# Patent

## Title
Engaging pin and reciprocating mechanism for fishing reel having engaging pin

## Abstract

An engagement pin of a fishing reel for engaging a worm shaft of the fishing reel, the worm shaft having intersecting spiral grooves, the engagement pin includes a shaft portion and an engagement portion. The shaft portion has an end. The engagement portion is integrally and turnably disposed on the end of the shaft portion and is configured to engage the intersecting spiral grooves. At least the engagement portion is formed from synthetic resin.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority based on Japanese Patent Application No. 2015-015181, filed in Japan Patent Office on Jan. 29, 2015, the contents of which is hereby incorporated herein by reference.
BACKGROUND
Field of the Invention
The present invention relates to an engaging pin of a fishing reel. In particular, present invention relates to an engaging pin that engages a worm shaft of a fishing reel having intersecting spiral grooves.
Background Information
A fishing reel can include a reciprocating mechanism, having a worm shaft and an engaging pin that engages the worm shaft, to wind a fishing line evenly onto a spool (for example, refer to Japanese Registered Utility Modal No. 2585219 and Japanese examined utility model application publication No. 1992-44913). An engagement portion at the distal end of a conventional engagement pin can be worn by engaging intersecting spiral grooves formed on the worm shaft. In order to prevent this wear, in Japanese Registered Utility Modal No. 2585219, metal is cut and subjected to hard surface treatment to manufacture an engagement pin. Further, in Japanese examined utility model application publication No. 1992-44913, an engaging pin is manufactured by a sintering process of ceramics.
SUMMARY
When an engagement pin engages a spiral groove, if the accuracy of the shape of the engagement portion is not sufficient, the engagement pin can rattle. Conventional engagement pins can be manufactured by cutting a metal or by a sintering process of ceramics so that the engagement pin is not easily worn. Consequently, it is difficult to accurately stabilize the shape of the engagement portion of the engagement pin.
The object of the present invention is to accurately stabilize the shape of the engagement portion of an engagement pin of a reciprocating mechanism.
The engagement pin of a fishing reel according to the present invention engages with a worm shaft of a fishing reel having intersecting spiral grooves. The engagement pin comprises a shaft portion, and an engagement portion that is integrally disposed on one end of the shaft portion and that engages the spiral grooves. At least the engagement portion is formed from synthetic resin.
In this engagement pin, at least the engagement portion, which engages the spiral grooves of the worm shaft, is made of synthetic resin that can be formed by injection molding. The shape of the engagement portion of the engagement pin of the reciprocating mechanism can be accurately stabilized by this injection molding.
The shaft portion and the engagement portion may be integrally formed of synthetic resin. In this embodiment, manufacturing the engagement pin is simple. Further, it is possible to increase the turning performance of the engagement pin around the shaft by using a synthetic resin having a high sliding performance.
The engagement pin may further comprise a constricted portion with a smaller diameter than the shaft portion, which is disposed between the shaft portion and the engagement portion. In this embodiment, the axial position of the engagement pin in a direction that approaches the worm shaft can be positioned by the level difference between the shaft portion and the constricted portion. Accordingly, it is simple to maintain the gap between the distal end of the engagement portion and the bottom portion of the spiral grooves constant.
The engagement portion can be thinner in a direction extending away from one end, and may comprise, at the distal end, an engagement recess that engages the bottom portion of the spiral grooves and which is recessed in an arcuate shape. In this embodiment, it is possible to smoothly move the engagement pin while maintaining a constant gap between the engagement recess and the bottom portion.
The shaft portion may be non-circular. In this embodiment, since the cross section that is perpendicular to the axial direction of the shaft portion is non-circular, a gap can be formed between the engagement pin, which is disposed in a circular hole, and the hole. Accordingly, when forming the engagement pin with a single split mold that is divided along the axial direction, by arranging the cleavage planes of the two molds in the portion where the gap is formed, even if burrs are generated, the accuracy of the engagement pin, which is disposed in the circular hole, will not be easily affected.
The cross section that is perpendicular to the axial direction of the shaft portion may comprise at least one flat portion. In this embodiment, since a flat portion is a simple shape, it is simple to form a portion which becomes the flat portion in the dividing portion of the mold.
The shaft portion may comprise a first flat surface that is disposed along the axial direction. In this embodiment, since a first flat surface is an even simpler shape, it is simple to forma portion which becomes the first flat surface in the dividing portion of the mold.
The shaft portion may further comprise a second flat surface that is parallel to the first flat surface. In this embodiment, by disposing portions that become the first flat surface and the second flat surface in the dividing portion of the mold, when manufacturing an engagement pin, the engagement pin is less likely to be affected by burrs that may be generated in the dividing portion.
The reciprocating mechanism of a fishing reel according to another aspect of the present invention comprises a worm shaft of a fishing reel, a rotary drive mechanism, and the above-described engagement pin. The worm shaft comprises intersecting spiral grooves. The rotary drive mechanism rotationally drives the worm shaft. The engagement pin engages the spiral grooves and reciprocates along the axial direction of the worm shaft with the rotation of the worm shaft.
In this reciprocating mechanism, when the worm shaft is rotated by the rotary drive mechanism, the engaging pin that engages the spiral grooves reciprocates along the axial direction of the worm shaft. Since at leak the engagement portion of this engagement pin, which engages the spiral grooves, is made of synthetic resin, the above action and effect are exerted.
According to the present invention, it is possible to accurately stabilize the shape of the engagement portion of an engagement pin of a reciprocating mechanism.



BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the attached drawings which form a part of this original disclosure.
FIG. 1 is a perspective view of a dual-bearing reel, which is a fishing reel employing a first embodiment of the present invention;
FIG. 2 is a cross-sectional view of the dual bearing reel;
FIG. 3 is a cross-sectional view of a level winding mechanism;
FIG. 4 is a perspective view of the level winding mechanism;
FIG. 5A is a side view of the engagement pin, and FIG. 5B is a cross-sectional view of the engagement pin of FIG. 5A taken along line X-X;
FIG. 6 is a plan view of the engagement pin;
FIG. 7A is a cross-sectional view of a torque limiting device, and FIG. 7B is an enlarged view of the locking recess in FIG. 7A;
FIG. 8 is an enlarged cross-sectional view of the torque limiting device;
FIG. 9 is a lateral cross-sectional view of a spinning reel, which is a fishing reel employing a second embodiment of the present invention;
FIG. 10 is a cross-sectional view of an oscillating mechanism; and
FIG. 11 is an exploded perspective view of the oscillating mechanism.



DETAILED DESCRIPTION OF THE EMBODIMENTS
First Embodiment
The engagement pin and the reciprocating mechanism of the fishing reel according to the first embodiment of the present invention will be described below, with reference to the drawings, In the first embodiment, the fishing reel is a dual-bearing reel 100. In the following description, “front” indicates the direction in which the fishing line is cast (unreeled); specifically, the upward direction in FIG. 2 and the left direction in FIG. 9 are the “front.”
Schematic Structure of the Dual-Bearing Reel
As shown in FIG. 1 and FIG. 2, the dual-bearing reel 100 employing the first embodiment of the present invention unreels a fishing line forward (the upper-left direction in FIG. 1). The dual-bearing reel 100 comprises a reel body 1 to which is rotatably provided a handle 2, a rotary drive mechanism 3, a spool 4, and a level winding mechanism 50 (one example of a reciprocating mechanism).
As shown in FIG. 1, the reel body 1 comprises a first side plate 11, a second side plate 12, a plurality of connecting portions 13, and a mounting portion 14. The first side plate 11 and the second side plate 12 are opposed to each other. As shown in FIG. 2, a spool shaft 41 is supported by the first side plate 11 and the second side plate 12.
As shown in FIG. 1, the connecting portions 13 connect the first side plate 11 and the second side plate 12. The mounting portion 14 extends in the longitudinal direction, and is configured to be mounted to a fishing rod. Of the connecting portions 13, at least one connecting portion 13 is fixed to the mounting portion 14.
As shown in FIG. 2, the handle 2 is rotatably mounted to the outside surface of the first side plate 11. The spool 4 and the level winding mechanism 50 are driven via the rotary drive mechanism 3, by rotating the handle 2.
The rotary drive mechanism 3 is a mechanism for transmitting the rotation of the handle 2 to the spool 4 and the level winding mechanism 50. The rotary drive mechanism 3 is installed or disposed in the first side plate 11. The rotary drive mechanism 3 comprises a drive shaft 31, a drive gear 32, a pinion gear 33, a first gear 34 and a second gear 35.
The drive shaft 31 is coupled to the handle 2, and integrally rotates with the handle 2. The rotation of the drive shaft 31 in the line delivering direction is prohibited by a one-way clutch 36. The drive gear 32 is rotatably mounted to the drive shaft 31 and integrally rotates with the drive shaft 31 via a drag mechanism 29. The pinion gear 33 meshes with the drive gear 32. Meanwhile, the pinion gear 33 is a tubular shape. The first gear 34 is mounted to the drive shaft 31 and integrally rotates with the drive shaft 31. The second gear 35 meshes with the first gear 34.
The spool 4 is disposed between the first side plate 11 and the second side plate 12. A fishing line is would on the outer perimeter surface of the spool 4 by rotation of the handle 2. The spool 4 comprises an integrally rotatable spool shaft 41
The spool shaft 41 is rotatably supported to the first side plate 11 and the second side plate 12 via an axle bearing member. The end of the spool shaft 41 on the first side plate 11 side extends through the pinion gear 33. The spool shaft 41 engages with the pinion gear 33 via a clutch mechanism. When the clutch mechanism is put in a clutch-on state, the spool shaft 41 and the pinion gear 33 engage each other and are integrally rotatable. Further, if the clutch mechanism is in a clutch-off state, engagement between the spool shaft 41 and the pinion gear 33 is released, and the spool shaft 41 and the pinion gear 33 are relatively rotatable independently of each other. In particular, the pinion gear 33 engages the spool 41 and the engagement is released via an engagement pin 4 that extends through the spool shaft 41. The pinion gear 33 engages a clutch pin 42 when moving to the left side in FIG. 2, and the engagement with the clutch pin 42 is released when moving to the right side in FIG. 2.
Configuration of the Level Winding Mechanism
In FIGS. 2-4, the level winding mechanism 50 is a mechanism that reciprocates to evenly wind the fishing line on the spool 4. The level winding mechanism 50 comprises a worm shaft 5, a guide member 6, an engagement pin 7, a fishing line guide 8, a lid member 9, and a torque limiting mechanism 10.
Worm shaft
As shown in FIG. 2, the worm shaft 5 is formed in a cylindrical shape and comprises intersecting spiral grooves 5a on the outer perimeter surface. The worm shaft 5 is disposed substantially parallel to the spool shaft 41. The worm shaft 5 extends between the first side plate 11 and the second side plate 12.
A first end portion 5b of the worm shaft 5 is rotatably supported by the first side plate 11. The first end portion 5b of the worm shaft 5 can be supported by the first side plate 11 via an axle bearing member. A second end portion 5c of the worm shaft 5 is rotatably supported by the second side plate 12. The second end portion 5c of the worm shaft 5 can be supported by the second side plate 12 via an axle bearing member.
The second gear 35 described above is mounted to the first end portion 5b of the worm shaft 5. The worm shaft 5 is integrally rotatable with the second gear 35. The worm shaft 5 rotates in conjunction with the rotation of the handle 2. In particular, when the handle 2 is rotated, the second gear 35 is rotated via the drive shaft 31 and the first gear 34; as a result, the worm shaft 5 is rotated.
Guide Member
The guide member 6 is a member for guiding the fishing line guide 8, into which a fishing line can be inserted. The guide member 6 is formed in a cylindrical shape, and is disposed on the outer perimeter side of the worm shaft 5. The guide member 6 extends substantially parallel to the worm shaft 5. Further, the guide member 6 extends between the first side plate 11 and the second side plate 12. A first end portion of the guide member 6 is non-rotatably supported by the first side plate 11. A second end portion of the guide member 6 is non-rotatably supported to the second side plate 12.
As shown in FIG. 1 and FIG. 3, the guide member 6 comprises a window portion 6a. The window portion 6a enables the engagement pin 7 to engage the spiral grooves 5a. The window portion 6a is formed along the longitudinal direction of the guide member 6. That is, the window portion 6a is formed along the worm shaft 5. The window portion 6a opens downward when using the dual-bearing reel 100.
Engagement Pin
As shown in FIG. 3, FIG. 5A, FIG. 5B and FIG. 6, the engagement pin 7 is configured to engage the spiral grooves 5a of the worm shaft 5. The engagement pin 7 extends from outside the guide member 6 to inside the guide member 6 via the window portion 6a. The engaging pin 7 comprises a shaft portion 7a, an engagement portion 7b, and a constricted portion 7c. At least the engagement portion 7b of the engagement pin 7 is formed from synthetic resin, such as polyacetal and polyamide resins. In the first embodiment, the entire engagement pin 7 including the shaft portion 7a is formed from synthetic resin. As shown by the X-X cross section in FIG. 5B, the cross section 7d of the shaft portion 7a which is perpendicular to the axial direction is non-circular. The cross section 7d comprises at least one flat portion 7e. The flat portion 7e comprises at least a first flat surface 7f that is disposed along the axial direction. In the first embodiment, the flat portion 7e comprises a first flat surface 7f, and a second flat surface 7g which is parallel to the first flat surface 7f. 
When manufacturing an engagement pin 7 with a single split mold which is divided in the axial direction, a first flat surface 7f and a second flat surface 7g are disposed in the dividing portion of the mold. Thus, burrs are less likely to be generated in the dividing portion of the mold, and, even if generated, the burrs are less likely to contact the inner perimeter surface of a pin mounting portion 9b of the lid member 9 described below. Accordingly, the level winding mechanism 50 is less likely to be affected by burrs.
The engagement portion 7b is integrally and rotatably disposed on one end of the shaft portion 7a, The engagement portion 7b is configured to engage with the spiral grooves 5a. The shaft portion 7a and the engagement portion 7b are integrally formed, The engagement portion 7b is thinner in a direction away from one end of the shaft portion 7a, and may comprise, at the distal end, an engagement recess 7h that engages with the bottom portion 5d of the spiral grooves 5a and which is recessed in an arcuate shape.
Fishing Line Guide
As shown in FIG. 3 and FIG. 4, the fishing line guide 8 slides along the worm shaft 5. In particular, the fishing line guide 8 reciprocates along the worm shaft 5. The fishing line guide 8 is guided by the guide member 6. The fishing line guide 8 comprises a first through-hole 8a and a second through-hole 8b. 
The first through-hole 8a is a hole for turnably housing the shaft portion 7a of the engagement pin 7. The cross-section of the first through-hole 8a is formed in a circular shape. A female threaded portion 8c is formed in at least one portion of the inner perimeter surface of the first through-hole 8a. The first through-hole 8a communicates with the second through-hole 8b. 
The second through-hole 8b extends along the worm shaft 5. The guide member 6 extends through the second through-hole 8b. The inner perimeter surface of the second through-hole 8b contacts the outer perimeter surface of the guide member 6. Thus, the fishing line guide 8 is guided by the guide member 6. The cross-section of the second through-hole 8b is formed in a circular shape.
The fishing line guide 8 comprises a fishing line guide portion 8d for guiding the fishing line. The fishing line extends forward from the spool 4 through the fishing line guide portion 8d. Meanwhile, the fishing line guide portion 8d is a hole that extends through the fishing line guide 8, and is formed in a vertically long shape.
Lid Member
As shown in FIG. 3, the lid member 9 comprises a lid side plate 9a and a pin mounting portion 9b. The lid side plate 9a is configured to cover one end of the first through-hole 8a. The pin mounting portion 9b is formed in a cylindrical shape, and extends from the lid side plate 9a. The pin mounting portion 9b is housed inside the first through-hole 8a. Further, the pin mounting portion 9b is disposed between the inner perimeter surface of the first through-hole 8a. and the outer perimeter surface of the engagement pin 7. In particular, the pin mounting portion 9b is disposed between the inner perimeter surface of the first through-hole 8a and the outer perimeter surface of the shaft portion 7a. The pin mounting portion 9b rotatably houses the engagement pin 7.
The shaft portion 7a of the engagement pin 7 is housed in the pin mounting portion 9b. The inner diameter of the pin mounting portion 9b is designed to be about the same dimension as the outer diameter of the shaft portion 7a of the engagement pin 7. In particular, the outer diameter of the shaft portion 7a is smaller than the inner diameter of the pin mounting portion 9b to the degree that the shaft portion 7a of the engagement pin 7 is turnable around the axis inside the pin mounting portion 92.
A male threaded portion 9c is formed in at least one portion of the outer perimeter surface of the pin mounting portion 9b. The male threaded portion 9c is screwed to a female threaded portion 8c that is formed on the inner perimeter surface of the first through-hole 8a. That is, the pin mounting portion 9b is fixed to the fishing line guide 8, and holds the engagement pin 7. As can be seen from FIG. 3, the outside surface of the lid member 9 is smoothly continuous with the outside surface of the fishing line guide 8.
Torque Limiting Mechanism
As shown in FIG. 2, the torque limiting mechanism 10 is disposed between the rotary drive mechanism 3 and the worm shaft 5. The torque limiting mechanism 10 limits the rotational torque that is transmitted from the rotary drive mechanism 3 to the worm shaft 5. In other words, the torque limiting mechanism 10 limits the rotational drive force that rotates the worm shaft 5. In the present embodiment, the torque limiting mechanism 10 is disposed between the drive shaft 31 and the first gear 34. As shown in FIG. 7A and FIG. 8, the torque limiting mechanism 10 comprises a pair of pin members 51 and a biasing member 52 disposed on the drive shaft 31 and at least one locking recess 53 that is formed on the first gear 34. The biasing member 52 is, for example, a coil spring, which biases the pair of pin members 51 toward the first gear 34. The locking recess 53 is formed on the inner perimeter surface of the first gear 34. In this embodiment, four locking recesses 53 are disposed at intervals in the circumferential direction.
A through-hole 31a, to which the pin members 51 can be mounted freely movable back and forth, is formed on the drive shaft 31, extending through in the diameter direction. The pin member 51 comprises a head 51a having a hemispherical shell shaped curved surface, and a shaft portion 51b which is smaller in diameter than the head 51a. The pin member 51 is disposed in the through-hole 31a so that the head 51a is oriented toward the locking recess 53. The biasing member 52 is disposed on the outer perimeter sides of the shaft portions 51b of the pair of pin members 51, and is disposed in a compressed state between the pair of heads 51a. As shown enlarged in FIG. 7B, the locking recess 53 comprises a linear slope 53a on the downstream side of the rotation direction of the first gear 34 in the line winding direction indicated by the arrow R, and comprises a cylindrical surface 53b on the upstream side of the rotation direction. Therefore, normally, the rotation of the drive shaft 31 is transmitted to the first gear 28 with the pin member 51 applying pressure to the slope 53a. Thus, if a foreign object is caught in the level winding mechanism 15, and the handle 2 is turned hard applying excessive force on the first gear 28, the pin member 51 retracts into the through-hole 31a and the drive shaft 31 idles; therefore, the first gear 28 is less likely to be damaged. The contact surface (slope 53a and cylindrical surface 53b) of the locking recess 53 which contacts the head 51a comprises an inclined surface 53c that intersects the axis of the drive shaft 31, as shown in FIG. 8. The inclined surface 53c is inclined so as to gradually approach the axis of the drive shaft 31 toward the drive gear 32 side. When manufacturing the first gear 34 by molding, the inclined surface 53c may be configured using a draft taper of the mold. Thus, when the pin member 51 applies pressure to the first gear 34, a force that presses the first gear 34 is generated in the abutting portion 31b, therefore the first gear 34 is less likely to rattle during rotation.
Operation of the Level Winding Mechanism
Next, the operation of the level winding mechanism 50 configured as described above will be explained.
If the handle 2 is rotated, the worm shaft 5 is rotated via the drive shaft 31, the first gear 34, and the second gear 35. The engagement pin 7 is reciprocated along the worm shaft 5 by the rotation of this worm shaft 5. The engagement pin 7 is turnably held by the lid member 9 and the lid member 9 is fixed to the fishing line guide 8; therefore, the fishing line guide 8 is also reciprocated along the worm shaft 5 with the engagement pin 7. As a result, the fishing line, which is guided by the fishing line guide portion 83 of the fishing line guide 8, is evenly wound on the spool 4.
Since the engagement portion 7b is formed from synthetic resin, the shape of the engagement portion 7b can be accurately stabilized, when the engagement portion 7b of the engagement pin 7 slides into the spiral grooves 5a of the worm shaft 5. Further, since a torque limiting mechanism 10 is disposed between the rotary drive mechanism 3 and the worm shaft 5, the shearing force that acts on the engagement portion 7b can be limited, and longevity of the engagement pin 7 can be achieved.
Second Embodiment
In the second embodiment, the fishing reel is a spinning reel 200, as shown in FIG. 9. The spinning reel 200 employing the second embodiment of the present invention casts a fishing line in a forward direction. The spinning reel 200 comprises a reel body 101. The reel body has a handle 102, a rotary drive mechanism 103, a spool 104 having a spool shaft 141, a rotor 130, and an oscillating mechanism 150 (one example of a reciprocating mechanism) rotatably provided thereto.
Schematic Configuration of the Spinning Reel
The reel body 101 rotatably supports the handle 102 and the rotor 130. Further, the reel body 101 supports the spool 104, which is capable of being reciprocally moved back and forth. The handle 102 is rotatably supported around the axis in the lateral direction. The rotary drive mechanism 103 transmits the rotation of the handle 102 to the rotor 130 and the oscillating mechanism 150. The rotary drive mechanism 103 comprises a drive shaft 131 that is integrally and rotatably coupled to the handle 102, a drive gear 132, and a pinion gear 133. The drive gear 132 comprises face gear teeth, and is integrally rotated around a lateral axis with the drive shaft 131. The pinion gear 133 is a tubular gear, which meshes with the drive gear 132. A spool shaft 141 extends through the inner perimeter part of the pinion gear 133. The rotor 130 is integrally and rotatably coupled to the pinion gear 133. The rotor 130 winds the fishing line onto the spool 104 by rotating around the spool 104.
The spool 104 is disposed to the front portion of the rotor 130. The fishing line is wound around the outer perimeter of the spool 104 by the rotor 130 as the spool moves back and forth with the spool shaft 141. The spool shaft 141 is disposed extending through the center of the pinion gear 133, and a spool 104 is coupled to the distal end thereof. The spool shaft 141 is reciprocated back and forth inside the pinion gear 133 by an oscillating mechanism 150 that is coupled to the proximal end.
Configuration of the Oscillating Mechanism
The oscillating mechanism 150 reciprocates the spool 104 in the longitudinal direction with the rotation of the handle 102, via the spool shaft 141. The oscillating mechanism 150 evenly winds the fishing line on the spool 104. As shown in FIG. 10 and FIG. 11, the oscillating mechanism 150 comprises a worm shaft 105, an engagement pin 107, a slider 156, a torque limiting mechanism 110 (refer to FIG. 11), an intermediate gear 160, and a pair of guide shafts 162a, 162b. An engaging pin 107 is turnably housed in the slider 156, as will be described below. (refer to FIG. 10).
Worm Shaft
The worm shaft 105 rotates in conjunction with a winding operation of the handle 102, which is mounted on the reel body 101. As shown in FIG. 10 and FIG. 11, the worm shaft 105 is disposed parallel to the spool shaft 141 below the spool shaft 141. The worm shaft 105 is disposed along the longitudinal direction. The two ends of the worm shaft 105 are rotatably supported on the reel body 101 via, for example, a rolling bearing. Further, the worm shaft 105 comprises intersecting spiral grooves 105a on the outer perimeter surface. A large diameter connecting portion 105g, to which an intermediate gear 160 is connected, is formed at the distal end of the worm shaft 105.
Engagement Pin
As shown in FIG. 10, in the engagement pin 107 of the second embodiment, the shaft portion 107a is formed from metal, but the engagement portion 107b and the constricted portion 107c are made of synthetic resin. Therefore, the cross section of the shaft portion 107a is circular. A fitting recess 107e, which is fitted to the constricted portion 107c, is formed at one end of the shaft portion 107a on the engagement portion 17b side. A circular projection 107f, which is fitted to a stopper member 158, is formed at the other end of the shaft portion 107a. A fitting protrusion 107g, which is fixed to the fitting recess 107e, is formed in the constricted portion 107c. The fitting protrusion 107g may be fixed by bonding to the fitting recess 107e, or may be fixed by insert molding.
Slider
The slider 156 moves in the longitudinal direction along the worm shaft 105. As shown in FIG. 3, the slider 156 comprises a slider body 156a that turnably houses the engagement pin 107, and a stopper member 158 that retains the engagement pin 107. The slider body 156a comprises a spool shaft connecting portion 156b, an engagement pin mounting portion 156c, and a pair of guide portions 156d. Also provided is a stopper member 158 for retaining the engagement pin 107.
The rear end portion of the spool shaft 141 is non screwed to the spool shaft connecting portion 156b. The engagement pin 107 is turnably mounted to the engagement pin mounting portion 156c. A pair of guide shafts 162a, 162b, which guide the slider body 156a in the longitudinal direction, are fitted to the pair of guide portions 156d. The stopper member 158 is screwed to the slider body 156a. 
As shown in FIG. 10 and FIG. 11, the engaging member mounting portion 156c is a substantially tubular portion. The shaft portion 107a of the engagement pin 107 is turnably mounted to the engagement pin mounting portion 156c. When the engagement pin 107 is mounted to the engagement pin mounting portion 156c, the movement thereof is regulated in the axial direction.
Intermediate Gear
As shown in FIG. 11, the intermediate gear 160 is coupled to the distal end of the worm shaft 105 via a torque limiting mechanism 110. The intermediate gear 160 meshes with the pinion gear 133. The intermediate gear 23 is integrally and rotatably mounted to the front end of the worm shaft 105 by a non-circular engagement. The rotation of the handle 102 is transmitted to the intermediate gear 160 via the drive gear 132 and the pinion gear 133.
Torque Limiting Mechanism
As shown in FIG. 11, the torque limiting mechanism 110 limits the rotational torque that is transmitted from the rotary drive mechanism 103 to the worm shaft 105. In other words, the torque limiting mechanism 110 limits the rotational drive force which rotates the worm shaft 105. In the second embodiment, the torque limiting mechanism 110 is disposed between the intermediate gear 160 and the worm shaft 105. The torque limiting mechanism 110 basically has the same configuration as the torque limiting mechanism 10 of the dual-bearing reel 100 shown in FIG. 7A and FIG. 8. As shown in FIG. 11, the torque limiting mechanism 110 comprises a pair of pin members 151 and a biasing member 152 disposed in the connecting portion 105g of the worm shaft 105, and at least one locking recess 153 that is formed on the intermediate gear 160, The biasing member 152 is, for example, a coil spring, which biases the pair of pin members 151 toward the intermediate gear 160. The locking recess 153 is formed on the inner perimeter surface of the intermediate gear 160. In this embodiment, four locking recesses 153 are disposed at intervals in the circumferential direction. The configuration of the torque limiting mechanism 110 is the same as the first embodiment, and the description thereof is omitted.
Operation of the Oscillating Mechanism
Next, the operation of the oscillating mechanism 150 configured as described above will be explained.
If the handle 102 is rotated, the worm shaft 105 is rotated via the drive shaft 131, the pinion gear 133, and the intermediate gear 160. The engagement pin 107 is reciprocated along the worm shaft 105 by the rotation of the worm shaft 105. The engagement pin 107 is turnably held by the slider 156, and the slider 156 is fixed to the spool shaft 141; therefore, the spool 104 is reciprocated along the worm shaft 105 with the engagement pin 107. As a result, the spool 104 is reciprocated back and forth with respect to the rotor 130, and the fishing line which is guided by the spool 104 is evenly wound on the spool 104.
Since the engagement portion 107b is formed from synthetic resin, the shape of the engagement portion 107b can be accurately stabilized, when the engagement portion 107b of this engagement pin 107 slides into the spiral grooves 105a of the worm shaft 105. Further, since a torque limiting mechanism 110 is disposed between the worm shaft 105 and the intermediate gear 160, which is mounted to the worm shaft 105, the shearing force that acts on the engagement portion 107b can be limited, and longevity of the engagement pin 107 can be achieved.
Characteristics
The embodiment described above can be expressed as the following.
(A) An engagement pin 7 (or 107) of a dual-bearing reel 100 (or a spinning reel 200) engages a worm shaft 5 (or 105) of a fishing reel having intersecting spiral grooves 5a (or 105a), The engagement pin 7 (or 107) comprises a shaft portion 7a (or 107a), and an engagement portion 7b (or 107b) that is integrally and turnably disposed on one end of the shaft portion 7a (or 107a) and that engages the spiral grooves 5a (or 105a). At least the engagement portion 7b (or 107b) is formed from synthetic resin.
In the engagement pin 7 (or 107), at least the engagement portion 7b (or 107b), which engages the spiral grooves 5a (or 105a) of the worm shaft 5 (or 105), is made of synthetic resin that can be formed by injection molding. The shape of the engagement portion 7b (or 107b) of the engagement pin 7 (or 107) can be accurately stabilized by the injection molding.
(B) The shaft portion 7a (or 107a) and the engagement portion 7b (107b) may be made of synthetic resin that is integrally formed. In this embodiment, manufacturing the engagement pin 7 (or 107) is simple. Further, it is possible to increase the turning performance of the engagement pin 7 (or 107) around the shaft, by using a synthetic resin with high sliding performance.
(C) The engagement pin 7 (or 107) may further comprise a constricted portion 7c (or 107c) with a smaller diameter than the shaft portion 7a (or 107a), which is disposed between the shaft portion 7a (or 107a) and the engagement portion 7b (or 107b). In this embodiment, the axial position of the engagement pin 7 (or 107) in a direction that approaches the worm shaft 5 (or 105) can be positioned by the level difference between the shaft portion 7a (or 107a) and the constricted portion 7c (or 107c). Accordingly, maintaining the gap between the distal end of the engagement portion 7b (or 107b) and the bottom portion of the spiral grooves 5a (or 105a) constant is simple.
(D) The engagement portion 7b (or 107b) is thinner in a direction extending away from one end, and may comprise, at the distal end, an engagement recess 7h (or 107h) that engages the bottom portion of the spiral grooves 5a (or 105a) and which is recessed in an arcuate shape. In this embodiment, it is possible to smoothly move the engagement pin 7 (or 107) while maintaining the gap between the engagement recess 7h (or 107h) and the bottom portion constant.
(E) The cross section of the shaft portion 7a is non-circular. In this case, since the cross section 7d that is perpendicular to the axial direction of the shaft portion 7a is non-circular, a gap can be formed between the engagement pin 7, which is disposed in a circular hole, and the mounting portion of the engagement pin 7. Accordingly, when forming with a single split mold that is divided along the axial direction, by arranging the cleavage planes of the two molds in the portion where the gap is formed, even if burrs are generated, the accuracy of the engagement pin, which is disposed in the circular hole, will not be easily affected.
(F) The cross section 7d that is perpendicular to the axial direction of the shaft portion 7a comprises at least one flat portion 7e. In this case, since a flat portion 7e is a simple shape, it is simple to form a portion which becomes the flat portion 7e in the dividing portion of the mold.
(G) The shaft portion 7a comprises a first flat surface 7f that is disposed along the axial direction. In this embodiment, since a first flat surface 7f is an even simpler shape, it is simple to form a portion which becomes the first flat surface 7f in the dividing portion of the mold.
(H) The shaft portion 7a may further comprise a second flat surface 7g that is parallel to the first flat surface 7f. In this case, by disposing portions that become the first flat surface 7f and the second flat surface 7g in the dividing portion of the mold, when manufacturing an engagement pin 7, the engagement pin is less likely to be affected by burrs that may be generated in the dividing portion.
(I) The level winding mechanism 50 (or the oscillating mechanism 150) of the dual-bearing reel 100 (or the spinning reel 200) comprises a worm shaft 5 (or 105) of the dual-bearing reel 100 (or the spinning reel 200), a rotary drive mechanism 3 (or 103), and an engaging pin 7 (or 107) described above. The worm shaft 5 (or 105) comprises intersecting spiral grooves 5a (or 105a). The rotary drive mechanism 3 (or 103) rotationally drives the worm shaft 5 (or 105). The engagement pin 7 (or 107) engages with the spiral grooves 5a (or 105a) and is reciprocated along the axial direction of the worm shaft 5 (or 105) with the rotation of the worm shaft 5 (or 105).
In this level winding mechanism 50 (or oscillating mechanism 150), when the worm shaft 5 (or 105) is rotated by the rotary drive mechanism 3 (or 103), the engaging pin 7 (or 107) that is engaged with the spiral grooves 5a (or 105a) is reciprocated along the axial direction of the worm shaft 5 (or 105). Since at least the engagement portion 7b (or 107b) of this engagement pin 7 (or 107), which engages with the spiral grooves 5a (or 105a), is formed from synthetic resin, the above action and effect are exerted.
Other Embodiments
One embodiment of the present invention was described above, but the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. Especially, the various embodiments and modified examples described in the present Specification can be freely combined according to necessity.
(A) In the above-described embodiment, the present invention was described using an engagement pin 7 (or 107) and a level winding mechanism 50 (or oscillating mechanism 150) used in a dual-bearing reel 100 and a spinning reel 200, as examples; however, the present invention may be applied to other engagement pins and reciprocating mechanisms of a fishing reel, such as an electric reel.
(B) In the first embodiment, the present invention was described using a level winding mechanism 50, which is operated only by rotation in the line winding direction of the handle 2 in a dual-bearing reel 100; however, the present invention is not limited thereto. The present invention may be applied to a level winding mechanism that is operated in conjunction with the rotation of the spool. In this case, the torque limiting mechanism may be disposed between the spool and the worm shaft.

## Claims

1. An engagement pin for engaging a worm shaft of a fishing reel, the worm shaft having intersecting spiral grooves, the engagement pin comprising:
a shaft portion having an end; and
a synthetic engagement portion integrally disposed on the end of the shaft portion and configured to engage the intersecting spiral grooves,
at least the engagement portion being formed from synthetic resin.

2. The engagement pin of the fishing reel recited in claim 1, wherein
the shaft portion and the engagement portion are integrally formed from synthetic resin.

3. The engagement pin of the fishing reel recited in claim 1, further comprising:
a constricted portion having a diameter smaller than a diameter of the shaft portion, and being disposed between the shaft portion and the engagement portion.

4. The engagement pin of the fishing reel recited in claim 1, wherein
the engagement portion thins in a direction away from the end of the shaft portion, and comprises at a distal end, an engagement recess configured to engage a bottom portion of the intersecting spiral grooves and being recessed in an arcuate shape.

5. The engagement pin of the fishing reel recited in claim 1, wherein
a cross sectional area of the shaft portion that is perpendicular to an axial direction of the shaft portion is non-circular.

6. The engagement pin of the fishing reel recited in claim 5, wherein
the cross sectional area of the shaft portion comprises at least one flat portion.

7. The engagement pin of the fishing reel recited in claim 1, wherein
the shaft portion comprises a first flat surface disposed along an axial direction of the shaft portion.

8. The engagement pin of the fishing reel recited in claim 7, wherein
the shaft portion further comprises a second flat surface that is parallel to the first fiat surface.

9. A reciprocating mechanism of a fishing reel, comprising:
a worm shaft having intersecting spiral grooves;
a rotary drive mechanism configured to rotationally driving the worm shaft; and
an engagement pin comprising a shaft portion having an end, and an engagement portion integrally disposed on the end of the shaft portion and configured to engage the intersecting spiral grooves, the engagement pin being configured to be reciprocated along an axial direction of the worm shaft, at least the engagement portion being formed from synthetic resin.