Safety cabinet with sequential door-closing system

1. A safety cabinet comprising:

an enclosure defining an opening;

a first door and a second door, each door being rotatably mounted to the enclosure and moveable over a range of travel between an open position and a closed position, the first and second doors adapted to cover the opening of the enclosure when in the closed position;

a sequential door-closing system adapted to sequentially close the first and second doors such that when the first and second doors move in respective first and second door closing paths from the open position to the closed position, the first door is in the closed position before the second door, the sequential door-closing system including a stop member, a connecting assembly, a trigger member, and a trigger biasing mechanism, wherein:

the stop member is rotatably mounted to the enclosure and moveable over a range of travel between a stop position, in which at least a portion of the stop member is disposed in the second door closing path of the second door, and a retracted position, in which the stop member is displaced from the second door closing path, the stop member being biased to the stop position,

the connecting assembly is in interconnecting relationship with the stop member and the trigger member, the connecting assembly adapted to contactingly engage the trigger member at a locking interface to selectively retain the stop member in the stop position,

the trigger member is rotatably mounted to the enclosure and moveable over a range of travel between a locked position, in which the trigger member and the connecting assembly are in interlocking relationship at the locking interface to prevent rotational movement of the stop member from the stop position and in which at least a portion of the trigger member is disposed in the first door closing path of the first door, and a retracted position, in which the trigger member is displaced from the first door closing path, and the trigger member being biased to the locked position,

wherein the connecting assembly includes a cam with a first end and a second end, the cam pivotally mounted to the enclosure, the first end of the cam being engaged with the trigger member when the trigger member is in the locked position so as to prevent the cam from rotating, and a crosslink with a first end and a second end, the first end of the crosslink being pivotally connected to the stop member, and the second end of the crosslink being pivotally connected to the second end of the cam,

wherein the first end of the cam and the trigger member define the locking interface therebetween when the trigger member is in the locked position, the locking interface configured to prevent the cam from rotating in a retracting direction, and

the trigger biasing mechanism is adapted to bias the trigger member to the locked position, the trigger biasing mechanism comprising a spring connected at one end to the trigger member and at the other end to both the second end of the cam and the second end of the crosslink; and

wherein, as the second door moves over the second door closing path from the open position to the closed position, the stop member is adapted to selectively stop the second door at a trailing door position along the second door closing path and to prevent the second door from moving to the closed position;

wherein the trigger member, when in the locked position, is adapted to contact the first door at a leading door position along the first door closing path, the leading door position being closer to the closed position of the first door than the trailing door position is to the closed position of the second door; and

wherein, as the first door moves over the first door closing path from the open position to the closed position, the first door contacts the trigger member at the leading door position such that continued movement of the first door to the closed position causes the trigger member to rotate in a release direction away from the locked position to the retracted position to thereby disengage the trigger member from the connecting assembly such that the trigger member is no longer in contacting relationship with the cam at the locking interface, thereby allowing the stop member to rotate away from the stop position to the retracted position to allow the second door to move to the closed position after the first door is in the closed position.

2. The safety cabinet of claim 1 , wherein the stop member includes a distal end comprising a first rotating wheel, and the trigger member includes a distal end comprising a second rotating wheel, the first and second wheels configured to rotatingly engage the first and second doors, respectively, to permit relative movement therebetween when the first and second doors move from the leading door intermediate position to the closed position and the trailing door intermediate position to the closed position, respectively.

3. The safety cabinet of claim 1 , wherein the first door has an inner sealing flange, and the second door has an outer sealing flange, the flanges configured so as to be in overlapping relationship with each other when the first and second doors are in the closed position.

4. The safety cabinet of claim 1 , wherein the connecting assembly of the sequential-door closing system further includes a cam stop member adapted to limit rotation of the cam in an extending direction, the extending direction being in opposing relationship to the retracting direction.

5. The safety cabinet of claim 1 , wherein the sequential-door closing system further includes a stop biasing mechanism adapted to bias the stop to the stop position.

6. The safety cabinet of claim 5 , wherein the stop biasing mechanism comprises a spring attached at one end to the enclosure and at the other end to the stop member and the first end of the crosslink.

7. The safety cabinet of claim 1 , further comprising:

first and second actuators adapted to urge the first and second doors, respectively, to the closed position.

8. The safety cabinet of claim 7 , further comprising:

first and second door retention mechanisms adapted to selectively retain the first and second doors, respectively, in the open position.

9. The safety cabinet of claim 8 , wherein the first and second door retention mechanisms each comprises a fusible link respectively connecting the first door and the enclosure and the second door and the enclosure, the fusible links being configured to fuse when the ambient temperature reaches a predetermined temperature, thereby allowing the first and second doors to respectively move to the closed position.

10. The safety cabinet of claim 1 , further comprising:

first and second door retention mechanisms adapted to selectively retain the first and second doors, respectively, in the open position.

11. A sequential door-closing system configured to sequentially close first and second doors rotatably mounted to an enclosure, the first and second doors each movable over a range of travel between an open position and a closed position, the sequential door-closing system comprising a stop member, a connecting assembly, a trigger member, and a trigger biasing mechanism, wherein:

the stop member is adapted to be rotatably mounted to the enclosure and moveable over a range of travel between a stop position and a retracted position, the stop member being biased to the stop position;

the connecting assembly is in interconnecting relationship with the stop member and the trigger member, the connecting assembly adapted to contactingly engage the trigger member at a locking interface to selectively retain the stop member in the stop position; and

the trigger member adapted to be rotatably mounted to the enclosure and moveable over a range of travel between a locked position, in which the trigger member and the connecting assembly are in interlocking relationship at the locking interface to prevent rotational movement of the stop member from the stop position, and a retracted position, and the trigger member being biased to the locked position via the trigger biasing mechanism;

wherein the connecting assembly includes a cam with a first end and a second end, the cam pivotally mounted to the enclosure, the first end of the cam being engaged with the trigger member when the trigger member is in the locked position so as to prevent the cam from rotating, and a crosslink with a first end and a second end, the first end of the crosslink being pivotally connected to the stop member, and the second end of the crosslink being pivotally connected to the second end of the cam;

wherein the first end of the cam and the trigger member define the locking interface therebetween when the trigger member is in the locked position, the locking interface configured to prevent the cam from rotating in a retracting direction;

wherein moving the trigger member from the locked position in a release direction toward the retracted position disengages the trigger member from the connecting assembly such that the trigger member is no longer in contacting relationship with the cam at the locking interface and such that the stop member is rotatable from the stop position to the retracted position; and

wherein the trigger biasing mechanism comprising a spring connected at one end to the trigger member and at the other end to both the second end of the cam and the second end of the crosslink.

12. The sequential door-closing system of claim 11 , wherein the stop member includes a distal end, and the trigger member includes a distal end, the distal end of the trigger in offset outward relationship to the distal end of the stop member when the trigger member is in the locked position and the stop member is in the stop position.

13. The sequential door-closing system of claim 11 , wherein the stop member includes a distal end comprising a first rotating wheel, and the trigger member includes a distal end comprising a second rotating wheel.

14. The sequential door-closing system of claim 11 , wherein the connecting assembly includes a cam stop member adapted to limit rotation of the cam in an extending direction, the extending direction being in opposing relationship to the retracting direction.

15. The sequential door-closing system of claim 11 , further comprising:

a stop biasing mechanism, the stop biasing mechanism being adapted to bias the stop to the stop position.

16. The sequential door-closing system of claim 15 , wherein the stop biasing mechanism comprises a spring attached at one end to the stop member and the first end of the crosslink.