible to recover the braking force on the spool  5 . In other words, the spool braking device  13  can suitably apply a braking force to the spool  5  not to generate backlash even when the rotational speed of the spool  5  reduces from high speed. 
     (Variations) 
     The above-described embodiment can be modified as in the first variation below. 
     First Variation 
     In the above-described embodiment, an example was given of a case in which the shoe support  65  axially moves with respect to the brake drum  51 . Instead of this configuration, as shown in  FIG.  6   , the brake drum  51  can be configured to axially move with respect to the shoe support  65 . 
     In this case, the shoe support  65  is press-fitted into the spool shaft  11  and comes in contact with an annular convex portion  11   c  of the spool shaft  11 . In this manner, the shoe support  65  is attached to the spool shaft  11  in an axially non-movable and non-rotatable manner. A coil spring  169  (one example of biasing member) is arranged between the brake drum  51  and the first side cover  33  in the axial direction. 
     For example, a step part  57   a  is formed at the other end of the drum body  57  of the brake drum  51 . One end of the coil spring  169  is disposed on the outer peripheral surface of the step part  57   a . The one end of the coil spring  169  is in contact with the wall of the step part  57   a . The other end of the coil spring  169  is disposed outside of the shaft support  34  of the first side cover  33 , for example, outside of a pushing cam  163 , in the radial direction. The other end of the coil spring  169  is in contact with a pushing member  165 . An O-ring  170  is arranged to restrict the brake drum  51  from slipping out of the shaft support  34  of the first side cover  33  at the tip of the shaft support  34  of the first side cover  33 . 
     In this case, by operating the operating member  61 , the pushing member  165  is axially moved by the pushing cam  163 . This changes the strength of the biasing force with which the pushing member  165  biases the coil spring  169 . Incidentally, the movement of the pushing member  165  is the same as the movement of the drum cam  63  of the moving mechanism  55  in the above-described embodiment. 
     With this configuration, the brake drum  51  moves away from the shoe support  65  when the rotational speed of the spool  5  (the rotational speed of the shoe support  65 ) becomes high, thereby, the brake shoes  67  can be brought into contact with the tapered surface  58  on the small diameter side. As a result, even when the rotational speed of the spool  5  becomes high, a braking force can be suitably applied to the spool  5  so as not to decrease the flying distance. 
     Also when the rotational speed of the spool  5  decreases from the state in which the rotational speed of the spool  5  (the rotational speed of the shoe support  65 ) is high, the brake drum  51  is biased by the coil spring  169  and approaches the shoe support  65 , thereby, the brake shoes  67  can be brought into contact with the brake drum  51  on the large diameter side. As a result, even when the rotational speed of the spool  5  decreases from high speed, a braking force can be suitably applied to the spool  5  so as not to generate backlash. 
     Second Variation 
     The cam mechanism  73  in the above-described embodiment can be configured as follows. As shown in  FIG.  7   , a cam mechanism  173  includes a first cam section  175  and a second cam section  177 . The first cam section  175  includes a cylindrical first body  175   a , and the plurality (two, for example) of protrusions  75   b  (see  FIG.  5   ) provided on the outer peripheral part of the cylindrical first body  175   a . The first body  175   a  has a second cylindrical part  175   a   1  (one example of cylindrical part) and a second flange  175   a   2  (one example of flange). 
     The second cylindrical part  175   a   1  is formed in a cylindrical shape. The inner surface of the second cylindrical part  175   a   1  engages with the outer surface of the spool shaft  11  by non-circular engagement. As a result, the second cylindrical part  175   a   1  rotates integrally with the spool shaft  11 . The second cylindrical part  175   a   1  is arranged between a step wall  111   b  of the spool shaft  11  and the stopper ring  71 . With this configuration, the axial movement of the second cylindrical part  175   a   1  with respect to the spool shaft  11  is restricted. 
     The second flange  175   a   2  extends radially outward from the second cylindrical part  175   a   1 . The second flange  175   a   2  is integrally formed with the second cylindrical part  175   a   1 . The second flange  175   a   2  is formed in an annular shape. The plurality of protrusions  75   b  (see  FIG.  5   ) are provided on the second flange  175   a   2 . The plurality of protrusions  75   b  protrude from the second flange  175   a   2  in the axial direction. 
     The second cam section  177  includes a second body  177   a  and the plurality (two, for example) of recesses  77   b  (see  FIG.  5   ). The second body  177   a  is attached to the shoe support  65  so as to rotate integrally with the shoe support  65 . The second body  177   a  can be integrally formed with the shoe support  65 . 
     The second body  177   a  is formed in a cylindrical shape. The second body  177   a  is disposed on the outer peripheral surface of the second cylindrical part  175   a   1  between the second flange  175   a  and the shoe support  65  in the axial direction. The second body  177   a  rotates relative to the second cylindrical part  175   a   1 . The plurality of recesses  77   b  (see  FIG.  5   ) are provided to the second body  177   a . The plurality of recesses  77   b  engage with the plurality of protrusions  75   b , respectively. 
     In this configuration, the cam receiving portion  177  (the second body  177   a ) is disposed on the outer peripheral surface of the second cylindrical part  175   a   1  between the second flange  175   a   2  of the first cam section  175  and the shoe support  65  in the axial direction. In this state, the second cam section  177  moves closer to or away from the first cam section  175  along the outer peripheral surface of the second cylindrical part  175   a   1 . This allows the second cam section  177  to move stably in the axial direction. 
     Third Variation 
     The cam mechanism  73  in the above-described embodiment can be configured as follows. As shown in  FIG.  8   , a cam mechanism  273  includes a first cam section  275  and a second cam section  277 . The first cam section  275  has a cylindrical first body  275   a  and the plurality (two, for example) of protrusions  75   b  provided on the outer peripheral part of the cylindrical first body  275   a . The first body  275   a  rotates integrally with the spool shaft  11  and is restricted from axial movement relative to the spool shaft  11 . 
     The first body  275   a  includes a non-circular hole  275   a   1  and a circular hole  275   a   2 . The non-circular hole  275   a   1  engages with the outer peripheral surface of the spool shaft  11  so as not to be rotatable relative to the outer peripheral surface of the spool shaft  11 . In this manner, the first body  275   a  rotates integrally with the spool shaft  11 . That is, the first cam section  275  rotates integrally with the spool shaft  11 . 
     The circular hole  275   a   2  is provided so as to communicate with the non-circular hole  275   a   1 . A boss  77   c  (described below) of the second cam section  277  is disposed at the circular hole  275   a   2 . The plurality of protrusions  75   b  are provided to the first body  275   a . The plurality of protrusions  75   b  protrude in the axial direction from the first body  275   a.    
     The second cam section  277  includes the second body  77   a , the plurality (two, for example) of recesses  77   b , and the boss  77   c . The configuration of the second body  77   a  and the configuration of the plurality of recesses  77   b  are the same as the configurations of the above-described embodiment. For the same configurations as in the previous embodiment, the description of the above-described embodiment applies. 
     The boss  77   c  protrudes from the second body  77   a . For example, the boss  77   c  extends in the axial direction from the first cylindrical part  77   a   1 . The boss  77   c  and the first cylindrical part  77   a   1  are disposed on the outer peripheral surface of the spool shaft  11 . The boss  77   c  and the first cylindrical part  77   a   1  rotate relative to the spool shaft  11  and axially move with respect to the spool shaft  11 . 
     The boss  77   c  is disposed in the circular hole  275   a   2  of the first cam section  275 . For example, in a state in which the tip of the boss  77   c  is disposed in the circular hole  275   a   2 , the tip of the boss  77   c  is located between the inner peripheral surface of the circular hole  275   a   2  and the outer peripheral surface of the spool shaft  11  in the radial direction. 
     In this configuration, in a state in which the tip of the boss  77   c  of the second cam section  277  is disposed in the circular hole  275   a   2  of the first cam section  275 , the second cam section  277  moves closer to or away from the first cam section  275  along the spool shaft  11 . This allows the second cam section  277  to move stably in the axial direction. 
     Fourth Variation 
     The cam mechanism  73  in the above-described embodiment can be configured as follows. As shown in  FIG.  9   , a cam mechanism  373  includes the first cam section  275  and a second cam section  377 . The configuration of the first cam section  275  is the same as the configuration in the third variation. For the same configurations as in the third variation, the description of the third variation applies. 
     The second cam section  377  includes a second body  377   a , the plurality (two, for example) of recesses  77   b , and the boss  77   c . The second body  377   a  is formed in a cylindrical shape. The second body  377   a  is disposed on the outer peripheral surface of the spool shaft  11 . The shoe support  65  shown in  FIGS.  3  and  4    is attached to the outer peripheral surface of the second body  377   a . The shoe support  65  rotates integrally with the second body  377   a.    
     The plurality of recesses  77   b  are provided on the outer peripheral part of the second body  377   a . The boss  77   c  protrudes from the second body  377   a . The boss  77   c  is disposed on the outer peripheral surface of the spool  11 . The second body  377   a  and the boss  77   c  rotate relative to the spool shaft  11  and axially move with respect to the spool shaft  11 . 
     In this configuration, as in the third variation, in a state in which the tip of the boss  77   c  of the second cam section  377  is disposed in the circular hole  275   a   2  of the first cam section  275 , the second cam section  377  moves closer to or away from the first cam section  275  along the spool shaft  11 . This allows the second cam section  377  to move stably in the axial direction. 
     REFERENCE SIGNS LIST 
     
         
           1  Dual bearing reel 
           3  Reel body 
           5  Spool 
           11  Spool shaft 
           13  Spool braking device 
           51  Brake drum 
           53  Rotation Structure 
           57  Drum body 
           58  Tapered surface 
           65  Shoe support 
           67  Brake shoe 
           69 ,  169  Coil spring 
           71  Stopper ring 
           73  Cam mechanism 
           75 ,  175 ,  275  First cam section 
           75   a ,  175   a ,  275   a  First body 
           75   b  Protrusion 
           75   b   1  Sloped surface 
           77 ,  177 ,  277 ,  377  Second cam section 
           77   a ,  177   a ,  277   a ,  377   a  Second body 
           77   b  Recess 
           77   c  Boss 
           175   a   1  Second cylindrical part 
           175   a   2  Second flange 
           275   a   1  Non-circular hole 
           275   a   2  Circular hole 
         G Center of gravity of brake shoe 
         X 1  Rotation axial center