FIELD

The present disclosure relates to the field of locks. In particular, the present disclosure relates a latch and dead bolt type door lock.

DEFINITIONS

As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicate otherwise.

Jimmying a lock - The term “Jimmying a lock” hereinafter refers to forced opening of the lock.

Door jamb - The term “door jamb” hereinafter refers to a vertical portion of the door frame onto which a door is secured.

BACKGROUND

The background information herein below relates to the present disclosure but is not necessarily prior art.

Presently, a single shutter door is hinged to one of the door jambs and a lock is fitted on the inner surface of the shutter while the striker is fitted on the doorjamb. This type of locking arrangement is prone to break by jimmying, in the event of a theft attack the flanges of the lock housing and the striker get deformed. Other tools are also used to force open the door lock. This deformation in the flanges allows the thief to open the door. In a locked condition, dead bolts from the lock housing engage with the striker. The dead bolt receiving space in the striker is an open space and this space allows the dead bolts to bend towards a jamb during a theft attack. Due to this bending of the dead bolts, sufficient gap is created between the door and the jamb which allows the thief to carry out the theft.

Nowadays, different types of wooden doors are used, such as of plywood, teakwood, particle board, flush door etc. Each type of wood is of different quality and has different strength to hold the screws. While a theft is attempted, tensile force acts on the screws fitted on front face of the lock from inside of the door. So, the screws will come out in case the wood is soft or the carpenter has made the hole size bigger than required to fit the screws.

In order to overcome the aforementioned drawbacks, a reinforcement of the flanges of lock and striker is needed. Supports are required to be added at suitable locations to minimize the open space available around the dead bolt and for reducing the bending of dead bolts during a theft attempt. Also, it is important to make an arrangement to avoid screw slippage due to poor quality of the door or due to a faulty lock fitting.

There is, therefore, felt a need of a door lock that alleviates the above mentioned drawbacks.

OBJECTS Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:

An object of the present disclosure is to provide a door lock with enhanced strength.

Another object of the present disclosure is to provide a door lock which provides reinforcement to flange to enhance its strength against theft attack. Another object of the present disclosure is to provide a door lock which provides a support plate above the doorjamb to prevent dead bolts from bending.

Yet another object of the present disclosure is to provide a door lock with an anterior plate to the door which will fit on the outside of the door and can be fixed from inside with lock mounting machine screws. Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.

SUMMARY

The present disclosure envisages a door lock assembly. The door lock assembly comprises lock housing, a striker, a first reinforcement plate, and a second reinforcement plate. A lock housing flange extends along an edge of the lock housing which is closer to the doorjamb. A striker flange extends along an edge of the striker and is configured to be fastened to the door jamb. The striker flange comprises recesses defined therein. In an embodiment, a first reinforcement plate and a second reinforcement plate are fastened to the lock housing flange and the striker flange respectively. The reinforcement plates prevent jimmying of the lock assembly while a first support plate is fastened to the doorjamb surface before mounting of the striker, and a second support plate is fastened on the inside of the lock housing near the base of the lock housing flange to prevent jimmying or forced opening of the lock assembly.

In an embodiment the recesses of striker flange and recesses of the second reinforcement plate are configured to receive dead bolts when the lock assembly is in a locked state.

In an embodiment, the first reinforcement plate includes a plurality of projections that extend up to recesses in the lock housing for dead bolts in an assembled configuration.

In another embodiment, an extended portion is defined at the operative rear end of each of the dead bolts, wherein the extended portion rests on the slider.

In an embodiment, the door lock assembly includes an anterior plate provided with a plurality of internally threaded sleeves. The sleeves are perpendicular to the surface of the anterior plate and are configured to receive lock-mounting screws when the lock is being fitted on the door.

In an embodiment, the reinforcement plates are fastened to the respective flanges by welding, rivets, or screws.

In another embodiment, the first support plate is fastened to the doorjamb.

In accordance with another aspect of the invention, an anterior plate is provided for a door lock assembly. The anterior plate is configured to support the door surface in proximity to the door lock assembly and includes a plurality of sleeves that extend perpendicularly from an operative inner surface of the anterior plate. The sleeves receive lock housing mounting screws entering from the interior side of the door.

In an embodiment, the outer edges of the anterior plate are provided with curvatures to prevent entry of any tampering tool therein.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWING

The door lock assembly of the present disclosure will now be described with the help of the accompanying drawings, in which: Figure 1A, Figure IB and Figure 1C shows a side view, a front view, and a top view respectively, of the door lock assembly in door mounted condition, in accordance with an embodiment of the present disclosure;

Figure 2 shows an exploded view of the door lock assembly, in accordance with an embodiment of the present disclosure;

Figure 3 illustrates a partial cross-sectional view of the lock assembly of Figure 1, along plane P-P of Figure IB;

Figure 4A illustrates an inside view of lock housing;

Figure 4B illustrates a cross-sectional view of the lock housing of Figure 4A, along plane R- R;

Figure 5A illustrates an isometric view of the striker;

Figure 5B illustrates an isometric view of the reinforcement plate of the striker of Figure 5A;

Figure 6A illustrates an isometric view of the striker with a reinforcement plate;

Figure 6B illustrates a rear view of the striker of Figure 6A; Figure 6C shows a cross-sectional view of the striker of Figure 6B along the plane S-S;

Figure 7A illustrates an isometric view of an anterior plate of the door lock assembly, as seen from the operative front side;

Figure 7B illustrates an isometric view of the anterior plate of the door lock assembly, as seen from the operative rear side; and Figure 8 illustrates an isometric view of a support plate of a receptacle.

LIST OF REFERENCE NUMERALS USED IN DETAILED DESCRIPTION AND DRAWING

10 - Lock housing

12 - Lock housing flange 14 - Dead bolt

15 - Latch bolt

16 - Extended portion of the dead bolt 18 - Slider 20 - First reinforcement plate

20a - Projections of the first reinforcement plate 30 - Striker 32 - Striker flange 34 - Striker bridges 36 - First set of recesses

40 - Second reinforcement plate

42 - First leg portion of the second reinforcement plate

44 - Second bridges

46 - Second leg portion of the second reinforcement plate 48 - Second set of recesses

50 - Anterior plate 52 - Ribbing 60 - Sleeves

70 - Lock housing mounting screw 80 - First support plate

90 - Second support plate 100 - Door lock assembly

DETAILED DESCRIPTION

Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.

Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.

The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms “a”, “an”, and “the” may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms “comprises”, “comprising”, “including”, and “having”, are open ended transitional phrases and therefore specify the presence of stated features, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, elements, components, and/or groups thereof.

When an element is referred to as being “mounted on”, “engaged to”, “connected to”, or “coupled to” another element, it may be directly on, engaged, connected or coupled to the other element. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed elements.

The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.

Terms such as “inner”, “outer”, “beneath”, “below”, “lower”, “above”, “upper”, and the like, may be used in the present disclosure to describe relationships between different elements as depicted from the figures. In a conventional lock assembly, a door lock is mounted from the inside of the door with the help of wood screws, wherein the screws are used for wooden job work. The fitment offered by these screws is different for different wood materials. For example, a lock fitment in teakwood door offer more strength as compared to that fitted in a particle board door. Also, the quality and the strength of fitment depend on the skill of the carpenter. In case, the carpenter has made a hole bigger than the required size, the screw fitment remains loose. Sometimes, the carpenter uses a hammer to fit the screws instead of using a screw driver. In both these cases, the screws can be easily removed when subjected to a pull load by any unauthorised person or a thief.

In the event of a burglary, tensile load acts on the top screws of the lock. As a result of this tensile load, the screws get easily removed, considering a wrong fitment as mentioned above, and thus the lock housing can be removed from the door to allow the thief to enter the house.

In the conventional lock assembly, the quality of lock fitment depends on various field parameters such as: door material, door jamb material, and the carpenter’s skill. During a theft attempt, the robber applies the load on the door lock using a crow bar. As a result of this load, dead bolts from the lock housing tend to bend towards a flange of the lock housing. These dead bolts due to their bending action apply load on the flange of the lock housing. The flange initially restricts the bending, but beyond a certain load the flange starts deforming and allows further bending of the dead bolts. This load acts on bridges between recesses of the striker and the bridges start to deform. The bridges deform up to a certain limit and eventually they get sheared. This type of deformation in the flange happens when the lock housing is of a single layered sheet metal.

The door lock assembly 100 of the present disclosure will now be described with the help of Figure 1A through Figure 8.

The door lock assembly 100 comprises a lock housing 10, a lock housing flange 12, at least one dead bolt 14, a latch bolt 15, a slider 18, a first reinforcement plate 20, a striker 30, a striker flange 32, striker bridges 34, a second reinforcement plate 40, an anterior plate 50, and a plurality of sleeves 60, a first support plate 80 placed on the door jamb, and a second support plate 90 fastened to the lock housing 10. An extended portion 16 is defined at the operative rear side of the dead bolt 14. The sleeves 60 are internally threaded and project from the surface of the anterior plate 50. The sleeves 60 are configured to receive fastening screws when the lock assembly 100 is being fitted on the door.

Figures 1A, IB, and 1C illustrate a door lock assembly 100 of the present disclosure, wherein the lock housing 10 is mounted on the door from inside while the anterior plate 50 is mounted from outside of the door. The striker 30 is mounted in the doorjamb.

The striker 30 is configured to receive the dead bolts 14 & latch bolt 15 projecting from the lock housing 10. The striker 30 comprises a striker flange 32 extending from the edge which is in co-operation with the door jamb. A first set of recesses 36 is incorporated on a striker flange 32, while a second set of recesses 48 is configured on a second reinforcement plate 40. The first set of recesses 36 and the second set of recesses 48 are configured to receive the dead bolts 14 and latch bolt 15 (optional) projecting from the lock housing 10, when the lock assembly 100 is in a locked state or the door is closed.

The lock assembly 100, as disclosed in the present disclosure, has a configuration that makes it sturdier against a theft attack. The lock assembly 100 of the present disclosure is not susceptible to failure even under the application of high load associated with theft scenarios.

Figure 1A to Figure 1C illustrate different views of the lock assembly 100 in accordance with an embodiment of the present disclosure. The lock housing flange 12 extends from one edge of the lock housing 10. The lock housing 10 is configured to be embedded on door and supports the reciprocating dead bolts 14 and the latch bolt 15. The reciprocating dead bolts 14 and latch bolt 15 are received in the first set of recesses 36 when the lock assembly 100 is in a locked state. In an embodiment, the lock assembly 100 may have only dead bolt 14 and no latch bolt 15. The lock housing 10 further comprises a first reinforcement plate 20. The first reinforcement plate 20 is fastened to the lock housing flange 12 with suitable means so as to become an integral part of the lock housing flange 12.

The first reinforcement plate 20 provides additional support to the dead bolts 14 and prevents them from bending during a theft attack. The first reinforcement plate 20 partially shares the bending load acting on the lock housing flange 12 and protects the house or premises against theft. Figure 3 illustrates a cross-sectional view of the lock assembly of Figure 1, along plane P-P. The dead bolts 14 are fixed on a slider 18, wherein the slider 18 is configured to reciprocate inside the lock housing 10. The extended portion 16 of the dead bolt 14 rests on the surface of the slider 18 of the bolt assembly. During a theft event, this extended portion 16 constrains the bending action of the dead bolt 14 by resting on the surface of the slider 18.

Figure 4A illustrates an inside view of lock housing 10 while Figure 4B illustrates a cross- sectional view of the lock housing 10 of Figure 4A along plane R-R. The second support plate 90 is configured in the lock housing 10 as shown in Figure 3 and Figure 4A. During a theft attempt, the second support plate 90 supports the dead bolts 14 and latch bolts 15 to prevent the bending of the dead bolts and latch bolt.

Figure 5A illustrates an isometric view of the striker 30 while Figure 5B illustrates an isometric view of the second reinforcement plate 40. A plurality of identical through holes is defined in both the striker 30 and the second reinforcement plate 40 to facilitate fastening to each other. The second reinforcement plate 40 is fastened to the striker 30 from the inner side of the striker 30. Screws or rivets are used to fasten the striker 30 and the second reinforcement plate 40.

In another embodiment, the first reinforcement plate 20 includes a plurality of projections 20a that extend up to the recesses formed in the lock housing 10 for dead bolts 14, when in an assembled configuration.

Figure 6A illustrates an isometric view of the assembly of the striker 30 and the second reinforcement plate 40, which shows the second reinforcement plate 40 that is fastened to the striker flange 32. During a theft attack, the bending load of the dead bolts 14 acting on the striker bridges 34 is shared by a set of second bridges 44 defined in the second reinforcement plate 40.

In an embodiment, the second reinforcement plate 40 of the striker 30 further comprises a longer first leg portion 42 and a shorter second leg portion 46 provided at the operative bottom edge of the second reinforcement plate 40. During a theft attack the second leg portion 46 of the second reinforcement plate 40 supports the dead bolts 14 from the operative inner side of striker of the lock assembly 100 and reduces the deformation in striker 30 and prevents the shearing of the bridges 34. Figure 7 A and Figure 7B illustrate isometric views of the anterior plate 50 which will fit on outside of the door. Two threaded sleeves 60 are incorporated on the anterior plate 50 on its inner face.

The outer edges of the anterior plate 50 are provided with curvature to prevent entry of any tampering tool therein.

According to another aspect of the invention the anterior plate 50 can be used with any type of lock assembly. The anterior plate 50 provides sufficient strength to the door surface.

Heavy ribbing 52 is provided on the outer edge of the anterior plate 50, which strengthens the anterior plate 50 and prevents it from bending. While the lock assembly 100 is being fitted to the door, the anterior plate 50 will fit on the outer surface of the door and the lock housing 10 from the inner surface of the door, such that lock housing mounting screws 70 will enter from the lock housing and engage with the threaded sleeves 60. The sleeves 60 pass through a considerable door thickness in an assembled condition so that during a theft attempt, anterior plate 50 along with the lock housing mounting screws 70 will not get pulled out easily.

Figure 8 illustrates isometric view of the first support plate 80 which will fit on the surface of door jamb as shown in Figure 3. In dead bolt locking condition, the first support plate 80 occupies a space between the dead bolt 14 and the inner surface of the pocket of the door jamb, such that during a theft attack when the dead bolt 14 in being bent, the first support plate 80 gives support to the dead bolt 14 and avoids any further bending of the dead bolts 14. This helps in avoiding theft.

The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.

TECHNICAL ADVANCES AND ECONOMICAL SIGNIFICANCE The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a door lock assembly that:

• is reliable;

• is of sufficient strength;

• avoids jimmying; and

• avoids any forceful and unauthorized opening of the door lock.

The foregoing description of the specific embodiments so fully reveals the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, or group of elements, but not the exclusion of any other element, or group of elements.

The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.

While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.