SECURITY DOOR LOCK

Abstract: A vertically elongated guide structure is recessed within a floor (12) adjacent a wall (10) having a door opening (14) formed therein with a door (16) swingably mounted from the wall (10). The guide structure (20) is positioned slightly outward of the side of the wall (10) from which the door (16) swings toward the open position. An elongated upstanding locking member (32) is guidingly supported from guide structure (20) for movement between a downwardly retracted position projecting only slightly above the level of the floor (12) and a raised position projecting appreciably above the door lower marginal edge (44) of the door (16) and is spring biased toward the extended position. Coacting latch structure (34, 36 and 38) allows free vertical movement of the lock member between its raised and retracted positions when the locking member (32) is in one limit position of oscillation and releasably latches the locking member (32) in the retracted position when the locking member (32) is angularly displaced to the other limit position of oscillation thereof.

Description: Description SECURITY DOOR LOCK BACKGROUND OF THE INVENTION Entrance doors for homes and apartments are conventionally provided with chain structures which limit swinging movement of the doors toward the open positions thereof, whereby a person answering a knock on the door or a door bell may open the door with the chain structure in operative position allowing the door to be opened only a slight amount. In this manner, the person answering the door may view through a narrow slot between the free swinging edge of the door and the door frame in order to view the person or persons on the other side of the door before opening the door fully. While these chain structures appear to offer the security proposed to be provided thereby, in actuality such chain structures may be readily torn from the associated door or from the associated door jamb by a sharp force being directed upon the exterior of the door. Accordingly, a need exists for an improved security door lock which will allow a door to be opened slightly but which will more securely prevent the door from being opened past the slightly open position thereof. Examples of previously known forms of security door locks including some of the general structural and operational features of the instant invention are disclosed in U.S. patent Nos. 1,526,698, 1,866,233, 2,450,145 and 4,303,266. BR EF DESCRIPTON OF THE INVENTION The door lock of the instant invention comprises a downwardly retractable and upwardly extendable floor mounted abutmemt positioned for engagement by the free swinging edge portion of the lower marginal edge of an associated door upon that door being opened slightly from its closed position. The abutment is spring biased toward an upwardly projected position and may be readily shifted toward a retracted position projecting only slightly above the level of the associated floor by downward foot pressure being applied thereto from above. In addition, the abutment member is supported in a guide structure recessed within the floor for limited oscillation about an upstanding axis. In one limit position of oscillation of the abutment or abutment member the latter may be freely downwardly displaced against the biasing action of the associated spring toward its retracted position and thereafter angularly displaced to its other limit position of angular displacement in order to releasably latch the abutment member in its downwardly retracted position. Thus, a retractable door security lock is provided which may be readily actuated as desired in the event a person answering a knock on the door or an associated door bell wishes to allow the door to be opened only a slight amount for the purpose of viewing the person or persons on the other side of the door. The main object of this invention is to provide a security door lock which may be readily OM usable by a person answering a knock on an associated door or a door bell and who wishes to allow the door to open only a slight amount. Another object of this invention is to provide a security door lock in accordance with the preceding object and which will offer considerable more security than the conventional chain-type security locks. Still another object of this invention is to provide a security door lock which is less obtrusive than the conventional chain type of security door lock. A further object of this invention is to provide an apparatus in accordance with the preceding objects and which may be used in conjunction with substantially all different types of horizontally swingable doors. A final object of this invention to be specifically enumerated herein is to provide a security door lock in accordance with the preceding objects and which will conform to conventional forms of manufacture, be of simple construction and easy to use so as to provide a device that will be economically feasible, long lasting and relatively trouble free in operation. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of the security door lock in an operative condition and in operative association with a partially open door; Figure 2 is an enlarged fragmentary vertical sectional view taken substantially upon the plane indicated by the section line 2-2 of Figure 1; Figure 3 is a top plan view of the security door lock; and Figure 4 is an exploded perspective view of the security door lock. DETAILED DESCRIPTION OF THE INVENTION Referring now more specifically to the drawings the numeral 10 generally designates a wall which projects upwardly from a horizontal floor 12 and has a door opening 14 formed therein with a door 16 hingedly supported from the wall for horizontal swinging between open and closed positions, as is conventional. Conventionally, a chain-type security lock (not shown) may be provided for the door 16 and operably connected between the door 16 and the frame opposing the free swinging edge of the door in order to releasably prevent the door 16 from swinging further toward a fully open position from the partially open position thereof illustrated in Figure 1. However, chain-type security locks are conventionally anchored relative to the associated door frame through the utilization of perhaps four wood screws and a sharp impact on the opposite side of the door to force the door to a full open position is often all that is required to rip the afore¬ mentioned four screws from the door frame and thus render the chain-type security lock inoperable. The security door lock of the instant invention is referred to in general by the reference numeral 18 and includes a cylindrical upstanding guide housing having a diametric rolled pin 22 secured across its lower end and opening upwardly at its upper end through an annular mounting plate 24 secured, as by welding, about the upper end of the housing 20. The mounting plate 24 includes peripherally spaced apertures 26 through which fasteners 28 may be secured in order to secure the housing in recessed position within a bore 30 provided therefore in the floor 12. The lock 18 additionally includes an elongated cylindrical locking member 32 which is slidably disposed within the housing 20 and projects through the open upper end thereof. The locking member 32 includes a radially projecting rolled stop and guide pin 34 carried by a lower end thereof and the pin 34 is slidably received within a longitudinal slot 36 formed in the housing 20. The slot 36 is J-shaped and includes a reverse and upturned lower end portion 38 into which the pin 34 may be received after the locking member 32 has been downwardly displaced from the upwardly projecting position thereof illustrated in Figure 2 of the drawings to a position with the pin 34 registered with the slot portion 38. Thereafter, the locking member 32 may be slightly angularly displaced in a clockwise direction as viewed from above in order to swing the pin 34 into the portion 38 of the slot 36. A compression spring 40 is disposed within the housing 20 between the rolled pin 22 and the lower end surface 42 of the locking member 32 and thereby upwardly biases the locking member 32 to its fully extended position limited by seated engagement of the pin 34 with the upper end of the slot 36. The security door lock 18 is recessed within the floor 12 in position for the locking member 32 to be abuttingly engaged by the lower marginal edge portion 44 of the door 16 adjacent the free swinging edge 46 thereof when the door 16 is swing from the fully closed position to the partially open position illustrated in Figure 1. In this manner, a very secure abutment against further opening of the door 16 is provided when the locking member 32 is disposed in its upwardly extended position. In order to downwardly displace the locking member 32 to its retracted position and to latch the locking member in its retracted position, a person may place his shoe over the upper end of the locking member 32 and downwardly depress the locking member 32 to a position with the pin 34 disposed in the lower end of the slot 36. There¬ after, the person may rotate his shoe in a clockwise direction and the serrated upper end surface 48 of the locking member 32 which projects slightly above the upper surface of the mounting plate 24 when the locking member 32 is in the retracted position creates sufficient friction between the shoe and the locking member 32 in order to impart OMPI clockwise angular displacement of the locking member 32 in a manner such that the pin 34 will be received in the portion 38 of the slot 36 and thus releasably latch the locking member 32 against upward displacement toward its fully extended position illustrated in Figure 2. When the locking member 32 is latched in its recessed position, the serrated upper end face 48 of the locking member 32 is disposed at an elevation spaced slightly below the lower marginal edge of the door 16 and slightly above the upper surface of the mounting plate 24. Thus, when it is desired to again upwardly displace the locking member 32 when answering a knock on the door or a door bell, a person may press his shoe downward upon the surface or face 48 and rotate his shoe in a counterclockwise direction thereby withdrawing the pin 34 from the portion 38 of the slot 36 and allowing the spring 40 to thereafter upwardly yieldingly bias the latching member 32 toward its fully extended position. The lock 18 may be used to lock rear doors of commercial buildings and thus to replace the conventional U-braces and the associated locking bar presently used in many instances. Further, the lock 18 may not be easily picked, unlocked or forced from outside the associated door. Also, the lock may be readily reached and unlocked by even small children in emergency situations. It is also pointed out that the lock 18 may be readily installed by inexperienced persons OMPI and further that the lock is simple in design, with few moving parts.

Claims: CLAIMS 1. In combination with a floor supporting an upstanding wall therefrom having a door opening formed therein and from which a horizontally swingable door, including a free swinging upstanding edge and a lower marginal edge spaced slightly above said door, is mounted for swinging movement, with said lower marginal edge spaced closely above said floor, toward and away from a position closing at least the lower portion of said opening and with said door being swingable outwardly at one side of said wall toward the open position thereof, a security lock for releasably preventing said door from swinging past a predetermined slightly open position thereof with only a narrow slot defined between said wall and the free swinging edge of said door, said door lock including a vertically elongated guide structure recessed within said floor, an elongated upstanding locking member guidingly supported from said guide structure for movement between a downwardly retracted position with the upper end thereof projecting slightly above said floor to an elevation spaced below the lower marginal edge of said door and a raised position with the upper end of said locking member projecting appreciably above said lower marginal edge, said guide structure and locking member being spaced slightly outward of said one side of said wall and in position for the lower marginal edge of said door to engage said locking member adjacent said free swinging edge when said locking member is in said raised position and said door is swung from the closed position thereof to said partially open position, said locking member being supported from said guide structure for limited oscillation relative thereto about the longitudinal center axis of said locking member between first and second latched and unlatched positions, said guide structure and locking member including first coacting means yieldingly biasing said locking member toward said raised position and second coacting means allowing said locking member to shift freely between said raised and retracted positions against the biasing action of said first coacting means when said locking member is disposed in said second position and preventing movement of said locking member from said retracted position toward said extended position when said locking member is in said first position, said vertically elongated guide structure including a hollow cylindrical sleeve member and said elongated upstanding locking member comprising a cylindrical lock bolt, said cylindrical sleeve member being fully open at its lower end and including a diametric stop pin secured transversely through its lower end portion, said first coacting means comprising a coiled compression spring disposed within said sleeve member between said stop pin and the lower end of said lock bolt, said second coacting means including a J-shaped slot formed in said sleeve member and a generally radial pin carried by said lock bolts slidingly engaged in said slot, the upper end of said locking member being roughened for increased frictional engage¬ ment with the underside of the sole of a shoe thrust downwardly upon the upper end of said locking member. 2. The security door lock of claim 1 wherein the upper end of said guide structure includes an outwardly projecting mounting flange for over¬ lying and securement to the upper surface of said floor, said mounting flange being disposed at an elevation below said lower marginal edge and the upper end of said locking member projecting slightly above said mounting flange when said locking member is in the retracted position. 3. The security door lock of claim 2 wherein said mounting flange comprises an annular mounting plate secured by welding about the upper end of said housing. OMPI •

Inventors: HOLBROOK DANA, SERRINS MAUREEN E, HOLBROOK, DANA, SERRINS, MAUREEN, E.
Applicants: PRODUCTS 4 PEOPLE INC, PRODUCTS 4 PEOPLE, INC.
Application year: 1983
Main classification: E05C5
IPC codes: E05C17