Power back door bounce prevention to allow maximum opening speed

Patent metadata

Field	Value
Publication number	US-2019194999-A1
Application number	US-201715852672-A
Country	US
Kind code	A1
Filing date	Dec 22, 2017
Priority date	Dec 22, 2017
Publication date	Jun 27, 2019
Grant date	—

Abstract

A power back door for a vehicle, in which the back door is automatically opened and closed by a pair of power back door drive devices, each of the power back door drive devices including an inner tube encompassed by an outer tube; a motor; a spindle screw that is turned by the motor; a spindle nut attached to one end of the inner tube and travels up and down the spindle screw to cause the inner tube to extend and contract relative to the outer tube over a length of travel; and a stopper fixed to the end of the spindle screw to stop the movement of the spindle nut at the end of travel. A length of travel of one of the power back door drive devices is different than a length of travel of the other of the power back door drive devices allowing the power back door to be quickly opened without bouncing at full open.

First claim

1 . A power back door for a vehicle, in which the back door is automatically opened and closed by a pair of power back door drive devices, each of the power back door drive devices comprising:
an inner tube encompassed by an outer tube; a motor; a spindle screw that is turned by the motor; a spindle nut attached to one end of the inner tube and travels up and down the spindle screw to cause the inner tube to extend and contract relative to the outer tube over a length of travel; and a stopper fixed to the end of the spindle screw to stop the movement of the spindle nut at the end of travel, wherein a length of travel of one of the power back door drive devices is different than a length of travel of the other of the power back door drive devices.

2 . The power back door of claim 1 , wherein the end of the stopper of one of the power back door drive devices is located at a position in the spindle screw that is closer to the motor than the same end of the stopper of the other of the power back door drive devices.

3 . The power back door of claim 1 , wherein the end of the stopper of one of the power back door drive devices is located at a position in the spindle screw that is different from the same end of the stopper of the other of the power back door drive devices by a range of 1 to 5 mm.

4 . The power back door of claim 1 , wherein the end of the stopper of one of the power back door drive devices is located at a position in the spindle screw that is different from the same end of the stopper of the other of the power back door drive devices by substantially 5 mm.

5 . The power back door of claim 1 , wherein a length of the inner tube of one of the power back door drive devices is different than a length of the inner tube of the other of the power back door drive devices.

6 . The power back door of claim 5 , wherein the length of the inner tube of one of the power back door drive devices is shorter that the length of the inner tube of the other of the power back door drive devices by a range of 1 to 5 mm.

7 . The power back door of claim 6 , wherein the length of the inner tube of one of the power back door drive devices is shorter that the length of the inner tube of the other of the power back door drive devices by substantially 5 mm.

8 . The power back door of claim 1 , further comprising a planetary gear positioned between the motor and the spindle screw to slow the rotation of the spindle screw relative to the rotation speed of the motor.

9 . The power back door of claim 1 , wherein the back door is a hatchback-type door.

10 . The power back door of claim 1 , wherein the back door is a power lift gate.

11 . A method of operating a power back door, the power back door including a pair of power back door chive devices, each of the pair of drive devices includes an inner tube encompassed by an outer tube, a spindle nut fixed to an end of the inner tube and a stopper fixed to an end of a spindle screw, and the spindle nut screws along the spindle screw, the method comprising:
simultaneously driving each of the power back door drive devices to open position by rotating a motor; rotating the spindle screw using the output rotation of the motor; expanding the power drive unit by
screwing the spindle nut along the spindle screw to cause movement of the inner tube relative to the outer tube and in a direction away from the motor;
stopping screwing of the spindle nut when the spindle nut reaches the stopper constituting an end of a length of travel of the inner tube to a fully extended position,
wherein a length of travel of one of the power back door drive devices is different than a length of travel of the other of the power back door drive devices such that the power back door receives the impact from the power back door drive devices unevenly.

12 . The method of claim 11 , wherein the difference in length of travel between the power back door drive devices includes the spindle nut of one of the drive devices reaching the respective stopper before the spindle nut of the other of the chive devices reaches the respective stopper.

13 . The method of claim 11 , wherein the difference in length of travel between the power back door drive devices is 1 to 5 mm.

14 . The method of claim 13 , wherein the difference in length of travel between the power back door drive devices is 5 mm.

15 . The method of claim 11 , further comprising reducing the rotation speed of the motor by a planetary gear to a slower rotation speed for rotating the spindle screw.

Assignees

• Toyota Eng & Mfg North America

Inventors

• Kerr Norman C
• Sackett Jay L

Classifications

• E05F15/622 Primary

  using screw-and-nut mechanisms · CPC title

• E05Y2900/546

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• E05Y2900/548

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