JPH0518201Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a locking device for a seat back in a vehicle seat, and is particularly suitable for application to a forward-folding seat.

[Conventional technology]

For example, in a seat installed in a small truck or van-type automobile, the seat bag is folded down so that it overlaps the upper surface of the seat cushion, and the back of the seat bag in the reclined state is used as a storage space for luggage. Various so-called forward-folding seats have been proposed.

The conventional locking device for this forward-folding seat is constructed by disposing a locking member on the upper part of the seat back and providing an engaging part on the vehicle body wall side, and when the seat is used as a normal seat, the locking member is engaged with the engaging part. The seat bag is held locked in an upright position by engaging the lock member, and when the seat bag is to be folded forward, the locking member is removed from the engaging portion, the seat bag is folded forward, and the seat bag is stacked on the upper surface of the seat cushion. The back part of the seat bag in the forward-folded state can be used as a storage space for luggage.

[Problem to be solved by the invention] However, the conventional locking device for forward-folding seats is constructed with members arranged on both the seat back and the vehicle body wall, resulting in a complicated structure and an increase in weight and cost. Furthermore, since the seat back does not lock in any way when it is tilted forward, it may cause the seat back to flap unexpectedly due to vibrations while driving, or when you place luggage on the back of the seat back. However, there were problems such as the seat back tilting due to its weight.

The present invention has been made in view of the above, and an object of the present invention is to provide a locking device that can reliably lock a seat bag in a predetermined position with a simple configuration.

[Means to solve the problem]

In order to achieve the above object, the device of the present invention includes a base plate fixed to the seat cushion.
A four-bar link mechanism in which a rotating plate fixed to the seat back is rotatably mounted in the front-rear direction, and four link members are rotatably connected to each other between the base plate and the rotating plate. Arranged,
One joint of this four-bar linkage mechanism is pivotally connected to the base plate, and the joint opposite to this pivot joint is engaged so as to be movable toward and away from the pivot joint, and serves as an operating section. A pair of engaging portions are symmetrically provided at two joints facing each other between the mounting portion and the operating portion, and an engaging recess into which the pair of engaging portions are engaged is provided on the rotating plate side. A plurality of pairs are provided on the circumference around the shaft attachment part of the plate.

[Effect]

The measures described above operate as follows.

When both engaging parts of the four-bar link mechanism are engaged with the engaging recesses of the rotating plate, the rotating plate is fixed to the base plate without being able to rotate, that is, the seat back is in a locked state, and from this state When the four-bar linkage mechanism is activated by operating the operation part and each link member is rotated, both engaging parts are disengaged from the engaging recesses and the rotating plate is unlocked, and in this state, the seat back is rotated a specified number of times. The seat back can be tilted to the tilted position, and in this tilted position, both engaging portions of the four-bar link mechanism are engaged with other engaging recesses, so that the seat back is again locked at that position.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

In this example, a case will be explained in which the device of the present invention is applied to a forward-folding seat.

In FIG. 2, Sc is a seat cushion fixed to the floor of the vehicle body, Sb is a seat bag, and this seat bag Sb is connected to the seat cushion Sc so that it can be folded forward so as to overlap the upper surface of the seat cushion Sc.

1 is a base plate fixed to the rear end of the side of the seat cushion Sc via a hinge bracket 2; 3 is a rotating plate fixed to the lower end of the side of the seat bag Sb; this rotating plate 3 is attached to the inner surface of the base plate 1; It is pivotally attached to the side via a shaft 4 so as to be rotatable in the front-rear direction.

And this base plate 1 and rotating plate 3
In between, as shown in Figures 1, 3 and 4,
A four-bar link mechanism 5 is provided for locking the rotating plate 3 against the base plate 1 so as not to rotate. This four-bar link mechanism 5 has four link members, namely a first link 6, a second link 7,
The third link 8 and the fourth link 9 are rotatably connected to each other by connecting pins 10, 11, 12, and 13, respectively. link 6 and second link 7, and a third link 8 connected by a connecting pin 12
and the fourth link 9 are formed to have the same length,
In addition, the third link 8 and the fourth link 9 are formed longer than the first link 6 and the second link 7, and the first link 6 and the fourth link 9 are connected to the connecting pin 13. Accordingly, the second link 7 and the third link 8 are connected by a connecting pin 11, respectively.

The four-bar link mechanism 5 configured in this manner has one joint portion thereof, in this example, a joint portion between the first link 6 and the second link 7, which forms a pivot portion 14 that is pivotally connected to the base plate 1. has been done. That is, the connecting pin 10 connecting the first link 6 and the second link 7
is connected to and pivoted to the upper part of the base plate 1, and the four-bar link mechanism 5 is pivotally supported on the base plate 1 side by this connecting pin 10.

Further, a joint between the third link 8 and the fourth link 9 facing the pivoting part 14 is engaged with the base plate 1 so as to be movable in the direction of approaching and separating from the pivoting part 14, and is connected to the operating part 15. has been completed. That is, the connecting pin 12 that connects the third link 8 and the fourth link 9
The distal end thereof is inserted into and engaged with a guide elongated hole 16 bored in the base plate 1. This guide slot 16 is formed so as to be located on an extension of the line connecting the pivot joint 14 of the four-bar link mechanism 5 and the shaft 4, and therefore, the third link 8 and the fourth link 9 are connected to each other. The connecting pin 12 to be connected is engaged with and supported on the pivot portion 14 of the four-bar linkage mechanism 5 with the shaft 4 in between so as to be movable in the approaching and separating directions. , an operating knob 17 is attached to the outer surface of the base plate 1.

Furthermore, there are two opposing joints between the pivot portion 14 and the operating portion 15, namely, the joint between the second link 7 and the third link 8, and the joint between the first link 6 and the fourth link 9. A pair of engaging portions 18 are provided at the joints between the two.
a and 18b are provided symmetrically. That is, in this example, the connecting pin 11 that connects the second link 7 and the third link 8 and the connecting pin 13 that connects the first link 6 and the fourth link 9 protrude toward both the inner and outer sides, respectively. The two connecting pins 1
The inner end portions of 1 and 13 form engaging portions 18a and 18b that are engaged with engaging recesses to be described later.
In addition, the outer ends of both the connecting pins 11 and 13 are engaged with arcuate long guide holes 20a and 20b centered on the pivot portion 14 of the four-bar link mechanism 5 bored in the base plate 1. has been done.

Further, a tension coil spring 21 is stretched between the middle part of the first link 6 and the middle part of the second link 7, and the biasing force of the tension coil spring 21 causes the four-bar link mechanism 5 is always both engaging parts 18
They are biased in the direction in which a and 18b approach each other, that is, in the direction in which they are engaged with an engagement recess described later.

On the other hand, the four-bar link mechanism 5 configured in this way
Correspondingly, an engagement plate body 22 formed in a disc shape is fixed to the rotation plate 3 side with its center aligned with the shaft 4, and on the peripheral edge of this engagement plate body 22, A plurality of pairs of engaging recesses are provided that correspond to the pair of engaging parts 18a and 18b described above. That is, in this example, first engagement recesses 23a, 23b and second engagement recesses 24a, 24b are provided, with which the engagement portions 18a, 18b are engaged, respectively, when the seat bag Sb is in the upright state and in the forward-folded state. There is.

Next, the operation of the apparatus of this example configured as above will be explained.

Now, as shown in FIG. 1A, both engaging portions 18a and 18b of the four-bar linkage mechanism 5
When the seat bag Sb is engaged with the engagement recesses 23a and 23b, the seat bag Sb is held locked in an upright position, and can therefore be used as a normal seat.

From this state, when the operating knob 17 is operated in the direction of arrow a, that is, in the direction approaching the pivot portion 14 of the four-bar linkage mechanism 5, the four-bar linkage mechanism 5 engages both sides against the biasing force of the tension coil spring 21. The portions 18a and 18b operate to separate from each other, so that both the engaging portions 18a, 18b and the first engaging recesses 23a, 23b
is disengaged, the rotating plate 3 becomes freely rotatable relative to the base plate 1 (FIG. 1B), and the seat back Sb is unlocked. When the seat bag Sb is pressed forward, that is, in the direction of lodging in this unlocked state, the seat bag Sb will fall forward and rotate so as to overlap the upper surface of the seat cushion Sc.
At this time, both engaging portions 18a, 1 of the four-bar link mechanism 5
When the operation knob 17 is released, the biasing force of the tension coil spring 21 causes the engagement plate 2 to
When the seat back Sb is brought forward to a substantially horizontal state, both engaging portions 18a and 18b of the four-bar linkage mechanism 5 are simultaneously brought into the second engaging position by the biasing force of the tension coil spring 21. Matching recess 24a, 2
4b, and as a result, the rotating plate 3 is fixed unrotatably to the base plate 1 (FIG. 1C), and the seat back Sb is locked and held in a forward tilted state.

As described above, according to the locking device of this example, the seat back Sb can be reliably locked in the upright state and in the forward-folded state, and in particular, by locking the seat back Sb in the forward-folded state, the seat back Sb can be locked while the vehicle is traveling. There is no chance of the seat bag flopping around unexpectedly or tilting due to the weight of luggage placed on the back of the seat bag Sb. Moreover, this lock consists of a pair of engaging portions 18a and 18b.
Since the locking is performed by two-point engagement between the engagement recesses 23a, 23b or 24a, 24b, the locking strength is increased, and the seat back Sb is more reliably locked.

In addition, this locking device has a simple configuration that uses a four-bar linkage mechanism, so it can be easily incorporated into the connection between the seat cushion Sc and the seat back Sb.
Therefore, the structure is simpler than the conventional one in which a locking mechanism is disposed between the seat back and the vehicle body wall, and the weight and cost can be kept low.

In this example, the four-bar link mechanism 5 having the engaging portions 18a, 18b is pivotally mounted on the base plate 1 side, and the engaging recesses 23a, 2 are provided on the rotating plate 3 side.
3b, 24a, 24b, but the relationship is reversed, that is, the engagement recess 2 is provided on the base plate 1 side.
3a, 23b and 24a, 24b, and the four-bar link mechanism 5 is pivotally mounted on the rotating plate 3 side, the same operation as described above is performed.

In addition, in this example, the joint between the second link 7 and the third link 8 of the four-bar link mechanism 5 and the first link 6
and the fourth link 9, each connecting pin 11
and 13 are used to provide the engaging portions 18a and 18b, but the present invention is not limited to this, and the engaging portions may also be formed by protruding separate engaging members near the two joint portions. good.

In addition, in the configuration of this example, the four-bar link mechanism 5
A compression coil spring is interposed between the first link 6 and the second link 7 in place of the tension coil spring 21 to bias both the engaging portions 18a and 18b in a direction away from each other, and the engagement plate body 22 is formed into a ring shape, and the engaging recesses 23a, 23b and 24a, 24 are engaged with the engaging portions 18a, 18b on the inner circumference thereof.
It may be configured to form b. In this case, the operation knob 17 is operated in a direction away from the pivot portion 14 of the four-bar linkage mechanism 5 to release the lock.

Furthermore, although this example shows an example in which the locking device of the present invention is applied to a forward-folding seat, the present invention is not limited to this forward-folding seat, but can also be applied to, for example, a reclining seat. In this case, the engaging recesses 23a, 23b and 24a, 24b
By providing more pairs of
The slope angle of Sb can be adjusted step by step with fine pitches.

[Effect of idea]

As described above, the locking device of the present invention is configured to lock between the rotating plate and the base plate by engaging the pair of engaging portions with the engaging recessed portions through the operation of the four-bar link mechanism. The seat bag can be reliably locked in a predetermined position, and since this locking is performed by engagement at two points, the pair of engaging parts and the engaging recess, the locking strength is high, and the seat back is more secure. This locking device has a simple structure using a four-bar linkage mechanism, so it has great practical effects, such as being able to keep weight and cost to a minimum.

[Brief explanation of drawings]

Figures 1A to C are partially cutaway side views of the device of the present invention, Figure 2 is a side view of a forward-folding seat equipped with the device of the present invention, Figure 3 is a front view of the device of the present invention, and Figure 4 is a side view of the device of the present invention. It is an exploded perspective view of the same. In the figure, 1 is a base plate, 3 is a rotation plate, 5 is a four-bar link mechanism, 6 is a first link, 7
8 is the second link, 8 is the third link, 9 is the fourth link, 14 is the pivot portion, 15 is the operation portion, 18a,
18b is an engaging portion, 23a and 23b are first engaging recesses, and 24a and 24b are second engaging recesses.

Claims (1)

[Claims for Utility Model Registration] A rotating plate fixed to the seat bag is pivotally attached to a base plate fixed to the seat cushion so as to be rotatable in the front and back direction, and between the base plate and the rotating plate, A four-bar link mechanism is provided in which four link members are rotatably connected to each other, one joint of the four-bar link mechanism is pivotally connected to one of the plates, and a joint opposite to the pivot joint is provided. is engaged to be movable in a direction toward and away from the pivot portion to form an operating portion, and a pair of engagement portions are provided at or near two opposing joint portions between the pivot portion and the operating portion. The coupling portions are provided symmetrically, and the engagement recesses, in which the pair of engagement portions are engaged, are provided on the other plate facing the plate on which the four-bar linkage mechanism is pivotally connected, and the engagement recesses in which the pair of engagement portions are engaged are arranged along the axes of both plates. A plurality of pairs are provided on the circumference around the mounting part, and the four-bar link mechanism is actuated by operation of the operating part, and the engaging part is engaged with the engaging recess to connect the two plates. 1. A locking device for a seat back in a vehicle seat, characterized in that the locking device is configured to lock and release the lock, and lock and hold the seat back at a predetermined position relative to the seat cushion.