US 3582122 A
Description (OCR text may contain errors)
United States Patent  Inventors John R. Foster;
Larry R. Hunt, both of Indianapolis, Ind. 21 Appl. No. 856,788  Filed Sept. 10,1969  Patented June I, 1971  Assignee Von Duprin Inc.
 AUTOMATIC FLUSH BOLT I0 Claims, 8 Drawing Figs.
 U.S. CI 292/335, 292/21, 292/92, 292/Dig.21  Int. Cl E051) 13/20, EOSc 15/02,, EOSc 19/02  Field of Search...., 292/335, 92, DIG 21, 332, 336, 34, 36, 32, 153; 70/92 [56-] References Cited UNITED STATES PATENTS 423,109 3/1890 Austermuhl 292/153 1,338,713 5/1920 TOney 292/335 1,391,005 9/1921 Palmer 292/92 1,677,271 7/1928 Carroll 292/21X 3,455,591 7/1969 Powers 292/335 Primary Examinerlan A. Calvert Assistant Examiner-Edward J. McCarthy Attorney-Hood, Gust, Irish, Lundy & Coffey ABSTRACT: Automatic flush bolt latch means for one of a mating pair of doors, so constructed and arranged that, when both doors are closed, said one door is affirmatively locked, that when the other door is even slightly opened said one door will remain latched but with its latch means readily retractable by the application of gentle opening force to said one door, and that said latch means, when once retracted, will remain so until both doors again assume closed positions, no matter which door closes first, whereupon said one door will again be affirmatively locked for so long as said other door remains closed.
PATENiTEDY N Han 3,582,122
SHEET 1 BF 2 T Y L I :3
C I b y E as 30 '5 5-23 will: :-24 32 l|| JY//4I 2 INVENTORS JOHN R. FOSTER o '2 BY LARRY R. HUNT F13 ywmgyw aw ATTORNEYS 0 6 s K m 1 RT 6 A M R w 9 Q fifl MEN 9 J d 8 2 m a 2 mm. 7 .R 1| R 2 L? 0/E L '|l|l Nm M M 2 m. HR WV we 5 mm m, j r w my SHEET 2 BF 2 PATENTED N 1 9? ATTORNEYS AUTOMATIC FLUSH BOLT The present invention relates to an automatic flush bolt and actuator means therefor. It is not unusual in public buildings such as schools and the like to provide portals closed by a pair of mating doors hinged at their respectively remote edges to the opposite jambs of the doorway and so arranged that, when the doors are in closed positions, their free edges substantially meet. Both of such doors must desirably be latched when in closed positions but be freely openable at all times in response to even gentle pressure impressed against their inner surfaces; but in many such installations it is desirable that one only of the two mating doors shall be utilize for normal traffic. In such installations, then, the door which is selected for handling normal traffic may be provided with latch means engageable with suitable keeper means, with a panic bar latch retractor on its inner surface and with suitable hardware such as a latchretracting thumb piece and a pull handle on its outer surface. The door which is to be normally inactive, on the other hand, is not provided with either a panic bar or external latch-actuating mechanism, but instead is provided with latch-retracting means accessible at its free edge and therefore manipulatable only when the active door is open. Such an arrangement is illustrated in FIGS. I4 to 16 of the US. Pat. to .l. R. Foster No. 3,l49,864 issued Sept. 22, 1964.
Such an arrangement, however, is unacceptable in some situations for the reason that the latch mechanism for the inactive door must be manually manipulated in order to release the door, so that the inactive door is not completely safe under panic conditions.
The primary'object of the present invention, then, is to provide latch mechanism for the inactive door of such a pair, the mechanism being of such character that, when both doors are closed, the inactive door will be affirmatively locked, when the active door is even slightly opened, the inactive door will respond freely to opening pressure exerted upon its inner surface, whereby its latch mechanism will be retracted, said latch mechanism will remain in retracted condition, when once retracted, until both doors have returned to closed positions, and said latch mechanism will be returned to affirmatively locking condition automatically when both doors do return to closed position, regardless of the sequence in which said doors so return to closed positions.
Further objects of the invention will appear as the description proceeds.
To the accomplishment of the above and related objects, our invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that change may be made in the specific construction illustrated and described, so long as the scope of the appended claims is not violated.
FIG. I is a perspective view of a doorway with mating doors of the character above described, the active door being shown ajar and the inactive door being shown equipped with latch mechanism according to the present invention.
FIG. 2 is any enlarged, fragmentary view of the upper, distal edge portion of the inactive door, with said door ajar;
FIG. 3 is avertical section through the upper, distal edge region of the inactive door, drawn to a further enlarged scale and illustrating our novel latch and actuator means;
FIG. 4 is a fragmentary section taken substantially on the line 4-4 of FIG. 3;
FIG. 5 is a view similar to the lower portion of FIG. 3 but showing the parts of the latch actuator mechanism in the positions which they will assume immediately upon opening of the active door;
FIG. 6 is a view similar to FIG. 3 showing the parts in the positions which they will assume during opening of the inactive door;
FIG. 7 is a fragmentary section taken substantially on the line 77 of FIG. 6; and
FIG. 8 is a rear elevation of the latch actuator mechanism taken substantially on the plane indicated by the line 8-8 of FIG. 5.
Referring more particularly to the drawings, it will be seen that we have illustrated in FIG. I a doorway, indicated generally by the reference numeral 10, and defined by a lintel II, a sill 12 (which may be merely a floor) and opposed, upright jambs I3 and 14. In the illustrated embodiment, a door 15 is hinged at its proximal edge to the jamb l3 and is provided near its upper, distal corner, with latch mechanism 16 which may be conventional for engagement with keeper means I7 set into lintel 11. Preferably, said door 15 will likewise be provided with latch mechanism at its lower, distal corner for cooperation with keeper means 18 set into the sill or floor 12. A panic bar I9 is supported from the inner surface of the door 15 for retracting the latch mechanism 16 and the corresponding latch mechanism at the lower end of the door. All of this may be conventional and in the assembly, the door 15 will be the active door and will be provided externally with suitable hardware (not shown ).v
A mating door 20 is hinged at its proximal edge to the jamb I4, and it will be understood that the two doors are so proportioned and designed that, when they are both in closed positions, their distal edges will substantially meet, whereby the doorway 10 is fully closed.
In the illustrated embodiment of the invention, it has been assumed that the doors I5 and 20 will be hollow metal doors of well-known construction. Automatic flush bolt latch mechanism, indicated generally by the reference numeral 21, is set into the upper portion of the distal edge 22 of the door 20. As is most clearly illustrated in FIG. 3, said door edge 22 is formed with a suitable opening 23 into which is set a flush plate 24 secured in place by any suitable means such as the machine screws illustrated. A catch plate 25 is suitably secured to the upper end of the door and is provided with an opening 26 therethrough for the passage of a latch bolt 27. Keeper means 28 is set into the lintel 11 for the reception of the latch bolt 27 when the latter is projected.
An actuator rod 29 fixedly carries the latchbolt 27 and is threaded as at 30 near its lower end for the reception of a sleeve 31 formed at its upper end with a stop collar which con stitutes an abutment for a coiled spring 32. The flush plate 24 is formed with an inwardly projecting boss 33 having a vertical bore 34 in which the lower portion of the sleeve 31 is guidingly received. Said boss is formed with a downwardly opening slot 35 for the reception of a pin 36 which traverses the sleeve 31 and secures thereto a ratchet member 65 formed to provide a downwardly facing shoulder 37 and inwardly projecting teeth 38 for a purpose which will appear. It will be apparent that the spring 32 yieldably biases the rod 29 and its associated parts toward projection of the latchbolt 27 and that the pin 36, in cooperation with the slot 35, limits the maximum degree of projection of the latchbolt.
Blocker means 39 is mounted for oscillation upon the flush plate 24 by means of a pivot 40 and is biased toward its position illustrated in FIG. 3 by means of a spring 41. As shown, said blocker means may be a stamping of generally U-shaped cross section and provided with opposite, laterally outwardly extending ears 63 (FIG. 8). It will be apparent that, when the blocker means 39 underlies the shoulder 37 in the relationship illustrated in FIG. 3, the actuator rod 29 and the latchbolt 27 carried thereby will be affirmatively locked in projected position whereby, if the bolt 27 is engaged in the keeper 28, the door 20 will be affirmatively locked against opening.
Pivotally supported upon a pin 42 mounted upon the flush plate 24 is a trigger 43 having an outwardly extending nose portion 44. As illustrated, the trigger 43 may be a stamping of generally U-shaped cross section, the nose portion 44 being formed upon the separated wings of said trigger and said wings being so spaced that the nose portion 44 of the trigger 43 may straddle the blocker means 39 to register cooperatively with the ears 63 of said blocker means. A spring 45 engages the lower end of the trigger 43 to bias said trigger in a clockwise direction as viewed in FIGS. 3, 5 and 6. The springs 41 and 45 I will hold the trigger 43 in the position of FIGS. 5 and 6 whereby said trigger will hold the blocker means 39 out of the path of the shoulder 37. A catch pin 46 spans the wings of the trigger 43 adjacent the distal end thereof and is so arranged that, when said trigger is in the position of FIGS. 5 and 6, downward movement of the rod 29 and its associated parts will move the teeth 38 into cooperative engagement with said catch pin 46. It will be apparent that the teeth 38 are so designed that, as the ratchet 65 moves downwardly, said teeth will click past the pin 46, rocking the trigger 43 but that, once a tooth is engaged with the catch pin 46, the rod 29 and its associated parts will be affirmatively held against upward movement under the influence of the spring 32.
Intermediate its ends, the trigger 43 fixedly carries a forwardly extending abutment finger 47 which cooperatively engages the proximal end of a trigger bolt 48. Referring particu larly to FIGS. 2 and 3, it will be seen that the trigger bolt 48 is guidingly mounted within an opening 49 in the flush plate 24. Said trigger bolt is substantially triangular in plan and, near its proximal comers, carries upwardly and downwardly projecting studs 50 which are adapted, as said bolt is moved from its position of FIG. 3 to its position of FIG. 5, to enter outwardly closed pockets 51 formed in the flush plate 24. The lateral surfaces of the bolt 48 are oppositely cammed, as at 52 (FIG. 2) and it will be seen that, when the bolt is in the position of FIG. 5, it may be laterally rocked in either direction about one or the other of the pairs of studs 50, or that it can be moved directly inwardly until it reaches a condition substantially as illustrated in FIG. 3. In any such case, it will be clear that movement of the bolt 48 until its distal portion is substantially flush with the plate 24 will act upon the abutment element 47 to rock the trigger 43 in a counter clockwise direction against the tendency of the spring 45. Quite obviously, as the trigger 43 moves in a counter clockwise direction, its catch pin 46 will be disengaged from the teeth 38 of the ratchet 65 and said trigger will release the blocker means 39 for movement in a counter clockwise direction under the influence of the spring 41.
Referring, now, more particularly to FIGS. 2, 4, 6 and 7, it will be seen that the latchbolt 27 is formed with a slot 53 opening through one lateral surface of said bolt and through the distal end thereof. A trip ratchet 54 is mounted upon a pivot 55 traversing said slot 53 near the proximal end thereof for movement between a fully nested position as illustrated in FIG. 4 and a laterally projecting position as illustrated in FIG. 7, under the influence of a spring 61. Said trip ratchet is formed in its distal region with a plurality of teeth 56 adapted, when said'trip ratchet is in its projected position, for cooperative engagement with the catch plate 25. At its distal end, the trip ratchet is formed with an elongated toe 57 for a purpose which will appear.
The outer, distal comer of the latchbolt 27 is formed to provide a cam surface 58 adapted to cooperate with a cam surface 59 on the keeper 28, the cam angle being such that, under the influence of door-opening pressure, the door will freely swing toward open position while the surfaces 58 and 59 cooperate to force the latchbolt 27 toward retracted position, It will be obvious, of course, that if the blocker means 39 is in the position illustrated in FIG. 3, such camming action cannot move the latch bolt, the rod 29 and the associated parts downwardly, and therefore the door will be affirmatively locked against opening. If, however, at this time the blocker means 39 is in the position of FIGS. 5 and 6, the rod 29 and its associated parts will be moved downwardly. As the toe 57 clears the keeper 28, the spring 61 will move the trip ratchet in a counterclockwise direction to engage one of the teeth 56 with the catch plate 25. This, of course, provides retaining means for the latchbolt and its associated parts, whereby the latchbolt will be held in fully retracted position even if the trigger bolt 48 should be accidentally or mischievously moved to disengage the catch pin 46 from the teeth 38. A stop pin 62 preferably spans the slot 53 to limit the degree of counterclockwise movement of the trip ratchet 54.
As is suggested in FIG. I, the door 20 will preferably be provided with a second flush bolt latch mechanism, indicated generally by the reference numeral 64, near its bottom distal comer for cooperation with keeper means similar to the keeper 18. Since the mechanism 64 may be identical with the mechanism 21, but simply arranged upon the door in an inverted position relative to the mechanism 21, a detailed illustration and description thereof appears to be unnecessary.
OPERATION Under normal conditions, the doors l5 and 20 will both be closed with the distal edge of the door 15 in registry with, and close enough to, the distal edge of the door 20 to hold the trigger bolt 48 of each of the latch mechanisms 21 and 64 in the retracted position of FIG. 3. If desired, the door 15 may carry a wear plate 66 positioned to register with each of the trigger bolts. The latchbolt 27 will be seated in the socket of the keeper 28 and the blocker 39 will be positioned in the path of the shoulder 37 to prevent affirmatively retraction of the bolt 27. Thus, the door 20 will be affirmatively locked in closed position, while the door 15 will be latched, but availa' ble for free use by normal traffic. Thus normal traffic will be encouraged to use only the door I5.
However, when the door I5 is moved even slightly in an opening direction, its distal edge will move out of registry with the edge 22 of the door 20, thereby releasing the trigger bolt 48. Immediately, the spring 45 will move the trigger 43 in a clockwise direction, the abutment element 47 will push the trigger bolt 48 to its position illustrated in FIG. 5 and the nose 44 of the trigger will engage the cars 63 of the blocker means 39 to overcome the spring 41 and move said blocker means to the position of FIG. 5 thus removing the blocker means from the path of the shoulder 37 on the ratchet member 65. Now, if even gentle opening pressure is exerted against the door 20, the cooperating cam surfaces 58 and 59 will force downwardly the latchbolt 27, the actuator rod 29, the sleeve 31 and the ratchet member 65. As the ratchet member 65 moves downwardly, its teeth 38 will cooperate with the catch pin 46. As the toe 57 of the trip ratchet 54 leaves the socket of the keeper 28, the spring 61 will move the trip ratchet in a counterclockwise direction whereby the teeth 56 will click past the catch plate 25 until downward movement of the latchbolt 27 is completed. As the toe 57 leaves the tongue 60 of the keeper, engagement of a tooth 56 with the catch plate 25 will retain the latch bolt 27 in its lowermost, depressed or retracted position. Thus, even if the now-exposed trigger bolt 48 is inadvertently or maliciously depressed to disengage the catch pin 46 from the teeth 38, the latch bolt 27 and its associated parts will nevertheless be retained in retracted position by the trip ratchet 54.
When the door 20 returns toward closed position, the toe 57 will engage the tongue 60 of the keeper 28 as the latchbolt moves into registry with said tongue, to disengage the trip ratchet from the catch plate 25. Normally, however, the teeth 38 will still be in engagement with the catch pin 46 so that the latchbolt will not be released to move into the socket of the keeper 28 at the moment of disengagement of the trip ratchet from the catch plate. However, from the moment of engagement of the toe 57 with the tongue 60, the trip ratchet will be held out of engagement with the catch plate 25 so that the latch bolt 27 will be dominated exclusively by the spring 32 and the trigger 43.
When the door 15 is closed, subsequent to closure of the door 20, its wear plate 66 will engage the right hand cammed surface 52 of the trigger bolt 48 to force that trigger bolt toward the left as viewed in FIG. 3, to the position of FIG. 3. As the trigger bolt so moves, its cooperation with the abutment element 47 will force the trigger 43 in a counterclockwise direction to the position of FIG. 3. Immediately before actuation of the trigger bolt 48 by the wear plate 66, the parts will be in the positions of FIG. 6. As the trigger 43 begins to move, the blocker means 39 will also begin to move in a counterclockwise direction until it comes into contact with the sleeve 31. When the movement of the trigger 3 has been continued sufficiently to disengage the catch pin 46 from the teeth 38, the spring 32 will force the actuator rod 29 and latchbolt 27 upwardly to engage said latch bolt in the keeper socket. As the sleeve 31 moves upwardly with the rod 29, its shoulder 37 will pass the upper end of the blocker means 39, whereupon the blocker means will be released to return to the position of FlG. 3 under the influence of the spring 41. Now, for so long as the door remains in closed condition, the door will remain affirmatively locked.
if, after both doors have been opened, the door 15 should return to closed position before the door 20 achieves closed position, it will be apparent that the actuation of the trip ratchet54 will be the same as above described but that the actuator rod 29 and the latch bolt 27 will be held in retracted position by the catch pin 46 until, as the door 20 approaches closed position, the left hand cammed surface 52 of the trigger bolt 48 will engage the wear plate 66 on the previously closed door 15 whereby said trigger bolt will be forced inwardly to shift the trigger 43 to the position of FIG. 3. Thereupon, the actuator rod 29 will be released to move upwardly to seat the latch bolt 27 in the keeper socket and the blocker means 39 will move into blocking relation with the shoulder 37 in the manner above described.
lt will be clear, of course, that if the door 20 is equipped with the second flush bolt latch mechanism 64 which is suggested in FIG. 1 and described above, that latch mechanism will operate simultaneously with the mechanism 21 and in precisely the same way.
Thus, it will be seen that, through the provision of the latch mechanism herein disclosed, we have provided an arrangement in which nonnal traffic through one only of a pair of mating doors will be encouraged and, to an extent at least, enforced; yet the relatively inactive door will at all times be readily available to accommodate panic traffic. At the same time, we have provided an arrangement which is less expensive than for instance, that illustrated in FIG. 1 of the aboveidentified Foster US. Pat. No. 3,149,864, in that only one of the two doors must be provided with a panic bar and with outside hardware. Still further, our flush bolt latch mechanism is a significant improvement over the arrangement illustrated in FIGS. 14 and 15 of said U.S. Pat. No. 3,149,864 in that it is wholly automatic in operation and requires no separate manipulation to release the door 20 for panic traffic.
While we have illustrated and described our invention in use in an assembly in which the active door 15 is equipped with a concealed vertical-rod type of latch assembly, it will be apparent to those skilled in the art that the invention is indifferent to the kind of latch mechanism used on the active door and that a rim-type or mortise-type panic latch assembly on the door 15 could cooperate with a keeper or strike on the inactive door 20.
We claim as our invention:
1. Latch mechanism for a hinged closure comprising a latchbolt mounted adjacent one end of said closure adjacent the edge of said closure remote from its hinge axis for movement between projected and retracted positions relative to said closure end, an actuator rod mounted for reciprocation near said closure edge and operatively connected to said bolt, spring means biasing said rod toward bolt-projected position, blocker means mounted for movement between a first position affirmatively blocking said rod against bolt-retracting movement and a second position permitting such bolt-retracting rod movement, said blocker means being biased toward such blocking position, trigger means mounted adjacent said rod and said blocker means for movement between an advanced position and a retracted position, said trigger means being biased toward said advanced position in which it engages and retains said blocker means in its second position, means moving with said trigger means for cooperative engagement with said rod only when said trigger means is in its advanced position and said rod is in bolt-retracted position to retain said rod against movement toward bolt-projected position and means for moving said trigger means to its retracted position.
2. The latch mechanism of claim 1 including catch means carried adjacent said closure end, and a trip element movably carried by said latch bolt and engageable with said catch means only when said bolt is retracted.
3. The latch mechanism of claim 2 including spring means urging said trip element toward engagement with said catch means.
4. The latch mechanism of claim 3 in which said trip element is, at times, nested within said latch bolt, said trip element being formed with a tooth for engagement with said catch element when said bolt is retracted and having a distal toe projecting in a common direction but beyond said tooth.
5. The latch mechanism of claim 1 in which said means for moving said trigger means to its retracted position is accessible only at said remote edge of said closure.
6. The latch mechanism of claim 1 in which said means for moving said trigger means to its retracted position is a trigger bolt disposed in an opening in said remote edge of said closure with its proximal end operatively engaging said trigger means,
said trigger bolt being provided with means limiting the degree of projection of its distal end beyond said remote closure edge and being movable to a position in which its distal end is substantially flush with said remote door edge.
7. The latch mechanism of claim'6 in which said trigger bolt is mounted for oscillation about an axis substantially parallel with the hinge axis of said closure and its distal region is cammed about an axis substantially parallel with the hinge axis of said closure.
8. Closure means for a portal having a substantially horizontal lintel, a substantially horizontal sill and opposed jambs, said closure means comprising a first closure member hinged to one of said jambs and provided with latch means cooperating with keeper means, a panic bar carried by said first closure member and operatively connected to retract said latch means, a second closure member hinged to the other of said jambs and provided with second latch means cooperating with second keeper means at one of said horizontal members, spring means yieldably urging said second latch means into restraining engagement with said second keeper means said second latch means and second keeper means providing cooperating surfaces effective to retract said second latch means in response to pressure exerted on said second closure member in an opening direction, blocker means carried by said second closure member for affirmatively preventing retraction of said second latch means at times and biased toward such retraction-preventing relation, means carried by said second closure member and cooperative with said blocker means at times to move and hold said blocker means out of such retraction-preventing relation, and means carried by said second closure member and engaged by said first closure member only when both closure members are in closed position to move said last-named means out of cooperative relation to said blocker means and to release said blocker means to assume such retraction-preventing relation.
9. In combination, a pair of mating doors hinged at their respectively remote edges to close a doorway, latch means carried adjacent the free edge of one of said doors, a panic bar carried by said one door and operatively connected to retract said latch means, second latch means carried adjacent the free edge of the other of said doors and normally yieldable to release said other door.in response to opening pressure impressed upon said other door, and means normally protruding from said free edge of said other door for engagement by the free edge of said one door only when both doors are in closed position and effective, when so engaged, affirmatively to prevent yielding of said second latch means.
10. in combination, a pair of mating doors hinged at their respectively remote edges to close a doorway, latch means carried adjacent the free edge of one of said doors, a panic bar carried by said one door and operatively connected to retract having a portion disposed, when said other door is closed, in the closing path of the free edge of said one door.