Gard-U door safety system

Abstract

A sliding latch replaces a prior art door strike plate. The sliding latch has two components, a strike plate and a sliding latch cover reciprocal within the strike plate. A handle protrudes from the sliding latch cover sufficiently to extend beyond a closed door and door frame, to permit the handle to be manually grasped and lifted in a crisis. When the sliding latch cover is thus elevated, it no longer blocks the door bolt, allowing the bolt to extend farther and engage with the strike plate and extend into the door jamb, locking the door. One of the strike plate mounting screw holes is preferably drawn slightly out of the primary plane of the strike plate toward the jamb, and a pair of elevated distally located edges run longitudinally along the strike plate. The drawn screw hole and raised edges guide and limit motion of the sliding latch cover.

Claims

1. In combination, a door and a sliding latch, said door comprising: a door jamb; a door movably affixed to said door jamb between a first closed position and a second open position; and an extendible and retractable bolt supported in said door and having a first extended position configured to extend into said door jamb when said door is closed and a second retracted position configured to retract into said door; said sliding latch comprising: a strike plate having a generally planar body member, a bolt hole aligned and operative with said extendible and retractable bolt to lock said door when said door is closed and said extendible and retractable bolt is in said extended position, and a pair of raised distally located edges; a sliding latch cover reciprocally contained within said strike plate between said pair of raised distally located edges and configured to reciprocate along a first axis between a first unlocked position configured to prevent said extendible and retractable bolt from reaching said first extended position and a second locked position displaced from said first position configured to allow said extendible and retractable bolt to reach said first extended position and thereby lock said door; and a handle arm extending transversely to said sliding latch cover and configured to protrude from said door jamb and said door when said door is in said first closed position; wherein said strike plate further comprises at least one fastener hole defined by a perimeter protruding out of said generally planar body member in a direction toward said door jamb.

2. The combination door and sliding latch of claim 1, wherein said strike plate is affixed to said door jamb.

3. The combination door and sliding latch of claim 1, wherein said sliding latch further comprises a slide guide opening having upper and lower terminations and defining a longitudinally extensive slot therebetween, said at least one fastener hole perimeter passing at least partially into said slide guide opening.

4. The combination door and sliding latch of claim 3, wherein said sliding latch cover first unlocked position comprises said at least one fastener hole perimeter engaged with said upper termination.

5. The combination door and sliding latch of claim 4, wherein said sliding latch cover second locked position comprises said at least one fastener hole perimeter engaged with said lower termination.

6. The combination door and sliding latch of claim 1, wherein said handle arm is unitary with said sliding latch cover and in combination therewith defines a generally planar body having an L shaped outline.

7. The combination door and sliding latch of claim 3, wherein said at least one fastener hole further comprises a first fastener hole adjacent to an upper longitudinal end of said strike plate.

8. The combination door and sliding latch of claim 7, wherein said at least one fastener hole further comprises a second fastener hole adjacent to a lower longitudinal end of said strike plate, said second fastener hole distal to said first fastener hole.

9. In combination, a door and a sliding latch, said door comprising: a door jamb; a door movably affixed to said door jamb between a first closed position and a second open position; and an extendible and retractable bolt supported in said door and having a first extended position configured to extend into said door jamb when said door is closed and a second retracted position configured to retract into said door; said sliding latch comprising: a strike plate affixed to said door jamb, said strike plate having a generally planar body member, a bolt hole aligned and operative with said extendible and retractable bolt to lock said door when said door is closed and said extendible and retractable bolt is in said extended position, and at least one fastener hole defined by a perimeter protruding out of said generally planar body member in a direction toward said doorjamb; and a sliding latch cover having a striker surface, and a slide guide opening having upper and lower terminations and defining a longitudinally extensive slot therebetween, said at least one fastener hole perimeter passing at least partially into said slide guide opening, said sliding latch cover reciprocally contained within said strike plate and configured to reciprocate along a first axis between a first unlocked position with said at least one fastener hole perimeter engaged with said upper termination and configured in said first unlocked position to prevent said extendible and retractable bolt from reaching said first extended position and a second locked position displaced from said first position with said at least one fastener hole perimeter engaged with said lower termination and configured to allow said extendible and retractable bolt to reach said first extended position and thereby lock said door.

10. The combination door and sliding latch of claim 9, wherein said sliding latch further comprises a handle arm extending transversely to said sliding latch cover, said handle arm configured to protrude from said door jamb and said door when said door is in said first closed position.

11. The combination door and sliding latch of claim 10, wherein said handle arm is unitary with said sliding latch cover and in combination therewith defines a generally planar body having an L shaped outline.

12. The combination door and sliding latch of claim 9, wherein said at least one fastener hole further comprises a first fastener hole adjacent to an upper longitudinal end of said strike plate.

13. The combination door and sliding latch of claim 12, wherein said at least one fastener hole further comprises a second fastener hole adjacent to a lower longitudinal end of said strike plate, said second fastener hole distal to said first fastener hole.

14. The combination door and sliding latch of claim 9, wherein said strike plate further comprises a pair of raised distally located edges, said sliding latch cover reciprocally contained within said strike plate between said pair of raised distally located edges.

15. A sliding latch, comprising: a strike plate configured to be affixed to a door jamb, said strike plate having a generally planar body member, a bolt hole configured to align with an extendible and retractable bolt and to thereby lock a door when said door is closed and said extendible and retractable bolt is in an extended position, and at least one fastener hole defined by a perimeter protruding out of said generally planar body member in a direction configured to extend toward said door jamb; and a sliding latch cover having a striker surface, and a slide guide opening having upper and lower terminations and defining a longitudinally extensive slot therebetween, said at least one fastener hole perimeter passing at least partially into said slide guide opening, said sliding latch cover reciprocally contained within said strike plate and configured to reciprocate along a first axis between a first unlocked position with said at least one fastener hole perimeter engaged with said upper termination and configured in said first unlocked position to prevent said extendible and retractable bolt from reaching said extended position and a second locked position displaced from said first position with said at least one fastener hole perimeter engaged with said lower termination and configured to allow said extendible and retractable bolt to reach said extended position and thereby lock said door.

16. The sliding latch of claim 15, wherein said sliding latch further comprises a handle arm unitary with and extending transversely to said sliding latch cover and in combination with said sliding latch cover defining a generally planar body having an L shaped outline, said handle arm configured to protrude from said door jamb and said door when said door is closed.

17. The sliding latch of claim 15, wherein said at least one fastener hole further comprises a first fastener hole adjacent to an upper longitudinal end of said strike plate.

18. The sliding latch of claim 17, wherein said at least one fastener hole further comprises a second fastener hole adjacent to a lower longitudinal end of said strike plate, said second fastener hole distal to said first fastener hole.

19. The sliding latch of claim 15, wherein said strike plate further comprises a pair of raised distally located edges, said sliding latch cover reciprocally contained within said strike plate between said pair of raised distally located edges.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The foregoing and other objects, advantages, and novel features of the present invention can be understood and appreciated by reference to the following detailed description of the invention, taken in conjunction with the accompanying drawings, in which:

(2) FIGS. 1-4 illustrate a first preferred embodiment Gard-U Door Safety System designed in accord with the teachings of the present invention from a front elevational view with the slide in an upmost position of travel, a back elevational view with the slide in a middle position of travel, a back elevational view with the slide in a bottom position of travel, and a top plan view, respectively.

(3) FIG. 5 illustrates the first preferred embodiment Gard-U Door Safety System of FIGS. 1-4 from a sectional view taken along section line 5 in FIG. 2.

(4) FIGS. 6-9 illustrate a first alternative embodiment Gard-U Door Safety System designed in accord with the teachings of the present invention from a front elevational view with the slide in an upmost position of travel, a back elevational view with the slide in a middle position of travel, a back elevational view with the slide in a bottom position of travel, and a top plan view, respectively.

DESCRIPTION OF THE PREFERRED EMBODIMENT

(5) Manifested in the preferred and alternative embodiments, the present invention provides a sliding latch that affixes to a door frame as a replacement for the existing strike plate, that can be installed using a screwdriver, and that is readily operated to switch a door from an unlocked state to a locked state in a crisis by nearly all persons.

(6) In a first preferred embodiment of the invention illustrated in FIGS. 1-5, a sliding latch 1 is comprised of only two components: a strike plate 10, and sliding latch cover 20 that reciprocates within strike plate 10. Strike plate 10 has a body member 11 through which a pair of screw holes 12, 13 and a bolt and latch bolt hole 14 are formed. This general geometry is preferably very similar in the front elevational view outline of FIG. 1 to that of prior art strike plates, to ensure the compatibility of first preferred embodiment sliding latch 1 with nearly all doors. However, as best illustrated in FIG. 4, a pair of raised edges 15 border the body member 11, creating a small gap between body member 11 and prior art door jamb 2 when installed. It is within this small gap that sliding latch cover 20 will reciprocate.

(7) Sliding latch cover 20 has a striker surface 21, a handle arm 22, and a slide guide opening 23 formed in striker surface 21. The arrow 25 in FIGS. 1-3 illustrates the direction of travel available for sliding latch cover 20 in each of the illustrated positions.

(8) In the position illustrated in FIG. 1, sliding latch cover 20 is shifted to a most elevated extreme position of travel with respect to strike plate 10. Raised edges 15 contain the longitudinally extensive edges of strike surface 21 to ensure that sliding latch cover 20 reciprocates in a linear manner. Preferably, screw hole 12 is not a simple hole, but is gently countersunk as visible in FIGS. 2 and 3 and well illustrated in FIG. 5. Consequently, screw hole 12 has material protruding toward door jamb 2, thereby defining a protrusion that is loosely engaged within the vertical edges of slide guide opening 23. Since screw hole 12 protrudes into the thickness of sliding latch cover 20, this screw hole also helps to urge sliding latch cover 20 to slide in a linear direction of travel. However, this linear travel is not the sole or even primary function for the protrusion of screw hole 12. Instead, and as may be ascertained from FIG. 1, the sliding latch cover 20 most elevated extreme position relative to strike plate 10 is determined by the lower or bottom-most end of slide guide opening 23 engaging with the protrusion of screw hole 12. While it would be conceivable to instead allow a screw inserted through screw hole 12 to limit travel, this would over time likely lead to damage of both the screw and sliding latch cover 20. Therefore, but much less preferably, in one alternative embodiment where screw hole 12 does not protrude a sleeve will be provided about the screw shaft to prevent direct contact between the threads on the screw shaft and the lower or bottom-most end of slide guide opening 23. In a second alternative embodiment, the screw will be a shoulder screw, having an unthreaded shoulder adjacent to the screw head which slide guide opening 23 could contact at the upper limit of travel.

(9) The sliding latch cover 20 lower or bottom-most extreme position relative to strike plate 10 such as illustrated in FIG. 3 is similarly determined by the engagement of screw hole 12 with the upper or top-most end of slide guide opening 23. In this position, a lower portion of the bolt and latch bolt hole 14 is completely blocked that was open in FIG. 1. In addition, the size of the slide guide opening 23 as measured between vertical edges is significantly smaller than the size of the bolt and latch bolt hole 14 also measured between vertical edges. Consequently, most prior art bolts are too large to fit through slide guide opening 23. This means that in most cases it will not matter where the locking bolt will pass through bolt and latch bolt hole 14, it will be blocked by sliding latch cover 20 when sliding latch cover 20 is in the position illustrated in FIG. 3.

(10) As may be appreciated, if there is a large enough gap between body member 11 and door jamb 2 created by raised edges 15, then sliding latch cover 20 will always drop down to the position of FIG. 3, which is the latch blocking position. The protrusion of screw hole 12 toward jamb 2 ensures that even if an installer were to excessively tighten the screw, it cannot collapse the gap.

(11) This gap between body member 11 and door jamb 2 means that as soon as a latched door is opened, sliding latch cover 20 will drop into the position of FIG. 3, and the door will then not be able to latch upon closing. However, a simple grasp of handle arm 22 followed by raising will permit the spring mechanism of a latch bolt to push the latch bolt through bolt and latch hole 14. If the latch bolt is a locking latch bolt, then this simple raising of sliding latch cover 20 will instantly lock the door, but until then the door will remain in an unlatched state even when closed.

(12) The particular geometry of handle arm 22 may be varied from the L shape the handle forms with the balance of sliding latch cover 20. Nevertheless, it is preferable that handle arm 22 be co-planar with the balance of sliding latch cover 20, which permits sliding latch cover 20 to be installed so that handle arm 22 is facing either to the left as illustrated in FIG. 1, or if sliding latch cover 20 is flipped left-to-right, so that handle arm 22 is facing to the right. This allows preferred embodiment sliding latch 1 to be installed on either left or right-handed doors that open inward into a lock-securable space, without requiring a change to the hardware purchased. Furthermore, most preferably handle arm 22 is designed to extend transversely to the longitudinal (vertical) axis of striker surface 21 sufficiently that it extends beyond the door frame and closed door sufficiently to be readily grasped and lifted by a person in a crisis. In the event a door opens out rather than in, handle arm 22 may be bent either at the factory or on-site just prior to installation to the shape required to pass around the door frame and between the door frame and door.

(13) While the foregoing operations describe an automatic blocking function provided by sliding latch cover 20 sliding within the gap created by raised edges 15, selective blocking may be achieved by providing a smaller protrusion of screw hole 12 toward door jamb 2 that is operative, when the screw is tightened, to very gently collapse body member 11 into contact with and apply pressure to striker surface 21. This will create a controlled amount of friction therebetween, which if so desired in an alternative embodiment can be used to allow a person to set the position of sliding latch cover 20 relative to strike plate 10, with reasonable expectation that it will stay where set. In this alternative embodiment, a person must more actively set the position of sliding latch cover 20, to either open access to bolt and latch bolt hole 14, or to restrict access thereto.

(14) The description herein above about first preferred embodiment sliding latch 1 refers to the attachment of strike plate 10 to a prior art door jamb 2. In an alternative embodiment, strike plate 10 is instead affixed to the edge of the door, and sliding latch cover 20 is then used to selectively either block the locking bolt or provide an opening for the locking bolt to pass through.

(15) Latch apparatus including strike plate 10 and sliding latch cover 20 designed in accord with the teachings of the present invention may be manufactured from a variety of materials, including metals, resins and plastics, ceramics or cementitious materials, or even combinations, laminations, or composites of the above. Owing to the low cost, ready fabrication, physical strength and durability, resistance to galling and fatiguing, for many applications steel or stainless steel may be used. Noteworthy here is that by using a metal, and with the geometry illustrated and preferred, both of the strike plate 10 and sliding latch cover 20 may readily be stamped from sheet or roll stock at very low production cost. Additionally, where desired various coatings or laminates of different materials may optionally be provided, such as a slippery plastic coating to facilitate the sliding latch cover 20 sliding quietly, or an anti-corrosion coating or plating such as zinc to protect a lower cost base metal such as steel from corrosion.

(16) Several preferred embodiments of latch apparatus designed in accord with the present invention have been illustrated in the various figures. The embodiments are distinguished by the hundreds digit, and various components within each embodiment designated by the ones and tens digits. However, many of the components are alike or similar between embodiments, so numbering of the ones and tens digits have been maintained wherever possible, such that identical, like or similar functions may more readily be identified between the embodiments. If not otherwise expressed, those skilled in the art will readily recognize the similarities and understand that in many cases like numbered ones and tens digit components may be substituted from one embodiment to another in accord with the present teachings, or where parts are not expressly numbered, except where such substitution would otherwise destroy operation of the embodiment. Consequently, those skilled in the art will readily determine the function and operation of many of the components illustrated herein without unnecessary additional description.

(17) In a first alternative embodiment Gard-U Door Safety System illustrated in FIGS. 6-9, a sliding latch 101 is comprised of a strike plate 110, and sliding latch cover 120 that reciprocates within strike plate 10. As noted, strike plate 110 and sliding latch cover 120 resemble their counterparts found in sliding latch 1. Nevertheless, sliding latch cover 120 differs in two notable ways. First, slide guide protrusion 124 is formed on the lower end of striker surface 121, distal to handle arm 122. In addition, handle arm 122 in this alternative embodiment is not co-planar with striker surface 121.

(18) In the position illustrated in FIG. 6, sliding latch cover 120 is shifted to a most elevated extreme position of travel with respect to strike plate 110. Raised edges 115 ensure that sliding latch cover 120 reciprocates in a linear manner. In addition, slide guide protrusion 124 is displaced into an approximately co-planar relationship with body member 111, and so loosely engages with the vertical sides of bolt and latch bolt hole 114. Since screw hole 112 protrudes into the thickness of sliding latch cover 120, and since slide guide protrusion 124 protrudes into the thickness of body member 111, there are two linearly displaced points of engagement that are operative to also urge sliding latch cover 120 to slide in a linear direction of travel. However, this linear travel is not the sole or even primary function for the protrusion of screw hole 112 and slide guide protrusion 124. Instead, and as may be ascertained from FIG. 6, the sliding latch cover 120 most elevated extreme position relative to strike plate 110 is determined by the lower or bottom-most end of slide guide opening 123 engaging with the protrusion of screw hole 112. While it would be conceivable to instead allow a screw inserted through screw hole 112 to limit travel, this would over time likely lead to damage of both the screw and sliding latch cover 120. Therefore, but much less preferably, in one alternative embodiment where screw hole 112 does not protrude a sleeve will be provided about the screw shaft to prevent direct contact between the threads on the screw shaft and the lower or bottom-most end of slide guide opening 123. In a second alternative embodiment, the screw will be a shoulder screw, having an unthreaded shoulder adjacent to the screw head which slide guide opening 123 could contact at the upper limit of travel.

(19) The sliding latch cover 120 lower or bottom-most extreme position relative to strike plate 110 such as illustrated in FIG. 8 is determined by the engagement of slide guide protrusion 124 with the lower or bottom-most end of bolt and latch bolt hole 114. In this position, a vertical portion of the bolt and latch bolt hole 114 is completely blocked that was open in FIG. 1.

(20) As aforementioned, the geometry of handle arm 122 differs from that of handle arm 22. In those instances where reversibility between left and right hand doors, handle arm 122 may be bent out of co-planar relationship with striker surface 121, and away from the door opening. As visible in FIG. 9, in this first alternative embodiment sliding latch 101 the handle arm 122 is curved away from the door opening at any suitable angle.

(21) While the foregoing details what is felt to be the preferred embodiment of the invention, no material limitations to the scope of the claimed invention are intended. Further, features and design alternatives that would be obvious to one of ordinary skill in the art are considered to be incorporated herein. The scope of the invention is set forth and particularly described in the claims herein below.