JP2001328474A - Tumble lock mechanism for seat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tumble lock mechanism with excellent operability and a function of locking a seat in a seated position. SOLUTION: A front link 11 mounted onto the floor side to support a seat front part rotatably, a lower link 13 with the front end rotatably connected to the front link 11, and a rear link 18 rotatably connected between the rear end of the lower link 13 and the rear part of the seat, are provided to constitute a quadric crank linkage mechanism having a seat side constituent member as an upper link. A hook 21 having a first locking claw 21a and a second locking claw 21b is fitted to the rear link 18. When the seat is in a seated position, the first locking claw 21a is fitted to a striker 23 on the floor side, and when the seat is put in an inverted state, the second locking claw 21b is fitted to a fastening part 25 on the seat side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tumble lock mechanism for a seat that locks an inverted seat in the inverted state by flipping a rear portion of the seat around a front portion of the seat as a center of rotation.

[0002]

2. Description of the Related Art Some rear seats of a vehicle are provided with a mechanism for inverting the seat by flipping up the rear portion of the seat around a front portion of the seat so that the luggage space can be temporarily expanded. .

[0003] This type of seat is usually provided with a tumble lock mechanism for keeping the seat in an inverted state, separately from a seat lock mechanism for locking the seat in a seating position. On the other hand, there has been proposed a type in which a seat lock mechanism is also used as a tumble lock mechanism (for example, Japanese Patent Laid-Open No.
104424).

[0004]

When the tumble lock mechanism is provided separately from the seat lock mechanism as in the former case, not only the space occupied by the lock mechanism is increased, but also the number of parts of the lock mechanism is increased. For this reason, as in the latter case, it is required that the seat lock mechanism is also used as a tumble lock mechanism. By the way, the latter dual-purpose tumble lock mechanism is configured to force the operator to perform a tumble lock operation for locking the seat in the inverted state after the seat is inverted.

However, when the seat is turned upside down,
Since the sheet is heavy, the user often uses both hands to perform the inversion operation of the sheet. Therefore, it is difficult to smoothly perform the tumble lock operation during the inversion operation of the seat, and the conventional tumble lock mechanism has a problem that the operability is poor.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a tumble lock mechanism having a function of locking a seat in a seating position, which is excellent in operability. To provide.

[0007]

According to the first aspect of the present invention,
A front link that is attached to the floor side and rotatably supports the front of the seat in a seat tumble lock mechanism that locks the inverted seat by flipping the rear of the seat around the front of the seat and rotating the rear of the seat. And a lower link having a front end rotatably connected to the front link, and a rear link rotatably connected between a rear end of the lower link and a rear portion of the seat, to provide a seat-side component member. Construct a four-bar rotating chain mechanism that serves as an upper link,
A hook having a first locking claw and a second locking claw is attached to the rear link, and the first locking claw is engaged with a floor-side striker when the seat is in a seating position.
The second lock claw is engaged with the engaging portion on the seat side when the seat is in an inverted state.

According to the present invention, when the hook is displaced by the four-bar rotation chain mechanism and the seat is in the seating position, the first locking claw of the hook engages with the striker on the floor side, and when the seat is inverted, the hook is hooked. Is engaged with the engaging portion on the seat side. Therefore, the seat can be locked at the seating position or locked at the inverted position using the same hook, and the function of locking the seat at the seating position can be provided to the tumble lock mechanism.

According to the present invention, the first lock claw and the second lock claw of the hook automatically come close to and engage with the floor side striker and the seat side engagement portion by the four-bar rotation chain mechanism. After the seat is turned upside down, the operator is not forced to perform a tumble lock operation for locking the seat in this upside down state, and the operability is excellent.

According to a second aspect of the present invention, in the first or second aspect of the present invention, the hook is such that the first lock claw and the second lock claw are centered on a connecting point between the rear link and the lower link. The lock is attached to the rear link so that it can be unlocked by rotating in the same direction from the reference position, and is always locked by a spring so that the first lock claw and the second lock claw can return to the reference position. When the seat is moved to the seating position, the outer peripheral portion of the first lock claw at the reference position is pressed against the striker when the seat is moved to the seating position. The first lock claw is rotated once in the unlocking direction against the urging force of the spring, and then rotated in the reference position direction by the urging force of the spring. The engagement between the second lock claw and the locking portion is performed by pressing an outer peripheral portion of the second lock claw at the reference position against the locking portion when the sheet is moved to an inverted state. The second force against the urging force of the spring;
This is achieved by rotating the lock claw once in the unlocking direction and then rotating the lock claw in the reference position direction by the urging force of the spring.

According to the present invention, the rotation directions of the first lock claw and the second lock claw at the time of unlocking are made to coincide with each other, and when shifting from the sitting position to the inverted state, or vice versa, when shifting from the inverted state to the sitting position. Since the lock can be released only by rotating the hook in one direction, the operability is further improved. In addition, since the connection point between the rear link and the lower link coincides with the center of rotation of the hook, it is easy to attach the hook to the rear link.

According to a third aspect of the present invention, in the first or second aspect of the invention, the four-bar rotating chain mechanism is constituted by a parallel crank mechanism. In the present invention, since the upper link is constituted by the seat-side components using the parallel crank mechanism, the turning radius of the front portion of the seat during the inversion operation of the seat can be reduced, and the seat is excessively turned when the seat is inverted. It does not protrude forward and come into contact with the front seat or the like.

According to a fourth aspect of the present invention, in the first or second aspect, a straight line connecting a connecting point between the front link of the seat and the front link and a connecting point of the rear link of the seat and the rear link is: The four-bar rotating chain mechanism is configured to intersect a straight line connecting a connection point at a front end and a connection point at a rear end of the lower link.

According to the present invention, the turning radius of the front portion of the seat when the seat is turned over can be increased. Therefore, in a vehicle in which the seat can be moved forward when the seat is turned over, the space behind the seat (load) can be reduced. Room etc.) can be enlarged.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of the present invention will be described with reference to FIGS.
The left side in FIG. 1 is the front side. 1 to 3
1, the seat track 1 has a lower rail 2 and an upper rail 4 which is fitted to the lower rail 2 via a plurality of balls 3 and is slidable in the longitudinal direction of the lower rail 2. The upper rail 4 is attached to a seat cushion frame of a seat (not shown) using a bolt or the like protruding from the upper rail 4. Although not shown, the seat track 1 is also provided with a lock mechanism for locking the upper rail 4 so as not to slide on the lower rail 2.

A front bracket 7 and a rear bracket 8, each having a substantially U-shaped cross section, are fixed to the lower surface on the front side and the rear side of the lower rail 2 by, for example, tacking, fastening or welding. In the present embodiment, not only the seat track 1 but also the front bracket 7 and the rear bracket 8 constitute a part of the inverted seat.

A front link 11 having a substantially U-shaped cross section is mounted on the floor side and rotatably supports a front bracket 7 which is a front portion of a seat via a pin 12. The front link 11 has a cross section. Is a substantially U-shaped lower link 13
Is rotatably connected via a pin 14. A rear link 18 having a substantially U-shaped cross section is rotatably connected between a rear end of the lower link 13 and a rear bracket 8 serving as a rear portion of the seat via pins 16 and 17, respectively. The pin 16 has an oval section 1
6a are formed, which are the lower link 13 and the rear link 1.
8, the fitting holes are circular, and the lower link 13 and the rear link 18 are rotatable with respect to the oval section 16a.

The front bracket 7, the rear bracket 8, and the lower rail 2, which are the components on the seat side, are integrally connected to form an upper link. The front link 11, the lower link 13 and the rear link 18 constitute a four-bar rotating chain mechanism. In the present embodiment,
The distance between pins 12 and 17 and the distance between pins 14 and 16 are equal, and the distance between pins 12 and 14 and pin 17
-The distance between the pins 16 is equally selected, and the four-bar rotating chain mechanism constitutes a parallel crank mechanism.

First lock claw 21a and second lock claw 21
The hook 21 having a substantially U-shaped cross section and having a b is formed such that the first lock claw 21a and the second lock claw 21b are respectively positioned from a reference position around a connection point (pin 16) between the rear link 18 and the lower link 13. The rear link 18 is rotated in the same direction (clockwise in FIG. 1) so that the lock can be released.
(Pin 16). Here, the reference position is a position where the hook 21 is rotated by the maximum amount in the locking direction and the rotation is restricted. In the present embodiment,
As shown in FIG. 1, the protrusion 21 c of the hook 21 is in a position where the rotation is restricted by contact with the wall surface of the rear link 18.

The first lock claw 21a of the hook 21 engages the striker 23 on the floor side when the seat is at the seating position (the position indicated by the solid line in FIG. 1). To do, striker 2
Three entry grooves 18a are formed. Here, as shown in FIG. 3 and the like, the striker 23 is formed by bending a columnar bar into a substantially U-shape, and is fixed in a recess formed in the floor. The second lock claw 21b engages with a pin 25 protruding from the rear bracket 8, which is a seat-side engaging portion, when the seat is in an inverted state (the position indicated by the two-dot chain line in FIG. 1). .

The pin 16 and the hook 21 rotate integrally. In this embodiment, the fitting hole of the hook 21 with respect to the oval section 16a of the pin 16 matches the oval section 16a. It has an oval shape. Further, a torsion coil spring 27 is inserted into one end of the pin 16 on which the slit 16b is formed.
a is hooked on the slot 16b, and an outer end (not shown) is hooked on the rear link 18.

The first lock claw 21a and the second lock claw 21b are always urged in the locking direction by the spring 27 so that they can return to the reference position.
When the seat is moved to the seating position, the outer peripheral portion of the first lock claw 21a at the reference position is pressed against the striker 23 when the seat is moved to the seating position. The second lock claw 21b can be achieved by rotating the lock claw 21a once in the unlocking direction and then rotating the lock claw 21a in the reference position direction by the urging force of the spring 27.
Is engaged with the pin 25 when the sheet is moved to the inverted state.
The outer peripheral portion of the second lock claw 21b at the reference position is
By rotating the second lock pawl 21b once in the unlocking direction once against the urging force of the spring 27, the urging force of the spring 27 is rotated toward the reference position.

The other end of the pin 16 has an unlocking handle 2
9 are connected. This unlock handle 2
Numeral 9 is for releasing the engagement between the first lock claw 21a and the striker 23 and the engagement between the second lock claw 21b and the pin 25.

Next, the operation of the above embodiment will be described.
First, in the seated state, the striker 23 is connected to the rear link 18.
And the first lock claw 21a of the hook 21 is engaged with the striker 23 on the floor side. Therefore, the rear portion of the seat cannot be flipped up.

In this state, the lock release handle 29 is operated, and the first lock claw 2 is pressed against the urging force of the spring 27.
When the lock 1a is rotated in the unlocking direction (clockwise direction in FIG. 1) to release the engagement between the first lock claw 21a and the striker 23, the rear portion of the seat can be flipped up around the pin 12 at the front portion of the seat. When the rear portion of the seat is raised centering on the pin 12, the rear link 18 is also pulled up because the rear bracket 8 and the rear link 18 are connected by the pin 17.

Here, the rear link 18 constitutes a part of the parallel crank mechanism, and its posture (inclination) does not change even if it rises. For this reason, the hook 21 also rises while maintaining that posture. At this time, the first lock claw 21a and the second lock claw 21b of the hook 21 are at the reference position.

When the sheet approaches the inverted state, the outer peripheral portion of the second lock claw 21b at the reference position comes into contact with the pin 25, and the outer peripheral portion of the second lock claw 21b is pressed by the pin 25. For this reason, the second lock claw 21b once escapes in the unlocking direction against the urging force of the spring 27, and further rotates the seat, so that the pin 25 enters the groove of the second lock claw 21b. Thereby, the second lock claw 2
1b is rotated in the direction of the reference position by the urging force of the spring 27, and the second lock claw 21b is engaged with the pin 25 (the position indicated by the two-dot chain line in FIG. 1). In this state, the second lock claw 21b and the pin 25 cannot be displaced in the direction in which they are separated from each other, the movement of the parallel crank mechanism is restricted, and the seat is locked in the inverted state.

To return the seat from the inverted state to the seated state, the unlocking handle is operated in exactly the same direction as when flipping up, and the second lock claw 21b is released in the unlocking direction against the urging force of the spring 27. (Clockwise direction in FIG. 1)
To release the engagement between the second lock claw 21b and the pin 25. Thus, the rear portion of the seat can be lowered around the pin 12 at the front portion of the seat. When the rear portion of the seat is lowered around the pin 12, the rear link 18 is also lowered. Therefore, the hook 21 descends while maintaining the posture. The first lock claw 2 of the hook 21 at this time
1a and the 2nd lock claw 21b are in a reference position.

When the seat approaches the seated state, the outer peripheral portion of the first lock claw 21a at the reference position comes into contact with the striker 23, and the outer peripheral portion of the first lock claw 21a comes into contact with the striker 23.
Is pressed. Therefore, the first lock claw 21a once escapes in the unlocking direction against the urging force of the spring 27,
When the seat further rotates and is seated, striker 2
3 enters the groove of the first lock claw 21a. Thus, the first lock claw 21a is rotated in the direction of the reference position by the urging force of the spring 27, and the first lock claw 21a is engaged with the striker 23 (solid line position in FIG. 1). In this state, the first lock claw 21a and the striker 23 cannot be displaced in a direction in which they are separated from each other, the movement of the parallel crank mechanism is restricted, and the seat is locked again in the seated state.

In the present embodiment, when the hook 21 is displaced by the four-bar rotating chain mechanism and the seat is in the seating position, the first lock claw 21a of the hook 21 engages the striker 23 on the floor side, and Is in an inverted state, the second lock claw 21b of the hook 21 is engaged with the pin 25, which is a hook on the seat side. Therefore, the seat can be locked at the seating position or locked at the inverted position using the same hook 21, and the function of locking the seat at the seating position can be provided to the tumble lock mechanism.

In this embodiment, the first lock claw 21a and the second lock claw 21b of the hook 21 are connected to the floor side striker 23 and the pin serving as a seat side hooking section by a four-bar rotating chain mechanism. Since the seat 25 is automatically approached and engaged therewith, after the seat is turned upside down, the operator is not forced to perform a tumble lock operation to lock the seat in this inverted state, and the operability is excellent.

Further, in the present embodiment, the rotation direction of the first lock claw 21a and the second lock claw 21b of the hook 21 at the time of unlocking is made to coincide with the clockwise direction in FIG. At the time of the transition or the reverse of the inverted state to the seating position, the lock can be released only by rotating the hook 21 in one direction (clockwise direction in FIG. 1). The sex is even better.

Further, since the hook 21 is configured to rotate around the pin 16 which is a connection point between the rear link 18 and the lower link 13, the rear link 18 of the hook 21 is rotated.
The pin 16 can also be used for attachment to the device, which facilitates attachment. Further, in the present embodiment, the parallel link mechanism is used as the four-bar rotating chain mechanism, and the upper link thereof is constituted by the member on the seat side. (R in FIG. 1) can be reduced, and the sheet does not protrude excessively forward when the sheet is inverted and does not come into contact with the front sheet or the like.

The above embodiment can be variously modified. For example, the front bracket 7 and the rear bracket 8 may be formed integrally, and may be used as the upper link of the parallel crank mechanism. Further, it is not always necessary to dispose the hook 21 at the connection point between the rear link 18 and the lower link 13, and the hook 21 may be provided at another position on the rear link 18. Further, it goes without saying that the tumble lock mechanism can be used for a seat having no seat track. In this case, the front bracket 7 and the rear bracket 8 are directly fixed to the seat cushion frame, and the front bracket 7, the rear bracket 8 and the seat cushion frame constitute an upper link of the parallel crank mechanism.

(Second Embodiment) A second embodiment of the present invention will be described with reference to FIGS. The left side in FIG. 4 is the front side. 4 to 6,
The seat track 51 has exactly the same configuration as the seat track 51 in the first embodiment, and includes a lower rail 52 and a plurality of balls 5 mounted on the lower rail 52.
3 and an upper rail 54 slidable in the longitudinal direction of the lower rail 52. Upper rail 5
4 is attached to a seat cushion frame of a seat (not shown) using bolts or the like protruding from the upper rail 54. Although not shown, the seat track 51
Is also provided with a lock mechanism for locking the upper rail 54 so as not to slide with respect to the lower rail 52.

A bracket 57 extending from the front side to the rear side is fixed to the lower surface of the lower rail 52 by, for example, tacking, fastening or welding. Bracket 5
The cross-section of 7 is substantially L-shaped on the front side, but is substantially U-shaped on the rear side. In the present embodiment, not only the seat track 51 but also the bracket 5
7 also constitutes a part of the inverted sheet.

A front link 61 having a substantially L-shaped cross section is attached to the floor, and a bracket 57 at the front of the seat is provided.
Is rotatably supported via a pin 62,
A front end of a plate-like lower link 63 is rotatably connected to the front link 61 via a pin 64. A rear link 68 having a substantially U-shaped cross section is rotatably connected via a pin 66 and a pin 67 between the rear end of the lower link 63 and the rear portion of the bracket 57 that is the rear of the seat. The pin 66 has an oval section 66a.
The lower link 63 and the rear link 68 are fitted with the respective holes of the lower link 63 and the rear link 68, and the fitting holes are circular. It is rotatable.

Bracket 57 as a component on the seat side
Constitutes an upper link, a front link 61 and a lower link 6
Together with the third and rear links 68, a four-bar rotating chain mechanism is formed. In the present embodiment, the distance between the pins 62 and 67 is larger than the distance between the pins 64 and 66, and the distance between the pins 62 and 64 is selected to be larger than the distance between the pins 67 and 66. I have. Then, a straight line connecting the connection point (pin 62) between the front part of the seat and the front link 61 and the connection point (pin 67) between the rear part of the seat and the rear link 68 is
The lower link 63 is arranged so as to intersect with a straight line connecting the connection point (pin 64) at the front end and the connection point (pin 66) at the rear end.

The first lock claw 71a and the second lock claw 71
The hook 71 having a substantially U-shaped cross section and having a b is formed such that the first lock claw 71a and the second lock claw 71b are respectively positioned from a reference position around a connection point (pin 66) between the rear link 68 and the lower link 63. The rear link 6 is rotated in the same direction (counterclockwise in FIG. 4) so that the lock can be released.
8 (pin 66). Here, the reference position is a position when the hook 71 is rotated by the maximum amount in the locking direction and the rotation is restricted. In the present embodiment, as shown in FIG. Reference numeral 71c denotes a position where the rotation is restricted by abutting against the wall surface of the rear link 68.

The first lock claw 71a of the hook 71 engages with the striker 73 on the floor side when the seat is at the seating position (the position indicated by the solid line in FIG. 4). To strike, striker 7
Three entry grooves 68a are formed. Here, the striker 73 is exactly the same as the striker 23 and is fixed in a recess formed on the floor. The second lock pawl 71b engages with a pin 75 projecting from the rear of the bracket 57, which is a seat-side engaging portion, when the seat is in an inverted state (the position indicated by the two-dot chain line in FIG. 4). is there.

The pin 66 and the hook 71 rotate integrally, and in this embodiment, the fitting hole of the hook 71 with the oval section 66a of the pin 66 matches the oval section 66a. It has an oval shape. A torsion coil spring 77 is inserted into one end of the pin 66 on which the slot 66b is formed.
a is hooked on the slot 66b, and an outer end (not shown) is hooked on the rear link 68.

The first lock claw 71a and the second lock claw 71b are always urged in the locking direction by the spring 77 so that they can return to the reference position.
When the seat is moved to the seating position, the outer peripheral portion of the first lock claw 71a at the reference position is pressed against the striker 73 when the seat is moved to the seating position. This can be achieved by rotating the lock claw 71a once in the unlocking direction and then rotating the lock claw 71a in the reference position direction by the urging force of the spring 77.
Is engaged with the pin 75 when the sheet is moved to the inverted state.
The outer peripheral portion of the second lock claw 71b at the reference position is
By rotating the second lock claw 71b once in the unlocking direction against the urging force of the spring 77, the urging force of the spring 77 rotates in the reference position direction.

The other end of the pin 66 has an unlocking handle 7
9 are connected. This lock release handle 7
Numeral 9 is for releasing the engagement between the first lock claw 71a and the striker 73 and the engagement between the second lock claw 71b and the pin 75.

Next, the operation of the above embodiment will be described.
First, in the seated state, the striker 73 is connected to the rear link 68.
And the first lock claw 71a of the hook 71 is engaged with the striker 73 on the floor side. Therefore, the rear portion of the seat cannot be flipped up.

In this state, the lock release handle 79 is operated, and the first lock pawl 7 is pressed against the urging force of the spring 77.
When 1a is rotated in the unlocking direction (counterclockwise in FIG. 4) to release the engagement between the first lock claw 71a and the striker 73, the rear portion of the seat can be flipped up around the pin 62 at the front portion of the seat. . Pin 62 at the rear of the seat
, The rear link 68 is also pulled up because the rear portion of the bracket 57 and the rear link 68 are connected by the pin 67.

Here, the rear link 68 constitutes a part of the four-bar rotating chain mechanism. As the link rises, it rotates around the pin 67 in the counterclockwise direction in FIG. Ascends while rotating in the same direction as one. When the sheet approaches the inverted state, the outer peripheral portion of the second lock claw 71b at the reference position comes into contact with the pin 75, and the outer peripheral portion of the second lock claw 71b is pressed by the pin 75. Therefore, the second force against the urging force of the spring 77 is
When the lock claw 71b once escapes in the unlocking direction, and the seat further rotates to be in an inverted state, the pin 75 enters the groove of the second lock claw 71b.

As a result, the second lock pawl 71b is rotated in the direction of the reference position by the urging force of the spring 77, and
The lock claw 71b engages with the pin 75 (the position indicated by the two-dot chain line in FIG. 4). In this state, the second lock claw 71b and the pin 75 cannot be displaced in the direction in which they are separated from each other, so that the movement of the four-bar rotating chain mechanism is restricted, and the seat is locked in the inverted state.

In order to return the seat from the inverted state to the seated state, the lock release handle is operated in exactly the same direction as when flipping up, and the second lock claw 71b is released in the lock release direction against the urging force of the spring 77. (Counterclockwise direction in FIG. 4) to release the engagement between the second lock claw 71b and the pin 75. As a result, the pin 6 at the front of the seat
The rear portion of the seat can be lowered around the center 2. When the rear portion of the seat is lowered about the pin 62, the rear link 68 is lowered while rotating about the pin 67. Therefore, the hook 71 also descends while rotating.

When the seat approaches the seated state, the outer peripheral portion of the first lock claw 71a at the reference position comes into contact with the striker 73, and the outer peripheral portion of the first lock claw 71a comes into contact with the striker 73.
Is pressed. Therefore, the first lock claw 71a once escapes in the unlocking direction against the urging force of the spring 77,
When the seat further rotates and is seated, the striker 7
3 enters the groove of the first lock claw 71a. Thereby, the first lock claw 71a is rotated in the direction of the reference position by the urging force of the spring 77, and the first lock claw 71a is engaged with the striker 73 (the solid line position in FIG. 4). In this state, the first lock claw 71a and the striker 73 cannot be displaced in a direction in which they are separated from each other, and the movement of the four-bar rotating chain mechanism is restricted, and the seat is locked again in the seated state.

As in the case of the first embodiment, also in this embodiment, the hook 7 is driven by the four-bar rotating chain mechanism.
When the seat 1 is displaced and the seat is in the seating position, the hook 7
When the first lock claw 71a of the first hook engages with the striker 73 on the floor side, and the seat is turned upside down, the second lock claw 71b of the hook 71 is a pin 75 serving as a hook on the seat side.
Hang up with. Therefore, the seat can be locked at the seating position or the inverted position by using the same hook 71, and the function of locking the seat at the seating position can be provided to the tumble lock mechanism.

Also in the present embodiment, the first lock pawl 71a and the second lock pawl 71b of the hook 71 are connected to the floor side striker 73 and the pin as the seat side hook by the four-bar rotating chain mechanism. Since the seat 75 is automatically approached and engaged, the operator does not have to perform a tumble lock operation to lock the seat in the inverted state after the seat is turned upside down, so that the operability is excellent.

Further, in the present embodiment, the rotation direction of the first lock claw 71a and the second lock claw 71b of the hook 71 at the time of unlocking is made to coincide with the counterclockwise direction in FIG. The lock can be released only by rotating the hook 71 in one direction (counterclockwise direction in FIG. 4) at the time of shifting from the inverted state to the seating position, so that the operator is not lost. The operability is much better.

Further, since the hook 71 is configured to rotate around the pin 66 which is a connection point between the rear link 68 and the lower link 63, the rear link 68 of the hook 71 is formed.
The pin 66 can also be used for attachment to the device, and the attachment is easy.

In this embodiment, since the pins 62 can be arranged at a low position, the turning radius of the front portion of the seat (the pin 62 is the center of rotation) during the inversion operation of the seat can be increased.
For this reason, in a vehicle that does not hinder the movement of the seat forward when the seat is inverted, the seat is configured to move forward when compared with the first embodiment when the seat is inverted.
It is possible to increase the space behind the seat (such as a luggage compartment).

The present embodiment can be modified in various ways as in the case of the first embodiment. For example, it is not always necessary to arrange the hook 71 at the connection point between the rear link 68 and the lower link 63, and the hook 71 may be provided at another position on the rear link 68. Furthermore,
Needless to say, the tumble lock mechanism can be used for a seat having no seat track.

The present invention is not limited to the above-described two embodiments and modifications. In particular, the four-bar rotating chain mechanism
Various configurations are possible. As the four-bar rotation chain mechanism, the seating position of the seat and the inverted state can be taken,
What is necessary is just to be able to lock in the seating position and the inverted state.

Further, the tumble lock mechanism according to the present invention
The present invention can also be applied to a seat of a type that can be detached from a vehicle floor (so-called detachable sheet). In the case of the detachable sheet, in the case of the configuration of the above embodiment, for example, the front link (1
1, 61) can be detached from the floor of the vehicle.

[0058]

As described above, according to the first to fourth aspects of the present invention, when the hook is displaced by the four-bar rotating mechanism and the seat is in the seating position, the first locking claw of the hook is set on the floor. When the seat is turned upside down, the second lock claw of the hook engages with the hook on the seat side, so the same hook can be used to lock the seat to the seating position or to move the seat to the inverted position. The tumble lock mechanism can be locked and has a function of locking the seat at the seating position.

Further, the first lock claw and the second lock claw of the hook automatically come close to and engage with the striker on the floor side and the hook on the seat side by the four-bar rotating chain mechanism. After setting the state, the operator is not forced to perform a tumble lock operation for locking the seat in the inverted state, so that the operability is excellent.

In particular, according to the second aspect of the present invention, the first
The rotation direction of the lock claw and the second lock claw at the time of unlocking are made to coincide with each other, and only when rotating from the sitting position to the inverted state or vice versa from the inverted state to the sitting position, the hook is simply rotated in one direction. Can be unlocked with
Operability will be much better. In addition, since the connection point between the rear link and the lower link coincides with the rotation center of the hook, the hook can be easily attached to the rear link.

Further, according to the third aspect of the present invention, since the parallel link mechanism is used and the upper link thereof is constituted by the member on the seat side, the turning radius of the front portion of the seat when the seat is turned over is reduced. The sheet can be made smaller, and the sheet does not excessively protrude forward when the sheet is inverted, and does not come into contact with the front sheet or the like.

According to the fourth aspect of the present invention, the turning radius of the front portion of the seat can be increased when the seat is turned over. Therefore, in a vehicle where the seat can be moved forward when the seat is turned over, there is no problem. Space behind seats (luggage room, etc.)
Can be widened.

[Brief description of the drawings]

FIG. 1 is a side view (a cross-sectional view taken along the line AA in FIG. 2) of a first embodiment of the present invention in which a near side portion is broken.

FIG. 2 is an enlarged sectional view taken along a cutting line BB in FIG.

FIG. 3 is an enlarged sectional view taken along a cutting line CC in FIG. 1;

FIG. 4 is a side view (a cross-sectional view taken along the line DD in FIG. 5) of the second embodiment of the present invention, in which a front portion is cut away.

FIG. 5 is an enlarged sectional view taken along a cutting line EE in FIG. 4;

FIG. 6 is an enlarged sectional view taken along a cutting line FF in FIG. 4; It is.

[Explanation of symbols]

1,51 seat track 2,52 lower rail 7 front bracket 8 rear bracket 11,61 front link 12,14,16,17,62,64,66,67
Pins 13, 63 Lower link 16a, 66a Oval cross section 18, 68 Rear link 21, 71 Hook 21a, 71a First lock claw 21b, 71b Second lock claw 21c, 71c Convex portion 23, 73 Striker 25, 75 Pin ( Hanging part) 27, 77 Torsion coil spring 29, 79 Lock release handle 57 Bracket

Claims (4)

[Claims] 1. A seat tumble lock mechanism that locks an inverted seat in an inverted state by flipping up a rear portion of the seat around a front portion of the seat as a center of rotation. A front link rotatably connected to the front link, a lower link having a front end rotatably connected to the front link, and a rear link rotatably connected between a rear end of the lower link and a rear portion of the seat. A hook having a first locking claw and a second locking claw is attached to the rear link, and the first link is provided when the seat is in a seating position. Hook the lock claw on the striker on the floor side,
A tumble lock mechanism for a seat, wherein the second lock claw is engaged with a hook on the seat side when the seat is in an inverted state. 2. The hook is configured such that the first lock claw and the second lock claw can be unlocked by rotating in the same direction from a reference position around a connection point between the rear link and the lower link, respectively. The first lock claw and the striker are attached to the rear link, and are always urged by a spring in a locking direction so that the first lock claw and the second lock claw can return to the reference position. When the seat is moved to the seating position, the outer peripheral portion of the first lock claw at the reference position is pressed against the striker, whereby the first lock claw is pressed against the urging force of the spring. Is rotated once in the unlocking direction, and then rotated in the reference position direction by the biasing force of the spring. Engagement of the second lock claw and the locking portion is achieved by seating the seat. At the time of shifting to the upright state, the outer peripheral portion of the second lock claw at the reference position is pressed against the locking portion, so that the second lock claw is once unlocked against the urging force of the spring. 2. The seat tumble lock mechanism according to claim 1, wherein the rotation is made in the direction of the reference position by the biasing force of the spring. 3. The tumble lock mechanism for a seat according to claim 1, wherein said four-bar rotation chain mechanism is constituted by a parallel crank mechanism. 4. A straight line connecting a connecting point between the front link of the seat and the front link and a connecting point between the rear link of the seat and the rear link is defined as a connecting point of a front end and a connecting point of a rear end of the lower link. 3. The tumble lock mechanism for a seat according to claim 1, wherein the four-bar rotating chain mechanism is configured to intersect a connecting straight line.