Self-operating extension flush bolt

Claim 2

In a self-operating flush bolt mechanism for latching the inactive one of a pair of swinging doors, which is operated to latch the door, once the latter is closed, by swinging movement of the other or inactive door to the closed position, a support adapted to be mounted on the inactive door, an extensible and retractable shaft rotatable in said support and including a latch bolt at one end thereof, bolt-operating means comprising a cam for engagement by the active door mounted for swinging movement on said support, gear means driven by the cam to rotate said shaft, and means intermediate the support and the shaft which upon rotation of the shaft in one direction effects positive axial movement of the shaft and bolt to extend the latter to latched position.

Claim 3

A self-operating flush bolt mechanism as defined in claim 1 wherein said bolt-operating means comprises spring means operative to retract the bolt to unlatched position on disengagement of said cam when the active door is opened.

Claim 4

A self-operating flush bolt mechanism as defined in claim 1, wherein said cam has a toothed portion and said gear means comprises a gear member fixed to said shaft so as to be axially movable therewith and meshing with said toothed portion of the cam.

Claim 5

A self-operating flush bolt mechanism as defined in claim 1 wherein said bolt-operating means comprises spring means operative to retract the bolt to unlatched position on disengagement of said cam when the active door is opened, said cam having a toothed portion, said gear means comprising a gear member fixed to said shaft so as to be axially movable therewith and meshing with said toothed portion of the cam, said cam being mounted for nontranslatory movement.

Claim 6

A self-operating flush bolt mechanism as defined in claim 1 wherein said bolt-operating means comprises spring means operative to retract the bolt to the unlatched position on disengagement of said cam when the active door is opened, said means intermediate the shaft and the support for effecting axial movement of the shaft in a bolt-latching direction comprising helical cam track means on the shaft engaged by pin means on the support.

Claim 7

A self-operating flush bolt mechanism as defined in claim 1 wherein a guide element in provided for the bolt adapted to be fixed to the inactive door and in which the bolt is slidable, and a strike is provided having an element for reception of the bolt and adapted to be fixed to the doorframe, and wherein a bimetallic member is provided having a movable arm normally disposed longitudinally of the bolt, one end of which is in fixed relation to the bolt and having a free end extensible with the bolt past one of said elements and which on being subjected to high environmental temperatures bends outwardly from the bolt to provide an abutment engageable with the last-mentioned one of said elements to prevent retraction of the bolt.

Claim 8

A self-operating flush bolt mechanism as defined in claim 1 wherein said means intermediate the shaft and the support for effecting axial movement of the shaft in a bolt-latching direction comprises coacting cam means on the shaft and the support.

Claim 9

A self-operating flush bolt mechanism as defined in claim 3 wherein said cam is mounted for nontranslatory movement.

Claim 10

A self-operating flush bolt mechanism as defined in claim 7 wherein said coacting cam means on the shaft and the support comprises helical track means on the shaft engaged by pin means on the support.

Claim 11

In a bolt mechanism having a strike, a support, a movable bolt in the support extensible into the strike, the improvement comprising a stationary guide element for the bolt in which element the bolt is slidable, the strike having a fixed element thereon, and a bimetallic member having a movable arm normally disposed longitudinally of the bolt, one end of which is in fixed relation to the bolt and having a free end extensible with the bolt past one of said elements and which on being subjected to high environmental temperatures bends outwardly from the bolt to provide an abutment engageable with the last-mentioned one of said elements to prevent retraction of the bolt.

Claim 12

In a bolt mechanism having a strike, a support, a movable bolt in the support extensible into the strike, the improvement comprising a stationary guide element for the bolt in which element the bolt is slidable, the strike having a fixed element thereon, and a bimetallic member having a movable arm normally disposed longitudinally of the bolt, one end of which is in fixed relation to the bolt and having a free end extensible with the bolt past one of said elements and which on being subjected to high environmental temperatures bends outwardly from the bolt to provide an abutment engageable with the last-mentioned one of said elements to prevent retraction of the bolt.

Claim 13

For use in conjunction with a pair of swinging doors, a bolt mechanism comprising a support member having a surface adapted to be mounted essentially flush with the free edge of one of a pair of the doors, shaft support means extending from said support member, a shaft slidable carried by said support means and including a latch bolt at one end thereof, a cam pivotally carried by said support member and extending beyond said face thereof and adapted to be engaged by the other of the swinging doors, gear means, said cam arranged to engage and rotate said gear means, and means on said shaft responsive to rotation of said gear means for imparting linear movement to said shaft.

Claim 14

For use in conjunction with a pair of swinging doors, a bolt mechanism comprising a support member having a surface adapted to be mounted essentially flush with the free edge of one of a pair of the doors, shaft support means extending from said support member, a shaft slidable carried by said support means and including a latch bolt at one end thereof, a cam pivotally carried by said support member and extending beyond said face thereof and adapted to be engaged by the other of the swinging doors, gear means, said cam arranged to engage and rotate said gear means, and means on said shaft responsive to rotation of said gear means for imparting linear movement to said shaft.

Claim 15

The mechanism of claim 11 wherein said shaft has said gear means carried thereon and said cam means has teeth thereon engaging said gear means,

Claim 16

The mechanism of claim 11 further including a spring acting on said shaft to return said shaft when said cam is disengaged by said other of the doors.

Claim 17

The mechanism of claim 11 wherein said means for imparting linear motion comprises a helical groove on said shaft, a pin carried by said support member extending into said groove.

Claim 18

For use in conjunction with a pair of swinging doors, a bolt mechanism comprising a support member having a surface adapted to be mounted essentially flush with the free edge of one of a pair of swinging doors, shaft support means extending from said support member on the side thereof opposite said surface, a shaft slidably carried by said support means and including a latch bolt at one end thereof adapted to be extended beyond a horizontal edge of the door, spring means normally biasing said shaft to a retracted position, a cam pivotally carried by said support member and extending beyond the face thereof and adapted to be engaged by the other of the swinging doors, gear means, said cam arranged to engage and rotate said gear means and impart linear movement to said shaft to move said latch bolt behind the horizontal edge against the bias of said spring.

Claim 19

For use in conjunction with a pair of swinging doors, a bolt mechanism comprising a support member having a surface adapted to be mounted essentially flush with the free edge of one of a pair of swinging doors, shaft support means extending from said support member on the side thereof opposite said surface, a shaft slidably carried by said support means and including a latch bolt at one end thereof adapted to be extended beyond a horizontal edge of the door, spring means normally biasing said shaft to a retracted position, a cam pivotally carried by said support member and extending beyond the face thereof and adapted to be engaged by the other of the swinging doors, gear means, said cam arranged to engage and rotate said gear means and impart linear movement to said shaft to move said latch bolt behind the horizontal edge against the bias of said spring.