JPH0742347Y2 - Reclining device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an eccentric part and a concentric part of a shaft that is driven to rotate by a motor when adjusting a reclining angle, an external gear of a lower arm, and an external gear that meshes with the external gear. The present invention relates to a reclining device having a configuration in which an internal gear of an upper arm having a larger number of teeth than an external gear is rotatably inserted.

(Prior Art) In this type of reclining device, a shaft,
A planetary gear mechanism is composed of a lower arm formed with an external gear and an upper arm formed with an internal gear, and a shaft is rotated by a motor to decelerate and rotate the upper arm, so that the seatback attached to the upper arm is rotated. It is designed to tilt and adjust the reclining angle. Power transmission from the motor to the shaft is performed by an external gear train including a pinion attached to the output shaft of the motor and a driven gear circumscribing the pinion and having a central portion fitted to the spline portion of the shaft.

(Problems to be solved by the invention) In the case of the conventional reclining device as described above, in order to prevent the driven gear from coming off from the spline portion of the shaft, a male screw portion is continuously provided on the spline portion of the shaft to drive the driven gear. Assembly of the gear to the shaft is performed by fitting the driven gear to the spline portion of the shaft, pressing a washer, and then screwing and fixing the nut.

Therefore, there are problems that the number of parts is large and the cost of parts is high. In addition, since work such as screwing a nut into a cylindrical shaft is required, there is a problem in that assembly workability is poor.

The present invention has been made in view of such problems, and an object thereof is to provide a reclining device having a small number of parts, a low part cost, and good workability in assembling. Another object of the present invention is to provide a reclining device that can be reduced in weight.

(Means for Solving the Problems) The present invention for solving the above problems includes a shaft having a concentric part and an eccentric part, a spline part formed in a part of the concentric part, and an external gear. A center of the external gear is rotatably fitted to the eccentric part of the shaft, and an internal gear having a larger number of teeth than the external gear by meshing with the external gear of the lower arm is formed. An upper arm whose part is rotatably fitted to a concentric part of the shaft, and a motor which is attached to the upper arm in a direction such that the output shaft projects toward the upper arm side and is driven when the reclining angle is adjusted. A rib is provided on at least the upper arm side portion of the pinion attached to the output shaft of the motor and the tooth portion circumscribing the pinion,
In addition, the center portion is provided with a driven gear made of synthetic resin fitted to the spline portion of the shaft.

(Operation) In the reclining device of the present invention, when the motor rotates, the pinion and the driven gear rotate, and the shaft rotates.
Therefore, the upper arm tilts and the reclining angle changes. When the driven gear tries to move in the direction of coming out of the shaft, the rib provided on the tooth portion of the driven gear comes into contact with the end portion of the pinion and restricts the movement in this direction.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. This embodiment is an example of a double-sided reclining device,
It has a drive-side reclining mechanism (left side in FIG. 1) and a driven-side reclining mechanism (right side in FIG. 1). First, the reclining mechanism on the drive side will be described.

An external gear 1a is embossed by a precision embossing press or the like on one side surface of the lower arm 1 which is fixed to the seat cushion side (a seat cushion frame not shown) with screws or the like. A tapered through hole 1b is formed. On the side surface of the upper arm 2 disposed adjacent to the lower arm 1 facing the external gear 1a of the lower arm 1, an internal gear 2a meshing with the external gear 1a and having more teeth than the external gear 1a is precision embossed. It is embossed by pressing. A through hole 2b is formed in the center of the external gear 2a. The upper arm 2 is rivet-attached to the seat back arm fitting 3 with rivets 14 so that the upper arm 2 and the lower arm 1 are sandwiched by the upper arm 2 and the lower arm 1. The seat back arm fitting 3 is fixed to the seat back side (seat back frame not shown) with screws or the like, and is provided at a position coaxial with the through hole 2b of the upper arm 2.
A through hole 3a is formed, and the bush 4 is press-fitted into this through hole 3a.

Eccentric part 5 of shaft 5 having concentric parts 5a, 5b and eccentric part 5c
The c is composed of a taper ring 6 whose outer peripheral surface is tapered, and the taper ring 6 is movable in the axial direction with respect to the shaft 5 main body. The concentric parts 5a, 5b of the shaft 5 are rotatably fitted in the through hole 2b of the upper arm 2 and the bush 4, and the eccentric part 5c (taper ring 6) of the shaft 5 is fitted in the through hole 1b of the lower arm 1. Is rotatably fitted.

With the above configuration, the upper arm 2 and the lower arm 1
It is rotatably attached to the concentric portion 5a and the eccentric portion 5c (taper ring 6) of the shaft 5, and the outer gear 1a and the inner gear 2a are meshed with each other, so that the lower arm 1, the upper arm 2, and the shaft 5 form a planetary gear mechanism. Make up. In the space between the lower arm 1 and the seat back arm fitting 3, an annular elastic body 7 sandwiched by a washer 15 is arranged coaxially with the eccentric portion 5c of the shaft 5 in a compressed state. With the elastic body 7,
An elastic force in the right direction in FIG. 1 is applied to the taper ring 6. As a result, the taper ring 6 is driven as a wedge between the main body of the shaft 5 and the through hole 1b of the lower arm 1. In the state shown in FIG. 1, the shaft 5 and the upper arm 2 receive a downward pressing force. ing. Therefore, the meshing portion between the external gear 1a and the internal gear 2a receives a pressing force in the meshing direction. Therefore, there is no backlash, and an occupant does not feel uncomfortable and no abnormal noise is generated.

The motor 8 with a built-in gearbox is driven when adjusting the reclining angle.
It is attached to the upper arm 2 in a direction such that the 8a projects toward the upper arm 2 side. Specifically, the motor 8 is fixed to the mounting member 9 with bolts 16, and the mounting member 9 is fixed to the upper arm 2 with screws 17. The tip of the output shaft 8a of the motor 8 is inserted into and supported by a bush 10 which is press-fitted into the upper arm 2, and the pinion 11 is provided in the middle.
Is attached. The driven gear 12 made of synthetic resin is in external contact with the pinion 11, and a rib 12b is provided on at least a portion of the tooth portion 12a on the upper arm 2 side.
The center portion is fitted to the spline portion 5d of the shaft 5. One end of a connecting shaft 13 is fitted to the other spline portion 5e of the shaft 5. The other end of the connecting shaft 13 is fitted into the reclining mechanism on the driven side.

Since the driven-side reclining mechanism is merely the motor 8, the pinion 11, the driven gear 12 and the like removed from the driving-side reclining mechanism, the other components are simply arranged symmetrically with respect to the driving-side reclining mechanism. The members corresponding to the components of the reclining mechanism on the side are allotted with the same numbers with a dash “′” in FIG. 1, and the description thereof is omitted.

In the above structure, the assembling is performed as follows. First, the bush 10 is press-fitted into the seat back arm fitting 3, and the seat back arm fitting 3 and the elastic body are attached to the shaft 5.
7, the lower arm 1 and the upper arm 2 are stacked in this order, and the seat back arm fitting 3 and the upper arm 2 are fixed with the rivet 14. Next, after fitting the driven gear 12 of the serration portion 5d of the shaft 5, the motor 8 is attached to the upper arm 2 using the attachment fitting 9 in such a state that the pinion 11 meshes with the driven gear 12.

Next, the operation of the above embodiment will be described.

The operation itself as the reclining device of this embodiment is the same as that of the conventional device. When the motor 8 rotates, the pinion 11 and the driven gear 12 rotate, and the shaft 5 rotates.
Therefore, the upper arm 2 tilts and the reclining angle can be adjusted.

The operational feature of the present invention appears when the driven gear 12 attempts to move away from the shaft 5. That is,
When the driven gear 12 tries to move in this direction, the driven gear 12
The ribs 12b provided on the twelve tooth portions 12a come into contact with the end portions of the pinion 11 and regulate the movement in this direction.

In this way, it is possible to prevent the driven gear 12 from slipping off the shaft 5 only by providing the rib 12b on the upper arm 2 side portion of the tooth portion 12a of the driven gear 12, so that the spline portion 5d of the shaft 5 can be prevented from coming off from the shaft 5 as in the conventional case. When the driven gear 12 is assembled to the shaft 5, the driven gear is continuously provided with male threads.
After fitting 12 to the spline portion 5d of the shaft 5, a work such as pressing a washer and screwing in a nut to fix is unnecessary. Therefore, the number of parts is small, the parts cost is low, and the assembling workability is improved.

Further, by providing the rib 12b, the strength of the tooth portion 12a of the driven gear 12 can be increased, so that the driven gear 12 can be made of synthetic resin, and also in this respect, the cost of parts can be reduced, and further, Can be made lighter.

The present invention is not limited to the above embodiment, but various modifications can be made. For example, as shown in FIG. 3, the driven gear 12 may be one in which ribs 12b are provided on both sides of the tooth portion 12a.

(Effect of the Invention) As described above, according to the present invention, it is possible to realize a reclining device having a small number of parts, a low part cost, and good workability in assembling.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention AA in FIG.
FIG. 2 is an enlarged sectional view, FIG. 2 is a side view showing an embodiment of the present invention, and FIG. 3 is a sectional view showing another constitutional example of the driven gear. 1 ... Lower arm, 1a ... External gear 1b, 2b, 3a ... Through hole 2 ... Upper arm, 2a ... Internal gear 3 ... Seatback arm bracket 4,10 ... Bushing 5 ... Shaft 5a, 5b ... Concentric part 5c ... Eccentric part , 5d ... Spline part 6 ... Tapered ring, 8 ... Motor 8a ... Output shaft, 9 ... Mounting bracket 11 ... Pinion, 12 ... Driven gear 12a ... Tooth portion, 12b ... Rib 13 ... Connecting shaft

Claims (1)

[Scope of utility model registration request] 1. A shaft having a concentric part and an eccentric part, and a spline part formed in a part of the concentric part, and an external gear formed so that the center part of the external gear is rotatable to the eccentric part of the shaft. And a lower arm fitted to the lower arm, and an internal gear having a larger number of teeth than the external gear by meshing with the external gear of the lower arm is formed, and a central portion of the internal gear is rotatably fitted to a concentric portion of the shaft. An upper arm, a motor attached to the upper arm in a direction such that the output shaft projects toward the upper arm and driven when the reclining angle is adjusted, a pinion attached to the output shaft of the motor, and the pinion. A driven gear made of synthetic resin, wherein a rib is provided on at least a portion of the tooth portion circumscribing to the upper arm side, and a central portion of which is fitted to a spline portion of the shaft. Reclining apparatus according to claim that there were example.