Steering column assembly

• US 3,877,319 A
• Filed: 11/19/1973
• Issued: 04/15/1975
• Est. Priority Date: 11/19/1973
• Status: Expired due to Term

• Current Assignee: Duane D. Cooper
• Original Assignee: Duane D. Cooper
• Inventors: Cooper, Duane D.
• Primary Examiner(s): Scott, Samuel
• Assistant Examiner(s): Chandler, Lance W.
• Application Number:
  US05/416,831
• Time in Patent Office: 512 Days
• Field of Search: 74/492,493 188/1C
• US Class Current: 74/492
• CPC Class Codes: B62D 1/192 Yieldable or collapsible columns

Abstract

A vehicle steering column assembly of the collapsible, energy absorbing type incorporating an improved shift tube construction, the initial collapse load of which is closely controllable, the shift tube including a pair of telescopically related and radially spaced tube members, a plurality of radially projecting lanced keys on one of the tube members, a corresponding plurality of open-ended slots on the other tube member receiving respective ones of the keys for coupling the tube members for unitary rotation, and a cylindrical sleeve bearing between the tube members for facilitating relative axial collapse therebetween. The closed end of each slot engages the corresponding one of the lanced keys to normally prevent relative collapse between the tube members but is operative under predetermined axial loading on the shift tube to radially deform the corresponding key out of the slot to permit relative axial collapse.

Claims

1. In a steering column assembly adapted for axial collapse in an energy absorbing mode in response to an axially directed force input exceeding a predetermined minimum magnitude, the combination compriSing, a first tube member rotatably disposed on said steering column assembly, a second tube member rotatably disposed on said steering column assembly in axial alignment with said first tube member and including an end portion disposed in radially spaced telescopic relationship with respect to a corresponding end portion on said first tube member, bearing means disposed in the space between said telescopically related end portions for facilitating relative axial collapse therebetween, means on one of said first and said second tube member end portions defining a plurality of receptacles, means in the other of said first and said second tube member end portions defining a corresponding plurality of radially deformable keys projecting into respective ones of said receptacles for coupling said first and said second tube members for unitary rotation, and means on said one of said first and said second tube member end portions defining a plurality of abutments engaging corresponding ones of said keys for preventing relative axial collapse between said first and said second tube members, each of said abutments being operative to effect radial deformation of the corresponding one of said keys out of said receptacles for permitting relative axial collapse between said first and said second tube members when said axially directed force input achieves said predetermined minimum magnitude.

2. In a steering column assembly adapted for axial collapse in an energy absorbing mode in response to an axially directed force input exceeding a predetermined minimum magnitude, the combination comprising, a first cylindrical tube member rotatably disposed on said steering column assembly, a second tube member rotatably disposed on said steering column assembly in axial alignment with said first tube member and including a cylindrical end portion disposed in radially spaced telescopic relationship with respect to a corresponding cylindrical end portion on said first tube member, a cylindrical bearing having an annular flange at one end, said bearing being disposed between said cylindrical end portions with said annular flange abutting and end surface of one of said first and said second tube members thereby to prevent relative axial movement between said bearing and said one tube member while facilitating relative axial collapse between said first and said second tube members, means on one of said first and said second tube member end portions defining a plurality of axially extending slots each having one open end and one closed end, and means on the other of said first and said second tube member end portions defining a corresponding plurality of radially deformable keys projecting into respective ones of said slots for coupling said first and said second tube members for unitary rotation, each of said slot-closed ends engaging a corresponding one of said keys for preventing relative axial collapse between said first and said second tube members and being operative to effect radial deformation of said corresponding key out of said slot for permitting relative axial collapse between said first and said second tube members when said axially directed force input achieves said predetermined minimum magnitude.

3. In a steering column assembly including an upper mast jacket section, a lower mast jacket section, and means interconnecting said first and said second mast jacket sections operative to normally maintain said first and said second mast jacket sections in fixed axial relationship and to permit relative axial telescopic collapse in an energy abosrbing mode in response to an axially directed force input exceeding a predetermined minimum magnitude, the combination comprising, a first cylindrical tube member having a substantially constant diameter rotatably disposed on said steering column assembly and adapted for bodily movement as a unit with said lower mast jacket section, a second cylindrical tube member having a diameter substantially less than said constant diameter rotatably disposed on saId steering column assembly and in axial alignment with said first tube member adapted for bodily movement as a unit with said upper mast jacket section, means on said second tube member defining a cylindrical end portion having a diameter intermediate the diameters of said first and said second tube members, said end portion being telescopically disposed within said lower mast jacket section and spaced radially therefrom, a cylindrical bearing having an annular flange at one end, said bearing being disposed between said end portion and said first tube member with said annular flange engaging an end surface of said first tube member thereby to prevent relative axial movement between said bearing and said first tube member while facilitating relative axial collapse between said first and said second tube members, means on said end section defining a plurality of angularly spaced and axially extending slots each having one open end and one closed end, and means on said first tube member defining a corresponding plurality of integral radially deformable keys each projecting radially inwardly into a respective one of said slots for coupling said first and said second tube members for unitary rotation, each of said slot-closed ends engaging a corresponding one of said keys for preventing relative axial collapse between said first and said second tube members and being operative to effect radial deformation of said corresponding key out of said slot for permitting relative axial collapse between said first and said second tube members when said axially directed force input achieves said predetermined minimum magnitude.