JP2002355137A - Reclining device for seat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the operability of a reclining seat and prevent rattles in the taumel mechanism without complicating the structure. SOLUTION: A shaft hole 18 of an internal gear is formed at protruding bosses 22, around which an eccentric cam 24 is rotatably fitted around the boss while forming a ring hole 30 as a long hole in between. In the eccentric cam provided with an external gear on the periphery thereof, the thickest part 24a from the center has a wedge space 34 being connected to the ring hole. The wedge space is disposed with an engagement protrusion 36 which is integrated with a support shaft 20, a pair of steel balls 38-1 and 38-2 placed between across the engagement protrusion, and locking springs 40-1 and 40-2 which bias and press these balls toward a direction of narrow space formed between the boss peripheral surface 22a and the wedge guide surface 34a opposing therto with a space so that the wedge effect can be secured between the boss peripheral surface and the wedge guide surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seat reclining device capable of arbitrarily adjusting a tilt angle of a seat back, and more particularly, to a seat reclining device capable of continuously adjusting a seat using a so-called Taumel mechanism.

[0002]

2. Description of the Related Art An internal gear and a combination of the internal gear and an external gear having a small number of teeth having different numbers of teeth are provided. There is known a seat reclining device using a so-called Taumel mechanism, in which the angle can be adjusted and set steplessly.

In a reclining device using this taumel mechanism, backlash at the meshing portion between the internal gear and the external gear and rattling due to clearance around the eccentric cam are inevitable. For example, it is disclosed in JP-A-2000-225032 or JP-A-08-056768.

[0004] In each of the known structures, a fixing member,
By inserting a member functioning as a wedge between the movable members, for example, the external gear is pressed in the direction of meshing with the internal gear. According to these configurations, the wedge effect of this member prevents rattling. Peel off.

[0005]

However, since all of the members functioning as wedges used in these known structures are provided with sliding contact with the surroundings, they are not used during driving. The generation of the frictional resistance is inevitable. That is, since the operating force of the rotating operation at the time of driving tends to be heavy due to the frictional resistance, it cannot be denied that the operability is reduced.

[0006] In a known construction, a member functioning as a wedge and a spring member attached thereto are provided around the eccentric cam and at a position protruding in the axial direction of the support shaft, that is, outside the eccentric cam. Due to the configuration, the number of parts is large, and the configuration is inevitably complicated and large.

[0007] The present invention prevents rattling in the Taumeru mechanism without complicating the configuration and the like.
An object of the present invention is to provide a seat reclining device that improves its operability.

[0008]

According to the present invention, there is provided a boss hole in which one of an internal gear and an external gear is formed in a projecting boss through which a support shaft is inserted. The annular mounting hole of the eccentric cam rotatably mounted around the boss is an elongated hole extending on an assumed straight line that continuously passes through the axial center of the annular mounting hole and the axial center of the eccentric cam itself. Is formed. Further, the eccentric cam is formed having a wedge space continuous with the ring mounting hole at its maximum eccentric portion, and is provided with an engagement projection provided integrally with the support shaft, and is disposed with the engagement projection interposed therebetween. A pair of rolling engaging elements and a lock spring biasing and pressing the rolling engaging elements in a narrow position direction between the peripheral surface of the boss and the wedge guide surface spaced apart from the boss are respectively disposed in the wedge space. Have been.

[0009] The internal gear and the external gear are locked by the wedge effect by the forcible movement of the eccentric cam with respect to the boss when the rolling engagement element is fitted into the narrow position, and the rotation of the support shaft is started. In addition, by the pressing of one of the rolling engagement members against the biasing force of the lock spring by the engagement projection,
The lock by the wedge effect of the pair of rolling engagement elements is released, and by the subsequent rotation operation of the support shaft in the corresponding direction,
The eccentric cam is rotated around the boss with the rolling of the other rolling engagement element.

[0010]

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

As shown in FIG. 1, a seat reclining device 10 according to the present invention uses a so-called Taumel mechanism having a combination of an internal gear 12 and a small-diameter external gear 14 having a smaller number of teeth than the internal gear. Thus, it is configured to be capable of stepless adjustment.

The internal gear 12 is formed, for example, on the peripheral surface of a circular concave portion 17 provided in the first base member 16, and as can be seen from FIG. 2 in addition to FIG. A support shaft 20 is supported by being inserted into a shaft hole 18 formed therearound.

In the present invention, the shaft hole 18
Are formed as boss holes formed in the protruding boss 22, and an eccentric cam 24 is rotatably mounted around the boss.

The external gear 14 is formed, for example, on the peripheral surface of a circular convex portion 27 provided on the second base member 26. An insertion hole 28 is formed.

The eccentric cam 24 has a ring mounting hole 30 having the axis 01 of the internal gear as its axis. The eccentric cam 24 is mounted around the boss with the boss 22 inserted through the ring mounting hole. Is done. That is, in this configuration, the axis 02 of the eccentric cam itself is displaced from the axis 01 of the annular mounting hole 30 of the eccentric cam.
24 is around the boss 22 inserted in the ring hole, that is, the axis
Since the eccentric cam rotates with the support shaft 20, the external gear 14 around the eccentric cam eccentrically moves in the internal gear 12, and the eccentric cam rotates around the eccentric cam. , The second base member on which the external gear is formed
26 is rotated with respect to the first base member 16.

In such a reclining device 10, usually, the first base member 16 is fixed to the seat cushion, and the second base member 26 is fixed to the seat back, so that the seat (not shown) is fixed. Attached.

Incidentally, the basic configuration and the basic operation of such a Taumel mechanism are described in, for example, JP-A-2000-2250.
It is publicly known as disclosed in Japanese Patent Publication No. 32 or Japanese Unexamined Patent Application Publication No. 08-056768, and the basic configuration and basic operation thereof are not the purpose of the present invention.

By the way, as can be seen from FIG. 2, in the present invention, the ring mounting hole 30 of the eccentric cam is formed by the axis of the ring mounting hole, that is, the axis 01 of the internal gear and the axis of the eccentric cam 24 itself. The shaft, that is, is formed as an elongated hole extending on an assumed straight line 32 continuously passing through the shaft 02 of the external gear, and the eccentric cam is
The wedge space 34 continuous with the ring hole is formed by the maximum eccentric portion 24a.
Is formed. As can be seen from FIG. 1 in addition to FIG. 2, an engagement projection 36 provided integrally with the support shaft 20, and a pair of rolling engagement elements 38-1 arranged with the engagement projection interposed therebetween. , 38-2, and lock springs 40-1, 40-2 for biasing and pressing this rolling engagement element in the direction of the narrow position between the boss peripheral surface 22a and the wedge guide surface 34a opposed to the boss peripheral surface 22a, Inside the wedge space 34, they are respectively provided.

As can be seen from FIG. 1, the support shaft 20 is formed integrally with, for example, a flange-like support piece 42, and an engagement protrusion 36 is provided on a part of the support piece. ing. The engagement protrusion 36 is engaged with the rolling engagement elements 38-1 and 38-2, and is rotatable integrally with the support shaft 20 around the boss 22 so that the engagement protrusion 36 is engaged with the boss peripheral surface 22a. It is arranged with a predetermined clearance therebetween.

The engaging projection 36 is formed in a wedge space of the eccentric cam.
Since the inside of the wedge space is moved within its movable range, a similar clearance is provided between the wedge space and the wedge guide surface 34a.

As the rolling engagement elements 38-1 and 38-2, for example, steel balls can be exemplified. Also, lock spring 40
A compression coil spring can be exemplified as -1,40-2.

As shown in FIG. 2A, steel balls (rolling engagement members) 38-1 and 38-2 are provided with respective lock springs 40-38.
Under the biasing force of 1,40-2, they are biased and pressed in the direction of the narrow position between the boss peripheral surface 22a and the wedge guide surface 34a, that is, in the direction of the engagement projection 36. The narrow position between the boss peripheral surface 22a and the wedge guide surface 34a is
According to this configuration, each steel ball is formed with the boss peripheral surface 22a and the wedge under the biasing force of the lock springs 40-1 and 40-2. Since it is fitted in a wedge shape at a narrow position between the eccentric cam 24 and the guide surface 34a,
However, the boss 22, that is, the first base member 16 having the internal gear 12 is
In contrast, the second base member 26 having the external gear 14 is forcibly moved upward in the drawing, that is, in the direction in which the external gear meshes with the internal gear.

That is, according to the present invention, the boss peripheral surface 22
a, steel balls 38-1, 3 between wedge guide surfaces 34a
Due to the wedge effect of 8-2, the external gear 14
Is forcibly pressed and locked, thereby reliably preventing backlash of the meshing portion between the internal gear and the external gear and rattling due to clearance around the eccentric cam.

From such a locked state, the support shaft
20, for example, an operating handle at one end (not shown)
By rotating the lock spring 40-2 in an arbitrary direction, for example, clockwise in FIG. 2, the locking projection 40-2 due to the engagement protrusion 36 accompanying the rotation start shown in FIG. By pressing the steel ball 38-2, a pair of steel balls 38
The lock by the wedge effect in -1,38-2 is released first. Then, the support shaft is moved in the corresponding direction, that is, clockwise in the figure.
By further rotating the eccentric cam 20, as shown in FIG. 2C, the engaging projection 36 presses the eccentric cam 24 in the corresponding direction (clockwise in the drawing) at the movable limit position, so that the eccentric The eccentric movement of the cam and thus the external gear 14 is ensured.

At this time, the other steel ball 38-1, which is not pressed by the engagement projection 36, is biased to a narrow position between the boss peripheral surface 22a and the wedge guide surface 34a under the biasing force of the lock spring 40-1. , Has been retained. In other words, this boss 22
The rotation of the eccentric cam 24 around this other steel ball
Since it is accompanied by the rolling of 38-1, the weight of the rotating operation force can be reduced.

As described above, the seat reclining device 10 of the present invention includes the engagement projection 36, the steel balls 38-1, 38-2, and the lock spring 40-1 disposed in the wedge space 34 of the eccentric cam. , 40-2, the lock is obtained by the wedge effect, so that the mechanical section can be reliably prevented from being enlarged. Then, it is sufficient to dispose the engagement protrusion 36, the steel balls 38-1, 38-2, and the lock springs 40-1, 40-2 in the wedge space 34 of the eccentric cam, so that the configuration can be simplified. , And the number of parts is reliably reduced.

As described above, also in the configuration of the present invention, the lock of the external gear 14 with respect to the internal gear 12 is
a, steel balls 38-1, 3 between wedge guide surfaces 34a
According to the present invention, it is possible to reduce the rotational operation force by rolling the steel balls when the support shaft 20 is rotated. Therefore, according to the present invention, it is possible to prevent rattling in the taumel mechanism and improve operability thereof without complicating the configuration and enlarging the configuration.

In the embodiment of the present invention,
Although the example in which the support shaft 20 is rotated clockwise in the drawing is embodied, the same operation and effect can be obtained by rotating the support shaft 20 counterclockwise in the drawing. It goes without saying that it can be obtained.

Reference numerals 44 and 45 shown in FIG.
A cover plate that prevents separation between the base member 16 and the second base member 26, a cover plate 44 is provided on the first base member from outside the second base member, and a cover plate 45 is provided on the first base member. Are fixed to the second base member from outside.

In this embodiment, an example is shown in which the internal gear 12 is formed on the first base member 16 and the external gear 14 is formed on the second base member 26, respectively. For example, the internal gear may be formed on the second base member, and the external gear may be formed on the first base member. Further, here, the support shaft 20 is disposed on the shaft center 01 of the internal gear 12, but the present invention is not limited to this.

Further, in this embodiment, the first base member 16 is arranged on the seat cushion side and the second base member 26 is arranged on the seat back side. It is enough to be able to tilt the seat back, so it is not limited to this,
For example, the first base member is on the seat back side,
The second base member may be arranged on the seat cushion side.

In the embodiment of the present invention,
The steel balls 38-1 and 38-2 are embodied as rolling engaging elements, but the rolling engaging elements are the boss peripheral surface 22a and the wedge guide surface 3.
It is only necessary to be able to roll between 4a, so it is not limited to steel balls. For example, a roller may be used as the rolling engaging element.

However, steel balls 38-1, 38-2
In (2), since the rolling direction is not limited, smooth rolling can be easily ensured. Therefore, the operability defect can be reliably prevented.

The embodiments described above are for explaining the present invention, and do not limit the present invention in any way. All the modifications and alterations within the technical scope of the present invention are not limited thereto. It goes without saying that it is included in the invention.

[0035]

As described above, according to the seat reclining apparatus of the present invention, the engagement projection, the pair of rolling engagement elements, and the pair of lock springs disposed in the wedge space of the eccentric cam are used. Since the lock by the wedge effect can be obtained, rattling in the taumel mechanism can be prevented without increasing the size and complicating the configuration.

The other rolling engagement element, which is not pressed by the engagement projection, is biased and held at a narrow position between the boss peripheral surface and the wedge guide surface under the biasing force of the lock spring. Since the rotation of the eccentric cam around the boss is accompanied by the rolling of the other rolling engagement element, it is possible to simultaneously reduce the weight of the rotating operation force.

Further, if a steel ball having no limitation on the rolling direction is used as the rolling engaging element, smooth rolling can be easily ensured, so that the operability problem can be surely prevented.

[Brief description of the drawings]

FIG. 1 is a schematic exploded perspective view of a seat reclining device according to the present invention.

FIG. 2 is a schematic operation diagram of a seat reclining device.

[Explanation of symbols]

 10 Seat reclining device 12 Internal gear 14 External gear 16 First base member 22 Boss 24 Eccentric cam 26 Second base member 30 Ring hole 34 Wedge space 36 Engagement projection 38-1,38-2 Steel ball (rolling 40-1) 40-2 lock spring

Claims (2)

[Claims] An internal gear is provided on one of first and second base members rotatably coupled via a support shaft, and a small-diameter external gear having fewer teeth than the internal gear is provided on the other. With the eccentric rotation of the eccentric cam, which is formed separately from the support shaft and its shaft center, one of the internal gear and the external gear with the support shaft arranged on the shaft center, the other around the eccentric cam In a seat reclining device capable of steplessly adjusting the angle of a second base member with respect to a first base member by eccentric movement, one of a shaft hole of an internal gear or an external gear into which a support shaft is inserted has a projecting shape. An assumed straight line that is formed as a boss hole formed in the boss, and the ring hole of the eccentric cam rotatably mounted around the boss continuously passes through the axis of the ring hole and the axis of the eccentric cam itself. The eccentric cam is formed as an elongated hole A wedge space continuous with the mounting hole, formed at the maximum eccentric portion thereof, formed with an engagement projection provided integrally with the support shaft, a pair of rolling engagement elements disposed so as to sandwich the engagement projection, A lock spring that biases and presses the rolling engagement element in a narrow position direction between the boss peripheral surface and the wedge guide surface that is separated from and opposed to the boss peripheral surface and is smaller than the diameter of the rolling engagement element is provided in the wedge space. The internal gear and the external gear are locked by the wedge effect by the forcible movement of the eccentric cam with respect to the boss when the rolling engagement element is fitted into the narrow position, and the rotation of the support shaft is started. In addition, the engagement projection presses one of the rolling engaging elements against the biasing force of the lock spring, thereby releasing the lock by the wedge effect of the pair of rolling engaging elements, and thereafter moving the support shaft in the corresponding direction. Rotation of the other rolling engagement element The accompanying sheet of reclining apparatus is characterized in that rotating the eccentric cam around the boss. 2. The seat reclining device according to claim 1, wherein the rolling engagement element is a steel ball.