Patient transport apparatus with controlled auxiliary wheel speed

A patient transport apparatus moveable over a floor surface, the patient transport apparatus comprising:

• a support structure;
• an auxiliary wheel coupled to the support structure to influence motion of the patient transport apparatus over the floor surface;
• a auxiliary wheel drive system coupled to the auxiliary wheel to rotate the auxiliary wheel relative to the support structure;
• a throttle assembly including:
• an inner support defining a central axis,
• a handle body operatively attached to the inner support and configured to be gripped by a user,
• a throttle arranged for rotational movement about the central axis between a neutral throttle position and one or more operating throttle positions including one or more forward throttle positions and one or more backward throttle positions,
• an emitter configured to generate a magnetic field and being coupled to the throttle for concurrent movement therewith, and
• a detector operatively attached to the inner support and being responsive to predetermined changes in the magnetic field generated by the emitter to determine a relative position of the emitter as the throttle moves from the neutral throttle position to the one or more operating throttle positions;
• and
• a controller coupled to the auxiliary wheel drive system and the detector, with the controller configured to operate the auxiliary wheel drive system to rotate the auxiliary wheel in a forward direction when the detector determines movement of the emitter with the throttle from the neutral throttle position to the one or more forward throttle positions, and further configured to operate the auxiliary wheel drive system to rotate the auxiliary wheel in a backward direction when the detector determines movement of the emitter with the throttle from the neutral throttle position to the one or more backward throttle positions.