Dead-locking latch bolt mechanism

Claim 2

A deadlocking latch bolt mechanism comprising a bolt housing, a latch bolt slidably mounted in said housing and having a tubular stem fixed thereto and extending rearward therefrom a distance not less than the throw of the bolt, said stem having a rearwardly-presented stop face, a rod-shaped tailpiece telescopically mounted in said stem in coaxially supporting relation therewith and having limited axial lost motion therein, said tailpiece having a head at its rear end for retraction engagement with the retractor of a lock mechanism, a locking dog mounted in said housing and having a forwardly-presented dogging end, said dog having a dogging position in which said dogging end lies in the path of said stop face of the stem to block retraction of the bolt and a release position in which said end lies out of said path so as to permit such retraction, said dog also having a cam portion which includes a sloping cam surface rearward of said dogging end and which in dogging position of the dog projects inward of the inner surface of the stem and into interfering relation with the tailpiece, said tailpiece having a groove therein which has an inactive forward position aligned with said cam portion so as to receive the same and allow the dog to assume its dogging position, and which groove has an active rearward position to which it is moved by rearward movement of the tailpiece relative to the stem and in which its forward end is operative to engage said sloping cam surface of the dog and move the dog outward sufficiently to position its dogging end out of the path and its sloping cam surface in the path of said stop face of the stem so as to cause the dog to ride past such stop face and allow retraction of the bolt upon further rearward movement of the tailpiece, and an auxiliary bolt slidable in said housing and means movable therewith for moving the locking dog to release position when the auxiliary bolt is in projected position and permitting the dog to assume its dogging position when the auxiliary bolt is retracted relative to the latch bolt.

Claim 3

A deadlocking latch bolt mechanism as in claim 1, further comprising a timing groove in the tailpiece spaced forwardly from said cam-receiving groove, and a stop member fixed to the stem and engaged in the timing groove, the timing groove being axially longer than the stop member by a predetermind amount so as to limit the lost motion between the tailpiece and stem.

Claim 4

A deadlocking latch bolt mechanism as in claim 1, in which said tailpiece has slidable telescopic engagement with said stem over a long length thereof greater than the inside diameter of the stem so as to form a coaxially self-sustaining assembly, and said bolt has slidable bearing engagement with the forward end of said housing, and bearing means at the rear of the housing and slidably supporting the tailpiece to thereby support said assembly and the bolt in coaxial slidable relation with the housing.

Claim 5

A deadlocking latch bolt mechanism as in claim 1, which includes a bolt-advancing spring biasing said latch bolt toward projected position, and biasing means acting between the tailpiece and latch bolt to urge the tailpiece forward in its lost motion relative to the stem, said biasing means being weaker than said advancing spring so that rearward pull on the tailpiece by the retractor will first move the tailpiece relative to the latch bolt to dispose said tailpiece groove in its active position and thereafter retract the latch bolt.

Claim 6

A deadlocking latch bolt mechanism as in claim 4, in which said locking dog is pivotally mounted at the rear of the housing and has a forward dogging end, and said tailpiece groove has a cam surface formed at its forward end for engagement with said cam surface on the dog.

Claim 7

A deadlocking latch bolt mechanism, comprising a bolt housing, a latch bolt slidably mounted in said housing and having a rearward-extending tubular stem fixed thereto, a rod-shaped tailpiece telescopically mounted in said stem and having limited axial lost motion therein, said tailpiece having a head at its rear end for retraction engagement with the retractor of a lock mechanism, a locking dog mounted in said housing and having a dogging position in which it lies in the path of said stem to block retraction of the bolt and a release position in which it permits such retraction, cam means on said tailpiece having an inactive forward position and an active rearward position to which it is moved by rearward movement of the tailpiece relative to the stem, said cam means being operative in said active position to move the dog from its dogging position to its release position, an auxiliary bolt slidable in said housing and means movable therewith for moving the locking dog to release position when the auxiliary bolt is in projected position and permitting the dog to assume its dogging position when the auxiliary bolt is retracted relative to the latch bolt, biasing means acting between the tailpiece and latch bolt to urge the tailpiece forward in its lost motion relative to the stem to a position in which it disposes the cam means in its inactive forward position, and a bolt-advancing spring biasing said latch bolt toward projected position, said biasing means between the tailpiece and latch bolt being weaker than said advancing spring so that rearward pull on the tailpiece by the retractor will first move the tailpiece relative to the latch bolt to dispose said cam means in its active position and thereafter retract the latch bolt, said locking dog being pivotally mounted at the rear of the housing and having a forward dogging end which in dogging position lies adjacent the side of the tailpiece in the path of said stem, said cam means comprising a cam element formed on said tailpiece which in its forward inactive position during rearward movement of the bolt allows the dog to engage the stem before it engages said cam element, and in its active rearward position engages the dog to move it out of the path of the stem before the dog engages the stem, said cam element being the forward portion of a circumferential groove in the rod-shaped tailpiece, and said locking dog having a cooperating cam element which lies in said groove when the dog is in dogging position.

Claim 8

A deadlocking latch bolt mechanism, comprising a bolt housing, a latch bolt slidably mounted in said housing and having a rearward-extending tubular stem fixed thereto, a rod-shaped tailpiece telescopically mounted in said stem and having limited axial lost motion therein, said tailpiece having a head at its rear end for retraction engagement with the retractor of a lock mechanism, a locking dog mounted in said housing and having a dogging position in which it lies in the path of said stem to block retraction of the bolt and a release position in which it permits such retraction, cam means on said tailpiece having an inactive forward position and an active rearward position to which it is moved by rearward movement of the tailpiece relative to the stem, said cam means being operative in said active position to move the dog from its dogging position to its release position, an auxiliary bolt slidable in said housing and means movable therewith for moving the locking dog to release position when the auxiliary bolt is in projected position and permitting the dog to assume its dogging position when the auxiliary bolt is retracted relative to the latch bolt, biasing means acting between the tailpiece and latch bolt to urge the tailpiece forward in its lost motion relative to the stem to a position in which it disposes the cam means in its inactive forward position, and a bolt-advancing spring biasing said latch bolt toward projected position, said biasing means between the tailpiece and latch bolt being weaker than said advancing spring so that rearward pull on the tailpiece by the retractor will first move the tailpiece relative to the latch bolt to dispose said cam means in its active position and thereafter retract the latch bolt, said locking dog being pivotally mounted at the rear of the housing and having a forward dogging end which in dogging position lies adjacent the side of the tailpiece in the path of said stem, said cam means comprising a cam element formed on said tailpiece which in its forward inactive position during rearward movement of the bolt allows the dog to engage the stem before it engages said cam element, and in its active rearward position engages the dog to move it out of the path of the stem before the dog engages the stem, said cam element being the forward portion of a circumferential groove in the rod-shaped tailpiece, and said locking dog having a cooperating cam element which lies in said groove when the dog is in dogging position.

Claim 9

A deadlocking latch bolt mechanism, comprising a bolt housing, a latch bolt slidably mounted in said housing and having a rearward-extending tubular stem fixed thereto, a rod-shaped tailpiece telescopically mounted in said stem and having limited axial lost motion therein, said tailpiece having a head at its rear end for retraction engagement with the retractor of a lock mechanism, a deadlocking dog mounted in said housing and having a dogging position in which it lies in the path of said stem to block retraction of the bolt and a release position in which is permits such retraction, cam means on said tailpiece having an inactive forward position and an active rearward position to which it is moved by rearward movement of the tailpiece relative to the stem, said cam means being operative in said active position to move the dog from its dogging position to its release position, an auxiliary bolt slidable in said housing and means movable therewith for moving the locking dog to release position when the auxiliary bolt is in projected position and permitting the dog to assume its dogging position when the auxiliary bolt is retracted relative to the latch bolt, a spring extending longitudinally of said housing and urging one of said bolts to projected position, a support at the rear of the housing, said deadlocking dog being pivoted at the rear of said housing, extending forward therefrom, and having a pressure lug extending inward of its pivot axis, and a foot lever having a heel portion fulcrummed on said support and having a toe portion engaging said pressure leg, said spring being supported by and reacting against said foot lever at a point between its heel and toe portions so as to urge the foot lever about its fulcrum in a direction to press on the pressure lug of the deadlocking dog and thereby bias the deadlocking dog inward toward its deadlocking position.

Claim 10

A deadlocking latch bolt mechanism, comprising a bolt housing, a latch bolt slidably mounted in said housing and having a rearward-extending tubular stem fixed thereto, a rod-shaped tailpiece telescopically mounted in said stem and having limited axial lost motion therein, said tailpiece having a head at its rear end for retraction engagement with the retractor of a lock mechanism, a deadlocking dog mounted in said housing and having a dogging position in which it lies in the path of said stem to block retraction of the bolt and a release position in which is permits such retraction, cam means on said tailpiece having an inactive forward position and an active rearward position to which it is moved by rearward movement of the tailpiece relative to the stem, said cam means being operative in said active position to move the dog from its dogging position to its release position, an auxiliary bolt slidable in said housing and means movable therewith for moving the locking dog to release position when the auxiliary bolt is in projected position and permitting the dog to assume its dogging position when the auxiliary bolt is retracted relative to the latch bolt, a spring extending longitudinally of said housing and urging one of said bolts to projected position, a support at the rear of the housing, said deadlocking dog being pivoted at the rear of said housing, extending forward therefrom, and having a pressure lug extending inward of its pivot axis, and a foot lever having a heel portion fulcrummed on said support and having a toe portion engaging said pressure leg, said spring being supported by and reacting against said foot lever at a point between its heel and toe portions so as to urge the foot lever about its fulcrum in a direction to press on the pressure lug of the deadlocking dog and thereby bias the deadlocking dog inward toward its deadlocking position.

Claim 11

A deadlocking latch bolt mechanism as in claim 7 which includes two springs on opposite sides of said tailpiece, respectively for urging the latch bolt and auxiliary bolt to projected positions, said foot lever being arranged to support and sustain the reaction of both of said springs.

Claim 12

A deadlocking latch bolt mechanism as in claim 8, in which said rear support carries guide pins extending axially through said springs and said foot lever is a C-shaped member having bifuricated ends engaged about said pins.

Claim 13

A deadlocking latch bolt mechanism, comprising a generally cylindrical bolt housing, a latch bolt slidable in said housing and including a bolt member and a rearward-extending tailpiece, said bolt member having a latch side face extending chordally of said housing, an auxiliary bolt slidably mounted against said latch side face, said auxiliary bolt being narrower than the chordal side face of the latch bolt so as to form longitudinal angular grooves at opposite sides of the auxiliary bolt, and low-friction bearing blocks mounted in said grooves.

Claim 14

A deadlocking latch bolt mechanism, comprising a generally cylindrical bolt housing, a latch bolt slidable in said housing and including a bolt member and a rearward-extending tailpiece, said bolt member having a latch side face extending chordally of said housing, an auxiliary bolt slidably mounted against said latch side face, said auxiliary bolt being narrower than the chordal side face of the latch bolt so as to form longitudinal angular grooves at opposite sides of the auxiliary bolt, and low-friction bearing blocks mounted in said grooves.

Claim 15

A deadlocking latch bolt mechanism as in claim 10, with the addition of a stop plate fixed to the rear face of said latch bolt member and having arms extending into said angular grooves, said bearing blocks being engaged over said arms so as to move with the latch bolt, and a plate closing said grooves at the outer end of said housing, against which the bearing blocks engage to stop outward movement of the latch bolt.

Claim 16

A deadlocking latch bolt mechanism as in claim 11 with the addition of a stop segment fixed to the inner end of said auxiliary bolt and overlying the rear faces of said bearing blocks so as to engage the same to stop forward movement of the auxiliary bolt relative to the latch bolt.

Claim 17

A deadlocking latch bolt mechanism, comprising a tubular bolt housing, a latch bolt slidably mounted in the forward end of said housing and having a rearward-extending tubular stem fixed thereto, a rod-shaped tailpiece telescopically mounted in said stem and having limited axial lost motion therein, a tailpiece-biasing spring or the like acting between the bolt and tailpiece and urging the tailpiece forward with respect to the bolt, said tailpiece having a head at its rear end for retraction engagement with the retractor of a lock mechanism, a locking dog pivotally mounted at the rear of the housing and extending foward along side the tailpiece and having a forward dogging end which normally lies in a dogging position in the path of said stem to block retraction of the bolt, said dog being pivotally movable outward from said dogging position to a release position in which it lies out of the path of the stem so as to permit retraction of the bolt, spring means biasing the dog to said normal dogging position, a cam element formed on the tailpiece opposite a portion of said locking dog, said cam element having a normal position in which it clears the locking dog to permit the same to assume its dogging position when the tailpiece is forward with respect to the bolt, said cam element being movable to a position to engage the locking dog upon rearward lost-motion movement of the tailpiece and to move the locking dog to its release position so as to permit rearward movement of the tailpiece to retract the bolt, a foot lever having a heel portion fulcrumed on a support at the rear of said bolt housing and having a toe portion engaged with said locking dog so as to tilt the same inward to its normal locking position, and a spring acting between one of said bolts and said foot lever to urge the bolt forward and urge the lever in a direction to tilt the locking dog to its dogging position.

Claim 18

A deadlocking latch bolt mechanism, comprising a tubular bolt housing, a latch bolt slidably mounted in the forward end of said housing and having a rearward-extending tubular stem fixed thereto, a rod-shaped tailpiece telescopically mounted in said stem and having limited axial lost motion therein, a tailpiece-biasing spring or the like acting between the bolt and tailpiece and urging the tailpiece forward with respect to the bolt, said tailpiece having a head at its rear end for retraction engagement with the retractor of a lock mechanism, a locking dog pivotally mounted at the rear of the housing and extending foward along side the tailpiece and having a forward dogging end which normally lies in a dogging position in the path of said stem to block retraction of the bolt, said dog being pivotally movable outward from said dogging position to a release position in which it lies out of the path of the stem so as to permit retraction of the bolt, spring means biasing the dog to said normal dogging position, a cam element formed on the tailpiece opposite a portion of said locking dog, said cam element having a normal position in which it clears the locking dog to permit the same to assume its dogging position when the tailpiece is forward with respect to the bolt, said cam element being movable to a position to engage the locking dog upon rearward lost-motion movement of the tailpiece and to move the locking dog to its release position so as to permit rearward movement of the tailpiece to retract the bolt, a foot lever having a heel portion fulcrumed on a support at the rear of said bolt housing and having a toe portion engaged with said locking dog so as to tilt the same inward to its normal locking position, and a spring acting between one of said bolts and said foot lever to urge the bolt forward and urge the lever in a direction to tilt the locking dog to its dogging position.

Claim 19

A deadlocking latch bolt mechanism, comprising a bolt housing, a latch bolt slidably mounted in said housing and having a rearward-extending stem fixed thereto, a tailpiece connected with said stem and having limited axial lost motion with respect to the stem, said tailpiece having means at its rear end for retraction by the retractor of a lock mechanism, a locking dog pivotally mounted at the rear of said housing, extending forward therefrom and having a pressure lug extending inward of its pivot axis, said dog having a dogging position in which it lies in blocking relation with said stem to block retraction of the bolt and a release position in which it permits such retraction, and a foot lever having a heel portion fulcrumed on a support at the rear of the housing and having a toe portion engaging said pressure lug, a bolt-advancing spring supported by and reacting against said foot lever at a point between its heel and toe portions so as to urge the foot lever about its fulcrum in a direction to press on the pressure lug of the deadlocking dog and thereby bias the deadlocking dog inward toward its deadlocking position, dog-controlling means on said tailpiece having an inactive forward position and an active rearward position to which it is moved by rearward movement of the tailpiece relative to the stem, said means being operative in said active position to move the dog from its dogging position to its release position, and an auxiliary bolt slidable in said housing and means movable therewith for moving the locking dog to release position when the auxiliary bolt is in projected position and permitting the dog to assume its dogging position when the auxiliary bolt is retracted relative to the latch bolt.

Claim 20

A deadlocking latch bolt mechanism, comprising a bolt housing, a latch bolt slidably mounted in said housing and having a rearward-extending stem fixed thereto, a tailpiece connected with said stem and having limited axial lost motion with respect to the stem, said tailpiece having means at its rear end for retraction by the retractor of a lock mechanism, a locking dog pivotally mounted at the rear of said housing, extending forward therefrom and having a pressure lug extending inward of its pivot axis, said dog having a dogging position in which it lies in blocking relation with said stem to block retraction of the bolt and a release position in which it permits such retraction, and a foot lever having a heel portion fulcrumed on a support at the rear of the housing and having a toe portion engaging said pressure lug, a bolt-advancing spring supported by and reacting against said foot lever at a point between its heel and toe portions so as to urge the foot lever about its fulcrum in a direction to press on the pressure lug of the deadlocking dog and thereby bias the deadlocking dog inward toward its deadlocking position, dog-controlling means on said tailpiece having an inactive forward position and an active rearward position to which it is moved by rearward movement of the tailpiece relative to the stem, said means being operative in said active position to move the dog from its dogging position to its release position, and an auxiliary bolt slidable in said housing and means movable therewith for moving the locking dog to release position when the auxiliary bolt is in projected position and permitting the dog to assume its dogging position when the auxiliary bolt is retracted relative to the latch bolt.

Claim 21

A deadlocking latch bolt mechanism, comprising a bolt housing, a latch bolt slidably mounted in said housing and having an elongated tubular stem fixed thereto and extending rearward therefrom, a rod-shaped tailpiece telescopically received in said stem and having slidable engagement therewith over a substantial length thereof greater than the diameter of the rod so as to form a stiff coaxially self-sustaining assembly in which the tailpiece has limited axial lost motion in the stem, said tailpiece having a head at its rear end for retraction engagement with the retractor of a lock mechanism, said bolt being slidably supported in said housing at the front end of said coaxially self-sustaining assembly and said tailpiece being slidably supported at the rear end of said housing, so as to provide widely spaced slidable bearing supports for said self-sustaining assembly to thereby support the same and the bolt in coaxial slidable relation with the housing, a locking dog mounted in said housing and having a dogging position in which it lies in blocking relation with said stem to block retraction of the bolt and a release position in which it permits such retraction, cam means on said tailpiece having an inactive forward position and an active rearward position to which it is moved by rearward movement of the tailpiece relative to the stem, said means being operative in said active position to move the dog from its dogging position to its release position, and an auxiliary bolt slidable in said housing and means movable therewith for moving the locking dog to release position when the auxiliary bolt is in projected position and permitting the dog to assume its dogging position when the auxiliary bolt is retracted relative to the latch bolt.

Claim 22

A deadlocking latch bolt mechanism, comprising a bolt housing, a latch bolt slidably mounted in said housing and having an elongated tubular stem fixed thereto and extending rearward therefrom, a rod-shaped tailpiece telescopically received in said stem and having slidable engagement therewith over a substantial length thereof greater than the diameter of the rod so as to form a stiff coaxially self-sustaining assembly in which the tailpiece has limited axial lost motion in the stem, said tailpiece having a head at its rear end for retraction engagement with the retractor of a lock mechanism, said bolt being slidably supported in said housing at the front end of said coaxially self-sustaining assembly and said tailpiece being slidably supported at the rear end of said housing, so as to provide widely spaced slidable bearing supports for said self-sustaining assembly to thereby support the same and the bolt in coaxial slidable relation with the housing, a locking dog mounted in said housing and having a dogging position in which it lies in blocking relation with said stem to block retraction of the bolt and a release position in which it permits such retraction, cam means on said tailpiece having an inactive forward position and an active rearward position to which it is moved by rearward movement of the tailpiece relative to the stem, said means being operative in said active position to move the dog from its dogging position to its release position, and an auxiliary bolt slidable in said housing and means movable therewith for moving the locking dog to release position when the auxiliary bolt is in projected position and permitting the dog to assume its dogging position when the auxiliary bolt is retracted relative to the latch bolt.

Claim 23

A deadlocking latch bolt mechanism as in claim 15 in which said bolt member has a latch side face extending chordally of said bolt housing, said auxiliary bolt is slidably mounted against said latch side face and is narrower than said chordal side face so as to form longitudinal angular grooves at opposite sides of the auxiliary bolt, and low-friction bearing blocks mounted in said grooves to slidably support the front end of said bolt and tailpiece assembly.

Claim 24

A deadlocking latch bolt mechanism as in claim 15 in which said housing is cylindrical, said auxiliary bolt is slidably mounted in a guiding groove in the side face of said latch bolt, and has a substantially cylindrical outer face in substantially mating bearing engagement with he front end of the cylindrical housing so as to support the latch bolt for coaxial sliding movement therein.

Claim 25

A deadlocking latch blt mechanism, comprising a bolt housing, a latch bolt slidably mounted in said housing and having an elongated rearward-extending tubular stem fixed thereto, the internal bore of said stem having a shoulder formed therein adjacent its forward end, a rod-shaped tailpiece telescopically mounted in the bore of said stem and having limited lost motion therein, said tailpiece having a shoulder adjacent its forward end and a reduced diameter end portion extending beyond said tailpiece shoulder and having a cap at its forward end, a reaction washer mounted about said tailpiece end portion and shaped to engage said tailpiece shoulder in thrust relation, a spring about said tailpiece end portion and compressed between said cap and washer so as to urge the washer rearward and urge the cap and tailpiece forward relative to the washer, said washer being fixed in the bore of the stem against the shoulder therein so as to support the adjacent end of the spring in fixed position in the stem against rearward movement and thereby cause the spring to bias the cap and tailpiece forward relative to the stem, a locking dog mounted in said housing and having a dogging position to which it is biased and in which it lies in blocking relation relative to said stem to block retraction of the bolt, and a release position in which it permits such retraction, means on said tailpiece responsive to rearward lost motion movement of the tailpiece relative to the stem, against the bias of said spring, for moving said dog from its dogging position to its release position, and an auxiliary bolt slidable in said housing and means movable therewith for independently moving the locking dog to release position.

Claim 26

A deadlocking latch blt mechanism, comprising a bolt housing, a latch bolt slidably mounted in said housing and having an elongated rearward-extending tubular stem fixed thereto, the internal bore of said stem having a shoulder formed therein adjacent its forward end, a rod-shaped tailpiece telescopically mounted in the bore of said stem and having limited lost motion therein, said tailpiece having a shoulder adjacent its forward end and a reduced diameter end portion extending beyond said tailpiece shoulder and having a cap at its forward end, a reaction washer mounted about said tailpiece end portion and shaped to engage said tailpiece shoulder in thrust relation, a spring about said tailpiece end portion and compressed between said cap and washer so as to urge the washer rearward and urge the cap and tailpiece forward relative to the washer, said washer being fixed in the bore of the stem against the shoulder therein so as to support the adjacent end of the spring in fixed position in the stem against rearward movement and thereby cause the spring to bias the cap and tailpiece forward relative to the stem, a locking dog mounted in said housing and having a dogging position to which it is biased and in which it lies in blocking relation relative to said stem to block retraction of the bolt, and a release position in which it permits such retraction, means on said tailpiece responsive to rearward lost motion movement of the tailpiece relative to the stem, against the bias of said spring, for moving said dog from its dogging position to its release position, and an auxiliary bolt slidable in said housing and means movable therewith for independently moving the locking dog to release position.