Commercial electric vehicle steering
Described herein is a steering system for an electric commercial electric vehicle. The commercial electric vehicle steering system utilizes a recirculating ball steering system with a fixed height idler that allows for control of a track rod to mimic the geometry of a rack and pinion steering system. The fixed height idler includes a ball joint for distance control and a bushing to prevent rotation of the ball joint.
1 . A commercial electric vehicle steering system comprising:
a recirculating ball steering unit, configured to be coupled to a commercial electric vehicle frame and comprising a rotatable output shaft configured to rotate around an output axis;
a first tie rod;
a second tie rod;
a track rod, comprising:
a first end coupled to the first tie rod;
a second end coupled to the second tie rod;
a pitman attachment, disposed between the first end and the second end; and
an idler attachment, disposed between the first end and the second end;
a pitman arm, coupled to the rotatable output shaft and the pitman attachment;
an idler arm, coupled to the idler attachment; and
a steering idler, comprising:
a steering idler ball joint comprising:
an idler ball stud, configured to couple to the commercial electric vehicle frame and comprising a steering idler ball; and
a stud shaft, the stud shaft coupled to the idler arm and configured to rotate around a stud axis, the stud axis disposed substantially laterally in line with the output axis;
a substantially cylindrical sidewall, enclosing at least a portion of the stud shaft; and
a bushing, coupled to the stud shaft and the substantially cylindrical sidewall, containing an outside diameter of the stud shaft, and configured to prevent angular rotation of the idler ball stud.
2 . The commercial electric vehicle steering system of claim 1 , wherein the steering idler ball joint further comprises an idler ball socket, wherein the steering idler ball is disposed within the idler ball socket.
3 . The commercial electric vehicle steering system of claim 2 , wherein the idler ball socket is configured to be disposed proximate the commercial electric vehicle frame.
4 . The commercial electric vehicle steering system of claim 1 , wherein the idler arm is coupled to the idler attachment with an idler arm ball joint.
5 . The commercial electric vehicle steering system of claim 4 , wherein a first distance between the output axis and the pitman attachment is substantially similar to a second distance between the stud axis and the idler attachment.
6 . The commercial electric vehicle steering system of claim 5 , wherein the pitman arm is coupled to the pitman attachment with a pitman arm ball joint.
7 . The commercial electric vehicle steering system of claim 6 , wherein the idler arm ball joint comprises:
an idler arm ball, disposed within an idler socket of the idler arm; and
an idler arm shaft, coupled to the idler attachment.
8 . The commercial electric vehicle steering system of claim 7 , wherein the idler socket comprises a lip configured to allow less than 2 degrees of angular rotation for the idler arm ball joint.
9 . The commercial electric vehicle steering system of claim 6 , wherein the pitman arm ball joint comprises:
a pitman arm ball, disposed within a pitman socket of the pitman arm; and
a pitman arm shaft, coupled to the pitman attachment.
10 . The commercial electric vehicle steering system of claim 1 , wherein at least a portion of the stud shaft is non-tapered.
11 . A commercial electric vehicle comprising:
a commercial electric vehicle frame;
a first suspension, comprising:
a first tie rod;
a second tie rod; and
a commercial electric vehicle steering system, comprising:
a recirculating ball steering unit, coupled to the commercial electric vehicle frame and comprising a rotatable output shaft configured to rotate around an output axis;
a track rod, comprising:
a first end coupled to the first tie rod;
a second end coupled to the second tie rod;
a pitman attachment, disposed between the first end and the second end; and
an idler attachment, disposed between the first end and the second end;
a pitman arm, coupled to the rotatable output shaft and the pitman attachment;
an idler arm, coupled to the idler attachment; and
a steering idler, comprising:
a steering idler ball joint comprising:
an idler ball stud, coupled to the commercial electric vehicle frame and comprising a steering idler ball; and
a stud shaft, the stud shaft coupled to the idler arm and configured to rotate around a stud axis, the stud axis disposed substantially laterally in line with the output axis;
a substantially cylindrical sidewall, enclosing at least a portion of the stud shaft; and
a bushing, coupled to the stud shaft and the substantially cylindrical sidewall, containing an outside diameter of the stud shaft, and configured to prevent angular rotation of the idler ball stud.
12 . The commercial electric vehicle of claim 11 , wherein the steering idler ball joint further comprises an idler ball socket, wherein the steering idler ball is disposed within the idler ball socket.
13 . The commercial electric vehicle of claim 12 , wherein the idler ball socket is disposed proximate the commercial electric vehicle frame.
14 . The commercial electric vehicle of claim 11 , wherein the idler arm is coupled to the idler attachment with an idler arm ball joint.
15 . The commercial electric vehicle of claim 14 , wherein a first distance between the output axis and the pitman attachment is substantially similar to a second distance between the stud axis and the idler attachment.
16 . The commercial electric vehicle of claim 15 , wherein the pitman arm is coupled to the pitman attachment with a pitman arm ball joint.
17 . The commercial electric vehicle of claim 16 , wherein the idler arm ball joint comprises:
an idler arm ball, disposed within an idler socket of the idler arm; and
an idler arm shaft, coupled to the idler attachment.
18 . The commercial electric vehicle of claim 17 , wherein the idler socket comprises a lip configured to allow less than 2 degrees of angular rotation for the idler arm ball joint.
19 . The commercial electric vehicle of claim 16 , wherein the pitman arm ball joint comprises:
a pitman arm ball, disposed within a pitman socket of the pitman arm; and
a pitman arm shaft, coupled to the pitman attachment.
20 . The commercial electric vehicle of claim 11 , wherein at least a portion of the stud shaft is non-tapered.