JPH0461650B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a reclining device for a vehicle seat.

(Prior Art) Conventionally, as shown in FIGS. 3 and 4, a latch a is provided with a recess b in either a lower bracket fixed to the seat or an upper bracket fixed to the backrest. It is known that a ratchet c having a claw portion d on either side is fixed by a shaft e (Japanese Utility Model Publication No. 54367/1983).

Further, a gear having saw teeth is fixed to either one of the lower bracket fixed to the seat part and the upper bracket fixed to the backrest part, and a ratchet having a pawl part is fixed to one of the other by a shaft. It is also known that the distal end edge of the claw portion is formed into an arcuate surface that closely contacts the saw teeth (Japanese Utility Model Publication No. 54365/1983).

(Problem to be solved by the invention) In the former case, the inner edge f of the ratchet c has a radius r
Since the outer edge g moves with a radius R, the outer edge g moves more due to the difference in radius. Therefore, as shown in Fig. 4, when the pawl d of the latch c engages with or disengages from the recess b of the latch a, a large gap h is formed between the outer edge g and the latch a, and the latch is lifted up. Becomes in a state of ivy. In this way, between h
If this is formed, for example, when the latch a is rotated in the direction of the arrow i, the tip edge k of the pawl d tends to be misaligned and rides on the corner n of the recess b, resulting in poor engagement, resulting in a tooth skipping phenomenon. This causes the occurrence of

In addition, in the latter case, the tip edge of the claw part is formed into an arcuate surface, but the arcuate edge is not an arcuate edge that matches the outer circumferential arcuate edge of the latch, but an arcuate edge that fits the bottom edge of the sawtooth. The gap n shown in Figure 4 still remains.

(Means for Solving the Problems) Therefore, the present invention provides a structure in which the lower bracket 1 fixed to the seat portion and the upper bracket 2 fixed to the backrest portion are fixed by a shaft 13, and both the brackets 1 are fixed to each other. , 2, a latch 4 is fixed to one of them, and a latch 6 is attached to the other by a shaft 7,
The outer peripheral edge of the latch 4 is an arc-shaped toothless portion 12 having the same radius centered on the shaft 13, and the toothless portion 12
A part of it is cut out and the cut edges 14 and 15 on both sides are cut out.
and a recess 3 having a bottom edge 16, and the ratchet 6 is formed with a pawl 5 that engages with the recess 3, and the inner edge 9 and the outer edge 10 of the pawl 5 are respectively centered on the axis 7. The claw portion 5 is formed into an arcuate surface.
The tip edge 11 of the latch 4 is formed into an arcuate surface that can be brought into close contact with the toothless portion 12 of the latch 4 over the entire width, and is used as a reclining device for a vehicle seat.

(Embodiment) To explain one embodiment of the present invention with reference to the drawings, 1 is a lower bracket fixed to the seat, 2 is an upper bracket fixed to the backrest, and both brackets 1 and 2 are connected to a shaft 13. One of the brackets 1 and 2 is provided with a latch 4 having a recess 3 formed on its outer peripheral surface, and the other is provided with a latch 6 having a claw 5 that engages with the recess 3. 7.

The outer periphery of the latch 4 is an arc-shaped toothless portion 12 having the same radius centered on the shaft 13, and the toothless portion 12 has notched edges 1 on both sides of the toothless portion 12.
4 and 15 and a bottom edge 16, a U-shaped recess 3 is formed.

The ratchet 6 is formed of an arm portion 8 extending radially from the shaft 7, and a claw portion 5 bent from the tip of the arm portion 8 in the direction of the latch 4.

The shape of the claw portion 5 includes an inner edge 9 on the side closer to the shaft 7 along a small diameter radius r centered on the axis of the shaft 7, and an inner edge 9 along a large diameter radius R centered on the axis 7. ivy axis 7
and the outer edge 10 on the far side.

The tip edge 11 of the claw portion 5 is formed into an arcuate surface that follows the arc of the toothless portion 12 of the latch 4. 17
is the intersection of the arcuate toothless portion 12 and the notch edge 15 of the recess 3.

(Function) Because of the above configuration, the present invention exhibits the following functions.

When the backrest is tilted forward, the tip edge 11 of the claw portion 5 of the latch 6 touches the arc-shaped toothless portion 1 of the latch 4.
2 (Fig. 1), and at this time, since the tip edge 11 of the claw part 5 is formed into an arc parallel to the toothless part 12, it is in close contact with the toothless part 12 over the entire width. .

When the backrest is pulled up in this state, the tip edge 11 of the claw 5 slides on the toothless portion 12 and faces the recess 3. In this case, the tip edge 11 slides on the toothless portion 12. 12, the inner edge 9 and the outer edge 10 both face the entrance of the recess 3 in the same state, and the outer edge 10 in particular faces the gap h as in the known example.
does not form.

Therefore, unlike in FIG. 4, the leading edge 11 does not ride on the corner 16 of the recess 3, and engages easily and reliably.

In addition, the shape of the claw portion 5 is changed to the inner edge 9 on the side closer to the shaft 7 along the small radius r centered on the axis of the shaft 7.
and the outer edge 10 on the side far from the shaft 7 along the large radius R centered on the axis of the shaft 7,
Since the inner edge 9 and the outer edge 10 only move on the same trajectory after the tip edge 11 engages with the entrance of the recess 3 until it enters the deepest part, they engage smoothly (the inner edge 9 If the outer edge 10 is formed in a straight line, the relative positions of the latch 4 and the latch 8 will be forcibly shifted when the claw portion 5 engages with the recess 3, and smooth engagement cannot be expected). Also, inner edge 9
Since the outer edge 10 is shaped like an arc, the force applied from the latch 4 to the latch 8 is due to the axis 7 of the latch 8.
Since the force acting only on the center of the ratchet 8 does not become a force that rotates the ratchet 8, there is no risk that the claw 5 will come off the recess 3.

(Effects) Conventionally, as shown in FIGS. 3 and 4, a latch a having a concave portion b in either one of a lower bracket fixed to the seat portion and an upper bracket fixed to the backrest has been used. It is known that a ratchet c having a claw portion d on the other side is fixed by an axis e, and one of the lower bracket fixed to the seat portion and the upper bracket fixed to the backrest portion is provided with saw teeth. It is known that a ratchet having a tooth is fixed thereto, a ratchet having a pawl portion on the other side is fixed by a shaft, and the distal end edge of the pawl portion is formed into an arcuate surface that closely contacts the saw tooth.

However, in the former case, the inner edge f of the ratchet c
has a radius r, and the outer edge g moves with a radius R, so the outer edge g moves more due to the difference in radius. Therefore, as shown in FIG. 4, when the pawl d of the latch c engages with or disengages from the recess b of the latch a, there is a large gap h between the outer edge g and the latch a.
is formed and becomes elevated. When the gap h is formed in this way, for example, when rotating the latch a in the direction of the arrow i, the tip edge k of the claw portion d
is likely to be misaligned and ride on the corner n of the recess b, resulting in poor engagement and causing a tooth-skipping phenomenon. In addition, in the latter case, the tip edge of the claw part is formed into an arcuate surface, but the arcuate edge is not an arcuate edge that matches the outer circumferential arcuate edge of the latch, but an arcuate edge that fits the bottom edge of the sawtooth. As shown in Figure 4, the gap n still remains.

However, in the present invention, the lower bracket 1 fixed to the seat portion and the upper bracket 2 fixed to the backrest are fixed by a shaft 13, and a latch 4 is attached to either one of the brackets 1, 2. A latch 6 is fixed to the other one by a shaft 7, and the outer peripheral edge of the latch 4 is an arc-shaped toothless portion 12 having the same radius centered on the shaft 13. Cut out the notch edges 14 on both sides,
15 and a bottom edge 16, the ratchet 6 is formed with a pawl 5 that engages with the recess 3, and the inner edge 9 and outer edge 10 of the pawl 5 are respectively centered on the axis 7. The tip edge 11 of the claw portion 5 is formed into an arcuate surface that can be brought into close contact with the toothless portion 12 of the latch 4 over the entire width of the reclining device for a vehicle seat. Just by slightly forming the tip edge 11 of the pawl portion 5 into an arcuate surface that can be brought into close contact with the toothless portion 12 of the latch 4 over the entire width, tooth skipping can be prevented, and implementation is possible without any cost. has the feature of being extremely easy.

[Brief explanation of drawings]

Figure 1 is an overall side view, Figure 2 is a side view of main parts,
3 and 4 are side views of known examples. Explanation of symbols, 1...Lower bracket, 2...
Upper bracket, 3... recess, 4... latch, 5... pawl, 6... ratchet, 7... shaft,
8...Arm part, 9...Inner edge, 10...Outer edge, 1
1...Tip edge, 12...Toothless part, 13...Shaft, 1
4, 15...notch edge, 16...bottom edge, 17...intersection.

Claims (1)

[Claims] 1 The lower bracket 1 fixed to the seat and the upper bracket 2 fixed to the backrest are connected to the shaft 1.
A latch 4 is fixed to one of the brackets 1 and 2, and a latch 6 is pivotally attached to the other of the brackets 1 and 2 by a shaft 7, and the outer peripheral edge of the latch 4 is centered on the shaft 13. A circular arc-shaped toothless portion 12 having the same radius is formed, and a part of the toothless portion 12 is cut out to form a recess 3 having notch edges 14 and 15 on both sides and a bottom edge 16. 3, the inner edge 9 and the outer edge 10 of the claw part 5 are each formed into an arcuate surface centered on the shaft 7, and the tip edge 11 of the claw part 5 extends over the entire width. A reclining device for a vehicle seat formed into an arcuate surface that can be brought into close contact with the toothless portion 12 of the latch 4.