JP5579457B2 - Sheet fixing device - Google Patents

Description

  The present invention relates to a sheet fixing device that suppresses the occurrence of play in a fixed sheet.

  Vehicles include a configuration in which the seat back of a seat composed of a seat cushion and a seat back can be folded forward and folded, a configuration in which the seat cushion can be flipped up, and the like. In these seats, a seat fixing device is provided so that the seat cushion and the seat back can be detachably fixed to the vehicle body.

  As a conventional sheet fixing device, for example, one disclosed in Patent Document 1 is known. As shown in FIG. 1 of Patent Document 1, the seat fixing device engages the base plate 1 having the striker entry groove 23 and the striker 18 entering the striker entry groove 23, and rotates about the latch shaft 37. The latch 31 is rotatable about the plate shaft 47, the locking plate 33 having the engagement hook 45 engaged with the latch engaging portion 51 of the latch 31, and the plate shaft 47 is rotatable. The striker regulation which has the 1st stopper 57 and the 2nd stopper 59 which pinch | interpose the part of the projection part 43 of the upper part of the locking plate 33 from the circumferential direction, contacts the striker 18 which entered the striker entrance groove 23, and regulates the striker 18 Biasing means 39 for rotating the member 35, the latch 31, and the striker regulating member 35 counterclockwise. It is constituted by. In a state where the striker 18 is located at the innermost position of the striker entry groove 23, there is a gap between the latch engagement portion 51 of the latch 31 and the engagement hook 45 of the locking plate 33. The striker restricting member 35 is urged counterclockwise by the urging force and pressed against the striker 18, and the latch 31 rotates counterclockwise to engage the locking plate 33 with the latch engaging portion 51 of the latch 31. Since the mating hook 45 is engaged, in this locked state, the gap is eliminated and sheet rattling is prevented.

  On the other hand, the sheet fixing device described in Patent Document 2 is centered on the first support pin 11 with the case 2 having the guide groove 10 and the striker 7 entering the guide groove 10 engaged with the holding groove 13. A fork 3 that rotates, a lock plate 4 that is provided so as to be rotatable about the second support pin 12 and has a locking surface 17 that locks the locking portion 15 of the fork 3, and the second support pin 12. A control member 5 that is pivotable about the center and restricts the cam surface 20 from engaging with the engaging member 9 of the fork 3 and rotating the fork 3 counterclockwise, and an upper portion of the fork 3 and the lock plate 4. And a spring 8 for urging the control member 5 clockwise with respect to the lock plate 4. By rotating the fork 3, the striker 7 bitten into the holding groove 13 of the fork 3 is pressed to the back of the guide groove 10, and the striker 7 is disposed on the fork 3 and the buffer rubber body 6 provided at the innermost side of the guide groove 10. The striker 7 is supported at two points to prevent the striker 7 from rattling.

Japanese Patent Laid-Open No. 08-260788 JP 2006-15892 A

  However, in the seat fixing device described in Patent Document 1, since the striker restricting member 35 is urged counterclockwise and pressed against the striker 18, the latch 31 together with the striker 18 faces the outlet of the striker entry groove 23. When the weight of the occupant is added to the seat, the base plate 1 is locked. The base plate 1 has a clearance between the innermost inner surface of the striker entry groove 23 and the striker 18. May move relative to the striker 18, and the latch 31 may be rotated clockwise together with the striker 18 against the urging force of the striker restricting member 35.

  On the other hand, since the sheet fixing device described in Patent Document 2 is configured to support the striker 7 at two points of the fork 3 and the shock absorbing rubber body 6, when the shock absorbing rubber body 6 deteriorates and the elastic force decreases, When a heavy load is applied to the seat when the weight of the occupant is applied, the portion of the case 2 swings with respect to the striker 7 with the two points of the fork 3 and the shock absorbing rubber body 6 with which the striker 7 abuts as a fulcrum. The holding power of the striker 7 is reduced.

  SUMMARY An advantage of some aspects of the invention is that it provides a sheet fixing device that solves the above-described problems.

The invention according to claim 1 includes a striker fixed to a vehicle body and catch means provided on a seat for catching the striker, wherein the catch means includes a pair of base plates fixed to the seat, and each of the base plates. A first insertion portion that is formed at an approximately middle position from the outer peripheral portion toward the inside and into which the striker is inserted and removed, and a latch that connects the pair of base plates to one side with respect to the first insertion portion of the pair of base plates A latch which is pivotably provided via a shaft and occupies a lock position and a lock release position and is urged to rotate from the lock position toward the lock release position; and each of the first fittings provided in the latch A second insertion part into which the striker that enters the part enters and leaves, and the first insertion part of the pair of base plates on the other side A lock position is provided via a lock shaft that couples the pair of base plates, and the latch occupies a restraining position for restraining the latch from being pivoted and turning from the lock position to the unlock position, and an allowable position. And a lock plate that is urged to rotate from the allowable position toward the restraint position, and the lock plate is manually unlocked against the rotation urge to rotate from the restraint position to the allowable position. An operation portion formed on the lock plate; and a cam that is rotatably provided on the lock shaft and is urged to rotate in a direction of pressing the latch toward the lock position when the latch occupies the lock position. , The outermost width dimension of each of the first insertion portions is set to be smaller than the outer diameter dimension of the striker, and the outer peripheral surface of the striker is the respective With contact with an inner surface and two contact points of the first fitting portion, characterized in that it abuts the inner surface and a single contact point of the second fitting portion.

  According to the present invention, when the striker is locked, the rotationally biased cam pressurizes the latch toward the lock position, and the outer peripheral surface of the striker has two inner surfaces of the first insertion portion of the pair of base plates. The striker abuts at a total of five points because it abuts at this contact point and abuts against the inner surface of the second fitting portion of the latch at a single abutment point. Since the striker is in contact with the circumferential direction at three contact points, the striker does not move relative to the catch means in any direction on the outer periphery of the striker, and the striker is paired in the axial direction of the striker. Since the back side of the first insertion portion of the base plate abuts at two abutment points and the entrance side abuts at a single abutment point by the latch, the catch means does not fall relative to the striker. .

  The invention according to claim 2 is the seat fixing device according to claim 1, wherein two contact points at which an outer peripheral surface of the striker contacts an inner surface of the first insertion portion of the base plate, and the first of the latches. A single contact point that contacts the inner surface of the two insertion portions is disposed at substantially equal intervals along the outer periphery of the striker.

  According to this invention, the three points of the two contact points on the inner surface of the first insertion portion of the base plate that contacts the striker and the single contact point that contacts the inner surface of the second insertion portion of the latch are the outer periphery of the striker. , The striker is reliably prevented from moving relative to the catch means in any direction of the outer periphery of the striker at 360 degrees.

  According to the seat fixing device of the first aspect, the striker does not move relative to the catch means in any direction on the outer periphery of the striker, and the striker falls over the catch means. Therefore, the holding of the striker by the catching means is stable, and even if a large load is applied to the seat, the catching means will not cause relative backlash or collapse with respect to the striker, and the support rigidity of the seat can be improved. I can plan. In addition, since the striker makes contact at three locations on the outer periphery, the gripping force is 1.5 times that of the conventional contact at two locations, and the striker rotates or slides in the axial direction relative to the catch means. Since this is suppressed, there is an effect equivalent to increasing the urging force of the cam that pressurizes the latch.

  According to the seat fixing device of the second aspect, since the striker is supported by the catch means at an equal interval of 360 degrees on the outer periphery of the striker, the holding of the striker by the catch means is further stabilized.

The disassembled perspective view of the catch means in the sheet fixing device (embodiment). The block diagram of the locked state of the fixing device of a sheet | seat (embodiment). The block diagram of the state which the cam of the fixing device of a sheet occupies the lock starting point position (embodiment). The block diagram of the state which the cam of the fixing device of a sheet | seat occupies a lock release transfer position (embodiment). The block diagram of the unlocking state of the sheet fixing device (embodiment). FIG. 5A is a configuration diagram of a seat using a seat fixing device for a seat back, and FIG. 5B is a configuration diagram of a seat using a seat fixing device for a seat cushion (embodiment). (A) is a principal part enlarged view which shows the shape of a 1st insertion part, (b) is a perspective view (embodiment) which shows the position of a contact point. Action | operation explanatory drawing which shows the direction of the force which acts on a cam from a projection part in a locked state (embodiment). Action | operation explanatory drawing (embodiment) which shows the direction of the force which acts on a cam when a lock release operation is performed and a cam occupies a lock release transition position. Action | operation explanatory drawing which shows the direction of the force which acts on a cam from a projection part by comparing with a locked state and the state which a cam occupies a lock release transition position (embodiment). Explanatory drawing which shows the relationship between a latch and a lock plate when a cam occupies a lock starting point position (embodiment).

Hereinafter, embodiments of a sheet fixing device according to the present invention will be described.
(Constitution)
As shown in FIG. 6 (a), a seat back 1 b is rotatably provided with respect to the seat cushion 1 a to constitute a rear seat 1. The seat cushion 1a is coupled to a vehicle body 2a which is a floor surface via a bolt (not shown), and the seat back 1b is detachably attached to the vehicle body 2b which is a standing surface. On the other hand, FIG. 6B shows a structure in which the front portion of the seat cushion 1a is configured to be rotatable via a hinge, and the rear portion of the seat cushion 1a is detachably attached to the vehicle body 2a.

  A seat fixing device 3 is provided for detachably attaching the seat cushion 1a to the vehicle body 2a and detachably attaching the seat back 1b to the vehicle body 2b. The sheet fixing device 3 includes a striker 4 and catch means 5. The striker 4 is formed by bending a rod-like member into a U shape and fixing both ends thereof to the vehicle bodies 2a and 2b. On the other hand, the catch means 5 is embedded in the lower surface of the seat cushion 1a and the rear surface of the seat back 1b, and can catch or release the striker 4.

  The structure of the catch means 5 is demonstrated based on FIG. 1, FIG. A pair of base plates 7 and 8 constituting the catch means 5 are fixed to a frame (not shown) of the seat cushion 1a and the seat back 1b. One base plate 7 has a substantially planar configuration as shown in FIG. 1, and the other base plate 8 has a configuration having an accommodation space. In the base plates 7 and 8, first insertion portions 7a and 8a, which are cutout portions for allowing the striker 4 to relatively enter and leave, are formed at substantially intermediate positions in the length direction from the outer peripheral portion toward the inside. Has been.

  As shown in FIG. 2, a latch 10 is rotatably provided on the left side of the first insertion portions 7a and 8a of the base plates 7 and 8 via a latch shaft 9 connecting the base plates 7 and 8. . The latch 10 is formed with a second insertion portion 10a for the striker 4 entering the first insertion portions 7a and 8a to enter and exit. The latch 10 occupies a locked position and an unlocked position. The lock position refers to the rotational position of the latch 10 when the striker 4 enters the first insertion portions 7 a and 8 a and the striker 4 enters the second insertion portion 10 a of the latch 10 as shown in FIG. 2. On the other hand, the unlocking position refers to a rotational position of the latch 10 when the striker 4 can be discharged from both insertion portions as shown in FIG.

  A lock plate 12 is rotatably provided via a lock shaft 11 connecting the base plates 7 and 8 on the right side with respect to the first fitting portions 7a and 8a of the base plates 7 and 8. In order to restrain the latch 10 in the locked position, the latch 10 is formed with an engaging portion 10b protruding rightward in FIG. 2, while a lock-shaped lock portion 12a is formed below the lock plate 12. Is formed. The lock plate 12 occupies a restraining position (FIG. 2) that restrains the latch 10 from rotating from the locked position to the unlocked position and an allowable position (FIG. 5) that allows the latch 10 to rotate. In order to urge the lock plate 12 to rotate from the allowable position to the restraining position, a spring 13 is provided as an urging means. The spring 13 is provided in a state of being wound around the lock shaft 11, one end of which is hooked on the side wall 8 b of the base plate 8, and the other end is inserted through a spring hooking hole 12 b formed in the lock plate 12.

  A protrusion 10c is provided in a state protruding from the latch 10 in the axial direction at a position opposite to the first insertion portion 7a, 8a with respect to a line segment connecting the latch shaft 9 and the lock shaft 11. It has been. On the other hand, a cam 14 that pressurizes the protrusion 10c is rotatably provided on the lock shaft 11. When the latch 10 occupies the lock position of FIG. 2, the cam 14 is urged to rotate in the pressurizing direction from the vicinity of the first insertion portions 7a and 8a toward the projection portion 10c. It has a cam surface 14c that pressurizes the latch 10 toward the lock position.

  In order to urge the cam 14 to rotate in the pressurizing direction and urge the latch 10 to rotate from the locked position toward the unlocked position, a spring 15 is provided as an urging means surrounding the latch shaft 9. It has been. One end of the spring 15 is hooked on the spring hooking portion 10 d of the latch 10, and the other end is inserted through the long hole 14 a of the cam 14.

  In order to rotate the lock plate 12 from the restraining position to the permissible position by manually releasing the lock against the urging force of the spring 13, an operation portion 12c is integrally formed on the upper portion of the lock plate 12. A through hole 12f for connecting the lower end of the release rod 17 in FIG. 6A and the end of the wire 17b in FIG. 6B is formed in the upper end portion of 12c. Further, the cam 14 is pressed against the urging force of the spring 15 in the direction opposite to the pressurizing direction by the unlocking operation of the operation portion 12c and rotated to the unlocking transition position B shown in FIG. A pressing portion 12d is formed in the lock plate 12 in the vicinity of the lock shaft 11. On the other hand, a pressed portion 14b for pressing by the pressing portion 12d is formed on the cam 14 so as to protrude in the axial direction.

  In FIG. 1, the base plates 7 and 8 are formed symmetrically with respect to the first insertion portions 7a and 8a as a reference, and are inserted into the right side of the two left and right coupling holes 7c and the coupling holes 8c. 16, the latch shaft 9, and the lock shaft 11, and two catching bolts (not shown) are inserted into the mounting holes 7 d and 8 d arranged at the left and right ends, and the catch means 5 is shown in FIG. As shown in (a) and (b), the seat back 1b and the seat cushion 1a are coupled to a frame (not shown). In order to support both ends of the latch shaft 9 and the lock shaft 11, four shaft holes 7e and 8e are formed in the base plates 7 and 8, respectively. In this embodiment, four shaft holes 7e and 4e are formed. Of the two shaft holes 8e, the upper right one and the lower left one are used. In this embodiment, the operation direction of the operation portion 12c is the left direction in FIG. 2, but when the operation direction is to be the right direction, the upper left and lower right ones of the shaft holes 7e and 8e are used, and The lower left coupling holes 7c and 8c are used.

  In this invention, when the operation portion 12c is moved to the left in FIG. 2 to perform the unlocking operation, the lock plate 12 is rotated from the restraining position to the allowable position, and the pressing portion 12d provided on the lock plate 12 is moved. When the pressed portion 14b of the cam 14 is pressed in the anti-pressurizing direction and the cam 14 is rotated to the unlocking transition position B in FIG. The latch 10 is urged by the spring 15 to be rotated in the opposite direction, that is, in the opposite direction, whereby the latch 10 pushes the cam 14 and rotates from the locked position to the unlocked position. Has been. That is, when the cam 14 rotates to the unlocking transition position B, the pressing direction in which the protrusion 10c presses the cam 14 by the bias of the spring 15 is determined from the contact point between the cam 14 and the protrusion 10c. The direction toward the vicinity of the lock shaft 11 between the shaft 9 and the direction toward the vicinity of the intermediate portion between the lock shaft 11 and the latch shaft 9 is switched, whereby the spring 15 is biased in the pressurizing direction. The cam 14 that has been set is urged in the anti-pressurizing direction by the urging force of the protrusion 10c with a force larger than the urging force, and the cam 14 is set to rotate in the anti-pressurizing direction. Specifically, it is configured as follows.

  The protrusion 10c of the latch 10 is formed with a flat surface portion 10h by cutting out a part of the outer peripheral surface of the cylinder, and as shown in an enlarged view in FIG. The large arc portion 10d having a large diameter is in contact with the end portion 14d of the cam surface 14c and is formed at a corner between the large arc portion 10d and the flat surface portion 10h. The radius dimension is sufficiently larger than the large arc portion 10d. And a small small circular arc portion 10e.

In the locked state, as shown in FIG. 8, the cam surface 14c of the cam 14 abuts against the large circular arc portion 10d of the protrusion 10c, and the cam 14 pressurizes the protrusion 10c, so that the lock plate 12 is rotated from the restraint position to the allowable position. When moved, the pressing portion 12d of the lock plate 12 presses the pressed portion 14b of the cam 14, so that the cam 14 rotates to the unlocking transition position B in the non-pressurizing direction shown in FIG. The end portion 14d of 14c contacts the small arc portion 10e. That is, the contact point of the cam 14 with respect to the protrusion 10c is configured to move from the large arc portion 10d to the small arc portion 10e. The direction of the force F ₁ acting on the cam 14 from the large arc portion 10d and the small arc portion 10e when the cam 14 contacts the large arc portion 10d and the small arc portion 10e is the center of the large arc portion 10d and the small arc portion 10e. And the contact point. For this reason, as shown in FIG. 10, since the direction of F ₁ when the cam 14 abuts on the large circular arc portion 10d is always perpendicular to the tangent, the rotational moment that rotates the cam 14 in the anti-pressurizing direction is generated. On the other hand, the direction of F ₁ when the cam 14 comes into contact with the small circular arc portion 10e generates a rotational moment that rotates the cam 14 in the anti-pressurizing direction. Thus, it is set so as to go in the circumferential direction of a circle centering on the lock shaft 11. That is, in order to significantly change the direction of F ₁ with a small movement of the contact point, is provided with a large difference in the radial dimension of the large arc portion 10d and a small circular arc portion 10e. The contact point is moved in this way because the direction of the force applied from the protrusion 10c to the cam 14 changes, which is opposite to the force in the pressurizing direction in which the cam 14 is urged by the spring 15. In this direction, the projection 10c is set so that the force for rotating the cam 14 becomes larger, and as a result, the cam 14 is pushed by the latch 10 and rotated in the anti-pressurizing direction.

  The unlocking transition position B of the cam 14 is set as follows.

As shown in FIG. 10, the boundary between the large arc portion 10d and the small circular arc portion 10e of the protrusions 10c and the border position A _2. The position of the cam 14 and the lock plate 12 when the cam 14 to the border position A ₂ abuts shown in FIG. This position becomes a lock starting point position A ₁ where the cam 14, the lock plate 12 and the latch 10 can naturally return to the lock position when the operation of the lock lever 12 is stopped.

Next, when the latch 10 is released from the lock plate 12, the contact point of the cam 14 is switched from the large arc portion 10d to the small arc portion 10e, and the latch 10 can be rotated to the unlock position by the biasing force of the spring 15. Is set to The positional relationship between the lock plate 12 and the latch 10 unlocked by the lock plate 12 when the lock plate 12 presses the cam 14 and reaches the lock starting point position A ₁ shown in FIG. Is shown in FIG. While arc portion 10f is formed in the engagement portion 10b of the latch 10, the circular arc portion 12e is formed in the lock portion 12a of the lock plate 12, the locking portion 12a is engaged portion at the position of A ₃ in the arc portion 10f 10b. Be stopped operation of the lock plate 12 in this position, the latch 10 moves from the position of A ₃ in the Y direction is locked by the urging force of the lock portion 12a spring 13, the lock portion 12a by operating the lock plate 12 Further movement in the X direction unlocks the latch 10. Therefore, the switched position the position of A _3.

The lock portion 12a between the slight rotation of the lock plate 12 to become disengaged from the engaging portion 10b of the latch 10 as shown in FIG. 4 from the switched position A ₃ in FIG. 11, the cam 14 projecting The direction perpendicular to the tangent of the protrusion 10c at the contact point of the portion 10c is switched from the large arc portion 10d to the small arc portion 10e having a sufficiently small radius, so that the lock shaft 11 is shifted from the central direction of the lock shaft 11 to the lock shaft 11. It is set so as to change greatly in the circumferential direction of a circle centered on.

Therefore, in the present invention, when the cam 14 is located at the lock start position A ₁ in FIG. 3, the lock portion 12a of the lock plate 12 is at the switching position A ₃ of the engagement portion 10b of the latch 10 as shown in FIG. abut, and the cam 14 is set so as to contact the border position a ₂ of the protrusion 10c shown in FIG. 10.

When the cam 14 abuts against the large circular arc portion 10d of the projection 10c, the cam 14 receives a force F _{1 in} a direction perpendicular to the tangent from the projection 10c, so that the direction of the force is cam as shown by F ₁ in FIG. 14, the rotation moment that rotates the cam 14 in the anti-pressurizing direction through the vicinity of the rotation center O ₂ of the cam 14 hardly acts, and the cam 14 receives only the urging force of the spring 15 and rotates in the pressurizing direction. The latch 10 in the locked position is pressurized toward the locked position. On the other hand, when the cam 14 as shown in FIG. 9 abuts on the small arcuate portion 10e of the protrusion 10c, the cam 14 is for receiving a force F ₁ perpendicular to the tangent line from the protruding portion 10c, in F ₁ in FIG. 9 As shown, the direction of the force is greatly inclined in the circumferential direction of the circle centered on the rotation center O ₂ of the cam 14, and the cam 14 receives a large rotational moment from the projection 10c in the anti-pressurizing direction. Then, the cam 14 rotates in the anti-pressurizing direction, and the latch 10 rotates toward the unlocking position following the rotation of the cam 14. Then, as shown in FIG. 4, when the lock portion 12a of the lock plate 12 is rotated to the allowable position where it is disengaged from the engaging portion 10b of the latch 10, there is no restriction on the rotation of the latch 10, so that the spring 15 is attached. Due to the force, the latch 10 pivots from the lock position to the unlock position in FIG. For this reason, the position B in FIG. 4 where the cam 14 is slightly rotated in the counter-pressurizing direction from the lock starting point position A ₁ shown in FIG.

In the present invention, the following configuration is employed in order to reliably hold the striker 4. The principal part of FIG. 2 is shown in FIG. The innermost width dimension of the first insertion portions 7 a and 8 a is set smaller than the outer diameter dimension of the striker 4. That is, the tapered surfaces 7f and 8f are formed on both innermost sides of the first insertion portions 7a and 8a so that the width dimension becomes smaller toward the innermost portion. For this reason, at the time of locking, the outer peripheral surface of the striker 4 comes into contact with the inner surface of each of the first insertion portions 7a and 8a at two contact points 7g and 8g, respectively, and the outer peripheral surface of the striker 4 is the second insertion portion of the latch 10 It contacts the inner surface of 10a at one point of the contact point 10g. FIG. 7B shows the relationship between the contact points 7g and 8g and the contact point 10g. When the center of the striker 4 and O _5, as shown in FIG. _{7 (a), (O 5} 7g) (O 5 7g) (O 5 10g) The angle between is set to 2 [Theta] = 120 degrees, the striker The contact points 7 g, 7 g, 10 g along the outer periphery of 4 and the contact points 8 g, 8 g, 10 g are arranged at equal intervals along the outer periphery of the striker 4.
(Function)
Next, the operation of the sheet fixing device will be described.

According to the present invention, as shown in FIG. 2, when the latch 10 occupies the locked position and the lock portion 12 a of the lock plate 12 is engaged with the engagement portion 10 b of the latch 10, the cam 14 is biased by the spring 15. Since the protrusion 10c is urged by rotation to pressurize the latch 10 toward the lock position, the inner surface of the second insertion portion 10a of the latch 10 to be pressed and the inner surface of the back of the first insertion portions 7a and 8a The striker 4 is sandwiched between them, and the striker 4 is restrained inside the first insertion portions 7a and 8a so that there is no backlash. Next, for example, by pulling up the release rod 17 in FIG. 6A, the operation portion 12 c shown in FIG. 3 is pulled leftward to perform the unlocking operation, and the lock plate 12 resists the biasing force of the spring 13. Then, when the lock position 12 is rotated counterclockwise from the restraint position, the pressing portion 12d provided on the lock plate 12 presses the pressed portion 14b of the cam 14 against the urging force of the spring 15, and the cam 14 is pressed. In the process in which the cam 14 is rotated slightly beyond the lock starting point position A ₁ shown in FIG. 3 to the unlocking transition position B shown in FIG. 4, the contact portion between the cam 14 and the protrusion 10c changes. As a result of the urging of the spring 15, the rotation moment at which the protrusion 10 c tries to rotate the cam 14 in the anti-pressurizing direction increases. The force by which the protrusion 10c urges the cam 14 to rotate is greater than the force by which the spring 15 urges the cam 14, and the lock plate 12 rotates to the allowable position and the latch 10 is released. Therefore, as shown in FIG. 4, the latch 10 pushes the cam 14 at the unlocking transition position B in the anti-pressurizing direction, and then the latch 10 rotates to the unlocking position as shown in FIG. 4 is discharged from the first insertion portions 7a and 8a and the second insertion portion 10a. That is, the striker 4 is unlocked.

  As described above, when the cam 14 is rotated to the unlocking transition position B by the pressing portion 12d of the lock plate 12, the contact portion between the rotated cam 14 and the protruding portion 10c changes, and the spring 15 is rotated. A detailed description will be given of the fact that the rotational moment at which the protrusion 10c causes the cam 14 to rotate in the counter-pressurizing direction due to the force increases.

The latch 15 is urged to rotate toward the unlocking position by the spring 15, while the cam 14 is urged to rotate in the pressurizing direction that pressurizes the protrusion 10 c. As shown in FIG. 2, in the state where the latch 10 occupies the lock position, the cam surface 14c of the cam 14 is in contact with the large arc portion 10d of the projection 10c, and at this time, the large arc portion 10d of the projection 10c pressing direction for pressing the surface 14c is tangential and perpendicular direction of the large arc portion 10d of the contact point Q as shown as F ₁ in FIG. 8, direction from the center O ₃ of the large arc portion 10d to the contact point Q Therefore, the pressing direction of the force F _{1 at} which the large circular arc portion 10d presses the cam surface 14c is a direction from the contact point Q to a point T in the vicinity of the lock shaft 11 between the lock shaft 11 and the latch shaft 9. Become.

The value of the force F ₃ for rotating the cam 14 in the anti-pressurizing direction by this F ₁ is obtained as follows. When the spring 15 urges the latch 10 to rotate, the force at which the contact point Q of the protrusion 10c of the latch 10 tries to rotate in the circumferential direction about the rotation center O ₁ of the latch 10 is O in the radial direction. ₁ A direction perpendicular to Q, expressed as force F. When this F is decomposed into a component in a direction perpendicular to the tangent to the large circular arc portion 10d and a component in the direction toward the rotation center O ₁ of the latch 10, F ₁ and F ₂ are obtained. When F ₁ is further decomposed into a component in a direction perpendicular to O ₂ Q connecting the rotation center O ₂ of the cam 14 and the contact point Q and a component in a direction toward the rotation center O ₂ of the cam 14, F ₃ and F ₄ It becomes. The force for rotating the cam 14 in the anti-pressurizing direction around the rotation center O ₂ is a component in a direction perpendicular to O ₂ Q and becomes F ₃ .

On the other hand, the force of the spring 15 that urges the cam 14 to rotate in the pressurizing direction is in a direction perpendicular to the inner surface of the long hole 14a from the contact point S where the spring 15 contacts the cam 14 inside the long hole 14a. Expressed as force P. When this P is decomposed into a component in a direction perpendicular to O ₂ S and a component in a direction parallel to O ₂ S, P ₁ and P ₂ are obtained. When this P ₁ is replaced with a force acting on the contact point Q away from the rotation center O ₂ of the cam 14, (P ₁ ) (O ₂ S) = (P ₃ ) (O ₂ Q) is obtained, and (P ₃ ) = (P ₁ ) (O ₂ S) / (O ₂ Q).

As described above, the force for rotating the Q point of the cam 14 in the counter-pressing direction around the rotation center O ₂ is F ₃ , and the force for rotating in the pressing direction is P _3. The force to be moved is (P ₃ -F ₃ ). Here, since the value of F ₃ is small, the rotational moment acting in the anti-pressurizing direction acting on the cam 14 due to F ₃ is small, and the cam 14 is hardly affected by the projection 10c, so the cam 14 is pressurized. Rotate in the direction.

From the locked state of FIG. 2, when the lock 12 is turned from the restraint position to the allowable position by manually pulling the operation portion 12c to the left as shown in FIG. Presses the pressed portion 14b of the cam 14, and the cam 14 is rotated in the anti-pressurizing direction beyond the lock starting point position A1 in FIG. 3 to the lock release transition position B in FIGS. The end portion 14d of the cam surface 14c contacts the small arc portion 10e (see FIG. 10) of the projection portion 10c, and the pressing direction in which the small arc portion 10e of the projection portion 10c presses the cam 14 at this time is the contact point Q. Since the direction is perpendicular to the tangent line of the small arc portion 10e and is directed from the center O ₄ of the small arc portion 10e toward the contact point Q as shown in FIG. 10, the pressing direction in which the small arc portion 10e presses the cam 14 From the contact point Q in FIG. Click shaft 11 and the intermediate portion direction of the force F ₁ becomes toward the point T in the vicinity of the latch shaft 9, the direction of F ₁ changes to a lower portion of the direction of the arrow in FIG. 10 from the upper direction of the arrow in FIG. 10 .

The value of the force F ₃ for rotating the cam 14 in the anti-pressurizing direction by this F ₁ is obtained as follows. In FIG. 9, the force that is urged by the spring 15 to rotate the contact point Q of the protrusion 10 c of the latch 10 in the circumferential direction around the rotation center O ₁ of the latch 10 is the radial O _1. It can be expressed as a force F in a direction perpendicular to Q. When this F is decomposed into a component in a direction perpendicular to the tangent to the small arc portion 10e and a component in the direction toward the rotation center O ₁ of the latch 10, F ₁ and F ₂ are obtained. Further, when F ₁ is decomposed into a component perpendicular to the line segment O ₂ Q connecting the rotation center O ₂ of the cam 14 and the contact point Q and a component toward the rotation center O ₂ of the cam 14, F ₃ become and F _4. Of these, the force to rotate the cam 14 in the anti-pressurizing direction around O ₂ is the component F ₃ in the direction perpendicular to the line segment O ₂ Q. The force F _{3 in} FIG. 9 is sufficiently larger than the force F _{3 in} FIG.

On the other hand, the force by which the spring 15 urges the cam 14 to rotate in the pressurizing direction is in a direction perpendicular to the inner surface of the long hole 14a from the contact point S where the spring 15 contacts the cam 14 inside the long hole 14a. force is P, becomes the P ₁ and P ₂ is decomposed in a direction perpendicular component P to the line segment O ₂ S and a line segment O ₂ S parallel direction component to. If P ₁ is replaced with a force acting on the contact point Q away from the rotation center O ₂ of the cam 14, (P ₁ ) (O ₂ S) = (P ₃ ) (O ₂ Q) and (P ₃ ) = (P ₁ ) (O ₂ S) / (O ₂ Q)

Accordingly, the force for rotating the cam 14 in the counter-pressurizing direction around the rotation center O ₂ is (F ₃ -P ₃ ), and F ₃ > P _3, so the cam 14 rotates in the counter-pressurizing direction. To do. That is, the force by which the spring 15 urges the protrusion 10c to rotate is greater than the force by which the spring 15 urges the cam 14 to rotate, and the cam 14 rotates in the anti-pressurizing direction.

Here, the long hole 14 a of the cam 14 to which the spring 15 is locked is formed as a long hole inclined with respect to the radial direction passing through the center O _{2 of the} cam 14, thereby moving the latch 10 in the unlocking direction. The urging of the cam 14 and the urging of the cam 14 in the pressurizing direction can be performed by a single spring 15. That is, by inclining the long hole 14a with respect to the radial direction of the center O ₂ , the force P ₁ in the pressing direction of the cam 14 is reduced, and even if a single spring 15 is used, the above F ₃ > The relationship P ₃ can be established. When the biasing of the latch 10 and the biasing of the cam 14 are performed by separate springs, it is not necessary to incline the long hole 14a because the spring force can be set separately.

  According to the present invention, when the striker 4 is locked, the cam 14 that is urged to rotate by the spring 15 pressurizes the latch 10 toward the lock position, and the outer peripheral surface of the striker 4 is formed by the pair of base plates 7 and 8. Since the inner surfaces of the first insertion portions 7a and 8a are in contact with the four contact points 7g, 7g, 8g and 8g, and the inner surface of the second insertion portion 10a of the latch 10 is in contact with the single contact point 10g, FIG. As shown in (b), the striker 4 abuts at a total of five points. As shown in FIG. 7A, the striker 4 is in contact with the circumferential direction at three contact points, so that the striker 4 is relative to the catch means 5 in any direction on the outer periphery of the striker 4. In the axial direction of the striker 4, the back side of the first insertion portions 7 a, 8 a of the pair of base plates 7, 8 abuts at four abutment points 7 g, 7 g, 8 g, 8 g and the entrance side is latched by the latch 10. Since the contact is made at the single contact point 10g, the catch means 5 does not fall relative to the striker 4.

According to this invention, as shown in FIG. 7A, the two contact points 7g, 7g on the inner surface of the first insertion portion 7a of the base plate 7 that contacts the striker 4 and the inner surface of the first insertion portion 8a of the base plate 8 are provided. Two contact points 8g, 8g and a single contact point 10g that contacts the inner surface of the second fitting portion 10a of the latch 10 are spaced at an interval of 2θ = 120 degrees along the outer periphery of the striker 4. Therefore, the force for gripping the striker 4 is as follows. When a force of 2F ₅ acts on the lower surface of the striker 4 from the latch 10 at the contact point 10g, the force with which the striker 4 is pressed upward to the base plates 7 and 8 is F _{5 that} is 1/2 of 2F _5. Become. This F ₅ is divided into two and becomes a force F ₆ which acts on the tapered surfaces 7f and 8f. Since 2θ = 120 degrees and θ = 60 degrees, F ₆ = F ₅ and the force of F ₅ is pressed against the tapered surfaces 7f and 8f, respectively. Therefore, if the friction coefficient of the contact points 7g, 7g, 8g and 8g is μ, a friction force of μF ₅ acts on the contact points 7g, 7g, 8g and 8g, and a friction force of 2μF ₅ acts on the contact point 10g. Works. Therefore, when the frictional forces generated at the same position in the circumferential direction are added to each other and the frictional forces generated at three locations in the circumferential direction are observed, the frictional forces of the same magnitude of 2 μF ₅ , 2 μF ₅ , and 2 μF ₅ are generated. And a total friction force of 6 μF ₅ is generated. The friction force of 6 μF ₅ prevents the striker 4 from rotating and sliding in the axial direction with respect to the catch means 5. Therefore, the striker 4 is not only held from the three directions on the outer periphery, but also has a gripping force 1.5 times larger than that of the conventional one, and the striker 4 has any of 360 degrees of the outer periphery of the striker 4 with respect to the catch means 5. Even if it tries to move relatively in the direction of

  Conventionally, the latch and the base plate are in contact with the striker 4 one by one, and the striker 4 is in contact with a total of two locations to prevent the striker from rotating and sliding in the axial direction. Since the striker is prevented from rotating and sliding in the axial direction at three locations in the circumferential direction, the striker can be reliably fixed.

  According to this seat fixing device, the striker 4 does not move relative to the catch means 5 in any direction on the outer periphery of the striker 4, and the striker 4 falls over the catch means 5. Since the striker 4 is stably held by the catch means 5, the catch means 5 does not play back or fall relative to the striker 4 even when a large load is applied to the sheet. Support rigidity can be improved. Further, since the striker 4 comes into contact with three locations on the outer periphery, the gripping force is 1.5 times that of the conventional contact with two locations, and the striker 4 rotates relative to the catch means 5 or in the axial direction. Since sliding is suppressed, there is an effect equivalent to increasing the urging force of the cam 14 that pressurizes the latch 10.

  According to the seat fixing device, the striker 4 is supported by the catch means 5 at an equal interval of 360 degrees on the outer periphery of the striker 4, so that the striker 4 is more stably held by the catch means 5.

  In the present embodiment, taper surfaces are formed on both innermost sides of the first insertion portion to set a width dimension smaller than the outer diameter dimension of the striker, but protrusions are provided on both innermost sides of the first insertion portion. And a width dimension smaller than the outer diameter dimension of the striker may be set. Further, although the spring 15 is used as the urging means for urging the latch and the urging means for urging the cam, the springs may be provided separately. Furthermore, although the configuration for fixing the rear seat has been described, it is not limited to the fixing of the rear seat. Further, FIG. 6B illustrates a case where the present invention is applied to a configuration in which a hinge is provided at the front portion of the seat cushion and a catch means 5 is provided at the rear portion and the vehicle body is flipped forward with respect to the vehicle body. The present invention may be applied to a configuration for flipping up and a configuration for storing on a floor surface. Furthermore, although the latch is arranged on the left in FIG. 2 and the lock tooth is arranged on the right with respect to the first insertion portion of the base plate, the arrangement may be reversed.

DESCRIPTION OF SYMBOLS 1 ... Seat 2b ... Car body 3 ... Seat fixing device 4 ... Striker 5 ... Catch means 7, 8 ... Base plate 7a, 8a ... 1st insertion part 7f, 8f ... Tapered surface 7g, 8g, 10g ... Contact point 9 ... Latch shaft DESCRIPTION OF SYMBOLS 10 ... Latch 10a ... 2nd insertion part 11 ... Lock shaft 12 ... Lock plate 12c ... Operation part 13, 15 ... Spring (biasing means)
14 ... Cam

Claims (2)

A striker fixed to the vehicle body and a catch means provided on a seat for catching the striker,
The catch means is
A pair of base plates fixed to the seat;
A first insertion portion that is formed from an outer peripheral portion toward the inside at a substantially intermediate position of each of the base plates and into which the striker enters and exits;
The first insertion portion of the pair of base plates is rotatably provided via a latch shaft that connects the pair of base plates on one side, occupies a lock position and an unlock position, and from the lock position to the unlock position. A latch that is biased to rotate toward
A second insertion portion provided in the latch, in which the striker entering the first insertion portion is inserted and removed;
It is provided rotatably via a lock shaft that connects the pair of base plates to the other side with respect to the first fitting portion of the pair of base plates, and the latch is pivotally biased to move from the lock position to the lock release position. A lock plate that occupies a restraining position for restraining rotation and an allowable position for allowing rotation and is biased to rotate from the permitting position toward the restraining position;
An operation portion formed on the lock plate for manually rotating the lock plate against the rotation bias and rotating the lock plate from the restraining position to the allowable position;
A cam provided rotatably on the lock shaft and biased in a direction to pressurize the latch toward the lock position when the latch occupies the lock position;
In a sheet fixing device comprising:
With the outer peripheral surface of the width of the innermost of the first fitting portion of said each is set smaller than the outer diameter of the striker striker abuts the inner surface and two contact points of the first fitting portion of the respective The sheet fixing device is configured to contact the inner surface of the second insertion portion at a single contact point . The sheet fixing device according to claim 1,
Two contact points where the outer peripheral surface of the striker contacts the inner surface of the first insertion portion of the base plate and a single contact point that contacts the inner surface of the second insertion portion of the latch are the outer periphery of the striker. The sheet fixing device is arranged at substantially equal intervals along the line.

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