Anti-tip system for a power wheelchair

Patent metadata

Field	Value
Publication number	US-9526664-B2
Application number	US-201414504259-A
Country	US
Kind code	B2
Filing date	Oct 1, 2014
Priority date	Oct 8, 2003
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

An anti-tip system is provided for improving the stability of a powered vehicle, such as a powered wheelchair. The vehicle includes a drive-train assembly pivotally mounted to a main structural frame. A suspension system biases the drive-train assembly and its connected anti-tip wheel to a predetermined resting position. The drive-train assembly bi-directionally rotates about a pivot in response to torque applied to or acceleration forces on the vehicle. A linkage arrangement is provided and is characterized by a suspension arm pivotally mounting to the main structural frame about a pivot at one end thereof and an anti-tip wheel at the other end. The linkage may further include at least one link operable to transfer the bi-directional displacement of the drive-train assembly to the suspension arm. The link may include a bell crank member and/or may be resiliently compressible.

First claim

What is claimed:

1. A powered vehicle comprising:
a frame;
a seat mounted on the frame;
a pair of drive wheels positioned on opposing sides of the frame;
a drive motor assembly operatively coupled to at least one of the drive wheels for powering rotation of the drive wheel about a drive wheel axis and for powering movement of the vehicle across a ground plane;
a mounting plate pivotably coupled to the frame, the mounting plate being coupled to the drive motor assembly;
at least one anti-tip assembly comprising a suspension arm pivotably mounted to the frame at a suspension arm pivot axis, said suspension arm extending from said suspension arm pivot axis outwardly from the frame, said suspension arm pivot axis vertically spaced above the ground plane, the at least one anti-tip assembly further including an anti-tip wheel assembly coupled to the suspension arm, the anti-tip wheel assembly including an anti-tip wheel that is in contact with the ground plane during normal operation of the powered vehicle and having a rotational axis about which the anti-tip wheel rotates; and
a resilient link operatively connected to the mounting plate and the suspension arm so as to operatively connect the drive motor assembly to the suspension arm,
wherein, in response to torque created by the motor in rotating the drive wheel, the drive motor assembly pivots about the motor pivot axis, causing through the operative connection of the resilient link the suspension arm to pivot about the suspension arm pivot axis, and causing a corresponding movement of the anti-tip wheel,
wherein the resilient link includes a first link member and a second link member, wherein a pin is one of the first and second link members and a slot is the other of the first and second link members, where the pin is moveable in the slot in response to torque created by the motor in rotating the drive wheel.

2. The powered vehicle of claim 1 wherein the resilient link has a fixed maximum length and is resiliently compressible.

3. The powered vehicle of claim 1 said suspension arm pivot axis being spaced below the drive wheel axis.

4. The powered vehicle of claim 1 , wherein the motor pivot axis is vertically aligned with the suspension arm pivot axis.

5. The powered vehicle of claim 1 wherein, in response to torque created by the motor in rotating the drive wheel, the rotational axis of the anti-tip wheel is spatially located at a vertical position with respect to the ground plane substantially equal to or above the vertical position of the suspension arm pivot axis relative to the ground plane.

6. A powered vehicle comprising:
a frame;
a seat mounted on the frame;
a pair of drive wheels positioned on opposing sides of the frame;
a drive motor assembly operatively coupled to at least one of the drive wheels for powering rotation of the drive wheel about a drive wheel axis and for powering movement of the vehicle across a ground plane;
a mounting plate pivotably coupled to the frame, the mounting plate being coupled to the drive motor assembly;
at least one anti-tip assembly comprising a suspension arm pivotably mounted to the frame at a suspension arm pivot axis, said suspension arm extending from said suspension arm pivot axis outwardly from the frame, said suspension arm pivot axis vertically spaced above the ground plane, and said suspension arm pivot axis being spaced below the drive wheel axis, the at least one anti-tip assembly further including an anti-tip wheel assembly coupled to the suspension arm, the anti-tip wheel assembly including an anti-tip wheel that is in contact with the ground plane during normal operation of the powered vehicle and having a rotational axis about which the anti-tip wheel rotates; and
a resilient link operatively connected to the mounting plate and the suspension arm so as to operatively connect the drive motor assembly to the suspension arm,
wherein, in response to torque created by the motor in rotating the drive wheel, the drive motor assembly pivots about the motor pivot axis, causing through the operative connection of the resilient link the suspension arm to pivot about the suspension arm pivot axis, and causing a corresponding movement of the anti-tip wheel.

7. The powered vehicle of claim 6 , wherein the resilient link includes a first link member and a second link member, wherein a pin is one of the first and second link members and a slot is the other of the first and second link members, where the pin is moveable in the slot in response to torque created by the motor in rotating the drive wheel.

8. A powered vehicle comprising:
a frame;
a seat mounted on the frame;
a pair of drive wheels positioned on opposing sides of the frame;
a drive motor assembly operatively coupled to at least one of the drive wheels for powering rotation of the drive wheel about a drive wheel axis and for powering movement of the vehicle across a ground plane;
a mounting plate pivotably coupled to the frame, the mounting plate being coupled to the drive motor assembly;
at least one anti-tip assembly comprising a suspension arm pivotably mounted to the frame at a suspension arm pivot axis, said suspension arm extending from said suspension arm pivot axis outwardly from the frame, said suspension arm pivot axis vertically spaced above the ground plane, wherein the motor pivot axis is vertically aligned with the suspension arm pivot axis, and the at least one anti-tip assembly further including an anti-tip wheel assembly coupled to the suspension arm, the anti-tip wheel assembly including an anti-tip wheel that is in contact with the ground plane during normal operation of the powered vehicle and having a rotational axis about which the anti-top wheel rotates; and
a resilient link operatively connected to the mounting plate and the suspension arm so as to operatively connect the drive motor assembly to the suspension arm,
wherein, in response to torque created by the motor in rotating the drive wheel, the drive motor assembly pivots about the motor pivot axis, causing through the operative connection of the resilient link the suspension arm to pivot about the suspension arm pivot axis, and causing a corresponding movement of the anti-tip wheel.

9. The powered vehicle of claim 8 , wherein the resilient link includes a first link member and a second link member, wherein a pin is one of the first and second link members and a slot is the other of the first and second link members, where the pin is moveable in the slot in response to torque created by the motor in rotating the drive wheel.

10. A powered vehicle comprising:
a frame;
a seat mounted on the frame;
a pair of drive wheels positioned on opposing sides of the frame;
a drive motor assembly operatively coupled to at least one of the drive wheels for powering rotation of the drive wheel about a drive wheel axis and for powering movement of the vehicle across a ground plane;
a mounting plate pivotably coupled to the frame, the mounting plate being coupled to the drive motor assembly;
at least one anti-tip assembly comprising a suspension arm pivotably mounted to the frame at a suspension arm pivot axis, said suspension arm extending from said suspension arm pivot axis outwardly from the frame, said suspension arm pivot axis vertically spaced above the ground plane, the at least one anti-tip assembly further including an anti-tip wheel assembly coupled to the suspension arm, the anti-tip wheel assembly including an anti-tip wheel that is in contact with the ground plane during normal operation of the powered vehicle and having a rotational axis about which the anti-tip wheel rotates; and
a resilient link operatively connected to the mounting plate and the suspension

Assignees

• Pride Mobility Products Corp

Inventors

• Mulhern James P
• Levi Ronald
• Grymko Christopher E

Classifications

• A61G5/042 Primary

  Front wheel drive · CPC title

• A61G5/043

  Mid wheel drive · CPC title

• A61G5/06

  with obstacle mounting facilities, e.g. for climbing stairs, {kerbs or steps} · CPC title

• A61G5/1078

  with shock absorbers or other suspension arrangements between wheels and frame · CPC title

• A61G5/063

  with eccentrically mounted wheels · CPC title