JP3755526B2 - Seat reclining device - Google Patents

Description

  The present invention relates to a seat reclining device.

Conventionally, as this type of seat reclining device, a lower arm fixed to a seat cushion, an upper arm fixed to a seat back, and the lower arm and the upper arm are rotatable, and the upper arm is rotatably supported by the lower arm. It has a rotary shaft, a lock mechanism that is provided between the lower arm and the upper arm and has a slidable pole and ratchet, and a lock release mechanism that has a cam that is supported by the rotary shaft and moves the pole. . In this conventional device, the rotation of the upper arm with respect to the lower arm is restricted by maintaining the meshing of the pole and ratchet by joining the pole and the cam, and the pole is made by rotating the rotating shaft to release the joining of the cam and the pole. And the ratchet are released from meshing to allow the upper arm to rotate relative to the lower arm. (For example, see Patent Document 1).
JP 59-34221 A

  However, in the above-described conventional device, when a load is applied to rotate the upper arm while the rotation of the upper arm with respect to the lower arm is restricted by the engagement of the pole and the ratchet, the reaction force is applied from the upper arm to the rotating shaft. Will act. As a result, the rotation of the operation shaft becomes heavy due to the reaction force, and the operability may be impaired. Therefore, this invention makes it the technical subject to improve the operativity of a rotating shaft.

In order to solve the above-described problem, the first technical means taken in the present invention includes a lower arm fixed to a seat cushion, an upper arm fixed to a seat back, and rotation with respect to the lower arm and the upper arm. A rotary shaft that is freely and rotatably supported by the upper arm and the lower arm, and a slidable pole and ratchet that are provided between the lower arm and the upper arm and restrict the rotation of the upper arm with respect to the lower arm. In a seat reclining device having a lock mechanism having a lock release mechanism having a cam that allows the upper arm to rotate relative to the lower arm by sliding the pole supported by the rotation shaft,
At least one of the upper arm and the lower arm to receive a reaction force that is provided between the lower arm and the upper arm and is generated by the lock mechanism so as not to act on the rotating shaft due to the rotation restriction of the upper arm with respect to the lower arm. A concave portion having an inner peripheral contact surface with the rotation axis as a center is formed on one side, and either one of the other is provided with an outer peripheral contact surface that slides in contact with the inner peripheral contact surface. A load receiving mechanism is provided, a support member is fixed to either the upper arm or the lower arm, the other outer edge is sandwiched from the outside of the outer edge, and the upper arm is rotated with respect to the lower arm. It was to be movable.

  In addition to the first means, the technical second means taken in the present invention includes the outer peripheral abutment surface that is inserted into and engaged with the other of the upper arm or the lower arm. That is, the projection is half-cut.

  Further, a third technical means taken in the present invention is that, in addition to the first or second means, the locking mechanism is provided between the lower arm and the upper arm which are formed by half-cutting and disposed in the space. It is what has been done.

  According to the first aspect of the present invention, when a load is input to rotate the upper arm in a state where the rotation of the upper arm with respect to the lower arm is restricted, the reaction force is received by the load receiving mechanism and the rotating shaft. Does not act on. Therefore, the rotation operation of the operation shaft does not become heavy due to the reaction force, and as a result, the operability of the rotation shaft can be improved. In addition, the concave portion, which is a part that receives the load of the load receiving mechanism, is formed by half-cutting the upper arm or the lower arm, has a small number of parts, and can receive the load in a large area, so that high strength can be realized.

  Further, as in the invention described in claim 2, in addition to the structure of claim 1, if the load receiving mechanism is provided with a concave portion and a convex portion that are formed by half punching in both the upper arm and the lower arm, The effect is that the number of parts can be made inexpensively and high strength can be secured.

  Furthermore, according to the third aspect of the present invention, if the lock mechanism is provided between the lower arm and the upper arm and disposed in the space, it is isolated from dust from the outside without adding a special part such as a cover. The reliability of the operation of the lock mechanism can be ensured. In addition, since the offset between the load receiving mechanism and the lock mechanism can be reduced with this configuration, the lock mechanism with high strength can be obtained.

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

  As shown in FIGS. 1 and 2, the lower arm 1 fixed to the seat cushion (not shown) and the upper arm 2 fixed to the seat back (not shown) are formed through both arms 1 and 2. The rotary shaft 3 is supported rotatably, and the upper arm 2 is rotatable about the rotary shaft 3 with respect to the lower arm 1. The support portions 11 and 12 of the lower arm 1 and the upper arm 2 with respect to the rotating shaft 3 are half-cut in opposite directions, and a space A is formed between the lower arm 1 and the upper arm 2 by half-cutting. In this space A, a cam 41 constituting the lock release mechanism 4, a pole 51 constituting a lock mechanism 5, and a ratchet 52 are disposed. The cam 41 is fixed to the rotary shaft 3 so as to rotate integrally with the two-sided width shape, and the ratchet 52 is formed integrally with the upper arm 2 in a circular arc shape with the rotary shaft 3 as the center by using half-cutting of the upper arm 2. Further, the pawl 51 is slidably disposed between the cam 41 and the ratchet 52 while being guided by the lower arm 1 and the upper arm 2, and can be joined to the cam 41 and meshed with the ratchet 52. Further, the cam 41 and the pole 51 are formed with a foot 41a and a cam surface 51a that can be engaged in the rotation direction. The pawl 51 and the cam 41 are joined by a projection 41b formed on the cam 41 and the cam-shaped back surface 51b of the pawl 51. The pawl 51 and the ratchet 52 are engaged with each other. This is performed by the tooth portion 51 c and the tooth portion 52 a formed on the ratchet 52.

  The upper arm 2 is fixedly attached with a retainer 23 (support member) fixed by a pin 22 located outside the outer shape of the lower arm 1. The retainer 23 extends from the outside of the outer shape of the lower arm 1 toward the center of rotation, and supports the upper arm 2 so as to sandwich the outer edge of the lower arm 1. Further, a retainer 15 (support member) is positioned on the opposite side of the retainer 23 with respect to the rotation shaft 3 and is attached to the lower arm 1 with a pin 14. It arrange | positions so that the edge of upper arm 2 external shape may be covered. With this configuration, the upper arm 2 and the lower arm 1 are configured to maintain their positions in the direction of the rotation center axis. It should be noted that the retainer can be simplified in its configuration by setting either the shape and strength appropriately.

  In the configuration described above, the rotation of the upper arm 2 relative to the lower arm 1 is restricted by restricting the sliding of the pole 51 by the joining of the pole 51 and the cam 41 and maintaining the meshing of the pole 51 and the ratchet 52. In this state, when the rotary shaft 3 is rotated in the clockwise direction shown in FIG. 1, the cam 41 is also rotated in the clockwise direction in FIG. 1 along with the rotation of the rotary shaft 3 so that the joint between the cam 41 and the pole 51 is released. The part 41a and the cam surface 51a are engaged, and the pole 51 is slid in the upward direction of FIG.

  As a result, the engagement between the pole 51 and the ratchet 52 is released, and the upper arm 2 is allowed to rotate relative to the lower arm 1. In the state where the upper arm 2 is allowed to rotate with respect to the lower arm 1, if the rotary shaft 3 is rotated in the opposite direction to the above, the pole 51 and the cam 41 are joined and the pole 51 slides in the opposite direction. I'll let you.

  Accordingly, the ratchet 52 and the pole 51 are engaged with each other, and the rotation of the upper arm 2 with respect to the lower arm 1 is restricted.

  The above-described configuration is arranged on both sides of the seat cushion and the seat back, and an operation handle 31 is fixed to the outer end of the rotary shaft 3 (the right end in FIG. 2). The end of the rotating shaft 3 in the sheet inward direction (left end in FIG. 2) is connected by a connecting rod 32.

  The load receiving mechanism 6 that is a main part of the present invention will be described.

  As shown in FIGS. 1 and 2, the upper arm 2 is formed with a semi-recessed recess 61 that has an arc shape centered on the rotation shaft 3 and that is continuous with the space A at both ends. Further, the lower arm 1 is formed with an arcuate convex portion 62 centered on the rotary shaft 3 in the same direction as the concave portion 61. The concave portion 61 and the convex portion 62 are combined by inserting the convex portion 62 into the concave portion 61 so as to abut on the upper and lower surfaces shown in FIG.

  In this configuration, when a load is applied to the upper arm 2 so as to rotate the upper arm 2 while the rotation of the upper arm 2 with respect to the lower arm 1 is restricted, the load is received by the engagement of the pole 51 and the ratchet 52, The reaction force is received by the contact between the concave portion 61 and the convex portion 62 and transmitted to the lower arm 1. In this way, a load that rotates the upper arm 2 applied to the upper arm 2 in a state where the rotation of the upper arm 2 with respect to the lower arm 1 is restricted is transmitted to the lower arm 1 without passing through the rotating shaft 3. Therefore, the rotation operation of the rotating shaft 3 is always ensured in a good state, and the operability is not impaired.

  In this configuration, the position of engagement between the pawl 51 and the ratchet 52 and the position of the load receiving mechanism 6 that receives the reaction force of the engagement are both between the upper arm 2 and the lower arm 1, and are approximately the same in the axial direction of the rotating shaft 3. They are in the same position. That is, even when the offset of the load support portion of the load receiving mechanism 6 is small with respect to the position where the pawl 51 and the ratchet 52 are engaged and a large load is applied to the reclining device, the pawl 51 and the ratchet 52 are disengaged. As a result, the occurrence of a moment acting as described above is reduced, and a high-strength locking performance is obtained.

  In order to avoid a load input to the rotating shaft 3, a bush 63 is disposed between the lower arm 1 and the rotating shaft 3 so as to be fixed to the lower arm 1, and between the upper arm 2 and the rotating shaft 3. A clearance 64 is formed in the case. The bush 63 is disposed between the upper arm 2 and the lower arm 1, and is a locking member to the lower arm 1 side of the spiral spring 9 that urges the lower arm 1 to rotate in the counterclockwise direction in FIG. It is also used as. The other end of the spiral spring 9 is locked to a projecting piece 23 a formed by cutting and raising the retainer 23.

1 is a plan view showing a first embodiment of a seat reclining device according to the present invention. It is the BB sectional view taken on the line of FIG.

Explanation of symbols

1 Lower Arm 2 Upper Arm 3 Rotating Shaft 4 Lock Release Mechanism 5 Lock Mechanism 15 Support Member (Retainer)
23 Support member (Retainer)
41 Cam 51 Pole 52 Ratchet 61 Recess (engagement part)
61a Inner peripheral contact surface 62 Convex part (engagement part)
62a Outer peripheral contact surface 6 Load receiving mechanism

Claims (3)

A lower arm fixed to the seat cushion,
An upper arm fixed to the seat back;
A rotating shaft that is rotatable with respect to the lower arm and the upper arm and is rotatably supported by the upper arm and the lower arm;
A lock mechanism having a slidable pole and a ratchet provided between the lower arm and the upper arm to restrict the rotation of the upper arm with respect to the lower arm;
In a seat reclining device having a lock release mechanism having a cam that is supported by the rotating shaft and allows the pole to slide and allow the upper arm to rotate with respect to the lower arm,
At least one of the upper arm and the lower arm to receive a reaction force that is provided between the lower arm and the upper arm and is generated by the lock mechanism so as not to act on the rotating shaft due to the rotation restriction of the upper arm with respect to the lower arm. A concave portion having an inner peripheral contact surface with the rotation axis as a center is formed on one side, and either one of the other is provided with an outer peripheral contact surface that slides in contact with the inner peripheral contact surface. A load receiving mechanism is provided, a support member is fixed to either the upper arm or the lower arm, the other outer edge is sandwiched from the outside of the outer edge, and the upper arm is rotated with respect to the lower arm. A seat reclining device that can move freely. 2. The seat reclining device according to claim 1, wherein a convex portion having the outer peripheral abutting surface that is inserted into and engaged with the concave portion is formed in a half-cut manner on either the upper arm or the lower arm. 3. The seat reclining device according to claim 1, wherein the lock mechanism is provided between the lower arm and the upper arm that are half-cut and disposed in a space.

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