JPH0461649B2 - - 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. 1 to 3, a lower bracket i fixed to a seat part and an upper bracket j fixed to a backrest part are fixed by an axis k, and the lower bracket i A latch a is fixed to one of the upper brackets j, and a latch c, which engages with the latch a, is fixed to the other by an axis e, and the outer peripheral edge of the latch a is centered on the axis k. A reclining device for a vehicle seat is known (Utility Model Publication No. 55-54367 (see publication).

In addition, in the conventionally known Utility Model Publication No. 55-54365,
A lower bracket fixed to the seat part and an upper bracket fixed to the backrest are fixed by a shaft, a latch is fixed to the lower bracket by the shaft, a latch is fixed to the upper bracket, and the latch is fixed to the upper bracket. The outer peripheral edge is an ellipse, and a part of the elliptical outer peripheral edge is cut out to form a rectangular recess having a notched edge on one side, and the tip edge of the pawl of the ratchet that engages with the rectangular recess is rectangular over the entire width. This document describes a reclining device for a vehicle seat that is formed into an arcuate surface that can be brought into close contact with the groove bottom of a recess.

(Problems to be Solved by the Invention) Among the above-mentioned publications, the former discloses that the inner edge f of the ratchet c has a small radius r, and the outer edge g has a large radius R.
Since the outer edge g moves more because of the difference in radius, the outer edge g moves more. Therefore, 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 the latch a is rotated counterclockwise and the claw d is engaged with the recess b, the tip edge m of the claw d will be in the recess. It ran onto the corner n of b, causing poor engagement,
This causes the tooth flying phenomenon to occur.

FIG. 4 shows an improved version of the above-mentioned known example, in which the outer circumferential arc edge of the latch is made into a perfect circular arc centered on the axis k, and the tip edge m of the claw portion c corresponds to the outer circumferential arc edge of the perfect circle. It is formed on the circular arc surfaces that are in contact with each other. With this structure, even when the claw part c moves and the tip edge m faces the upper part of the recess part b, there is no gap h at the outer edge g, so the tooth skipping phenomenon can be prevented.

In addition, in the latter described in the above-mentioned publication, the outer peripheral edge of the latch is an ellipse, a part of the elliptical outer peripheral edge is cut out to form a rectangular recess with a notched edge on one side, and the latch is engaged with the rectangular recess. Since the tip edge of the claw of the ratchet is formed into an arcuate surface that can be brought into close contact with the groove bottom of the rectangular recess over the entire width, when the tip edge of the ratchet claw faces the upper part of the rectangular recess, the third A gap h is formed as shown in the figure.

Strictly speaking, however, there are still points that need to be improved in the improvement plan shown in Figure 4. That is, since the outer circumferential arc edges near the recess b are at the same height, there is a risk that the outer edge g will not hit the recess b but may pass through it.

(Object of the Invention) The present invention reliably prevents tooth skipping by ensuring that the tip of the pawl of the ratchet more reliably engages with the recess of the latch.

(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 the lower bracket 1 Fix the latch 4 to either one of the upper bracket 2 and the upper bracket 2, and attach the latch 4 to the other one.
A ratchet 6 that engages with the latch 4 is fixed 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. A U-shaped recess 3 having cut edges 15 and 16 on both sides is formed by cutting out a part of 12,
The tip edge 11 of the claw portion 5 of the latch 6 that engages with the recess 3 extends over the entire width of the toothless portion 1 of the latch 4.
2, and the toothless portion 12 on the shaft 7 side of the toothless portion 12 near the recess 3.
This is a reclining device for a vehicle seat in which a notch 14 for preventing tooth skipping is formed which becomes deeper as it approaches the recess 3.

(Example) An example of the present invention will be explained with reference to FIG.
1 is a lower bracket fixed to the seat, 2 is an upper bracket fixed to the backrest, and shaft 1
3, one of the lower bracket 1 and the upper bracket 2 is provided with a latch 4 having a recess 3 formed on its outer peripheral surface, and the other has a claw 5 that engages with the recess 3. The ratchet 6 is mounted on a shaft 7.

The outer peripheral edge of the latch 4 is formed of an arc-shaped toothless part 12 centered on the shaft 13, and the recessed part 3 having notch edges 15 and 16 on both sides formed by cutting out a part of the toothless part 12. do.

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 shaft 7, and an inner edge 9 along a large diameter radius R centered on the shaft 7. axis 7
and the outer edge 10 on the more remote side.

The tip edge 11 of the claw portion 5 is formed into an arcuate surface that follows the arc of the outer periphery of the latch 4 while in contact with the outer periphery of the latch 4 .

Therefore, the toothless portion 12 on the shaft 7 side adjacent to the recess 3 is cut gently to form a notch 14 so as to become deeper as it approaches the recess 3. Height of edge 15 (head position)
is configured to be lower than the notch edge 16.

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

As is well known, when the backrest is tilted forward, the pawl 5 of the latch 6 is in contact with the toothless portion 12 of the latch 4, but the tip edge 11 of the pawl 5 extends over the entire width of the latch. Since it is formed into an arc that closely fits the outer circumferential edge of the perfect circle of 4, even when the claw part 5 slides on the toothless part 12 and faces the concave part 3, it faces the concave part 3 immediately. 3.Easy and secure engagement. Further, a toothless portion 12 on the shaft 7 side of the toothless portion 12 near the recess 3 is formed with a tooth skip prevention notch 14 that becomes deeper as it approaches the recess 3. The part 5 slides on the toothless part 12 and the recessed part 3
When facing, the outer edge 10 of the claw portion 5 comes into contact with the notch edge 16 located at a higher position because it is slightly lower.
Engage more securely.

(Effect) Among the above-mentioned known publications, the former has the inner edge f of the ratchet c having a small radius r, and the outer edge g having a large radius R.
Since the outer edge g moves more because of the difference in radius, the outer edge g moves more. Therefore, 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 the latch a is rotated counterclockwise and the claw d is engaged with the recess b, the tip edge m of the claw d will be in the recess. It ran onto the corner n of b, causing poor engagement,
This causes the tooth flying phenomenon to occur.

In the latter method, the outer peripheral edge of the latch is an ellipse, a part of the elliptical outer peripheral edge is cut out to form a rectangular recess with a notched edge on one side, and the latch engages with the rectangular recess. The tip edge of the ratchet part is formed into an arcuate surface that can fit closely to the bottom of the groove of the L-shaped recess over the entire width, so when the tip edge of the ratchet part faces the top of the L-shaped recess, it will look like the one shown in Figure 3. A gap h is formed between.

However, in the present invention, the lower bracket 1 fixed to the seat part and the upper bracket 2 fixed to the backrest are fixed by a shaft 13, and the lower bracket 1 and the upper bracket 2 are fixed to either one of the lower bracket 1 and the upper bracket 2. The latch 4 is fixed, and a latch 6 that engages with the latch 4 is fixed on the other side 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 U-shaped recess 3 having notch edges 15 and 16 on both sides is formed by cutting out a part of the toothless part 12, and the tip edge 11 of the pawl 5 of the ratchet 6 engages with the recess 3. 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 the recessed portion 3
This is a reclining device for a vehicle seat, in which a notch 14 for preventing tooth skipping is formed in the toothless portion 12 on the side of the shaft 7 among the toothless portions 12 in the vicinity, the tooth skipping prevention notch 14 becoming deeper as it approaches the recess 3. Therefore, 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 1
A U-shaped recess 3 having notch edges 15 and 16 on both sides is formed by cutting out a part of the toothless part 12, and the ratchet 6 engages with the recess 3.
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, so that when the tip edge 11 faces the recess 3, it will look like the shape shown in FIG. Since there is no gap, tooth skipping can be prevented.

Further, in the toothless portion 12 on the shaft 7 side of the toothless portion 12 in the vicinity of the recess 3, a notch 1 for preventing tooth skipping that gradually becomes deeper as it approaches the recess 3 is provided.
4, when the claw part 5 slides on the toothless part 12 and faces the recess 3, it is slightly lowered by the tooth skip prevention notch 14, so the outer edge 10 of the claw part 5 is relatively The notch edge 16 located at a high position is brought into contact with the notch edge 16 for more secure engagement.

[Brief explanation of the drawing]

1 to 3 are diagrams of known examples, FIG. 4 is a reference diagram for explaining the present application, and FIG. 5 is a diagram of an embodiment of the present application. 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... Notch portion, 15, 16... Notch edge.

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 lower bracket 1 and upper bracket 2, and a latch 6 that engages with the latch 4 is fixed to the other by a shaft 7. The outer peripheral edge is an arc-shaped toothless portion 12 having the same radius centered on the shaft 13, and the toothless portion 12 has cut edges 15, 16 on both sides formed by cutting out a part of the toothless portion 12.
A U-shaped recess 3 is formed, and the tip edge 11 of the pawl 5 of the latch 6 that engages with the recess 3 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; The toothless portion 12 on the shaft 7 side of the toothless portion 12 near the recess 3 has a notch 1 for preventing tooth skipping that becomes deeper as it approaches the recess 3.
4. A vehicle seat reclining device formed by a vehicle seat.