JP2008301977A - Reclining device of seat - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reclining device of a seat capable of surely returning a seat back in a backward reclined state to its original state and suppressing a speed returning to a forward tilting position in the reclining device of the seat, which pivots an upper arm fixed to the seat back to a lower arm fixed to a seat cushion so as to be turned within a prescribed angle, and turnably energizes the upper arm in the forward tilting direction by a forward energizing spring. <P>SOLUTION: Besides the forward energizing spring, this reclining device is provided with a second energizing spring which applies no turning energizing force to the upper arm when the upper arm is positioned at a specific intermediate position of the full turning range of the upper arm, and applies resistance to each turning direction, in either cases where the upper arm is turned forward or rearward from the specific intermediate position. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a seat reclining device that urges a seat back to rotate forward with respect to a seat cushion.

For example, the front seat of a passenger car is attached to the lower arm fixed to the seat cushion so that the upper arm fixed to the seat back is pivotably pivoted within a certain angle range, and the upper arm is turned forward and biased forward. A spring is provided.
Japanese Utility Model Publication No. 6-70642

  The spring force of the front urging spring is set so that the seat back reliably returns to the forward direction when the reclining lock is released in a state where the seat back is tilted back to the maximum. However, if the spring force is simply set strong, at the moment when the reclining lock is released, the seat back returns to the forward direction at a high speed, and for example, there is a possibility that an object placed on the seat cushion is damaged by the seat back. On the other hand, if the spring force of the front urging spring is set to be weak in order to suppress the seatback return speed, there is a problem in that the seatback does not return or the return speed is slow.

  In general, the seat back is provided with a detachable headrest, and the weight of the entire seat back is different between the state in which the headrest is attached and the state in which the headrest is removed, which makes it difficult to set the spring force of the front biasing spring. ing. If the spring force of the front urging spring is set to a preferred strength with the headrest attached, the forward return speed will be increased in the removed state. On the contrary, there is a possibility that it does not return in a worn state with a preferred strength in the detached state.

  An object of the present invention is to provide a seat reclining device that can reliably return the seatback in the rearward state based on the above awareness of the problem and that can suppress the return speed to the forward position. .

  The present invention relates to a seat in which an upper arm fixed to a seat back is pivotally attached to a lower arm fixed to a seat cushion so as to be rotatable within a certain angle range, and the upper arm is urged to rotate forward by a forward urging spring. In the reclining device, the upper arm rotates forward and backward from the specific intermediate position without applying a rotational biasing force to the upper arm at a specific intermediate position in the entire rotation range of the upper arm, apart from the front biasing spring. In any case, a second urging spring is provided to provide resistance in each rotation direction.

  Specifically, for example, the second urging spring can be constituted by a tension coil spring stretched between the lower arm and the upper arm so as to be shortest at the specific intermediate position.

  In another aspect, the second urging spring is constituted by a torsion coil spring having a pair of hooks at both ends disposed at the relative rotation center of the lower arm and the upper arm, and the lower arm and the upper arm respectively have the specific intermediate position. A fixed protrusion and a rotating protrusion that engage with the pair of hooks may be formed.

  In the present invention, apart from the front biasing spring that biases the upper arm in the forward direction, the upper arm does not apply a rotational biasing force to the upper arm at the specific intermediate position of the entire rotational range of the upper arm. Since the second urging spring that provides resistance to the respective rotation directions is provided at any time when the vehicle is rotated forward and backward from the intermediate position, the second urging spring is used to seat the seat back at the rearward end. A forward biasing force is added. For this reason, the seat back can be reliably rotated in the forward direction. On the other hand, when the seatback is moved forward from the specific neutral position, the second urging spring acts as a brake in the forward movement direction, so that the forward movement speed can be suppressed.

  As shown in FIG. 1, a seat 10 in the front seat of a passenger car has a lower arm 12 fixed to a seat cushion 11 and an upper arm 14 fixed to a seat back 13, and the lower arm 12 and the upper arm 14 are pivoted. The shaft 15 is pivotally attached. FIG. 3 shows an example of the entire rotation range of the seat back 13 (upper arm 14) relative to the seat cushion 11 (lower arm 12), and the seat back 13 can be rotated between a forward-turning position and a backward-turning position. It is. As long as the lower arm 12 and the upper arm 14 are members fixed to the seat cushion 11 and the seat back 13, respectively, the form is not ask | required.

  A spiral spring (forward urging spring) 16 is mounted around the rotation center axis 15. The inner end portion of the spiral spring 16 is mounted on the lower arm 12 while restricting the rotation, and the outer end portion is hooked on a spring receiving pin 17 erected on the upper arm 14. The spiral spring 16 urges the seat back 13 to rotate forward in the entire rotation range of the seat back 13. This forward biasing force is strongest when the seat back 13 is rotated to the rearward position.

  As shown in FIG. 2, a known reclining lock 20 that locks the seat back 13 in an arbitrary position against the force of the spiral spring 16 is provided around the rotation center axis 15. In the illustrated example, the upper arm 14 is formed with a lock tooth 14a positioned on an arc around the rotation center shaft 15, and a lock lever 22 pivotally attached to the lower arm 12 by a shaft 21 is engaged with the lock tooth 14a. Teeth are provided. The lock lever 22 is engaged with an operation lever 23 supported on the rotation center shaft 15 so as to be rotatable. When the operation lever 23 is pulled up against the force of the tension spring 24, the lock teeth of the upper arm 14 are locked. 14a and the lock teeth of the lock lever 22 are disengaged, and the upper arm 14 (seat back 13) can be freely rotated. On the other hand, when the operating force to the operation lever 23 is released, the lock teeth 14a of the upper arm 14 and the lock teeth of the lock lever 22 are engaged, and the rotation of the upper arm 14 (seat back 13) is locked. Various structures are known for the reclining lock 20 having such a function, and the present invention is not limited to the structure of the reclining lock 20, so only the above description will be given.

  In the present embodiment, the second urging spring 30 is further provided in the reclining device in which the seat back 13 (upper arm 14) is urged to rotate forward by the spiral spring 16 as described above. As shown in FIGS. 2 and 4, the second urging spring 30 includes a tension coil spring 30 </ b> C stretched between a spring receiving pin 31 standing on the lower arm 12 and a spring receiving pin 32 standing on the upper arm 14. ing. In FIG. 4, the inner end of the spiral spring 16 is latched by a latching projection 12 a formed on the lower arm 12, and the outer end is latched by a latching projection 14 b formed on the upper arm 14.

  As shown in FIG. 4B, the tension coil spring 30C is positioned at a specific intermediate position in the entire rotation range of the seat back 13 so as not to give a rotation biasing force to the upper arm 14, as shown in FIG. . Then, when the upper arm 14 is rotated in the forward direction from the state of FIG. 4B, as shown in FIG. 4A, the upper arm 14 expands to give resistance to the rotation. Further, when the upper arm 14 is rotated backward from the state of FIG. 4B, as shown in FIG. 4C, it is similarly expanded to give resistance to the rotation.

  In other words, according to the present embodiment, at the rearward end of the seat back 13 (upper arm 14), in addition to the forward biasing force by the spiral spring 16, a forward biasing force is applied by the tension coil spring 30C. Is done. For this reason, the seat back can be reliably rotated in the forward direction. The urging force in the forward direction by the tension coil spring 30 </ b> C acts only up to the specific neutral position, and when the seat back 13 moves further in the forward direction from the specific neutral position, the tension coil spring 30 </ b> C moves to the upper arm 14. Since it acts as a brake, it is possible to suppress the forward speed of the upper arm 14 that is urged to rotate forward by the spiral spring 16. Of course, the strength of the tension coil spring 30 </ b> C is set so as not to prevent the spiral spring 16 from moving the upper arm 14 to the forward tilt position.

The “specific neutral position” does not mean the correct middle between the front end and the rear end. Considering the strength of the forward biasing spring 16, either the forward fall end or the rear fall end at the rear fall end depends on whether the return force at the rear fall end is important or the speed control at the front fall end is important. The “specific neutral position” can be set by approaching to.

  5 and 6 show another embodiment of the seat reclining device according to the present invention. This embodiment is an embodiment in which a torsion coil spring 30T whose single shape is shown in FIG. 6 is used as the second urging spring. The torsion coil spring 30T has hook portions 30f at both ends of the coil portion 30c. In the free state of FIG. 6, the pair of hook portions 30f are moved closer to each other and further moved away from each other, thereby moving the coil portion. Torsion energy is stored in 30c.

  As shown in FIG. 5, the lower arm 12 is formed with a fixed protrusion 12f that engages with a pair of hook portions 30f in a state where torsion energy is stored, and the upper arm 14 is positioned around the fixed protrusion 12f. A rotation protrusion 14m that moves around the movement center shaft 15 is formed. In FIG. 5, the spiral spring (front biasing spring) is not drawn, but is present as in the first embodiment.

As shown in FIG. 5B, the pair of hook portions 30f of the torsion coil spring 30T abuts both the fixed protrusion 12f and the rotation protrusion 14m at a specific intermediate position in the entire rotation range of the seat back 13. Therefore, the rotational biasing force does not act on the upper arm 14. Then, even if the upper arm 14 is rotated forward from the state of FIG. 5B (FIG. 5A) or rotated backward (FIG. 5C), the upper arm 14 The pair of hook portions 30f are separated by the rotation protrusion 14m, and torsion energy is stored in the coil portion 30c (resistance is given to the rotation). Therefore, the same operation as that of the first embodiment can be obtained.

It is an appearance perspective view of a sheet which has a reclining device to which the present invention is applied. It is a disassembled perspective view of the principal part which shows one Embodiment of the reclining apparatus of the sheet | seat by this invention. It is a side view which shows an example of the full rotation angle range of a seat back. (A), (b), (c) is a side view which shows the different operation | movement condition of the reclining apparatus of the sheet | seat by this invention. (A), (b), (c) is a side view corresponding to (a), (b), (c) of FIG. 4 which shows another embodiment of the reclining apparatus of the sheet | seat by this invention. It is a perspective view of the torsion coil spring single-piece | unit used for embodiment of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Seat 11 Seat cushion 12 Lower arm 12f Fixing protrusion 13 Seat back 14 Upper arm 14m Turning protrusion 15 Turning center axis 16 Spiral spring (front biasing spring)
20 Reclining lock 22 Lock lever 23 Operation lever 24 Tension spring 30C Tension coil spring (second biasing spring)
30T Torsion coil spring (second biasing spring)
30c Coil part 30f Hook part

Claims (3)

In a seat reclining device in which an upper arm fixed to a seat back is pivotally attached to a lower arm fixed to a seat cushion so as to be rotatable within a predetermined angle range, and the upper arm is urged to rotate forward by a forward urging spring. ,
Separately from the front biasing spring, at a specific intermediate position of the entire rotation range of the upper arm, no rotation biasing force is applied to the upper arm, and either when the upper arm rotates forward or backward from the specific intermediate position. The seat reclining device is characterized in that a second urging spring is provided to provide resistance in each rotation direction. 2. The seat reclining device according to claim 1, wherein the second biasing spring is a tension coil spring stretched between the lower arm and the upper arm so as to be shortest at the specific intermediate position. 2. The seat reclining device according to claim 1, wherein the second urging spring is a torsion coil spring having a pair of hooks at both ends disposed at a relative rotation center between the lower arm and the upper arm. A seat reclining device in which a fixed protrusion and a rotating protrusion are formed to engage with the pair of hooks at the specific intermediate position, respectively.

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