Power reclinning device for a seat

• US 5,702,155 A
• Filed: 07/27/1995
• Issued: 12/30/1997
• Est. Priority Date: 07/29/1994
• Status: Expired due to Term

• Current Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Original Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Inventors: Ito, Sadao
• Primary Examiner(s): Nelson, Jr., Milton
• Application Number:
  US08/508,337
• Time in Patent Office: 887 Days
• Field of Search: 297/362.11, 297/362, 297/361.1, 297/354.12, 297/354.1
• US Class Current: 297/362.11
• CPC Class Codes: B60N 2/2213 Gear wheel driven mechanism B60N2/2231, B60N2/225 take precedence

Abstract

A power reclining device for use in a seat includes a reclining mechanism for adjusting a tilt angle of a seat back frame with respect to a seat cushion frame and a pre-assembled power unit having a gear train. The pre-assembled power unit has a hole for receiving an end of a rotating shaft of the reclining mechanism when it is attached to a lower arm of the seat, whereby a gear train is established for a smooth transmission of rotational torque from an electric motor to the rotating shaft.

Claims

1. A power reclining device for use in a seat comprising:

a lower arm secured to a side rear portion of a seat cushion frame;

an upper arm secured to a side lower portion of a seat back frame;

a reclining mechanism for tilting the upper arm with respect to the lower arm including a rotatable shaft which passes through both arms, the rotatable shaft having an end and a first axis;

a pre-assembled driving mechanism for operating the reclining mechanism including an electric motor and reduction gearing connected to the electric motor, the pre-assembled driving mechanism further including a housing member which is secured to the lower arm and in which at least said reduction gearing is housed, a hole formed on the housing member and receiving the end of the rotatable shaft, and an intermediate shaft positioned in and rotatably supported by the housing member and having a second axis;

a pinion gear secured to the intermediate shaft and positioned in the housing member; and

an input gear secured to the rotatable shaft and positioned in the housing member so as to be properly meshed with the pinion gear;

wherein a predetermined distance between the first axis of the rotatable shaft and the second axis of the intermediate shaft is defined by inserting the end of the rotatable shaft into the hole of the housing member so as to attain precise meshing of the input gear with the pinion gear.

2. A power reclining device according to claim 1, further comprising a sub-bracket secured to the lower arm, and wherein the rotatable shaft has eccentric and concentric portions, and the reclining mechanism includes an internal gear provided on one of the upper arm and the sub-bracket and journalled on the eccentric portion of the rotatable shaft, and an external gear provided on the other of the upper arm and the sub-bracket and adapted for partially meshing engagement with the internal gear, the external gear being journalled on the concentric portion of the rotatable shaft.

3. A power reclining device for use in a seat comprising:

a lower arm secured to a side rear portion of a seat cushion frame;

an upper arm secured to a side lower portion of a seat back frame;

a reclining mechanism for tilting the upper arm with respect to the lower arm including a rotatable shaft which passes through both arms, the rotatable shaft having a first end and a first axis;

a pre-assembled driving mechanism for operating the reclining mechanism including an electric motor, reduction gearing connected to the electric motor, an intermediate shaft connected to the reduction gearing and having a second end and a second axis, and a housing member in which at least said reduction gearing is housed and having a first hole to support the first end of the rotatable shaft and a second hole to support the second end of the intermediate shaft;

a pinion gear secured to the intermediate shaft and positioned near the housing member; and

an input gear secured to the rotatable shaft and positioned near the housing member so as to be properly meshed with the pinion gear;

wherein a predetermined distance between the first axis of the rotatable shaft and the second axis of the intermediate shaft is defined by the housing member so as to mesh precisely the input gear and the pinion gear.

4. A power reclining device according to claim 3, further comprising a sub-bracket secured to the lower arm, and wherein the rotatable shaft has eccentric and concentric portions, and the reclining mechanism includes an internal gear provided on one of the upper arm and the sub-bracket and journalled on the eccentric portion of the rotatable shaft, and an external gear provided on the other of the upper arm and the sub-bracket and adapted for partially meshing engagement with the internal gear, the external gear being journalled on the concentric portion of the rotatable shaft.

5. A power reclining device for use in a seat comprising:

a lower arm secured to a side rear portion of a seat cushion frame, said lower arm having a sub-bracket secured thereto;

an upper arm secured to a side lower portion of a seat back frame;

a rotatable shaft passing through both the upper and lower arms and having eccentric and concentric portions, an end and a first axis;

a reclining mechanism, said reclining mechanism including an internal gear provided on one of the upper arm and the sub-bracket and journalled on the eccentric portion of the rotatable shaft, and an external gear provided on another of the upper arm and the sub-bracket for partially meshing engagement with the internal gear, the external gear being journalled on the concentric portion of the rotatable shaft, for tilting the upper arm with respect to the lower arm about the rotatable shaft;

a pre-assembled driving mechanism for operating the reclining mechanism including an electric motor and reduction gearing connected to the electric motor, the pre-assembled driving mechanism further including a support member which is secured to the lower arm, a hole formed on the support member and receiving the end of the rotatable shaft, and an intermediate shaft positioned in and rotatably supported by the support member and having a second axis;

a pinion gear secured to the intermediate shaft and positioned in the support member; and

an input gear secured to the rotatable shaft and positioned in the support member so as to be properly meshed with the pinion gear;

wherein a predetermined distance between the first axis of the rotatable shaft and the second axis of the intermediate shaft is defined by the support member with the end of the rotatable shaft inserted into the hole of the support member.

6. A power reclining device for use in a seat comprising:

a lower arm secured to a side rear portion of a seat cushion frame, said lower arm having a sub-bracket secured thereto;

an upper arm secured to a side lower portion of a seat back frame;

a reclining mechanism for tilting the upper arm with respect to the lower arm, the reclining mechanism having a rotatable shaft having eccentric and concentric portions, which passes through both arms, the rotatable shaft having a first end and a first axis, includes an internal gear provided on one of the upper arm and the sub-bracket and journalled on the eccentric portion of the rotatable shaft, and an external gear provided on the other of the upper arm and the sub-bracket and adapted for partially meshing engagement with the internal gear, the external gear being journalled on the concentric portion of the rotatable shaft;

a pre-assembled driving mechanism for operating the reclining mechanism including an electric motor, reduction gearing connected to the electric motor, an intermediate shaft connected to the reduction gearing and having a second end and a second axis, and a single support member having a first hole to support the first end of the rotatable shaft and a second hole to support the second end of the intermediate shaft;

a pinion gear secured to the intermediate shaft; and

an input gear secured to the rotatable shaft and meshing with the pinion gear;

wherein a predetermined distance between the first axis of the rotatable shaft and the second axis of the intermediate shaft is defined by the support member so as to mesh precisely the input gear with the pinion gear.