Vehicle seat track apparatus

A split-frame power seat track mechanism for supporting and positioning a seat assembly including a seat cushion and a seat back within a motor vehicle, said mechanism comprising:

• laterally spaced rail members fixed to said vehicle;
• a carriage carried by said rail members for controlled longitudianl displacement, said seat cushion interconnected with said carriage through a front, lost motion pivot connection disposed intermediate a front edge of said seat cushion and a front underlying portion of said carriage and a rear fixed pivot connection disposed intermediate a rear edge of said seat cushion and a rear underlying portion of said carriage;
• first drive means operative to selectively longitudinally position said carriage in response to a first operator input;
• second drive means engaging said front pivot connection operative to selectively vertically position said front edge of said seat cushion in response to a second operator input;
• and
• third drive means engaging said rear pivot connection operative to selectively vertically displace said rear edge of said seat cushion in response to a third operator input, between fully raised and lowered end limits of travel and to simultaneously longitudinally displace said seat cushion with respect to said carriage between a fully retracted and extended end limits of travel.

In combination:

• a seat assembly including a seat cushion and a seat back;
• and
• a split-frame power seat track mechanism for supporting and positioning said seat assembly within a motor vehicle, said mechanism comprising;
• laterally spaced rail members fixed to said vehicle,
• a carriage carried by said rail members for controlled longitudinal displacement, said seat cushion interconnected with said carriage through a front, lost motion pivot connection disposed intermediate a front edge of said seat cushion and a front underlying portion of said carriage and a rear fixed pivot connection disposed intermediate a rear edge of said seat cushion and a rear underlying portion of said carriage,
• first drive means operative to selectively longitudinally position said carriage in response to a first operator input,
• second drive means engaging said front pivot connection operative to selectively vertically position said front edge of said seat cushion in response to a second operator input, and
• third drive means engaging said rear pivot connection operative to selectively vertically displace said rear edge of said seat cushion in response to a third operator input between fully raised and lowered end limits of travel and to simultaneously langitudinally displace said seat cushion with respect to said carriage between a fully retracted and extended end limits of travel.