GB2234288A

GB2234288A - Reclining seat device

Info

Publication number: GB2234288A
Application number: GB9016252A
Authority: GB
Inventors: Yukifumi Yamada; Keiichi Hibino; Takami Terada; Hisayoshi Chiba
Original assignee: Aisin Seiki Co Ltd
Current assignee: Aisin Corp
Priority date: 1989-07-28
Filing date: 1990-07-25
Publication date: 1991-01-30
Anticipated expiration: 2010-07-25
Also published as: JPH0329033U; GB2234288B; DE4023653A1; JPH0741390Y2; GB9016252D0

Abstract

In a vehicle front seat which can be adjusted manually to a comfortable reclining angle and can also be inclined forwards so that rear seat passengers may get in or out of the vehicle the seat-back on returning to a reclining position is made to adopt a suitable angle by means 23, 24 which hold the pawl 8 en the lower bracket 2 of the seat in a position disengaged from the ratchet 6 on the seat back bracket 5 after the seat back has been tipped forward to a certain position and which allow re-engagement of the ratchet and paw when the seat-back is returned to the suitable reclining angle. The means comprise a shield member 23 pivoted on the main pivot 3 and adapted, on engaging a projection 25 on the bracket 5 when the latter is tipped forwards, to engage a shoulder 22 on the paw where it is retained by resilient means 24. A further projection 26 releases the member 23 when the seat back returns. <IMAGE>

Description

ki 1 - TITLE. Reclining Seat Device

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a reclininq seat and in particular to a reclining seat device for use in an automotive vehicle or the like.

Description of the prior art

Sometimes a seat-back of a front seat is inclined in the forward direction when a passenger on a rear seat is going to getoutof avehicle. Thereafter-, when another passenger sits on the front seat, he/she must return the seat-back to its original position.

However, during the returning movement of the seatback, the seat-back is locked at a position before it is returned to the original position. So, he/she must unlock the seat-back. The foregoing locked condition of the seat-back interrupts the smooth operation thereof and the unlocking operation is cumbersome.

SUMMARY OF THE INVENTION

It is, therefore, a primary object of the present invention to provide a reclining seat device without the 1 aforementioned drawbacks.

A reclining seat device comprises a lower bracket; an upper bracket rotatably connected to the lower bracket by a pin; a ratchet secured to the upper bracket; a pawl connected to the lower bracket and biased towards engagement with the ratchet to prevent rotation of the upper bracket; a handle operable to engage or disengage the ratchet and pawl; means for preventing engagement of the ratchet and pawl when the upper bracket is in a forwardly inclined position; and means for causing reengagement of the ratchet and pawl when the upper bracket is rotated back through a fixed angle from the forwardly inclined position.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the present invention will become more apparent and more readily appreciated from the following detailed description of preferred exemplary embodiments of the present invention, taken in connection with the accompanying drawings, in which:

Fig. 1 is a side view of a reclining seat device; Fig. 2 is a side view illustrating the mechanism of the device in Fig. 1 Fig. 3 and Fig. 4 are views for illustrating the operation of the reclining seat device in Fig. 1; Fig. 5 is a cross-sectional view taken along line V-V in Fig. 2; and Fig. 6 is a cross-sectional view taken along line Vl-Vl in Fig. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring first to Fig. 1, a pair of lower brackets 2 (only one is shown) are secured to opposed rear sides of a seat cushion 1 and each of the lower brackets 2 is pivoted, by a pin 3, to an upper bracket 5 which is fixedly connected to a lower portion of a seat-back 4.

J A.

As illustrated in Figs.2 to 6,a lower portion of the upper bracket 5 is secured, by a rivet 7, to a ratchet 6 which is provided at its lower portion with a geared portion 6a. The lower bracket 2 is pivoted, by a pin 9, with a pawl 8 having a geared portion 8a which is engageable with the geared portion 6a of the ratchet 6. On the pin 3, there are rotatably mounted an operating handle 10 and a cam plate 11, between which a roller 12 is retained on a pin 13. The roller 13 keeps engagement between the ratchet 6 and the pawl 8 by engaging a cam surf ace 8b on a portion of the pawl 8 f acing away f rom the geared portion 8a. The roller 12 moves in or out of engagement with the cam surf ace 8b of the pawl 8 upon rotation of the cam plate 11. A shaft 14 is fixed to the pawl 8 and passes through a cam hole 16 in the cam plate 11, having an inner surface curved for bringing the pawl 8 into or out of engagement with the ratchet 6. The pin 13 and the shaft 14 are extended into a guide slot 17.

Around the pin 3, there is arranged a spiral spring 18, the ends of which are connected respectively to the pin 3 and the upper bracket 5, so as to bias the upper bracket 5 in the clockwise direction in Fig. 2. Between the handle 10 and the lower bracket 2, there is provided a tension spring 19 which urges the handle 10 clockwise in Fig. 2 to effect the engagement of the roller 12 with the cam surf ace 8b of the pawl 8. In addition, the area of engagement between the ratchet 6 and the pawl 8 is covered by a sub-plate 21 which is secured to the lower bracket 2 by a pin 20 and surrounds the pins 3 and 9.

As apparent from Figs. 2 to 4, the p ' awl 8 has a shoulder 22. A shield member 23 the pin to be engageable, upon the shoulder 22 of the pawl 8.

the pawl 8 and the shield disengagement between the pawl 8 the pin 20, an elastic member 24 is rotatably mounted on rotation thereof, with Such engagement between member 23 maintains and the ratchet 6. On is mounted. The elastic 4 - C member 24 engages an abutting portion 23a of the shield member 23, preventing the shield member 23 from being rotated.

on the upper bracket 5, there are provided two spaced projections 25 and 26 in the plane of the shield member 23. For transmitting the rotation of the upper bracket 5 to the shield member 23, the projections 25 and 26 are engageable respectively with faces 23b and 23c of the shield member 23. The projection 25 is brought into engagement with the portion 23b upon rotation of the upper bracket 5 during forward inclination of the seat-back 4, with the result that the shield member 23 rotates to engage the shoulder 22 of the pawl 8. The projection 25 is so positioned that the shield member 23 does not become engaged with the shoulder 22 of the pawl 8 in ordinary reclining positions of the seat-back 4, which range between positions A and B shown in Fig. 1.

operation of the device will now be described. In Fig. 2 rotational movement of the upper bracket 5, attached to the seat-back 4, is prevented owing to the engagement between the ratchet 6 and the pawl 8. When the handle 10 is rotated in the anti-clockwise direction in Fig. 2 against the urging force of the tension spring 19, the cam plate 11 is rotated together with thehandle 10. As a result of the rotation the roller 12 is brought out of engagement with the cam surf ace 8b and the cam hole 16 is moved so as to act on the shaft 14. Thus, the ratchet 6 is released from the pawl 8 and the upper bracket 5 becomes free to rotate. As a consequence, the reclining seat-back 4 can be set at any angle between position A and position B, both of which are shown in Fig. 1. When the handle 10 is released after adjustment of the reclining angle of the seat-back 4, it is returned to its original position by the urging force of the tension spring 19, with the result that the ratchet 6 and the roller 12 are brought into engagement with the pawl 8 and the cam surface 8b respectively. Thus, the upper bracket 5 becomes immovable and the seat-back 4 is X f.

I 1 locked at the adjusted position.

When the handle 10 has been manipulated to bring the ratchet 6 out of engagement with the pawl 8 the seat-back 4 may be brought into a forwardly inclined position c as he upper bracket 5,is rotated in the clockwise direction in Fig. 2 by the urging force of the spiral spring 18. The projection 25 then comes into engagement with the portion 23b, thereby transmitting the rotation of the upper bracket 5 to the shield member 23. Then, as shown in Fig. 3, the shield member 23 engages the shoulder 22, thereby maintaining the released conditionof the ratchet 6 from the pawl 8. At this time, the shield member 23 is prevented from being rotated by the frictional force between the portion 23a and the elastic member 24, which are in elastic engagement. Thereafter, when the seatback 4 and the upper bracket 5 are rotated in the anticlockwise direction in Fig. 3 against the urging force of the spiral spring 18, the projection 26 comes into engagement with the surface 23c, with the result that the anticlockwise rotation of the upper bracket 5 is transmitted to the shield member 23 and the shield member 23 is brought into rotation against the aforementioned frictional force. Thus, as shown in Fig. 4, the shield member 23 is released from the shoulder 22 and the ratchet 6 becomes free to engage the pawl 8. At this time, since the anticlockwise rotation of the shield member 23 begins after the rotation of the upper bracket 5 through a fixed angle from position C, the ratchet 6 re-engages the pawl 8 at a fixed position D of the seat-back 4, which is intermediate position A and B as shown in Fig. 1. Thus, following the returning movement of the seat-back 4 after its forward inclination, the reclining angle of the seat-back 4 is always a suitable one for a passenger to sit on the seat.

It should be noted that it is the position of the projection 26 that returns the seat-back 4 to a desired - 6 reclining angle after its forward inclination. In other words, the position of the projection 26 serves to set the position at which the returning movement of the seat-back 4 is terminated.

In the present invention, owing to the elastic member 24, the geared portion 8a of the pawl 8 and the geared portion 6a of the ratchet 6 hardly wear out, thereby enabling continued smooth engagement therebetween.

Claims

CLAIMS:

1. A reclining seat device comprising:

a lower bracket; an upper bracket rotatably connected to the lower bracket by a pin; ratchet secured to the upper bracket; pawl connected td the lower bracket and ' 'biased towards engagement with the ratchet to prevent rotation of the upper bracket; a handle operable to engage or disengage the ratchet and pawl; means for preventing engagement of the ratchet and pawl when the upper bracket is in a forwardly inclined position; and means for causing re-engagement of the ratchet and pawl when the upper bracket is rotated back through a fixed angle from the forwardly inclined position.

2. A reclining seat device according to claim 1, wherein the means for preventing engagement comprises:

a shield member mounted to be movable into an interfering position between the pawl and the ratchet so as to prevent engagement between the pawl and the ratchet; and first projecting means mounted on the upper bracket for causing the shield member to move into its interfering position when the upper bracket is rotated to its forwardly inclined position.

3. A reclining seat device according to claim 2 wherein the means for causing re-engagement comprises second projecting means mounted on the upper bracket for causing the shield member to move out of its interfering position when the upper bracket is rotated back through the fixed angle, thereby allowing the pawl to be biased into engagement with the ratchet.

L 8

4. A reclining seat device according to claim 2 or claim 3 wherein the shield member is rotatably mounted on the pin connecting the upper and lower brackets.

5. A reclining seat sevice according to any preceding claim wherein the upper bracket is biased by a spring towards its forwardly inclined position.

6. A reclining seat device substantially as herein described with reference to the drawings.

01 Published 1991 at 7bePatentOlllce- State 130use. 66/71 Bigh liolborn, L4ondonWCIR47?. Further copies maybe obtained from Sales Branch. Unit 6, Nine Mile Point. Cwmrelinfacb. Cross Keys, Newport. NP1 7HZ- Printed by Multiplex techniques ltd. st Mary Cray. Kent.