Energy absorbing device and safety steering column for a vehicle equipped with the device

Claim 2

An energy absorbing device operating by plastic deformation, comprising a first element defining an opening including a slot extending in a given path ,a second element in spaced relation to the first element ,projecting means on the second element disposed in the extension of said path beyond one end of the slot for penetration in the slot upon relative movement between the elements in a direction parallel to said path ,the width of the projecting meanS being greater than the width of the slot whereby said relative movement is accompanied by plastic deformation of the first element, spacer means for maintaining the two elements in spaced relation to each other and for guiding the two elements in said relative movement while allowing angular displacement between the two elements .

Claim 3

A device as claimed in claim 1, wherein the first element has a portion in the form of a flat plate, the slot being a throughway slot in the plate.

Claim 4

A device as claimed in claim 1, wherein said opening defines an aperture at said one end of the slot , which aperture opens into the slot and the projecting means extends into said aperture ,the guide means comprising the projecting means, an enlarged head on the projecting means in retaining engagement with the first element and spacer means combined with the projecting means and interposed between the first element and second element .

Claim 5

A device as claimed in claim 1, wherein the projecting means comprises a cylindrical member, the opening includes a first aperture opening into the slot and the second element has means defining a second aperture aligned with said first aperture and the cylindrical member extends through the apertures and is secured to the second element and has an enlarged head retaining the first element and a washer on the member is interposed between the first element and second element to maintain the two elements in spaced relation .

Claim 6

A safety steering column for a vehicle having a body, the steering column comprising a steering shaft, an energy absorbing device operating by plastic deformation and comprising a first element defining an opening including a slot extending in a given path ,a second element in spaced relation to the first element , projecting means on the second element disposed beyond one end of the slot for penetration in the slot upon relative movement between the elements in a direction parallel to said path ,the width of the projecting means being greater than the width of the slot whereby said relative movement is accompanied by plastic deformation of the first element, spacer means for maintaining the two elements in spaced relation to each other and for guiding the two elements in said relative movement while allowing angular displacement between the two elements ,one of the two elements being connected in a rigid manner to the body of the vehicle and the other element being connected to the steering shaft to move axially with the steering shaft .

Claim 7

A safety steering column for a vehicle having a body, the steering column comprising a steering shaft, an energy absorbing device operating by plastic deformation and comprising a first element defining an opening including a slot extending in a given path ,a second element in spaced relation to the first element , projecting means on the second element disposed beyond one end of the slot for penetration in the slot upon relative movement between the elements in a direction parallel to said path ,the width of the projecting means being greater than the width of the slot whereby said relative movement is accompanied by plastic deformation of the first element, spacer means for maintaining the two elements in spaced relation to each other and for guiding the two elements in said relative movement while allowing angular displacement between the two elements ,one of the two elements being connected in a rigid manner to the body of the vehicle and the other element being connected to the steering shaft to move axially with the steering shaft .

Claim 8

A steering column as claimed in claim 5, wherein the two elements are of sheet material and have a generally U-shaped section transverse to said path and one element is disposed inside the other and constitutes an inner element whereas the other element constitutes an outer element, the U-shaped section defining in each element a web portion and two flanges ,the flanges of one of the elements being free to deform transversely of said path .

Claim 9

A steering column as claimed in claim 6, wherein the flanges of the inner element have portions which extend outwardly ,the inner element being fixed to the body of the vehicle by said outwardly extending portions whereas the outer element is connected to the steering shaft of the vehicle by the web portion of the outer element .

Claim 10

A safety steering column structure for a vehicle which has a body, the steering column structure comprising a steering shaft and an energy absorbing device which comprises a first generally U-sectioned element, a second generally U-sectioned element, one element being disposed inside the other element in spaced relation to said other element and movable relative to said other element in a given direction transverse to said U-sections, spacer means interposed between the two elements to maintain the elements in spaced relation to each other in directions transverse to said given direction but allowing a relative movement between the elements in said given direction, the first element defining an elongate opening including a slot extending in a direction parallel to said given direction, projecting means carried by the second element and located beyond one end of the slot in a position for penetration in the slot upon said relative movement in said given direction, the width of the projecting means being greater than the width of the slot so as to widen the slot by plastic deformation of the first element and thereby absorb energy upon said relative movement, one of the elements being connected rigidly to said body and the other of the elements being connected to the steering shaft to move axially with the steering shaft upon movement of the shaft due to application of a predetermined force on the steering shaft.

Claim 11

A safety steering column structure for a vehicle which has a body, the steering column structure comprising a steering shaft and an energy absorbing device which comprises a first generally U-sectioned element, a second generally U-sectioned element, one element being disposed inside the other element in spaced relation to said other element and movable relative to said other element in a given direction transverse to said U-sections, spacer means interposed between the two elements to maintain the elements in spaced relation to each other in directions transverse to said given direction but allowing a relative movement between the elements in said given direction, the first element defining an elongate opening including a slot extending in a direction parallel to said given direction, projecting means carried by the second element and located beyond one end of the slot in a position for penetration in the slot upon said relative movement in said given direction, the width of the projecting means being greater than the width of the slot so as to widen the slot by plastic deformation of the first element and thereby absorb energy upon said relative movement, one of the elements being connected rigidly to said body and the other of the elements being connected to the steering shaft to move axially with the steering shaft upon movement of the shaft due to application of a predetermined force on the steering shaft.

Claim 12

A steering column as claimed in claim 8 ,comprising a ring of resiliently yieldable material, a bearing mounting the ring on the steering shaft, and screws extending through the ring ,the element connected to the steering shaft being connected to the steering shaft by said screws .

Claim 13

A steering column as claimed in claim 8 ,comprising elongated guiding elements extending in a direction substantially parallel to said path between the U-section elements, confronting offset portions in the two U-section elements engaging the guiding elements for guiding the elements in said path .

Claim 14

An energy absorbing device comprising a first element defining an opening including a slot which extends in a given path, a second element in spaced relation to the first element and movable relative to the first element in a direction parallel to said path, a projecting member carried by the second element and located in the extension of said path beyond one end of the slot for penetration in the slot upon relative movement between the two elements in a direction parallel to said path, the width of the projecting member being greater than the width of the slot whereby said relative movement is accompanied by plastic deformation of the first element, spacer means for maintaining the two elements in spaced relation to each other and for guiding the two elements in said relative movement while allowing angular displacement between the two elements,and shearable means for ordinarily holding the two elements assembled in a fixed relative position, the shearable means being capable of shearing when a force is exerted on one of the elements which is beyond a threshold value beyond which energy must be absorbed by the device.

Claim 15

An energy absorbing device comprising a first element defining an opening including a slot which extends in a given path, a second element in spaced relation to the first element and movable relative to the first element in a direction parallel to said path, a projecting member carried by the second element and located in the extension of said path beyond one end of the slot for penetration in the slot upon relative movement between the two elements in a direction parallel to said path, the width of the projecting member being greater than the width of the slot whereby said relative movement is accompanied by plastic deformation of the first element, spacer means for maintaining the two elements in spaced relation to each other and for guiding the two elements in said relative movement while allowing angular displacement between the two elements,and shearable means for ordinarily holding the two elements assembled in a fixed relative position, the shearable means being capable of shearing when a force is exerted on one of the elements which is beyond a threshold value beyond which energy must be absorbed by the device.

Claim 16

A device ao claimed in claim 11, wherein the first element has a first wall portion defining the opening and a second wall portion at an angle to the first wall portion and extending in a direction parallel to said path and the second element has a wall portion extending in a direction parallel to said path, the spacer means being interposed between and engaging said second wall portion and the wall portion of the second element.