WO2024161190A1

WO2024161190A1 - A lock assembly for drawer and cabinet door

Info

Publication number: WO2024161190A1
Application number: PCT/IB2023/052699
Authority: WO
Inventors: Prabhakar Anant JOSHI; Salil Prabhakar JOSHI
Original assignee: Joshi Prabhakar Anant; Joshi Salil Prabhakar
Priority date: 2023-02-02
Filing date: 2023-03-20
Publication date: 2024-08-08

Abstract

The present disclosure discloses a lock assembly (1000) for drawer and cabinet door. The lock assembly has a case (10) configured to be mounted on a surface of the cabinet, a housing (40) configured on the cover plate (20), and a lock cylinder (50) configured to be rotatably driven within the housing. The lock cylinder is coupled to a bolt (30). The lock assembly comprises a plurality of wafer plates (60) configured inside slots on the lock cylinder. Each wafer plate has an opening (63) configured for allowing passage of a key (90) having unique configuration of dimples (91). A plurality of lugs (61) is defined on the wafer plates. The lugs are configured to be in one to one correspondence with the dimples. When the proper key is angularly displaced, the angular motion of the key displaces the bolt for locking the door.

Description

A LOCK ASSEMBLY FOR DRAWER AND CABINET DOOR FIELD The present disclosure relates to a lock assembly for securing drawer and cabinet of furniture. DEFINITION 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. Wafer plate – The term ‘wafer plate’ refers to lock levers in the form of thin plates that have profiles corresponding to a profile configured on a lock key, such that the profile of the key contacts the profile of the wafer plate during operation of the lock assembly, for attaining a locked configuration or an unlocked configuration of the lock assembly. BACKGROUND The background information herein below relates to the present disclosure. In a conventional lock assembly, a key having notches is used to rotate a lock cylinder. The lock cylinder is coupled to a bolt which slides in the slot provided on the frame of a cabinet or a drawer to attain a locked configuration. The key having notches and serrations when inserted through a key hole mates with a plurality of wafer plates. However, contact of the notches with the wafer plates on the key results in increased friction during operation of the key. This makes the locking operation noisy and difficult as excess amount of energy is required to operate the lock assembly. Moreover, the number of key-combinations obtained by the notched key are less. This makes the conventional lock assembly prone to duplication, as an ordinary key maker can easily manufacture the notched keys by traditional machining process. Thus, the conventional lock assembly is prone to misuse that jeopardises the security of the articles stored in the drawer or the cabinet. Therefore, there is a need of a lock assembly for drawer and cabinet door that alleviates the aforementioned 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 invention is to provide a lock assembly for drawer and cabinet door. Another object of the present invention is to provide a lock assembly for drawer and cabinet door, which is suitable for doors having minimum panel thickness. Still another object of the present invention is to provide a lock assembly for drawer and cabinet door, which has a robust housing. Yet another object of the present invention is to provide a lock assembly for drawer and cabinet door, that is easy to use and provide smooth locking and unlocking function. Still another object of the present invention is to provide a lock assembly for drawer and cabinet door, that provides improved security. Yet another object of the present invention is to provide a lock assembly for drawer and cabinet door, that is easy to manufacture and assemble. Still another object of the present invention is to provide a lock assembly for drawer and cabinet door, with minimum weight and dimension. Yet another object of the present invention is to provide a lock assembly for drawer and cabinet door, which is aesthetically appealing to the user. 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 discloses a lock assembly for drawer and cabinet door. The lock assembly has a case configured to be mounted on a surface of the drawer or cabinet, a housing configured on the cover plate, and a lock cylinder configured to be rotatably driven within the housing. The lock cylinder is coupled to a bolt of the lock assembly. The lock assembly comprises a plurality of wafer plates configured to be positioned inside slots provided on the lock cylinder. Each of the plurality of wafer plates has an opening configured thereon for allowing passage of a key having a unique configuration of dimples. A unique configuration of a plurality of lugs is defined on the plurality of wafer plates. The lugs are configured to be in one to one correspondence with the dimples on the key. In an operative configuration, when the proper key is inserted into a key slot and the key is angularly displaced, the dimple configuration on the key matches with the lug configuration on the wafer plates, to thereby transfer the angular motion of the key to the bolt for locking and unlocking of the door. In an embodiment, the bolt is linearly displaced due to the angular displacement of the key having dimples, to attain an operative locked configuration and an operative unlocked configuration of the lock assembly. In an embodiment, the lock cylinder is configured with a lever, the lever is secured in a groove of the bolt to displace the bolt and attain the operative locked configuration and the operative unlocked configuration of the lock assembly. In an embodiment, the lock cylinder is oriented co-axial with respect to the housing. In an embodiment, a cover plate is configured within the case, the cover plate is configured to secure the housing. In a preferred embodiment, each of the lugs has a distinct sizes corresponding to the depth of each of the dimples on the key. In a preferred embodiment, the wafer plates have a plurality of lugs, and the lugs are configured to mate with an array of dimples configured on the key. In a preferred embodiment, the lugs lie offset to the wafer plates in an operative longitudinal direction in bent wafer plate. In a preferred embodiment, the opening is configured in an operative central portion of the wafer plates for allowing passage of a key having dimples. In another embodiment, at least one of the wafer plates is configured with the lug. In yet another embodiment, at least one of the wafer plates is configured with a plurality of the lugs. In another embodiment, the construction profile of the wafer plate is a bent wafer plate having a bent type lug. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING A lock assembly of drawer and cabinet door, of the present disclosure, will now be described with the help of the accompanying drawings, in which: Figure 1 illustrates an exploded view of the lock assembly of the prior art; Figure 2A illustrates a front view of a wafer type key of the prior art; Figure 2B illustrates a top view of the Figure 2A; Figure 2C illustrates a view showing the serration of the key in a mated condition with the slot on the wafer plate, of the prior art; Figure 3A illustrates a front view of the lock assembly of the present disclosure; Figure 3B illustrates a top view of the lock assembly of the Figure 3A; Figure 3C illustrates a bottom view of the lock assembly of the Figure 3A; Figure 4A illustrates an exploded view of the lock assembly having a flat wafer plate construction, in accordance with a first embodiment of the present disclosure; Figure 4B illustrates an exploded view of the lock assembly having a bent wafer plate construction, in accordance with a second embodiment of the present disclosure; Figure 5A illustrates a front view of the lock assembly with the flat type wafer plate in a locked condition; Figure 5B illustrates a cross-sectional view of the lock assembly along plane P-P of Figure 5A; Figure 5C illustrates a front view of the lock assembly with the flat type wafer plate in an unlocked condition; Figure 5D illustrates a cross-sectional view of the lock assembly along plane Q-Q of Figure 5C; Figure 6A illustrates a front view of the lock assembly with the bent type wafer plate in a locked condition; Figure 6B illustrates a cross-sectional view of the lock assembly along plane P-P of Figure 6A; Figure 6C illustrates a front view of the lock assembly with the bent type wafer plate in an unlocked condition; Figure 6D illustrates a cross-sectional view of the lock assembly along plane Q-Q of Figure 6C; Figure 7 illustrates a view of the lock assembly in the locked configuration with the bolt in a limiting position; Figure 8 illustrates a view of the lock assembly in the mid position of the locked configuration with the bolt in an intermediate position; Figure 9 illustrates a view of the lock assembly in the unlocked configuration with the bolt in another limiting position; Figure 10A illustrates a front view of the case; Figure 10B illustrates a side view of the Figure 10A; Figure 10C illustrates another side view of the case of the Figure 10A; Figure 11A illustrates a front view of the cover plate; Figure 11B illustrates a bottom view of the Figure 11A; Figure 11C illustrates a side view of the cover plate of Figure 11A; Figure 12A illustrates a front view of the dead bolt; Figure 12B illustrates a top view of the Figure 12A; Figure 13A illustrates a front view of the housing; Figure 13B illustrates a cross-sectional view of the housing along a plane P-P of the Figure 13A; Figure 13C illustrates a cross-sectional view of the housing along a plane Q-Q of Figure 13A; Figure 14A illustrates a front view of the cylinder with the flat type wafer plate; Figure 14B illustrates a top view of the Figure 14A; Figure 14C illustrates a cross-sectional view of the cylinder along plane P-P of Figure 14A; Figure 15A illustrates a front view of the cylinder with the bent type wafer plate; Figure 15B illustrates a top view of the Figure 15A; Figure 15C illustrates a cross-sectional view of the cylinder along plane Q-Q of Figure 15A; Figure 16A illustrates a front view of the flat type wafer plate; Figure 16B illustrates a top view of Figure 16A; Figure 16C illustrates a side view of flat type wafer plate of Figure 16A; Figure 17A illustrates a front view of bent type wafer plate; Figure 17B illustrates a top view of Figure 17A; Figure 17C illustrates a side view of bent type wafer plate of Figure 17A; Figure 18 illustrates a front view of the clip plate; Figure 19A illustrates a front view of the dimple key; Figure 19B illustrates a top view of Figure 19A; Figure 20A illustrates a 3D view showing the dimple on the key in a mated condition with the lug on the flat wafer plate; and Figure 20B illustrates a 3D view showing the dimple on the key in a mated condition with the lug on the bent wafer plate. LIST OF REFERENCE NUMERALS 10 – case 11, 13, 14, 21, 22, 23, 26, 72, 92 – aperture 12, 24, 62, 62A, 71 – projections 20 – cover plate 25 – snap fit element 30 – bolt 31 – groove 40 – housing 41 – locators 42 – first step 43 – second step 44 – third step 45 – fourth step 50, 50A – cylinder 51, 51A, 63, 63A – opening 52, 52A, 53, 53A, 54, 55, 55A, 56, 56A – slot 55 – Slot for flat wafer plate spring 57, 57A – lever 58, 58A – stopper 60 – wafer plate 60A – bent wafer plate 61 – lug 61A – bent type lug 64 – compression spring 70 – clip plate 80 – indexing ball 81 – Indexing spring 90 – key 91 – array of dimples 1000, 2000 – lock assembly L – operative longitudinal direction X – operative transverse plane 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. The particular order of steps disclosed in the method and process of the present disclosure is not to be constructed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed. 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. Referring to figures 1, 2A, 2B and 2C a conventional lock assembly 1000’ will now be described. Typically, drawers and cabinets are generally a single shutter with hinge at one side or double shutter or a sliding door for a cabinet. The Figure 1 illustrates an exploded view of a conventional lock assembly 1000’ consisting of a lock cylinder 50’. The Figure 2A illustrates a front view of a wafer type key 90’ used in conventional lock assembly 1000’ and Figure 2B illustrates a top view of the Figure 2A. In wafer type key 90’, friction between the key 90’ and the wafer plates 60’ is more due to more area of contact, as shown in the Figure 2C. So, friction is experienced during the key 90’ insertion and removal operation. In the wafer type key 90’, the key 90’ with notches are used which has serration on one edge of flat face. this type of key 90’ is manufactured by conventional machining process. The number of the key 90’ combinations is very less in this type of the key 90’. So, it is very easy to duplicate by ordinary key maker and security is very less. Also, in wafer type key probability of wafer plate bending is more during key insertion and withdrawal operation. So, in that case the key 90’ gets stuck in the cylinder 50’and the lock function gets disabled. Thereby, the conventional lock assembly 1000’ is not safe and secure enough for drawers or cabinets. To overcome the aforementioned drawbacks, the present disclosure envisages a lock assembly for drawers and cabinets. The lock assembly 1000, 2000 of the present invention will now be described with respect to figures 3A-20B. The lock assembly 1000, 2000 is configured to be mounted on an operative surface of a drawer and a cabinet door. A first embodiment of the present disclosure will now be described with reference to the Figure 3A, Figure 3B, Figure 3C, Figure 4A, Figure 5A, Figure 5B, Figure 5C, Figure 5D, Figures 7-14C, Figure 16A-16C, Figure 18, Figure 19A, Figure 19B and Figure 20A. The lock assembly 1000, 2000 includes a housing 40, a cylinder 50, 50A, a lever 57, 57A, a bolt 30, a case 10 and a cover plate 20. The lock assembly 1000, 2000 comprises a plurality of wafer plates 60, 60A configured to be positioned on the cylinder 50, 50A, and a lug 61, 61A defined on each of the plurality of wafer plates 60, 60A. The lugs 61, 61A are configured to transfer angular displacement of the key 90 to linear displacement of the bolt 30 for locking and unlocking the drawer and cabinet door panel with respect to the frame of the drawer and cabinet. A unique combination of the lugs 61, 61A is defined on the wafer plates 60, 60A. More particularly, the dimensions of the lugs i.e. the height of the lugs 61, 61A varies. The lugs 61, 61A are configured to be in one to one correspondence with the dimples 91 provided on the key 90. The lock assembly 1000, 2000 is configured to be operated only if the appropriate key 90 is inserted into a key slot 51,51A. In other words, if the dimple configuration 91 on the key 90 matches the lug configuration 61, 61A on the wafer plates 60, 60A only then the lock assembly 1000, 2000 is operable. The lock assembly 1000, 2000 is configured to be mounted on the operative surface of drawer or cabinet door by means of threaded wood screws passing through the door panel. The Figure 3A illustrates a front view of lock assembly in accordance with the present disclosure; the Figure 3B illustrates a top view of lock assembly in accordance with the present disclosure; the Figure 3C illustrates a bottom view of lock assembly in accordance with the present disclosure; the Figure 4A illustrates an exploded view of flat wafer plate lock assembly in accordance with the present disclosure; and the Figure 4B illustrates an exploded view of bent wafer plate lock assembly in accordance with the present disclosure. In the embodiment of the Figure 4A, the lug 61 on the wafer plate 60 lies coplanar with an operative transverse plane X of the wafer plate 60. An operative longitudinal direction L is defined in the direction in which the key 90 is inserted in the lock assembly 1000,2000. The details of the construction of the flat type wafer plate 60 is shown in the Figures 16A-16C. In the embodiment of the Figure 4B, the lug 61A on the wafer plate 60A lie offset with the operative transverse plane X of the wafer plate 60. The details of the construction of the bent type wafer plate 60A is shown in the Figures 17A-17C. In an embodiment, the construction of profile of the wafer plate 60A is a bent wafer plate (60A) having a bent type lug (61A). Figure 4B, Figures 6A-6D, Figures 15A-15C, Figure 17A-17C and Figure 20B depict a second embodiment of the present disclosure. In the second embodiment, the lock assembly 2000 includes the wafer plates 60A having the lugs 61A which are configured with a bent type construction. In the embodiment of the Figures 17A-17C, the lug 61A on the wafer plate 60A lie offset to the operative transverse plane X of the wafer plate 60 and extends in the operative longitudinal direction L. This facilitates increased smoothness of operation of the lock assembly 2000, while the key 90 having dimples 91 is rotated by a user. The key 90 has a unique configuration of dimples 91 so as to exclusively allow operation of the lock assembly 1000, 2000 by the person in possession thereof. As a result of the bent profile configured on the lugs 61A, the effort needed to perform the locking operation of the lock assembly 2000 is reduced significantly. The housing 40 is configured on the case 10 via the cover plate 20. The cover plate 20 is attached to the housing 40 with the help of lugs 41. The housing 40 is configured on the cover plate 20 by a plurality of locators 41. The lever 57, 57A are available at an operative rear end of the cylinder 50, 50A. The bolt 30 is configured to displace the lever 57, 57A within the lock case 10. The lever 57, 57A is configured on the cylinder 50, 50A. The lever 57, 57A is secured in a groove 31 of the bolt 30. A locking means is provided such as the bolt 30. The bolt 30 is further configured to be received within an aperture provided on the frame of the drawer or the frame of the cabinet door in an operative locked configuration of the lock assembly 1000, 2000. An opening 63, 63A is configured on each of the plurality of wafer plates 60, 60A. The openings 63, 63A configured in an operative central portion of the wafer plates 60, 60A for allowing passage of the key 90 having dimples 91. The opening 51, 51A is provided on the cylinder 50, 50A to receive the key 90 having dimples 91 therein. The opening 51, 51A facilitates actuation of the cylinder 50, 50A between the operative locked configuration and the operative unlocked configuration. The openings 51, 51A are in the form of keyways configured in the cylinder 50, 50A. Further, the actuation of cylinder 50, 50A is configured to linearly displace the bolt 30 from the operative unlocked configuration to the operative locked configuration or vice-versa, so as to facilitate the locking or unlocking of the drawer or cabinet door with the door frame. The cover plate 20 is mounted on the case 10. The cover plate 20 supports the actuation mechanism whereas the case 10 covers the mechanism thus obtained. The actuation mechanism of the present disclosure includes the bolt 30 and the lever 57, 57A. The lever 57, 57A is operable by the cylinder 50, 50A. The bolt 30 is slidably mounted on a cover plate 20. The actuation of cylinder 50, 50A facilitates the angular displacement of the cylinder 50, 50A in to initiate locking and unlocking of the lock assembly 1000, 2000. Further, the cover plate 20 is configured with a plurality of apertures. An aperture 22 is configured on the cover plate 20 for locating the housing 40. The apertures 26 are provided on the cover plate 20 for lock fixing screws and a snap fit element 25 for fitment of cover plate 20 with the case 10. An aperture 21 is provided on the cover plate 20 for sliding motion of the bolt 30. The aperture 22 is provided on cover plate 20 to hold the housing 40 with cover plate 20. The aperture 23 is provided on cover plate 20 to restrict the rotational movement of the housing 40 and firm fitment of the housing 40 with the cover plate 20. The cover plate 20 includes a plurality of projections 24 configured thereon for locating the bolt 30 there between. This helps in guiding the bolt 30 in a linear manner. Further, the case 10 is configured with a plurality of apertures. The aperture 11 is used for locking means. The apertures 14 facilitate fitment of lock fixing screws and the aperture 13 facilitates fitment of the case 10 with the cover plate 20. The aperture 11 is provided on side flange of the case 10 for movement of locking means i.e. the bolt 30. The case 10 includes a plurality of projections 12 configured thereon for locating the bolt 30 there in between. Locating the bolt 30 in between the projections 12 helps in realizing the sliding movement of the bolt 30. The aperture 13 is provided on the case 10 for fitment of the case 10 with the cover plate 20. An operative portion of the lever 57, 57A is configured to be pivotally engaged with a driving groove 31 configured on the bolt 30. The lever 57, 57A linearly displaces the bolt 30 by transferring angular displacement of the key 90 to the bolt 30 via the housing 40. The housing 40 includes the plurality of locators 41 configured thereon to restrict the rotational movement of the housing 40 with respect to the cover plate 20 after fitment. A plurality of steps is configured on the housing 40. A first step 42 of the plurality of steps is provided on the housing 40 for resting the cylinder 50, 50A in housing 40. A second step 43 of the plurality of steps is provided on the housing 40 to provide relief to a stopper 58, 58A configured on the cylinder 50. The second step 43 is designed as per requirement of the angular motion of the key 90 having dimples to lock or unlock the lock assembly 1000, 2000. A third step 44 of the plurality of steps is provided on the housing 40 for resting a clip plate 70. Resting of the wafer clip plate 70 on the third step 44 helps in locking the axial movement of the cylinder 50, 50A in the housing 40. A fourth step 45 of the plurality of steps is provided for resting of the wafer plates 60, 60A in the housing 40. A plurality of slots 52, 53, 54, 55, 56 is configured on the cylinder 50. Each of the wafer plates 60 is configured to be positioned in a corresponding slot 52. The slots 52 facilitate guiding the flat wafer plate 60 in lock cylinder 50. The slot 53, 53A is provided on the cylinder 50, 50A for guiding the clip plate 70 in the cylinder 50, 50A. The slot 54 is provided on the cylinder 50 for guiding an indexing ball 80 with a compression spring 81 in the cylinder 50. The slot 55, 55A is provided on the cylinder 50, 50A for guiding a compression spring 64 in the cylinder 50, 50A. The slot 56, 56A is provided on the cylinder 50, 50A for guiding the compression spring 64 in the cylinder 50, 50A. The lever 57 is provided on an operative end of lock cylinder 50 for locking and unlocking movement of bolt 30. The stopper 58 is provided on the cylinder 50 for stopping the excess rotational movement of the cylinder 50 in the housing 40. A plurality of slots 52A is provided on the cylinder 50A for guiding the bent type wafer plate 60A in lock cylinder 50A. The slot 53A is provided on the cylinder 50A for guiding the wafer clip plate 70 in the cylinder 50A. The aperture 55A is provided on lock cylinder 50A for guiding the compression spring 64 in lock cylinder 50A. The aperture 56A is provided on lock cylinder 50A for guiding the compression spring 64 in lock cylinder 50A. The lever 57A is provided on an operative end of lock cylinder 50A for locking and unlocking movement of bolt 30. The stopper 58A is provided on the cylinder 50A for stopping the excess rotational movement of the cylinder 50A in the housing 40. The lugs 61, 61A are defined on each of the wafer plates 60, 60A for engaging of the lugs 61, 61A in the array of dimples 91 on the key 90 during the insertion of the dimple key 90 in the key slot 51, 51A. A projection 62, 62A is provided on the flat wafer plate 60, bent wafer plate 60A for securing the compression spring 64. The compression spring 64 maintains the required preload in the lock assembly 1000, 2000. The openings 63, 63A are provided on the wafer plates 60, 60A for allowing passage of the key 90. When the key 90 is inserted axially through the openings 63, 63A, the key 90 comes in contact with the lugs 61, 61A defined on the wafer plates 60, 60A. Due to a chamfer provided on the dimple key edge, wafer plates 60, 60A lift off due to the lugs 61, 61A come in contact with the dimple key edge chamfer configured on the key 90. Due to continuous forward movement of the key 90 in an unobstructed manner, the lugs 61, 61A come into contact with the array of dimples 91 on the dimple key 90. Further, the lock assembly 1000 comprises a wafer clip plate 70. The projection 71 is provided on wafer clip plate 70 for holding of the compression spring 64 in projection 71. The aperture 72 is provided on wafer clip plate 70 for dimple key guiding in wafer clip plate 70. The wafer clip plate 70 restricts the axial movement of lock cylinder 50 and lock cylinder 50A and prevent it from coming out of housing 40. Further, the lock assembly 1000 comprises a dimple key 90. The dimple key 90 is provided with an array of dimples 91 profiled on both the faces of key 90. An aperture 92 is provided on the dimple key 90 for attaching a key ring. The dimple key 90 is adapted to slidingly enter a key slot 51, 51A configured on the lock cylinder 50, 50A. The array of dimples 91 are adapted to engage the lug 61, 61A in a unique sequence for aligning the slots 52, 52A, and thereby operatively move the cylinder 50, 50A with reference to the housing 40. When the lugs 61 comes into contact with the array of dimples 91 on the dimple key 90, the lock cylinder 50 rotates smoothly in clockwise and anti-clockwise direction thus locking and unlocking of the lock assembly 1000. This is depicted in the figure 20A. It can be clearly observed from the figure 20A that the contact between the lugs 61, and the dimple 91 happens at a single point, contrary to the area contact of the conventional lock assembly 1000’. Thus, friction is eliminated and ease of operation of the lock assembly 1000 is realized. When the lugs 61A comes into contact with the array of dimples 91 on the dimple key 90, the lock cylinder 50A rotates smoothly in clockwise and anti-clockwise direction thus locking and unlocking of the lock assembly 2000. This is depicted in the figure 20B. It can be clearly observed from the figure 20B that the contact between the lugs 61A and the dimples 91 happens at a single point, contrary to the area contact of the conventional lock assembly 1000’. Thus, friction is eliminated and ease of operation of the lock assembly 2000 is realized. The key 90 having dimples 91 is manufactured by the computerised numerical control (CNC) machining process. The number of key combinations is more in dimple key 90. The probability of duplicating the key 90 having dimples 91 is very less, as only the manufacturer can make this type of key 90. The key insertion and withdrawal operations in dimple key 90 is very smooth. So, chances of the wafer plate 60, 60A bending during insertion and withdrawal is very less. In an embodiment, at least one of the wafer plates 60, 60A is configured with a lug 61, 61A. In another embodiment, at least one of the wafer plates 60, 60A is configured with a plurality of lugs 61, 61A. 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 ADVANCEMENT The present disclosure described herein above has several technical advantages including, but not limited to, a lock assembly for a drawer and cabinet door, which: ^ provides improved security; ^ provides smooth locking and unlocking function; ^ is easy to be manufactured and assembled at low cost; ^ has reduced weight and dimensions; ^ facilitates large number of key combinations; and ^ is difficult to tamper and break open. The disclosure has been described with reference to the accompanying embodiments which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration. The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein. The foregoing description of the specific embodiments so fully revealed 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. Any discussion of articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application. 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 5 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. 10

Claims

CLAIMS: 1. A lock assembly (1000) for drawer and cabinet door, said lock assembly (1000) having a case (10) configured to be mounted on a surface of the drawer or the cabinet, a housing (40) configured on the cover plate (20), and a lock cylinder (50) configured to be rotatably driven within the housing (40), the lock cylinder (50) coupled to a bolt (30) of said lock assembly (1000), said lock assembly (1000) comprising: o a plurality of wafer plates (60) configured to be positioned inside slots provided on said lock cylinder (50), each of said plurality of wafer plates (60) having an opening (63) configured thereon for allowing passage of a key (90) having a unique configuration of dimples (91); and o a unique configuration of a plurality of lugs (61) defined on said plurality of wafer plates (60), said lugs (61) configured to be in one to one correspondence with the dimples (91) on the key (90), and in an operative configuration when the proper key is inserted into a key slot (51) and the key (90) is angularly displaced, the dimple configuration on the key (90) matches the lug configuration on said wafer plates (60) to thereby transfer the angular motion of the key (90) to the bolt (30) for locking and unlocking of the door.

2. The lock assembly (1000, 2000) as claimed in claim 1, wherein the bolt (30) is linearly displaced due to the angular displacement of the key (90) having dimples (91), to attain an operative locked configuration and an operative unlocked configuration of the lock assembly (1000).

3. The lock assembly (1000, 2000) as claimed in claim 1, wherein said lock cylinder (50,50A) is configured with a lever (57, 57A), said lever (57, 57A) secured in a groove (31) of the bolt (30) to displace the bolt (30) and attain the operative locked configuration and the operative unlocked configuration of the lock assembly (1000).

4. The lock assembly (1000, 2000) as claimed in claim 1, wherein said lock cylinder (50,50A) is oriented coaxial with the housing (40).

5. The lock assembly (1000, 2000) as claimed in claim 1 includes a cover plate (20) configured within the case (10), said cover plate (20) configured to secure the housing (40).

6. The lock assembly (1000, 2000) as claimed in claim 1, wherein each of said lugs (61) has a distinct height corresponding to the depth of each of the dimples on the key (90).

7. The lock assembly (1000, 2000) as claimed in claim 1, wherein said wafer plates (60, 60A) has a plurality of lugs (61, 61A), said lugs (61, 61A) configured to mate an array of dimples (91) configured on the key (90).

8. The lock assembly (1000, 2000) as claimed in claim 1, wherein said lugs (61A) lie offset to said wafer plates (60A) in an operative longitudinal direction (L).

9. The lock assembly (1000, 2000) as claimed in claim 1, wherein said opening (63, 63A) configured in an operative central portion of said wafer plates (60, 60A) for allowing passage of a key (90) having dimples (91).

10. The lock assembly (1000, 2000) as claimed in claim 1, wherein at least one of said wafer plates (60, 60A) is configured with said lug (61, 61A).

11. The lock assembly (1000, 2000) as claimed in claim 1, wherein at least one of said wafer plates (60, 60A) is configured with a plurality of said lugs (61, 61A).

12. The lock assembly (2000) as claimed in claim 1, wherein the construction profile of said wafer plate (60A) is a bent wafer plate (60A) having a bent type lug (61A).