Apparatus for controlling and protecting a vehicle seat suspension

• US 5,169,113 A
• Filed: 11/07/1990
• Issued: 12/08/1992
• Est. Priority Date: 11/07/1990
• Status: Expired due to Term

• Current Assignee: Sears Manufacturing Co.
• Original Assignee: Sears Manufacturing Co.
• Inventors: Brodersen, Cole T.
• Primary Examiner(s): Friedman, Carl D.
• Assistant Examiner(s): BERGER, DEREK JOEL
• Application Number:
  US07/610,082
• Time in Patent Office: 762 Days
• Field of Search: 248/550, 248/631, 248/584, 248/421, 248/157, 248/161, 248/563, 248/423, 248/188.2, 297/339, 297/347, 297/345
• US Class Current: 248/550
• CPC Class Codes: B60N 2/501 actively controlled suspension, e.g. electronic control
• CPC Class Codes: B60N 2/505 Adjustable suspension including height adjustment
• CPC Class Codes: B60N 2/508 Scissors-like structure
• CPC Class Codes: B60N 2/525 using gas

Abstract

A device is disclosed that overrides the manual controls for filling and emptying an air suspension spring, so that the spring is not over-filled or under-filled. The device also includes a mechanism for limiting the rise of the seat suspension when the driver exits the seat. The invention has a latch bar that slides through two pieces of lubricating plastic. A ramped section of the latch bar contacts one of two switches that prevents the adjustment of a seat suspension below a minimum safe ride position or prevents adjustment above a maximum safe position. The latch bar also includes notches that are engageable with a latch pawl that is operated by a solenoid. When an operator leaves the seat, the solenoid is energized and drives the latch pawl into a notch in the latch bar. An electronic switch also enables the deenergizing of the solenoid, yet the latch pawl locks the latch bar so that the air spring does not cause a substantial rise in the seat suspension.

Claims

1. A device for limiting the vertical displacement of a seat suspension when the load on the suspension is removed, comprising:

means for sensing the load removal;

means for locking the unloaded suspension in a fixed vertical position proximate the loaded position responsive to said sensing means, said locking means including a solenoid for engaging a latch; and

means for unlocking the suspension.

2. The apparatus of claim 1 further comprising a means for disconnecting power to said solenoid.

3. The apparatus of claim 1 wherein said unlocking means comprises a spring for disengaging said latch.

4. The apparatus of claim 1 wherein said sensing means is an electronic switch.

5. A vehicle suspension apparatus for protecting an air spring and for limiting the vertical displacement of a vehicle seat supported by the air spring when the seat is vacated by an occupant, comprising:

a movable member responsive to the vertical motion of the vehicle seat and including a plurality of notches;

means for varying the pressure in the air spring;

means for enabling and disabling said varying means responsive to engagement or disengagement with said movable member;

means for substantially instantly sensing the occupant vacating the seat;

means for substantially instantly locking the suspension when the seat is vacated at substantially the same position as before the seat was vacated, said locking means being responsive to said sensing means and adapted to engage one of said notches of said movable member; and

means for unlocking the suspension, including means for disengaging said locking means from said notches of said movable member.

6. The device of claim 5 further comprising a bearing means to facilitate the movement of said movable member.

7. The device of claim 5 wherein said unlocking means provides a biasing force in a direction away from said notches.

8. The apparatus of claim 5 wherein said actuating means comprises a first switch for limiting the gas pressure to a minimum amount and a second switch for limiting the gas pressure to a maximum amount.

9. The apparatus of claim 5, wherein said locking means includes a solenoid for engaging a latch.

10. A device for limiting the vertical displacement of a vehicle seat air spring suspension when the load on the suspension is removed and for protecting the air spring, comprising:

a movable member responsive to the vertical motion of the seat;

engageable latch means for limiting upward movement of the seat when the load on the suspension is removed, said latch means normally being disengaged while the vehicle seat is occupied and, said latch means including notches on said movable member;

electrical means for sensing when the vehicle seat is not loading the seat suspension;

latch actuating means, responsive to said electrical sensing means, for moving said latch means into engagement to limit upward movement of the seat suspension so that it remains in substantially the same position as when loaded;

electrical means for deactivating said latch actuating means while said latch means remains engaged to limit upward movement of the seat suspension;

biasing means for disengaging said latch means;

means for varying the pressure in the air spring; and

means for enabling and disabling said varying means responsive to engagement or disengagement with said movable member.

11. A device for limiting the vertical displacement of a seat suspension when the load on the suspension is removed and for protecting an air spring, comprising:

means for substantially instantly sensing the load removal;

locking means, responsive to said sensing means, for substantially instantly fixing the suspension in a position vertically proximate to the position of the suspension prior to removal of the load;

means for unlocking the suspension;

means for adding and releasing compressed air to the air spring;

first and second electrical switches; and

a slidable member positionally engageable with said first and second electrical switches, whereby in one position of said slidable member air can be added or released, in a second position air can be added but not released, and in a third position air can be released but not added.