JPH08214978A - Reclining device - Google Patents

Abstract

PURPOSE: To provide a reclining device capable of securing the engaging strength between a ratchet and a pole and finely adjusting the slant angle of a seat back when the size of a reclining device is to be reduced. CONSTITUTION: Poles 13 and 14 are positioned in the inside of the diameter of a ratchet 11d and the tooth height is not changed and the number of teeth is reduced when the diameter of the ratchet 11 is reduced. In this case, the pitch becomes larger at the tooth part of the ratchet 11d, and the poles 13 and 14 are respectively so mounted as to engage mutually selectively with the ratchet 11d. By selective engagement of each of poles 13 and 14 with the ratchet 11d, the large pitch of the tooth part of the ratchet 11d is compensated to enable fine adjustment of the slant angle of a seat back. Since the tooth height is not changed in this case, the engaging strength between the ratchet 11d and the poles 13 and 14 are sufficiently secured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reclining device in which a lower portion of a seat back is rotatably mounted in a rear portion of a seat cushion so that a tilt angle of the seat back in the front and rear direction can be adjusted.

[0002]

2. Description of the Related Art A reclining device is generally a ratchet fixedly provided on an upper arm that is assembled to a seat back, and a pole that is swingably provided on a lower arm that is assembled to a seat cushion and that moves forward and backward with respect to the ratchet. It has a release lever that is rotatably attached to the lower arm and that swings the pole.The seat back is fixed to the seat cushion by locking the upper arm to the lower arm by engaging the pole with a part of the teeth of the ratchet. The seat back to the seat cushion by releasing the lock of the upper arm from the lower arm by swinging the pole by the release lever turning operation to move the pole away from the ratchet teeth. The seat back in the front-back direction. And it makes it possible to adjust the inclination angle of the longitudinal direction of the seat back as rotatably.

In the reclining device, since the pole is located on the outer peripheral side of the arcuate tooth portion of the ratchet, the diameter of the arcuate tooth portion of the ratchet is reduced in order to miniaturize the reclining device. There is a need. In this case, if the means for reducing the size of the module by making the diameter of the pitch circle small by making the number of teeth of the ratchet invariant is adopted, the tooth length becomes small and the meshing strength of the meshing part of the ratchet and the pole decreases. There is. Further, in place of such means, if a means for reducing the number of teeth by making the tooth length invariable is adopted in order to prevent a decrease in the meshing strength between the ratchet and the pole, the pitch, which is the interval between adjacent teeth, becomes large, and in the reclining device. The adjustment interval of the tilt angle becomes coarse, and it becomes impossible to finely adjust the tilt angle.

On the other hand, unlike the reclining device of this type, Japanese Patent Publication No. 63-65327 discloses a reclining device in which a pole is arranged inside the diameter of a ring-shaped ratchet having internal teeth. . The reclining device is composed of a pair of ring-shaped ratchets concentrically provided on both the upper arm and the lower arm, and a plurality of base end portions that are sandwiched between these arms and that have their base end portions facing each other on the inner diameter side of both ratchets. Poles, cam means arranged at the base ends of these poles to move each pole forward and backward with respect to both ratchets, and the cam means are rotated to cause each pole to mesh with and separate from both ratchets. It is configured with an operating lever. Therefore, the reclining device can be downsized as compared with the former general reclining device because each pole is located inside the diameter of each ratchet.

[0005]

However, even in the latter reclining device described above, when the diameters of both ratchets are reduced to further reduce the size, the same problem as in the former reclining device, that is, The tooth height becomes smaller and the meshing strength between the ratchet and pole decreases, or the pitch, which is the spacing between adjacent teeth, becomes larger, and the adjustment angle of the tilt angle in the reclining device becomes coarse, making it impossible to finely adjust the tilt angle. The problem of becoming Therefore, it is an object of the present invention to solve these problems.

[0006]

SUMMARY OF THE INVENTION The present invention is a reclining device in which a lower portion of a seat back is rotatably assembled in a rear portion of a seat cushion so that a tilt angle of the seat back in the longitudinal direction can be adjusted. And a ring-shaped ratchet having internal teeth provided on the upper arm that is assembled to the seat back, and a lower arm that is assembled to the seat cushion and that is concentrically fitted to the ratchet on the upper arm. And a support portion that rotatably supports the upper arm in the front-rear direction, and a plurality of poles that are sandwiched between the two arms and that are capable of advancing and retracting with respect to the inner teeth of the ratchet inside the ratchet, An operating shaft that penetrates both arms concentrically with respect to the ratchet and is inserted between the base end portions of the respective poles that face each other; The pawl is provided between the outer periphery of the shaft and the base end of each pawl and is biased by a spring to hold each pawl in a forward movement state so as to mesh with the internal teeth of the ratchet and to operate by the rotational movement of the operating shaft. Cam means for retracting each pole to separate it from the inner teeth of the ratchet,
An operating lever connected to the operating shaft to rotate the operating shaft by a rotating operation is provided, and the respective pawls are set to selectively mesh with the ratchet.

In the reclining device, however, two poles are adopted as the poles, and these two poles are arranged on the diameter line inside the ratchet while the tooth pitches are displaced in the circumferential direction from each other. In addition, it is preferable that the operation shaft is configured to be movable by a predetermined amount along the diameter line.

[0008]

In the reclining device constructed as described above, when the operating lever is not operated, one of the pawls is engaged with a part of the tooth portion of the ratchet and the upper arm is locked to the lower arm. The seat back is fixed to the seat cushion, and the seat back stands up while maintaining a predetermined inclination angle in the front-rear direction.
Further, in the reclining device in this state, when the operation lever is operated to rotate, the operation shaft rotates and each pole retracts from the ratchet, and the pole meshed with a part of the ratchet teeth is separated from the ratchet. Unlock the upper arm from the lower arm and unlock the seat back from the seat cushion. As a result, the seat back can be rotated in the front-rear direction, and the seat back can be adjusted to an arbitrary inclination angle. If the turning operation of the operating lever is released after adjusting the tilt angle, each pole moves forward with respect to the tooth portion of the ratchet, and one of the poles meshes with the other portion of the tooth portion of the ratchet. Lock the upper arm to the lower arm and secure the seat back to the seat cushion. As a result, the seat back is held at the adjusted tilt angle.

By the way, in the reclining device, since each pole is arranged on the inner side of the ratchet, the pole is arranged on the outer peripheral side of the tooth portion of the ratchet as compared with the former reclining device shown at the beginning. Of course, compared to the latter reclining device shown at the beginning of the type in which each pole is arranged radially inside the tooth portion of the ring-shaped ratchet,
Miniaturization is possible for the following reasons.

That is, in the reclining device according to the present invention, when the diameter of the ratchet is reduced to reduce the size of the ratchet, a means for reducing the number of teeth while keeping the tooth length unchanged is adopted. In this case, in the tooth portion of the ratchet, the pitch, which is the interval between the adjacent teeth, becomes large, but since each of the pawls is set to selectively mesh with the ratchet, Despite the large pitch setting, the selective engagement of the poles with respect to the ratchet compensates for the large pitch of the teeth of the ratchet and allows a fine adjustment of the seat back tilt angle. In this case, since the tooth height is unchanged, the meshing strength between the ratchet and the pole is sufficiently secured.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIGS. 1 to 4 show a reclining device 10 according to an embodiment of the present invention. The reclining device 10 supports a lower end portion of a seat back 21 constituting a vehicle seat 20 shown in FIG. 7A at a rear portion of a seat cushion 22, and the reclining device 10A on the right side.
The seat back 21 is supported in cooperation with, or the seat back 21 is supported in cooperation with a mere hinge pin instead of the reclining device 10A on the right side. The reclining device 10 mainly includes an upper arm 11, a lower arm 12, a pair of pawls 13 and 14, an operating shaft 15, an operating lever 16, a large-diameter first torsion spring 17a, and a small-diameter second torsion spring 17b.

The upper arm 11 has an assembling portion 11a to be attached to the lower end of the seat back 21, and a large-diameter annular first recess 11b which bulges outward below the assembling portion 11a. A second annular recess 11c having a small diameter is provided. Ring-shaped internal teeth are formed on the outer peripheral edge of the first recess 11b, and the outer peripheral edge constitutes the ratchet 11d. Further, in the upper arm 11, the third recesses 11b and 11c are formed so as to be relatively formed.
A through hole 11f is formed at the center of the recess 11e,
Further, the tubular body 18 is fitted and fixed in the recess 11e.

The lower arm 12 has an assembly portion 12a which is assembled to the rear end of the seat cushion 22, and
A large-diameter semicircular first protrusion 12b1 that bulges inward above the assembling portion 12a, a small-diameter semicircular second protrusion 12c1 that follows the first protrusion 12b1, and a predetermined interval therebetween. It is provided with a large-diameter semicircular first protrusion 12b2 facing each other and a small-diameter semicircular second protrusion 12c2 following the first protrusion 12b2. Further, a through hole 12d is formed between the first protrusions 12b1 and 12b2. Both first protrusions 12b1, 12
b2 is formed in such a size that it fits into the first recess 11b of the upper arm 11 without any play, and the second protrusions 12c
1, 12c2 are formed in such a size that they fit into the second recess 11c of the upper arm 11 without any play, and the through hole 12
d has the same diameter as the through hole 11f of the upper arm 11 and is formed at a position facing each other.

Both poles 13 and 14 have the same shape, and both first protrusions 12b1 and 12b of the lower arm 12 are provided.
Arc-shaped tooth portions 13a and 14a are formed on the tip end side of the plate-shaped main body having a width dimension close to the interval between b2, and cam surfaces 13b and 14b are formed on the base end portion. The arcuate tooth portions 13a and 14a and the tooth portion of the ratchet 14d are formed to have the same specifications, and can mesh with each other. The operation shaft 15 includes a first connecting portion 15b having serrations on the inner end of the shaft body 15a, an elliptical second connecting portion 15c on the outer end side, and a pair of cam followers 15d on the outer periphery of the middle portion of the shaft body 15a. , 15e, and the outer diameter of the shaft body 15a is formed to be slightly smaller than the through holes 11f, 12d of both arms 11, 12.

The upper arm 11 has a first recess 11b and a second recess 11 with the operating shaft 15 penetrating through the through holes 11f and 12d of both arms 11 and 12 and the cylindrical body 18.
c is fitted on the first protrusions 12b1 and 12b2 and the second protrusions 12c1 and 12c2 of the lower arm 12 and is superimposed on the lower arm 12, and in this state, both poles 1
Reference numerals 3 and 14 denote both first protrusions 12b1 and 1 of the lower arm 12.
It is located slidably in the vertical direction between 2b2 and each cam surface 13
b and 14b are cam followers 15d and 1 of the operating shaft 15.
5e is fitted on each of the arcuate tooth portions 13a,
14a opposes the ratchet 14d so as to be capable of meshing.

In this state, the upper arm 12 is clamped by the pair of clamping pins 19a and 19b in a state of overlapping with the lower arm 12, and the second protrusion 12c of the lower arm 12 is clamped.
The lower arm 12 is rotatably supported in the front-rear direction by using the support members 1 and 12c2. Also, both poles 1
3 and 14 are vertically slidable between the first projections 12b1 and 12b2 of the lower arm 12 while being sandwiched by the arms 11 and 12, and the poles 1 and
The arcuate tooth portions 13a and 14a of 3 and 14 are displaced from each other by 1/2 pitch with respect to the tooth portion of the ratchet 11d.

Further, in the operation shaft 15, the base end portion of the operation lever 16 is fitted on the second connecting portion 15c of the operation shaft 15 to prevent the operation lever 15 from coming off, and a hooking groove 15f provided in the second connecting portion 15c. Each end of the second torsion spring 17b is hooked on the hooking groove 18a of the cylindrical body 18. As a result, the operating shaft 15 is urged in the counterclockwise direction in the drawing to engage the cam followers 15d and 15e with the cam surfaces 13b and 14b of the pawls 13 and 14, respectively, as shown in FIG. 13 and 14 are slid toward the ratchet 11d side to selectively mesh with the ratchet 11d. In the figure, the teeth 14a of the lower pole 14 mesh with the ratchet 11d, and the teeth 13a of the upper pole 13
The tooth tops of the above are in contact with the tooth tops of the tooth portions of the ratchet 11d.

The upper arm 11 is a seat back 2
The lower arm 12 is fixed to the left side of the lower end portion of the seat cushion 22, and the lower arm 12 is fixed to the left side of the rear end portion of the seat cushion 22, but the hooking groove 18b of the cylindrical body 18 and the holding pin 19b have the first torsion spring 17a. Each end is hooked, and the upper arm 11 is always biased counterclockwise in the drawing. As a result, the seat back 21 is always urged forward and the ratchet 1 of each pole 13, 14 is
It is fixed by selective meshing with 1d and is held at a predetermined inclination angle in the front-rear direction.

The reclining device 1 thus constructed
At 0, the operating shaft 15 is urged by the second torsion spring 17b so that the cam followers 15d, 15
e is engaged with the cam surfaces 13b and 14b of the pawls 13 and 14, respectively, and as shown in FIG. 5, one of the pawls 13 and 14 is engaged with the ratchet 11d. As a result, the upper arm 11 is locked to the lower arm 12 and holds the seat back 21 at a predetermined tilt angle.

In this state, when the operation lever 16 is rotated clockwise against the second torsion spring 17b, the operation shaft 15 rotates in the same direction, and as shown in FIG.
Attach each cam follower 15d, 15e to each pole 13, 14
The cam surfaces 13b and 14b are separated from the cam surfaces 13b and 14b, and are hooked on the hook portions 13c and 14c, respectively, and the pawls 13 and 14 are drawn radially inward to separate from the ratchet 11d. As a result, the lock of the upper arm 11 with respect to the lower arm 12 is released, the seat back 21 is released from being fixed to the seat cushion 22 and is rotatable in the front-rear direction, and the inclination angle in the front-rear direction can be adjusted. If the rotation operation of the operation lever 16 is released after the angle of the seat back 21 is adjusted, the operation shaft 15 is rotated and returned by the urging force of the second torsion spring 17b, and the action of the cam followers 15d and 15e causes both poles to move. 13, 1
The upper arm 11 is locked to the lower arm 12 by engaging one of the four with the ratchet 11d, and the seat back 21 is held at the adjusted inclination angle.

By the way, in the reclining device 10, the poles 13 and 14 are arranged radially inside the ratchet 11d, so that the reclining device of the type in which the pawls are arranged on the outer peripheral side of the tooth portion of the ratchet is compared. The size can be reduced, and even if compared with a reclining device of a type in which each pole is arranged inside the tooth portion of the ratchet, the size can be reduced for the following reason.

That is, the reclining device 10 employs a means for reducing the number of teeth by making the tooth length unchanged when the diameter of the ratchet 11d is reduced and the size is reduced. In this case, in the tooth portion of the ratchet 11d, the pitch, which is the distance between the adjacent teeth, becomes large, but the arc-shaped tooth portions 13a and 14a of the poles 13 and 14 are 1 / the pitch of the tooth portion of the ratchet 11d. 2 pitches are arranged, and each pole 13 with respect to the ratchet 11d,
14 are set to selectively mesh with each other. Therefore, although the tooth pitch of the tooth portions 13a, 14a of the ratchet 11d and the pawls 13, 14 is set to be large, the poles 13, 1 for the ratchet 11d are set.
The large meshing of the tooth portions of the ratchet 11d is compensated by the selective meshing of No. 4, and the fine inclination angle of the seat back 21 can be adjusted. In this case, since the tooth height is unchanged, the meshing strength between the ratchet 11d and the pawls 13 and 14 is sufficiently secured.

In the reclining device 10,
The specific specifications of the ratchet 11d and the teeth of the poles 13 and 14 are as follows. That is, the specifications of the teeth of the reclining device serving as the reference are the module 0.55, the pitch circle diameter 99, the number of teeth 180, and the pitch of 2 degrees, whereas the specifications of the teeth of the miniaturized reclining device 10 are smaller. The original is module 0.6, pitch circle diameter 54, number of teeth 90, pitch 4 degrees, each pole 1
The teeth of the arcuate tooth portions 13a and 14 of 3 and 14 are set to be offset from each other by 2 degrees. Thereby, in the reclining device 10, the tooth height is set to be the same as that of the standard reclining device, and the ratchet 11d and the poles 13,
Sufficient meshing strength with 14 and each pole 1
By selectively meshing the ratchets 3 and 14 with the ratchet 11d, it is possible to compensate for an increase in pitch and finely adjust the tilt angle of the seat back 21.

On the other hand, in the reclining device 10, as a means for rotatably supporting the upper arm 11 on the lower arm 12, the second recessed portions 11c provided on the upper arm 11 are provided on the lower arm 12 at both second protrusions 12c.
The means to fit 1, 12c2 is adopted. For this reason,
As compared with the case where the upper arm 11 is supported by the hinge pin, the diameter of the supporting portion is large, the supporting strength is high, and the reclining strength can be improved. In addition, as a result, the operation shaft 15 is moved through the through holes 11f and 12d of both arms 11 and 12.
It is possible to adopt a means for providing free play to selectively engage the pawls 13 and 14 with the ratchet 11d without any trouble.

Further, in the reclining device 10, the first recess 11b of the upper arm 11 is fitted to both the first protrusions 12b1 and 12b2 of the lower arm 12 with a small clearance secured. Therefore, when the seat 20 is in a normal state, the ratchet 11d does not come into contact with both the first protrusions 12b1 and 12b2, but when an excessive load is applied to the seat back 21, the tooth tips of the ratchet 11d are moved. Since the protrusions 12b1 and 12b2 are supported by abutting the outer circumferences thereof, the load of the seat back 21 is distributed to both protrusions 12b1 and 12b2 of the lower arm 12 in addition to the meshing portion between the ratchet 11d and one pole 13 or 14. Therefore, the reclining strength can be further improved.

Further, in the reclining device 10, since the ratchet 11d is formed in a ring shape so that the pawls 13 and 14 can be meshed with any position of the entire circumference of the ratchet 11d, the upper arm 11 can be rotated. By appropriately selecting the setting position of the restricting stopper, the inclination angle of the seat back 21 in the front-rear direction can be set in an arbitrary range from a wide range to a narrow range, and a variety of types of vehicle reclining seats can be obtained. Can be applied. In the reclining device 10, the holding pin 19a that holds the both arms 11 and 12 is used as a stopper that restricts the rotation range of the upper arm 11.

The above description is an example of a seat in which one of the left and right sides of the seat back 21 is supported using the reclining device 10 and the other side is supported using a simple hinge pin. When both the left and right sides of 21 are supported by using the reclining devices 10 and 10A, as shown in FIG.
5A may be connected by a connecting rod 19c so that torque can be transmitted. The right reclining device 10A has the same structure as the left reclining device 10 except that it does not include the operation lever 16. The first connection has serrations formed on the inner end side of the operation shaft 15A. The connecting rod 19c is provided with a portion 15b, and both operation shafts 15 and 1 are provided on the inner periphery of each end of the connecting rod 19c.
Each of the first connecting portions 15b of 5A is provided with a serration 19d that can be fitted with serrations. Therefore, both operating shafts 1
Reference numerals 5 and 15A are connected to each other by a connecting rod 19c so that torque can be transmitted to each other, and the turning operation of the operating lever 16 is transmitted to the operating shaft 15A via the operating shaft 15 and the connecting rod 19c, so that both reclining devices 1 can be operated.
0 and 10A work together.

[Brief description of drawings]

FIG. 1 is a front view of a reclining device according to an embodiment of the present invention.

FIG. 2 is an arrow 2- of FIG. 1 in the reclining device.
It is a vertical side view seen along line 2.

FIG. 3 shows an arrow 3- of FIG. 1 in the reclining device.
It is the cross-sectional top view seen along the 3rd line.

FIG. 4 is an exploded perspective view of the reclining device.

FIG. 5 is a front view showing only a main part of the reclining device in a locked state.

FIG. 6 is a front view showing only a main part of the reclining device in an unlocked state.

FIG. 7 is a schematic perspective view (a) of a vehicle seat in which a seat back is supported by using the reclining device, and an operation shaft and a connecting rod for explaining a connection state of the left and right reclining devices in the seat. It is a part omitted perspective view (b).

[Explanation of symbols]

10, 10A ... Reclining device, 11 ... Upper arm, 11b, 11c ... Recess, 11d ... Ratchet, 12
... Lower arm, 12b1, 12b2, 12c1, 12c2 ...
Projection portion, 13, 14 ... Pole, 13a, 14a ... Arc-shaped tooth portion, 13b, 14b ... Cam surface, 13c, 14c ... Latching portion, 15, 15A ... Operation shaft, 15b ... Coupling portion, 15d,
15e ... cam follower, 16 ... operating lever, 17a,
17b ... torsion spring, 19a, 19b ... pinching pin, 19c ... connecting rod, 20 ... seat,
21 ... Seat back, 22 ... Seat cushion.

Claims (2)

[Claims] 1. A reclining device in which a lower portion of a seat back is rotatably attached to a rear portion of a seat cushion in a front-rear direction so that a tilt angle of the seat back in the front-rear direction can be adjusted. A ring-shaped ratchet having internal teeth provided on the upper arm, and a lower arm assembled to the seat cushion, fitted concentrically with the upper arm to the ratchet and rotating the upper arm in the front-rear direction. A support portion that supports the arm, a plurality of poles that are sandwiched between the arms and that can move forward and backward with respect to the inner teeth of the ratchet inside the ratchet, and both arms with respect to the ratchet. An operation shaft that penetrates concentrically and is inserted between the base end portions of each of the poles that face each other, an outer periphery of the operation shaft and the poles. The pawls are provided between the end portions and are spring-biased to hold each of the pawls in an advanced state so as to mesh with the inner teeth of the ratchet and operate by the rotational movement of the operating shaft to retract each of the pawls to move the pawl of the ratchet. A cam means for separating from the inner teeth and an operation lever connected to the operation shaft for rotating the operation shaft by a rotation operation are provided, and the respective pawls are set to selectively mesh with the ratchet. A reclining device characterized in that. 2. The reclining device according to claim 1, wherein two pawls are adopted as the pawls, and the two pawls are arranged on the diameter line inside the ratchet with the tooth pitches shifted in the circumferential direction. The reclining device, wherein the operating shaft is movable along the diameter line by a predetermined amount.