Control knob with safety feature

An apparatus comprising

• a first hand-operated control mounted on a hub for axial movement between a first position and a second position relative to the hub,
• a mechanism that axially rigidly couples the control to the hub in the first position unless a force greater than a threshold is applied to the control, and
• a second hand-operated control that surrounds the first control,
• in which in the first axial position a first portion of the first control extends beyond a plane defined by a surface of the second control, and
• in the second axial position the first portion of the first control does not extend beyond the plane.

An apparatus comprising

• a first hand-operated control mounted on a hub for axial movement between a first position and a second position relative to the hub, and comprising a first portion having a hardness greater than about 50 shore A and a second portion having a hardness less than about 50 shore A,
• a mechanism that axially rigidly couples the control to the hub in the first position unless a force greater than about 57 newtons is applied to the control, and
• a second hand-operated control comprising a ring concentric with the first control,
• in which in the first axial position the first portion of the first control extends beyond a plane defined by a surface of the second control,
• in the second axial position the first portion of the first control does not extend beyond the plane, and
• the second portion of the first control extends beyond the plane in both the first and second axial positions.

A user interface device for use in automobiles, the device comprising

• a control knob for controlling at least one function of the device and mounted on a hub for axial movement between a first position and a second position relative to the hub,
• a mechanism that axially rigidly couples the control knob to the hub in the first position unless a force greater than a threshold is applied to the control knob, and
• a hand-operated control ring for controlling at least one second function of the device and that surrounds the control knob;
• in which in the first axial position a first portion of the control knob extends beyond a plane defined by a surface of the control ring, and
• in the second axial position the first portion of the control knob does not extend beyond the plane.