JP2016054950A - Ratchet manufacturing method of reclining device, reclining device and ratchet manufacturing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ratchet manufacturing method of a reclining device, a reclining device and a ratchet manufacturing apparatus, in which a sag amount of an internal tooth of a ratchet is reduced, and miniaturization, weight reduction and cost reduction of the reclining device can be achieved.SOLUTION: A ratchet manufacturing method is characterized as follows: a tooth profile for forming an internal tooth 23 is formed by half blanking in an outer circumferential surface; a tooth tip forming part for forming a tooth tip side of the internal tooth 23, a tooth bottom forming part for forming a bottom side of the internal tooth, and a slope where the diameter of the tooth tip forming part and the tooth bottom forming part is gradually reduced as approaching the distal surface are formed in the tooth profile of a corner of a distal surface in the push up direction; and a ratchet 21 is manufactured by using a punch with tilt angles different from the slope of the tooth tip forming part and the slope of the tooth bottom forming part.SELECTED DRAWING: Figure 2

Description

  The present invention provides a ratchet manufacturing method for a bottomed cylindrical reclining device in which inner teeth are formed along the circumferential direction on the inner cylindrical surface, and one surface is an open surface, a reclining device using the ratchet, and the above The present invention relates to a ratchet manufacturing apparatus.

  As an example of a reclining device that adjusts the angle of the seat back of the seat, a base plate fixed to the seat cushion side, fixed to the seat back side, provided rotatably with respect to the base plate, and circumferentially on the inner cylinder surface A ratchet formed with internal teeth along the surface, and a pole having outer teeth that are movable on the surface of the base plate facing the ratchet in a radial direction of the central axis of rotation of the ratchet and can mesh with the internal teeth of the ratchet. In some cases, the outer teeth of the pole and the inner teeth of the ratchet are engaged (locked) / unengaged (unlocked) to prohibit / permit tilting of the seat back with respect to the seat cushion.

  As shown in FIGS. 14 and 15, the ratchet has a bottomed cylinder in which a recess A is formed at the center, an inner tooth B is formed on the inner peripheral surface of the recess A, and an outer tooth D is formed on the outer peripheral surface. It has become a shape.

  This ratchet C is manufactured by half-cutting (pressing) a plate material using a mold shown in FIG.

  In the figure, the mold 1001 abuts on the peripheral surface of the ratchet C when the ratchet C is formed from a plate material. The molds 1003 and 1004 hold the outer edge portion of the ratchet C.

  The molds 1005 and 1006 form the first recess A ′ of the ratchet C and prohibit the engagement of the inner teeth B, the outer teeth of the pole and the inner teeth B of the ratchet C on the inner peripheral surface of the first recess A ′. Pole guides (toppings) 501 and 505 are formed. The molds 1007 and 1008 form a second recess A ″. The molds 1009 and 1010 form a hole D (see, for example, Patent Document 1).

JP 2004-049465 A

  However, in the mold 1005 that forms the inner teeth B, the tip surface in the pushing direction of the mold 1005 (the arrow direction in the figure) is a flat surface, and the corners of the tip surface and the peripheral surface are at right angles. Therefore, when the internal teeth B are formed by half-punching using the mold 1005, as shown in FIG. 17, the corner F of the internal teeth B is rounded.

  When the length 1 of the droop F in the tooth width direction (hereinafter referred to as the droop amount) becomes long, the meshing length of the pole with the external teeth becomes short, and the locking force of the reclining device decreases. For this reason, in order to ensure appropriate meshing length, the tooth width of the internal tooth B will be lengthened, and a reclining apparatus will enlarge.

  An object of the present invention is to provide a ratchet manufacturing method, a reclining device, and a ratchet manufacturing device for a reclining device that can reduce the amount of internal teeth of the ratchet and reduce the size, weight, and cost of the reclining device.

  In order to achieve at least one of the above-described problems, a ratchet manufacturing method reflecting one aspect of the present invention has inner teeth formed along the circumferential direction on the inner cylinder surface, and one surface is an open surface. In the ratchet manufacturing method for the bottomed cylindrical reclining device, a tooth profile that forms the internal teeth is formed on the outer peripheral surface by half-punching, and the tooth profile is a tooth tip that forms the tooth tip side of the internal tooth A tooth forming portion that forms the tooth bottom side of the inner tooth, and an end portion of the outer peripheral surface in the pushing direction of the tooth profile is a tooth tip forming portion and a tooth bottom forming portion as approaching the tip surface The ratchet is manufactured using a punch in which a slope having a gradually decreasing diameter is formed, and the slope of the tooth tip forming portion and the slope of the tooth bottom forming portion are different in inclination angle.

  Further, a reclining device reflecting one aspect of the present invention is a reclining device having a bottomed cylindrical ratchet in which inner teeth are formed along the circumferential direction on the inner cylindrical surface and one surface is an open surface. , Both the tooth tip side of the internal tooth on the bottom side of the ratchet and the tooth bottom side of the internal tooth, the tooth tip circle, the tooth tip side slope, the tooth bottom, the diameter of the tooth base circle gradually decreases as approaching the bottom A side slope is formed, and the inclination angle of the tip side slope and the root side slope is different.

  Further, a ratchet manufacturing apparatus for a reclining device reflecting one aspect of the present invention includes a bottomed cylindrical ratchet in which inner teeth are formed along the circumferential direction on the inner cylinder surface and one surface is an open surface. In a ratchet manufacturing apparatus for a reclining device to be manufactured, the punch has a punch for half-cutting a plate material, and the punch has a tooth profile that forms the inner teeth by a half-cutting process on the outer peripheral surface, The tooth profile of the corner includes a tooth tip forming part that forms the tooth tip side of the internal tooth, and a tooth root forming part that forms the tooth bottom side of the internal tooth. A slope whose diameter of the circle gradually increases is formed, and the slope of the tooth tip forming part and the slope of the tooth bottom forming part have different inclination angles.

  Other features of the present invention will become more apparent from the following detailed description and accompanying drawings.

  According to the ratchet manufacturing method of the present invention, a tooth profile that forms the inner teeth is formed on the outer peripheral surface by half-punching, and the tooth profile includes a tooth tip forming portion that forms the tooth tip side of the inner teeth, and the inner teeth. It consists of a root forming part that forms the root side of the tooth, and the diameter of the tip circle and the root circle gradually increases toward the tip surface at the end of the outer peripheral surface in the pushing direction of the tooth profile. When the inner teeth are formed by manufacturing the ratchet using a punch having a different inclination angle between the inclined surface of the tooth tip forming portion and the inclined surface of the tooth bottom forming portion. Moves sufficiently and the amount of sag of the inner teeth of the ratchet is reduced.

  According to the reclining device of the present invention, the diameters of the tip circle and the root circle gradually become smaller toward the bottom on both the tooth tip side of the inner tooth and the tooth bottom side of the inner tooth on the bottom side of the ratchet. The tooth tip side slope and the root side slope are formed, and the inclination angle of the tooth tip side slope and the tooth bottom side slope is different. The amount of sag of the inner teeth of the ratchet is reduced.

  According to the ratchet manufacturing apparatus of the reclining device of the present invention, the punch has a punch for half-punching a plate material, and the punch has a tooth profile that forms the inner teeth by half-punching on the outer peripheral surface. The tooth tip forming part forming the tooth tip side of the internal tooth, and the tooth bottom forming part forming the tooth bottom side of the internal tooth, and the tip of the outer peripheral surface in the pushing direction of the tooth profile is at the tip An inclined surface in which the diameters of the tooth tip circle and the root circle gradually increase as the surface is approached is formed, and the slope of the tooth tip forming portion and the slope of the tooth bottom forming portion are different in inclination angle. Is formed, the meat moves sufficiently and the amount of sag of the inner teeth of the ratchet is reduced.

  Other effects of the present invention will become more apparent from the following detailed description and accompanying drawings.

FIG. 3 is a view taken in the direction of an arrow I in FIG. 2. It is a disassembled perspective view of the reclining apparatus of embodiment. It is a figure which shows the end surface in the cutting line III-III of FIG. FIG. 4 is a diagram illustrating an end surface taken along a cutting line IV-IV in FIG. 3. It is a figure which shows the end surface in the cutting line VV of FIG. It is a figure which shows the end surface in the cutting | disconnection line VI-VI of FIG. It is a figure which shows the end surface in the cutting line VII-VII of FIG. It is a figure which shows the end surface in the cutting line VIII-VIII of FIG. It is sectional drawing which shows the process of the state set to the metal mold | die which performs external punching and formation of an internal gear by manufacture of a ratchet. It is sectional drawing which shows the process of performing an outline stamping by manufacture of a ratchet. It is sectional drawing which shows the process of forming an internal gear by manufacture of a ratchet. It is a figure explaining the front-end | tip part (XII part) of the pushing direction of the gear extrusion punch of FIG. It is a figure which shows the relationship between the front-end | tip angle of a punch, and a fracture occurrence rate. It is a perspective view of the ratchet of a reclining device. It is sectional drawing of the cutting line XV-XV of FIG. It is a figure explaining the manufacturing method of the ratchet of FIG. It is a figure explaining the sagging of an internal tooth.

  Initially, the whole structure of the reclining apparatus of this embodiment is demonstrated using FIGS. 1-8.

  1 is a view taken in the direction of the arrow I in FIG. 2, FIG. 2 is an exploded perspective view of the reclining device according to the embodiment, FIG. 3 is a diagram showing an end surface taken along the section line III-III in FIG. FIG. 5 is a diagram showing an end surface at line IV-IV, FIG. 5 is a diagram showing an end surface at section line V-V in FIG. 3, FIG. 6 is a diagram showing an end surface at section line VI-VI in FIG. FIG. 8 is a diagram showing an end surface taken along a cutting line VII-VII in FIG. 2, and FIG. 8 is a diagram showing an end surface taken along a cutting line VIII-VIII in FIG.

  In these drawings, a ratchet 21 provided on the seat back side has a bottomed cylindrical shape in which a plate material is half-punched and one surface is an open surface. Inner teeth 23 are formed on the inner cylindrical surface of the ratchet 21 along the entire circumferential direction. A through hole 21b is formed at the center of the bottom 21a.

  Further, as shown in FIGS. 7 and 8, the diameters of the tip circle and the root circle of the inner tooth 23 on the bottom side of the ratchet 21 and the root 23 b side of the inner tooth 23 are closer to the bottom. The tip side inclined surface 23c and the tooth bottom side inclined surface 23d are gradually reduced.

  In the present embodiment, the addendum-side slope 23c and the root-side slope 23d are conical surfaces.

  And as shown in FIG.7 (b), the angle | corner (inclination angle of an inclined surface) which the tooth tip side inclined surface 23c and the central axis of the ratchet 21 make is the generating line of the conical surface which forms the tooth tip side inclined surface 23c, It is an angle (θ) made with the central axis of the ratchet 21. In the figure, instead of the central axis of the ratchet 21, a line indicating the tip of the internal tooth 23 parallel to the central axis of the ratchet 21 is used.

  In addition, the angle formed between the root-side inclined surface 23d and the central axis of the ratchet 21 is the angle formed between the generatrix of the conical surface forming the root-side inclined surface 23c and the central axis of the ratchet 21 (θ ′: θ ′ ≠ θ). In the figure, instead of the central axis of the ratchet 21, a line indicating the root 23b of the internal tooth 23 parallel to the central axis of the ratchet 21 is used.

  In the present embodiment, the inclination angle (θ) of the addendum-side inclined surface 23c is set to 15 ° to 45 °, and more preferably 30 ± 5 °.

  The base plate 25 provided on the seat cushion side also has a bottomed cylindrical shape in which a disk-shaped plate material is half-cut by a press and one surface is an open surface. The diameter of the bottom portion 25 a of the bottomed cylinder is set to be slightly larger than the outer diameter of the ratchet 21. The ratchet 21 is fitted into the bottom portion 25a, and the base plate 25 and the ratchet 21 can be rotated relative to each other about the axis 0. Further, a through hole 25 b is formed at the center of the base plate 25. In addition, four attachment protrusions that protrude in the opposite direction to the base plate 25 and engage with attachment holes 3a (see FIGS. 3 and 6) formed in the seat cushion side member 3 are formed on the bottom portion 21a of the ratchet 21. 21d is formed. That is, these mounting protrusions 21 d are formed on the externally exposed surface of the ratchet 21.

  And the outer peripheral part of the ratchet 21 and the outer peripheral part of the base plate 25 are clamped by the ring-shaped outer peripheral ring 27, and the ratchet 21 and the base plate 25 are not separated in the axis (O) direction of relative rotation. It is held so as to be capable of relative rotation.

  A rotating cam 31 is disposed in a space formed by the bottom portion 21 a of the ratchet 21 and the bottom portion 25 a of the base plate 25. A non-circular (oval) through hole 31 a is formed at the center of the rotating cam 31.

  One pole 33 and two poles 32 are arranged on the base plate 25 so as to be positioned on the radially outer side of the rotating cam 31. The pole 33 has external teeth 57 that can mesh with the internal teeth 23, and the pole 32 also has external teeth 58 that can mesh with the internal teeth 23.

  The bottom 25a of the base plate 25 is formed with a guide 25c that protrudes in the direction of the ratchet 21 and guides the pole 33 and the pole 32 in the radial direction of relative rotation. Therefore, the pole 33 and the pole 32 are movable in the radial direction of relative rotation. Further, two attachment projections projecting in the opposite direction to the ratchet 21 and engaging with attachment holes 1a (see FIGS. 3 and 6) formed in the seat back side member 1 on the bottom 21a of the base plate 25. 25d and one mounting projection 25e are formed. That is, these mounting projections 25 d and 25 e are formed on the externally exposed surface of the base plate (first member) 25.

  Each of the mounting projection 25d and the mounting projection 25e has a shape obtained by dividing an annular ring with different radii, and the mounting projection 25e has a corner portion between an inner circular arc and a radius, which will be described later. A stopper surface 25h and a second stopper surface 25i are formed.

  A cam 34 is disposed between the pole 33, the rotating cam 31, and the guide 25c.

  On the side opposite to the surface on which the external teeth 57 of the pole 33 are formed, a recess 33c extending in a direction intersecting the radial direction of the relative rotation and a hook portion 33a are formed. On the side opposite to the surface on which the external teeth 58 of the pole 32 are formed, a concave portion 32c extending in a direction intersecting with the radial direction of relative rotation and a hook portion 32a are formed.

  On the other hand, three hook portions 31 b that can enter the concave portion 33 c of the pole 33 and the concave portion 32 c of the pole 32 are formed on the peripheral portion of the rotating cam 31.

  On the surface of the pole 33 opposite to the surface on which the external teeth 57 are formed, a lock surface 33b on which the cam 34 can abut is formed. The lock surface 33b intersects the radial direction of the relative rotation, and when pressed by the cam 34, the force pressing the pole 33 against the guide 25c and the direction in which the outer teeth 57 mesh with the inner teeth 23 (radial direction of the relative rotation). It is set to a surface where a force for moving the pole 33 is generated. On the surface of the pole 32 opposite to the surface on which the external teeth 58 are formed, a lock surface 32b is formed on which the hook portion 31b of the rotating cam 31 can abut.

  Further, a rotating cam abutting portion 33d on which a cam abutting portion 31c formed on a portion other than the hook portion 31b of the rotating cam 31 can abut on the hook portion 33a of the pole 33 and the hook portion 32a of the pole 32. A cam contact portion 32d is formed.

  When the rotating cam 31 rotates in one direction (counterclockwise in FIG. 4), the hook portion 31b of the rotating cam 31 presses the cam 34, and the cam 34 presses the guide 25c and the lock surface 33b of the pole 33. Then, the pole 33 is moved in a direction away from the axis of relative rotation, and the outer teeth 57 of the pole 33 become a locked position where the teeth engage with the inner teeth 23 of the ratchet 21. Further, the hook portion 31b of the rotating cam 31 presses the lock surface 32b of the pole 32, moves the pole 32 in a direction away from the axis of relative rotation, and the external teeth 58 of the pole 32 mesh with the internal teeth 23 of the ratchet 21. Lock position.

  At this time, a gap is generated between the cam contact portion 31 c of the rotating cam 31 and the rotating cam contact portion 33 d of the pole 33.

  In this embodiment, three arcuate large guides 71 along the circumferential direction formed on the inner cylindrical surface on the bottom 21a side from the inner teeth 23 of the ratchet 21 and the bottom 21a of the ratchet 21 of the pole 33 are opposed to each other. An unlocking holding mechanism is provided which includes a protrusion 73 formed by half punching on the surface and a protrusion 74 formed by half punching on the surface facing the bottom 21a of the ratchet 21 of the pole 32. .

  In the present embodiment, the annular step portion 22 is formed on the bottom portion 21 a of the ratchet 21 along the inner cylinder surface, and the large guide 71 is formed continuously with the annular step portion 22.

  Then, as shown in FIG. 7, when the protrusion 73 of the pole 33 and the protrusion 74 of the pole 32 abut on the standing wall surface 71 a of the arcuate large guide 71, the pole 33 and the pole 32 are connected to the external teeth 57, The outer teeth 58 and the inner teeth 23 of the ratchet 21 are held at the unlocked position where the meshing is released.

Furthermore, a small guide 72 is formed in the annular step portion 22 between the large guides 71 of the ratchet 21 by forming a recess 22a on the inner tooth 23 side. As shown in FIG. 8, a surface facing the bottom portion 21 a of the ratchet 21 of the pole 33 and the pole 32 rides on a surface 72 a parallel to the bottom portion 21 a of the ratchet 21 of the small guide 72. The height of the small guide 72 (the height from the bottom 21a of the ratchet 21 to the surface 72a of the small guide 72 (indicated by H in FIG. 8)) is the tip side slope 23c and the root side slope 23d of the internal teeth 23. 8 is set higher than the height (indicated by h in FIG. 8) of the ratchet 21. Therefore, when the pole 33 and the pole 32 ride on the surface 72a of the small guide 72, the external teeth 57, The external teeth 58 of the pole 32 do not mesh with the tooth tip side inclined surface 23c and the tooth bottom side inclined surface 23d of the inner tooth 23, and there is no incomplete meshing of the teeth. The noncircular through hole 31a of the rotating cam 31 has a cross-sectional shape. An operation member 77 that is non-circular (oval) and rotates integrally with the rotary cam 31 is fitted in. The operation member 77 has a cylindrical shape with both end surfaces open, and the outer peripheral surface includes an outer periphery. A half of the operation member 77 is disposed in the entire circumferential direction of the surface. A flange portion 75 is formed which protrudes in the direction and abuts against the bottom portion 21a of the ratchet 21 and prohibits the operation member 77 from being tilted in any direction with respect to the bottom portion 21a of the ratchet 21. The flange portion of the present embodiment. 75 is composed of one continuous collar formed over the entire circumferential direction of the outer peripheral surface of the operation member 77.

  Further, the operation member 77 is set to a height that is exposed to the outside from the hole 25b through which the base plate 25 passes.

  On the externally exposed surface of the base plate 25, two spring locking projections 25f and 25g are formed on the center side of the base plate 25 from the mounting projection 25e (see FIG. 5).

  A spiral spring 79 obtained by processing a long spring plate into a spiral shape is disposed on the externally exposed surface of the base plate 25 where the mounting protrusions 25d and 25e are formed. The inner end 79a of the spiral spring 79 is wound and locked around the operation member 77, and the outer end is used for locking one of the two spring locking protrusions 25f and 25g of the base plate 25. It is locked to the protrusion 25f. The poles 33 and 32 are urged in the lock position direction via the rotating cam 31 by the urging force of the spiral spring 79.

  In the reclining device of this embodiment, as shown in FIGS. 3 and 6, a shaft 91 driven by an operation handle or the like is attached to the operation member 77. The cross-sectional shape of the shaft 91 is a non-circular shape that can be fitted into the hole of the operation member 77, and is set to rotate integrally with the operation member 77 by fitting.

  Further, a spring cover 101 that covers the spiral spring 79 is provided on the externally exposed surface of the base plate 25.

  Here, the operation of the reclining device of the present embodiment will be described.

  As shown in FIG. 4, when no operating force is applied to the rotating cam 31, the rotating cam 31 rotates in one direction (counterclockwise in the figure) by the urging force of the spiral spring 79, and the rotating cam 31. The hook portion 31 b presses the lock surface 32 b of the pole 32. Further, the hook portion 31 b of the rotating cam 31 presses the lock surface 33 b of the pole 33 via the cam 34. When the lock surface 32b of the pole 32 and the lock surface 33b of the pole 33 are pushed, the force that moves the pole 32 and the pole 33 in the direction in which the outer teeth 58 and the outer teeth 57 mesh with the inner teeth 23 (the radial direction of relative rotation). Occurs, and the outer teeth 58 and the outer teeth 57 of the pole 32 and the pole 33 are in a locked position where they are engaged with the inner teeth 23 of the ratchet 21. Therefore, relative rotation between the ratchet 21 and the base plate 25 is prohibited, and the seat back is in a state (locked state) where the seat back cannot rotate with respect to the seat cushion.

  When the shaft 91 is rotated against the urging force of the spiral spring 79 and the pawl 33 is in the locked position, the rotating cam 31 (the operating member 77) rotates in the other direction (clockwise in the figure). The hook portion 31b of 31 enters the concave portion 32c of the pole 32 and the concave portion 33c of the pole 33, and engages with the hook 32a and the hook portion 33a of the pole 32 and the pole 33 (the center of rotation of the relative rotation of the concave portion 32c and the concave portion 33c). The pole 32 and the pole 33 are pulled up in a direction approaching the axis of relative rotation, and the pole 32 and the pole 33 are engaged with the external teeth 58 and 57 and the internal teeth 23 of the ratchet 21. The unlocked position (full open state) is released. Accordingly, the ratchet 21 and the base plate 25 can be relatively rotated, and the seat back can be rotated with respect to the seat cushion.

  After obtaining the desired rotation angle of the seat back with respect to the seat cushion, when the operating force to the shaft 91 is released, the rotating cam 31 rotates counterclockwise by the urging force of the spiral spring 79.

  When the rotating cam 31 rotates counterclockwise, first, the cam contact portion 31c of the rotating cam 31 contacts the pole 32, the rotating cam contact portion 32d of the pole 33, and the rotating cam contact portion 33d. Push 33 in the locking direction.

  Further, when the rotating cam 31 rotates, the cam contact portion 31c of the rotating cam 31 contacts the pole 32, the rotating cam contact portion 32d of the pole 33, and the rotating cam contact portion 33d to lock the pole 32 and the pole 33. Push in the direction. Further, the hook portion 31 b of the rotating cam 31 starts to press against the cam 34, and the cam 34 starts to move in the direction of the lock surface 33 b of the pole 33. Further, the hook portion 31 b of the rotating cam 31 starts to move toward the lock surface 32 of the pole 32.

  Further, when the rotary cam 31 rotates, the cam contact portion 31c of the rotary cam 31 begins to move away from the pole 32, the rotary cam contact portion 32d of the pole 33, and the rotary cam contact portion 33d. The hook portion 31b starts to press the lock surface 32b of the pole 32. Further, the locking surface 33b of the pole 33 starts to be pressed through the cam 34. The rotating cam 31 rotates and the pole 32 and the pole 33 are pushed to the locked position shown in FIG. 4, and the external teeth 57 of the pole 33, the external teeth 58 of the pole 32, and the internal teeth 23 of the ratchet 21 mesh with each other without backlash. Return to the locked state.

  When the seat back stands up and can be seated (first-stage locked state) and the forward-turned state, even if the operation force to the operation member 77 is released by the above-described lock release holding mechanism, the lock release position The pole 32 and the pole 33 are held on the seat back, and the seat back can be rotated without operating the operation member 77. That is, between the first-stage locked state and the forward tilted state, the protrusions 74 and 73 of the pole 32 and the pole 33 are located on the large arc-shaped guide 71, and the operation force to the operation member 77 is released. In addition, the pole 32 and the pole 33 are held at the unlocked position, and the ratchet 21 and the base plate 25 can be rotated relative to each other.

  Next, a method for manufacturing the ratchet 21 and a ratchet manufacturing apparatus will be described with reference to FIGS.

  The ratchet 21 is formed by subjecting the workpiece 80 made of a metal plate material to press working or shear punching using a progressive press device. In the progressive press apparatus, the holes 21b, the mounting protrusions 25d, the surface 72a of the small guide 72, and the large guide 71 are first formed in the ratchet 21, and the internal teeth 23 are formed in the steps shown in FIGS. The outer shape of the ratchet 21 is punched.

  As shown in FIG. 9, the workpiece 80 is sandwiched by the upper mold pressure plate 120 and the lower mold pressure plate 110 having through holes with the surface (open surface) side of the ratchet 21 facing upward. The cylindrical upper die inner punch 134 and the lower die inner punch 142 form the mounting protrusion 25d, the surface 72a of the small guide 72, and the large guide 71.

  A cylindrical gear extrusion punch 132 is provided outside the upper die inner punch 134, and a cylindrical gear ejector 140 is provided outside the lower die inner punch 142. The gear extrusion punch 132 and the gear ejector 140 are in a positional relationship sandwiching the front and back of the portion of the ratchet 21 where the small guide 72 (and the large guide 71) is formed. Outer teeth for forming the inner teeth 23 are formed on the outer peripheral portion of the gear extrusion punch 132. A floating main punch 130 is provided outside the gear extrusion punch 132, and a floating die 111 is provided outside the gear ejector 140.

  In the state of FIG. 9, the inner teeth 23 and the cylindrical portion of the ratchet 21 are not formed, the tips of the gear extrusion punch 132, the floating main punch 130, and the upper die pressure plate 120 are substantially flush, and the gear ejector 140, the floating die 111 and the tip of the lower mold pressure plate 110 are substantially flush with each other.

  In the process of FIG. 10 subsequent to FIG. 9, the outer die punching of the ratchet 21 is performed by the relative movement of the floating main punch 130 downward relative to the lower die pressure plate 110 while applying back pressure from the back side of the ratchet 21 by the floating die 111. Is done.

  Subsequently, the process proceeds to the step of FIG. The small guide 72 is sandwiched between the gear extrusion punch 132 and the gear ejector 140, and is sandwiched between the floating main punch 130 and the floating die 111. The molds are moved in the vertical direction so that the cylindrical portion of the ratchet 21 is formed, and the internal teeth 23 are formed by the external teeth formed on the outer peripheral portion of the gear extrusion punch 32 (half punching process).

  Here, the front end portion of the pushing direction of the gear push punch 132 will be described with reference to FIG. A tooth profile 133 that forms the inner teeth 23 is formed on the outer peripheral surface of the gear extrusion punch 132 by half-punching. The tooth profile at the corner of the tip surface in the pushing direction (arrow A direction in the figure) includes a tooth tip forming portion 133a that forms the tooth tip 23a side of the internal tooth 23, and a tooth bottom that forms the tooth bottom 23b side of the internal tooth 23 Both the forming portion 133b and the conical surface of the tooth tip forming portion inclined surface 133c, and the conical surface of the tooth bottom forming portion inclined surface 133d gradually decrease in the diameter of the tooth tip circle and the root circle of the inner tooth 23 as approaching the tip surface. Is formed.

  Then, the inclination angle (α) of the tooth tip forming portion inclined surface 133c and the inclination angle (β) of the tooth bottom forming portion inclined surface 133d were set to be different. In addition, the inclination angle of the tooth tip forming portion slope 133c and the tooth bottom forming portion slope 133d of the gear extrusion punch 132 is the same as that of the tooth tip side slope 23c and the tooth bottom side slope 23d of the ratchet 21 (the conical surface). ) And the central axis of the gear extrusion punch 132.

  And in this embodiment, the inclination-angle ((alpha)) of the tooth-tip formation part inclined surface 133c was 15 degrees-45 degrees, More preferably, it was 30 +/- 5 degrees.

  Further, the gear extrusion punch 132 is set deeper in the pushing direction than the tooth tip forming portion inclined surface 133c, the tooth bottom forming portion inclined surface 133d, the tooth tip forming portion inclined surface 133c, and the tooth bottom forming portion inclined surface 133d. The recessed portion 132a is formed, and the tooth tip forming portion inclined surface 133c, the tooth bottom forming portion inclined surface 133d, and the protruding portion 132b formed between the recessed portion 132a are formed. A concave portion 22a is formed on the annular step portion 22 by the convex portion 132b, and the small guide 72 is completed (formed) by the formation of the concave portion 22a.

  The inventor of the present application conducted the following experiment.

 (1) Clearance between mold (gear pushing punch 132) and mold (floating main 130): negative clearance was 0.2 mm.

In general, it is said that the better the fluidity of the material, the less stress is applied to the mold, resulting in a longer mold life. From this, the damage value = C ₁ (1 formula) derived from the Cockcroft & Latham model, one of the ductile fracture formulas of materials, is used as a characteristic value, and the tip angle θ of the die (punch) and the occurrence of fracture The relationship was analyzed by CAE (computer aided engineering). The result is shown in FIG. In FIG. 13, the vertical axis represents the fracture occurrence rate, and the horizontal axis represents the tip angle of the punch.

  According to this experiment, it was found that the fracture occurrence rate changes two-dimensionally in a convex manner depending on the punch tip angle, and there is a minimum value when θ is between 15 degrees and 45 degrees.

  And it has confirmed that 30 +/- 5 degree was optimal.

  According to the above configuration, the following effects can be obtained.

 (1) Since the tooth tip forming part and the tooth bottom forming part of the punch forming the inner teeth 23 of the ratchet 21 are slopes, the meat easily moves, the amount of sagging is reduced, and there is a problem in the formation of the internal teeth. Does not occur.

 (2) For those who want to make accurately the tooth bottom or tooth tip of the inner tooth 23 of the ratchet 21 by the inclination angle of the inclined surfaces of the tooth tip forming portion 133a and the tooth bottom forming portion 133b of the gear push punch 132 being different. It becomes easy to control the movement of meat.

 (3) The tooth tip forming portion inclined surface 133c of the gear extrusion punch 132 is a conical surface, and the inclination angle (α) between the generatrix of the conical surface and the central axis of the gear extrusion punch 132 is set to 15 to 45 degrees. As a result, the tooth tip slope portion 23c and the bottom slope portion 23d of the inner teeth 23 of the ratchet 21 are less likely to break.

 (4) By setting the inclination angle (α) of the tooth tip forming portion slope 133c of the gear push punch 132 to 30 ± 5 degrees, the tooth tip slope portion 23c of the inner tooth 23 of the ratchet 21 and the tooth bottom slope portion 23d break. Is less likely to occur.

 (5) The ratchet 21 is formed on the distal end surface of the gear pushing punch 132 in the pushing direction by forming a recess 132a deeper than the tooth tip forming portion inclined surface 133c and the tooth bottom forming portion inclined surface 133d in the pushing direction. A small guide 72 is formed. Therefore, the meshing failure of the external teeth 57 of the pole 33, the external teeth 58 of the pole 32, and the internal teeth 23 of the ratchet 21 is eliminated.

21 Ratchet 23 Internal teeth

Claims (7)

In the ratchet manufacturing method for a bottomed cylindrical reclining device in which inner teeth are formed along the circumferential direction on the inner cylindrical surface, and one surface is an open surface,
A tooth profile that forms the inner teeth is formed on the outer peripheral surface by half-punching, and the tooth profile is a tooth tip forming portion that forms the tooth tip side of the inner teeth, and a tooth bottom that forms the tooth bottom side of the inner teeth Formed at the end of the outer peripheral surface in the pushing direction of the tooth profile is formed with an inclined surface in which the diameter of the tooth tip forming portion and the tooth bottom forming portion gradually decreases as approaching the tip surface, A ratchet manufacturing method for a reclining device, wherein the ratchet is manufactured using punches having different inclination angles between the inclined surface of the tooth tip forming portion and the inclined surface of the tooth bottom forming portion. The slope of the tooth tip forming portion of the punch is a conical surface,
The ratchet manufacturing method for a reclining device according to claim 1, wherein an inclination angle between a generatrix of the conical surface and a central axis of the punch is 15 to 45 degrees.   The ratchet manufacturing method for a reclining device according to claim 2, wherein an inclination angle formed between a generatrix of the conical surface of the punch and a central axis of the punch is 30 ± 5 degrees. On the front end surface in the pressing direction of the punch,
The ratchet of the reclining device according to any one of claims 1 to 3, wherein a concave portion set deeper than an inclined surface of the tooth tip forming portion and an inclined surface of the tooth bottom forming portion in the pushing direction is formed. Production method. In the reclining device having a bottomed cylindrical ratchet in which inner teeth are formed along the circumferential direction on the inner cylindrical surface and one surface is an open surface,
Both the tooth tip side of the inner tooth on the bottom side of the ratchet and the tooth bottom side of the inner tooth, the tooth tip circle, the tooth tip side slope, the tooth bottom side, the diameter of the root circle gradually decreases toward the bottom A slope is formed,
The reclining device, wherein the inclination angle of the tooth tip side slope and the tooth bottom side slope is different. A base plate that is laminated on the open surface side of the ratchet, and is provided so as to be relatively rotatable in the circumferential direction with the ratchet;
A pole formed movably on the base plate and formed with external teeth that can mesh with the internal teeth;
Have
At the bottom of the ratchet,
The guide which holds the said pole is formed so that the external teeth of the said pole may not mesh with the tooth tip side slope surface and the tooth bottom side slope of the internal teeth of the ratchet. Reclining device. In the ratchet manufacturing apparatus of the reclining apparatus for manufacturing a bottomed cylindrical ratchet in which inner teeth are formed along the circumferential direction on the inner cylindrical surface and one surface is an open surface,
It has a punch that half-punches the plate material,
The punch has a tooth profile that forms the inner teeth by half-punching on an outer peripheral surface, and the tooth profile forms a tooth tip forming portion that forms a tooth tip side of the inner teeth, and a tooth bottom side of the inner teeth. An inclined surface comprising a bottom forming portion to be formed, and the end portion of the outer peripheral surface in the pushing direction of the tooth profile gradually decreases in diameter as the tip formation portion and the bottom formation portion become closer to the tip surface. The ratchet manufacturing apparatus for a reclining device is characterized in that the inclination angle of the inclined surface of the tooth tip forming portion and the inclined surface of the tooth bottom forming portion is different.