Door latch

Claim 2

A locking mechanism for use with a door comprising, in combination: a structure having dimensions to form at least part of the free end of said door, said structure being provided with an elongate recess extending the height of the door; an upper bolt and a lower bolt disposed in said recess and reciprocably movable relative to said structure between a first position in which their ends project above and below the top and the bottom of said door structure respectively, and a second position in which said bolt ends are retracted; means normally biasing both of said bolts to first position; retracting means disposed entirely within said recess in a midregion along its length and being manually operable to retract said bolts against said bias to second position; in which said structure comprises a plate of dimensions to cover the free edge of said one door from top to bottom and having guide means formed along a central vertical section of its length on one side thereof for confining said bolts and said retracting members to movement in a vertical direction, said guide means comprising structures of size to fit within an elongate recess formed in the free edge of the material of the door and extending throughout its height and including a track, said retraction members being mounted upon the track and confined by the track to movement within said guide means.

Claim 3

A locking mechanism for use with a door comprising, in combination: a structure having dimensions to form at least part of the free end of said door, said structure being provided with an elongate recess extending the height of the door; an upper bolt and a lower bolt disposed in said recess and reciprocably movable relative to said structure between a first position in which their ends project above and below the top and the bottom of said door structure respectively, and a second position in which said bolt ends are retracted; means normally biasing both of said bolts to first position; retracting means disposed entirely within said recess in a midregion along its length and being manually operable to retract said bolts against said bias to second position; in which said bolts are generally cylindrical including cam means for camming said bolts to said second position upon closure of said one door comprising a follower surface formed at the end of each bolt in the form of a rounded end; and in which said structure comprises a plate of dimensions to cover the height and width of the free edge of said one door and having its central vertical section recessed to form a channel of uniform depth and width throughout its length; cover means for covering said channel along all but a midregion along its length comprising an upper cover section of dimensions to cover the upper section of the channel above said midregion and a lower cover section of dimensions to cover a lower section below said midregion; a pair of guides disposed within the upper section of said channel and a pair of guides disposed within the lower section of said channel, at least one guide of each pair being fixed against movement, said upper bolt being reciprocably mounted for vertical movement in said one guide of the upper pair of guides and said lower bolt being reciprocably mounted for vertical movement in said one guide of said lower pair of guides; a pair of retraction members disposed within said channel at said midregion and movable therealong, one being movable upwardly into engagement with the lower end of said upper cover section and the other being movable downwardly into engagement with the upper end of said lower cover section; the upper retraction member having connection to the upper bolt and the lower retraction member having connection to the lower bolt; means for biasing said upper bolt and said retraction member upwardly to urge said upper retraction member into engagement With the lower end of said upper section of the cover and means for urging the lower bolt and lower retraction member downwardly and tending to engage said lower retraction member with the upper end of said lower cover section.

Claim 4

A locking mechanism for use with a door comprising, in combination: a structure having dimensions to form at least part of the free end of said door, said structure being provided with an elongate recess extending the height of the door; an upper bolt and a lower bolt disposed in said recess and reciprocably movable relative to said structure between a first position in which their ends project above and below the top and the bottom of said door structure respectively, and a second position in which said bolt ends are retracted; means normally biasing both of said bolts to first position; retracting means disposed entirely within said recess in a midregion along its length and being manually operable to retract said bolts against said bias to second position; in which said bolts are generally cylindrical including cam means for camming said bolts to said second position upon closure of said one door comprising a follower surface formed at the end of each bolt in the form of a rounded end; and in which said structure comprises a plate of dimensions to cover the height and width of the free edge of said one door and having its central vertical section recessed to form a channel of uniform depth and width throughout its length; cover means for covering said channel along all but a midregion along its length comprising an upper cover section of dimensions to cover the upper section of the channel above said midregion and a lower cover section of dimensions to cover a lower section below said midregion; a pair of guides disposed within the upper section of said channel and a pair of guides disposed within the lower section of said channel, at least one guide of each pair being fixed against movement, said upper bolt being reciprocably mounted for vertical movement in said one guide of the upper pair of guides and said lower bolt being reciprocably mounted for vertical movement in said one guide of said lower pair of guides; a pair of retraction members disposed within said channel at said midregion and movable therealong, one being movable upwardly into engagement with the lower end of said upper cover section and the other being movable downwardly into engagement with the upper end of said lower cover section; the upper retraction member having connection to the upper bolt and the lower retraction member having connection to the lower bolt; means for biasing said upper bolt and said retraction member upwardly to urge said upper retraction member into engagement With the lower end of said upper section of the cover and means for urging the lower bolt and lower retraction member downwardly and tending to engage said lower retraction member with the upper end of said lower cover section.

Claim 5

The invention defined in claim 2, in which said bolts are formed with a shoulder at a point along their length and said bias means comprises a pair of coiled springs each wound about a respectively associated one of said bolts and trapped between the shoulder of its bolt and one of said guides.

Claim 6

The invention defined in claim 3, in which said recessed portion of said plate comprises a track defined by conformations on its opposing surfaces and in which said retraction means are disposed within said track and have complementary conformations on their surfaces by which they are confined to vertical movement entirely within said recess.

Claim 7

A locking mechanism for use with a door comprising in combination: an elongated channel member having height to extend the height of a door and having its channel extending over that height; means comprising a removable cover plate for covering at least all but a central region of a channel recess; an upper bolt and a lower bolt disposed in said recess and reciprocably movable relative to said channel and cover plate between a first position in which their ends project above and below the top and bottom of said channel member respectively, and a second position in which said bolt ends are retracted, said bolts being carried by and removable with said cover member; bias means normally biasing said bolts to first position; and retracting means disposed within said central region of said recess; said biasing means comprising springs carried by and removable with said cover plate.

Claim 8

A locking mechanism for use with a door comprising in combination: an elongated channel member having height to extend the height of a door and having its channel extending over that height; means comprising a removable cover plate for covering at least all but a central region of a channel recess; an upper bolt and a lower bolt disposed in said recess and reciprocably movable relative to said channel and cover plate between a first position in which their ends project above and below the top and bottom of said channel member respectively, and a second position in which said bolt ends are retracted, said bolts being carried by and removable with said cover member; bias means normally biasing said bolts to first position; and retracting means disposed within said central region of said recess; said biasing means comprising springs carried by and removable with said cover plate.

Claim 9

The invention defined in claim 5, in which said cover plate is divided into two separately removable sections.

Claim 10

The invention defined to claim 6, including means for permitting assembly and disassembly of the cover plate and channel member and retracting means by sliding the cover plate endwise upon the channel member while precluding perpendicular separation comprising mating tracks and conformations.

Claim 11

The invention defined in claim 7, in which saId cover plate is divided into two separately removable sections and in which said retracting means comprises a pair of manually engageable retraction elements and means connecting them to respectively associated ones of said bolts, said bias means comprising a pair of bias springs carried by a respectively associated one of said cover plate sections normally biasing said retraction elements into engagement with an end of its respectively associated cover plate section whereby each cover plate section and its respectively associated bolt and spring and retraction element may be assembled on said channel member as a unit.