DESC:CROSS REFERENCE TO RELATED APPLICATION
This application is based on and derives the benefit of Indian Provisional Application 202121029475 filed on 30/06/2021, the contents of which are incorporated herein by reference

TECHNICAL FIELD
[001] The embodiments herein generally relate to door lock systems, and more particularly, to a door lock apparatus with double stage hybrid locking achieved by dual directional motion of deadbolts to provide maximum security to the door.

BACKGROUND
[002] Locking devices are mechanical system which is designed to provide safety and security. Generally, rim locks are mounted along the rim of the door from inside (as shown in fig. 1). The lock body consists of mechanical system which has bolt/deadbolt. Bolts are the component which is responsible for secure locking of the door. When we operate the lock by key from outside or by knob or key from inside bolt are getting engaged in the receptacle thereby locking the door.
[003] 'Receptacle' is a component which is mounted on the door frame from inside. The receptacle has opening/slots for the bolts to engage. Latch bolt is a spring-loaded bolt has angled profile. Due to which when door is pushed to close the angled profile of bolt touches and slide over the receptacle surface and retract until the slot. Once the door fully closed, the latch bolt is engaged in the slot. Spring loaded latch bolt is commonly used for automatically locking the door for the convenience of user without operating the lock.
[004] In the conventional rim locks, the bolts are locked in one direction with latch bolt, the latch bolt consists of clip and rod. In which latch bolt is pulled inside the lock body and hold on by the clip. By which the latch bolt is retracted / disengaged and will not automatically lock even if the door is closed, until the clip is released. There is a chance of the clip releasing due to impact or door banging because the clip is just held on to the lock body surface. If this happen the latch bolt releases and door is getting locked which can be open from inside by pulling the latch or from outside by using the genuine key. Just in case if user is not carrying keys and locked outside then will not be able to open the door.

OBJECTS
[005] The principal object of embodiments herein is to provide to a door lock apparatus with double stage hybrid locking achieved by dual motion of deadbolts to provide maximum security to the door.
[006] Another object of embodiments herein is to pull and rotate latch mechanism is introduced for engagement and disengagement of latch bolt which is user friendly and provide surety of positive holding of latch bolt in retracted condition.
[007] Another object of embodiments herein is to maximize the security and appearance of the lock with new two directional locking mechanism which provides maximum security and having soft design to enhance the home interior.
[008] Another object of embodiments herein is to provide maximum security is achieved by the dual motion of deadbolts, when we operate the lock by rotating the knob or key from inside or by using the genuine key rotation from outside, the locking takes place in two stages. During the first stage the deadbolts are projected forward and engage with the receptacle. In second stage the bolts are projected vertically outward and get anchored in the receptacle, thereby making the lock anti crowbar.
[009] These and other objects of embodiments herein will be better appreciated and understood when considered in conjunction with following description and accompanying drawings. It should be understood, however, that the following descriptions, while indicating embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF DRAWINGS
[0010] The embodiments are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0011] Fig. 1 depicts a perspective view of a conventional lock;
[0012] Fig. 2 depicts an exploded view of a base plate and lock body of a door lock apparatus, according to embodiments as disclosed herein;
[0013] Fig. 3 depicts a perspective view of the base plate, according to embodiments as disclosed herein;
[0014] Fig. 4 depicts an exploded view of the base plate and deadbolt assemblies, according to embodiments as disclosed herein;
[0015] Fig. 5 depicts an exploded view of the base plate, a deadbolt moving member and a deadbolt locker, according to embodiments as disclosed herein;
[0016] Fig. 6a depicts a perspective view of a back plate, a key spindle, a key spindle follower and a key follower pin in assembled condition, according to embodiments as disclosed herein;
[0017] Fig. 6b depicts a front view of the back plate and the key spindle, according to embodiments as disclosed herein;
[0018] Fig. 7 depicts an exploded view of the privacy lock apparatus and interior lock knob, the base plate and the lock body, according to embodiments as disclosed herein;
[0019] Fig. 8 depicts another exploded view of the privacy lock apparatus and interior lock knob, the base plate and the lock body, according to embodiments as disclosed herein;
[0020] Fig. 9 depicts an exploded view of a latch bolt retention apparatus and a latch bolt assembly, according to embodiments as disclosed herein;
[0021] Fig. 10 depicts the door lock apparatus in unlocked position, according to embodiments as disclosed herein;
[0022] Fig. 11 depicts the door lock apparatus in which deadbolts is moved out in a horizontal direction to a single stage locked position, according to embodiments as disclosed herein;
[0023] Fig. 12 depicts the door lock apparatus in which deadbolts is subsequently moved out in a vertical direction to a double stage locked position, according to embodiments as disclosed herein.

DETAILED DESCRIPTION
[0024] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed 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.
[0025] The embodiments herein achieve a door lock apparatus with double stage hybrid locking achieved by dual motion of deadbolts to provide maximum security to the door. Referring now to the drawings Figs. 2 through 12, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.
[0026] Fig. 2 depicts an exploded view of a base plate and lock body of a door lock apparatus, according to embodiments as disclosed herein. Fig. 3 depicts a perspective view of the base plate, according to embodiments as disclosed herein. In an embodiment, the door lock apparatus (100) includes a lock body (101), a base plate ((102), a pair of first locating pins (103), a pair of non-linear deadbolt assemblies (104A, 104B), a pair of first guide pins (105), a deadbolt moving plate (106), a second locating pin (108), a deadbolt locker assembly (110), a deadbolt locker spring (112), a back plate (114), a key spindle (116), a key spindle follower (118), a key follower pin (120), an interior lock knob (122), a lock knob cam (124), a lock knob follower (126), a pair of knob follower pins (128), a lock knob spring (130), a washer (131W), a screw (131S), a privacy lock apparatus (200), a latch bolt retention apparatus (500) and a latch bolt assembly (600). For the purpose of this description and ease of understanding, the door lock apparatus (100) is explained herein with below reference to be provided in a door installed in room. However, it is also within the scope of the invention to use/practice door lock apparatus (100) in doors of vaults or safes or any other storage systems without otherwise deterring the intended function of the door lock apparatus (100) as can be deduced from the description and corresponding drawings.
[0027] Fig. 3 depicts a perspective view of the base plate (102), according to embodiments as disclosed herein. The base plate (102) mounted into the lock body (101). The base plate (102) defines a pair of first non-linear deadbolt guide ways (102A) and a pair of second non-linear deadbolt guide ways (102B). The base plate (102) defines an elongated slot (102S) adapted to receive the first locating pins (103) therethrough. Each first and second non-linear deadbolt guide way (102A, 102B) defined on the base plate (102) includes a horizontal guide way (102AH, 102BH) and a vertical guide way (102AV, 102BV) adjoining the horizontal guide way (102AH, 102BH). Each first and second non-linear deadbolt guide way (102A, 102B) defined on the base plate (102) substantially defines a L shape. Each first non-linear deadbolt guide way (102A) is parallel and spaced away from another first non-linear deadbolt guide way (102A). Each second non-linear deadbolt guide way (102B) is parallel and spaced away from another second non-linear deadbolt guide way (102B). A fore (leading) end of each first non-linear deadbolt guide way (102A) is positioned offset with respect to a fore end of another first non-linear deadbolt guide way (102A). A fore (leading) end of each second non-linear deadbolt guide way (102B) is positioned offset with respect to a fore end of another second non-linear deadbolt guide way (102B).
[0028] Each non-linear deadbolt assembly (104A, 104B) is movably connected to the base plate (102). Each deadbolt assembly (104A, 104B) includes a non-linear deadbolt (104AB, 104BB), a deadbolt plate (104AP, 104BP) and a pair of deadbolt guide pins ((104AG, 104BG), only one of which is shown in fig. 4)). The deadbolt plate (104AP, 104BP) is connected to the non-linear deadbolt (104AB, 104BB). Each non-linear deadbolt (104AB, 104BB) includes a horizontal portion (104AH, 104BH) and a vertical portion (104AV, 104BV) adjoining the horizontal portion (104AH, 104BH). Each non-linear deadbolt (104AB, E104BB) substantially defines a L shape. The deadbolt plate (104AP, 104BP) defines an elongated angular slot (104APS, 104BPS). The deadbolt guide pins (104AG, 104BG) are defined on the deadbolt plate (104AP). Each deadbolt guide pin (104AG, 104BG) is movably engaged with corresponding non-linear deadbolt guide ways (102A, 102B). The first locating pins (103) defined on the base plate (102), wherein each first locating pin (103) is parallel and spaced away from another the first locating pin (103).
[0029] The deadbolt moving member (106) movably supported onto the base plate (102), wherein the deadbolt moving member (106) is movably connected to the non-linear deadbolt assemblies (104A, 104B). The first guide pins (105) located on the deadbolt moving member (106), wherein each first guide pin (105) is movably engaged with corresponding elongated angular slot (104APS, 104BPS) of the deadbolt plate (104AP, 104BP). The second locating pin (108) defined on the base plate (102). The deadbolt locker assembly (110) adapted to be movably connected to the base plate (102) through the second locating pin (108) and corresponding first locating pin (103). The deadbolt locker (110) includes a pair of deadbolt locker plates (110P), where at least one of the deadbolt locker plates (110P) defines a locking flange (110L). The deadbolt locker spring (112) located on another first locating pin (103). The deadbolt moving plate (106) is located in between deadbolt locker plates (110P) of the deadbolt locker assembly (110). Each deadbolt locker plates (110P) define a pair of first elongated slots (110PA) and a second elongated slot (110PB). Each first elongated slot (110PA) defined in each deadbolt locker plate (110P) is adapted to receive corresponding first locating pin (103) therethrough, and correspondingly the second elongated slot (110PB) is adapted to receive the second locating pin (108) therethrough, thereby movably positioning the deadbolt locker assembly (110) on the base plate (102). Both ends of the deadbolt locker spring (112) is connected to spring retainers ((110PS), only one of which is shown in fig. 5)) defined on corresponding deadbolt locker plate (110P).
[0030] The back plate (114) is supported on the lock body (101). The back plate (114) is positioned opposite to the base plate (102). The key spindle (116) adapted to be rotatably connected to back plate (114). The key spindle follower (118) connected to the key spindle (116). The key follower pin (120) defined on the key spindle follower (118). The key follower pin (120) is adapted to move the deadbolt locker assembly (110) to an unlocked position in which the locking flange (110L) is disengaged from a corresponding locking groove (106LA) defined on deadbolt moving member (106) on rotation of the key spindle (116) by using genuine key, and the key follower pin (120) is adapted to move the non-linear deadbolts (104AB, 104BB) through the deadbolt moving plate (106) in a horizontal direction and a vertical direction to facilitate double stage locking on further rotation of the key spindle (116) by using genuine key.
[0031] The interior lock knob (122) adapted to be rotatably connected to the lock body (101) through a spacer (125). The lock knob cam (124) adapted to be connected to the interior lock knob (122). The lock knob follower (126) is adapted to be connected to the interior lock knob (122) adjacent to the lock knob cam (124). The knob follower pins (128) are located on the lock knob follower (126). The lock knob spring (130) is located on a stud defined on the lock body (101) and retained thereon through a washer (131W) and screw (131S), wherein one end of the lock knob spring (130) is connected to the interior lock knob (122) and another end of the lock knob spring (130) is connected to the base plate (102). The lock knob spring (130) is adapted to move the interior lock knob (122) to its initial position upon releasing the interior lock knob (122). The knob follower pin (128) is adapted to move the deadbolt locker (110) to an unlocked position in which the locking flange (110L) is disengaged from a corresponding another locking groove (106LB) defined on deadbolt moving member (106) on rotation of the interior lock knob (122), and corresponding the knob follower pin (128) is adapted to move the non-linear deadbolts (104AB, 104BB) through the deadbolt moving plate (106) in a horizontal direction and a vertical direction to facilitate double stage locking on further rotation of the interior lock knob (122). The non-linear deadbolts (104AB, 104BB) are received into receptacle in the locked position. The deadbolt locker spring (112) is adapted to move the deadbolt locker assembly (110) to a first locked position in which the locking flange (110L) of the deadbolt locker assembly (110) is engaged with a first locking groove (106LB) defined on the deadbolt moving member (106) when said non-linear deadbolts (104AB, 104BB) is in a single stage locking position. The deadbolt locker spring (112) is adapted to move the deadbolt locker assembly (110) to a second locked position in which the locking flange (110L) of said deadbolt locker assembly (110) is engaged with a second locking groove (106LC) defined on the deadbolt moving member (106) when the non-linear deadbolts (104AB, 104BB) is in the double stage locking position.
[0032] The latch bolt actuating arm (132) adapted to be rotatably connected to the deadbolt moving plate (106) through a bush (133). The latch bolt follower (134) connected to the latch bolt actuating arm (132). The latch bolt follower spring (136), where one end of the latch bolt follower spring (136) is connected to the latch bolt follower (134) and another end of the latch bolt follower spring (136) is connected to the deadbolt moving plate (106). The locking member (138) adapted to secure the latch bolt actuating arm (132) and the latch bolt follower (134) onto the deadbolt moving member (106) by using a bush (133). The latch bolt actuating arm (132) is adapted to move the latch bolt (602) to unlocked position upon operating by one of genuine key and the interior lock knob (122).
[0033] The privacy lock apparatus (200) includes a privacy lock knob (202), a privacy lock member (206), a privacy lock knob follower (204), a privacy lock guide pin (207), a privacy lock spring (208), a privacy lock indicator, a plurality of fasteners (210) and a plurality of washers (212). The privacy lock knob (202) adapted to be movably connected to a lock body (101) of the door lock apparatus (100) through a privacy lock knob washer (203). The privacy lock member (206) adapted to be slidably connected to the lock body (101). The privacy lock knob follower (204) adapted to be connected to privacy lock knob (202) and the privacy lock member (206). The privacy lock spring (208), wherein one end of the privacy lock spring (208) is connected with the privacy lock knob follower (204) and another end of the privacy lock spring (208) is connected to a base plate (102) of the door lock apparatus (100). The privacy lock knob (202) is adapted to move the privacy lock member (204) to one of a locked position and an unlocked position. In the locked position, the privacy lock member (204) is engaged with a deadbolt moving member (106) thereby maintaining a pair of deadbolts (104A, 104B) in a locked position only when the deadbolts (104A, 104B) are pre-moved to the locked position. In the unlocked position, privacy lock member (204) is disengaged from the deadbolt moving member (106). The privacy lock guide pin (207) defined on the privacy lock knob follower (204). The privacy lock indicator adapted to be connected to the privacy lock knob (202), wherein the privacy lock indicator is adapted to indicate one of the locked position and the unlocked position of the privacy lock member (204). The color indication provided below the interior lock knob 202 shows ‘enabled’ and ‘disabled’ condition of privacy. Red indicates privacy is disabled and green indicates privacy is enabled. The privacy lock member (206) defines an elongated angular slot (206C), a locking flange (206F) and a plurality of elongated locating slots (206L). The privacy lock guide pin (207) is engaged with the elongated angular slot (206C) of the privacy lock member (206). The locking flange (206F) of the privacy lock member (206) is one of engaged and disengaged with respect to the deadbolt moving member (106) when the privacy lock member (206) is in one of the locked position and unlocked position respectively. Each elongated locating slot (206L) of the privacy lock member (206) is adapted to receive corresponding fastener (210) which is connected to corresponding locating studs defined on the lock body (101). Each washer (212) is fitted onto corresponding the fastener (210) to support the privacy lock member (206) onto the lock body (101). The privacy lock member (206) in the locked position is adapted to restrict movement of the deadbolts ((104AB, 104BB) from the locked position to the unlocked position upon operating the deadbolts (104AB, 104BB) by using genuine key or the interior lock knob (122) unless the privacy member (206) is moved to the unlocked position.
[0034] The latch bolt retention apparatus (500) includes a latch bolt retention handle (502), a latch bolt retention rod (504), a locking member (505), a rod guide member (506) and a latch bolt retention spring (508). The latch bolt retention rod (504), where one end of the latch bolt retention rod (504) is connected to the latch bolt retention handle (502) and another end of the latch bolt retention rod (504) is supported on a latch bolt guide bracket (604) which is slidably connected to a base plate (102) of door lock apparatus (100). The locking member (505) located on the latch bolt retention rod (504). The rod guide member (506) is mounted onto the base plate (102). The rod guide member (506) is adapted to receive the latch bolt retention rod (504) therethrough. The latch bolt retention spring (508) inserted over with the latch bolt retention rod (504) and is engaged with the latch bolt guide bracket (604). The latch bolt retention handle (502) is adapted to be pulled to move a latch bolt (602) to a retracted position, and the locking member (505) is adapted to engage the rod guide member (506) to maintain the latch bolt (602) in the retracted position when the latch handle (502) is rotated in a first direction. The latch bolt retention handle (502) is adapted to be rotated in a second direction to disengage the locking member (505) from the rod guide member (506) thereby moving the latch bolt (602) to an extended position, where the second direction is opposite to the first direction. The latch bolt spring retainer (606) mounted onto a shaft (602S) of latch bolt (602). The latch bolt spring (608) inserted over the shaft (602S) of the latch bolt (602), wherein one end of the latch bolt spring (608) is engaged with the latch spring retainer (606) and another end of the latch bolt spring (608) is engaged with the latch bolt guide bracket (604). The shaft (602S) of the latch bolt (602) is supported into the latch bolt guide bracket (604).
[0035] The technical advantages of the door lock apparatus (100) are as follows. The lock apparatus with double stage hybrid locking is achieved by dual motion of deadbolts to provide maximum security to the door. To pull and rotate latch mechanism is introduced for engagement and disengagement of latch bolt which is user friendly and provide surety of positive holding of latch bolt in retracted condition. To maximize the security and appearance of the lock with new two directional locking mechanism which provides maximum security and having soft design to enhance the home interior.
[0036] The foregoing description of the specific embodiments will so fully reveal 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 embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modifications within the spirit and scope of the embodiments as described herein.
,CLAIMS:1. A door lock apparatus (100) comprising:
a base plate (102) mounted into a lock body (101), said base plate (102) defines a pair of first non-linear deadbolt guide ways (102A) and a pair of second non-linear deadbolt guide ways (102B);
a pair of non-linear deadbolt assemblies (104A, 104B), each of said non-linear deadbolt assembly (104A, 104B) is movably connected to said base plate (102); and
a deadbolt moving member (106) movably supported onto said base plate (102), wherein said deadbolt moving member (106) is movably connected to said non-linear deadbolt assemblies (104A, 104B).

2. The door lock apparatus (100) as claimed in claim 1, wherein each of said deadbolt assembly (104A, 104B) includes,
a non-linear deadbolt (104AB, 104BB);
a deadbolt plate (104AP, 104BP) connected to said non-linear deadbolt (104AB, 104BB), wherein said deadbolt plate (104AP, 104BP) defines an elongated angular slot (104APS, 104BPS); and
a pair of deadbolt guide pins (104AG, 104BG) defined on said deadbolt plate (104AP), wherein each of said deadbolt guide pin (104AG, 104BG) is movably engaged with corresponding said non-linear deadbolt guide ways (102A, 102B).

3. The door lock apparatus (100) as claimed in claim 2, wherein said door lock apparatus (100) includes,
a pair of first guide pins (105) located on said deadbolt moving member (106), wherein each of said first guide pin (105) is movably engaged with corresponding elongated angular slot (104APS, 104BPS) of said deadbolt plate (104AP, 104BP); and
a pair of first locating pins (103) defined on said base plate (102), wherein each of said first locating pin (103) is parallel and spaced away from another said first locating pin (103),
wherein
said base plate (102) defines an elongated slot (102S) adapted to receive said first locating pins (103) therethrough;
each of said non-linear deadbolt (104AB, 104BB) includes a horizontal portion (104AH, 104BH) and a vertical portion (104AV, 104BV) adjoining said horizontal portion (104AH, 104BH); and
each of said non-linear deadbolt (104AB, 104BB) substantially defines a L shape.

4. The door lock apparatus (100) as claimed in claim 1, wherein each of said first and second non-linear deadbolt guide way (102A, 102B) defined on said base plate (102) includes a horizontal guide way (102AH, 102BH) and a vertical guide way (102AV, 102BV) adjoining said horizontal guide way (102AH, 102BH);
each of said first and second non-linear deadbolt guide way (102A, 102B) defined on said base plate (102) substantially defines a L shape;
each of said first non-linear deadbolt guide way (102A) is parallel and spaced away from another said first non-linear deadbolt guide way (102A);
each of said second non-linear deadbolt guide way (102B) is parallel and spaced away from another said second non-linear deadbolt guide way (102B);
a fore (leading) end of each of said first non-linear deadbolt guide way (102A) is positioned offset with respect to a fore end of another said first non-linear deadbolt guide way (102A); and
a fore (leading) end of each of said second non-linear deadbolt guide way (102B) is positioned offset with respect to a fore end of another said second non-linear deadbolt guide way (102B).
5. The door lock apparatus (100) as claimed in claim 1, wherein said door lock apparatus (100) includes,
a second locating pin (108) defined on said base plate (102);
a deadbolt locker assembly (110) adapted to be movably connected to said base plate (102) through said second locating pin (106) and corresponding said first locating pin (103), said deadbolt locker assembly (110) includes a pair of deadbolt locker plates (110P)), at least one of said deadbolt locker plate (110P) defines a locking flange (110L); and
a deadbolt locker spring (112) located on corresponding another said first locating pin (103), where both ends of said deadbolt locker spring (112) is connected to spring retainers (110PS) defined on corresponding said deadbolt locker plate (110P),
wherein
said deadbolt moving plate (106) is located in between said deadbolt locker plates (110P).

6. The door lock apparatus (100) as claimed in claim 1, wherein said door lock apparatus (100) includes,
a back plate (114) is supported on the lock body (101);
a key spindle (116) adapted to be rotatably connected to said back plate (114);
a key spindle follower (118) connected to said key spindle (116); and
a key follower pin (120) defined on said key spindle follower (118),
wherein
said key follower pin (120) is adapted to move said deadbolt locker assembly (110) to an unlocked position in which the locking flange (110L) is disengaged from a neutral locking groove (106LA) defined on deadbolt moving member (106) on rotation of said key spindle (116) by using genuine key, and said key follower pin (120) is adapted to move said non-linear deadbolts (104AB, 104BB) through said deadbolt moving plate (106) in a horizontal direction and a vertical direction to facilitate double stage locking on further rotation of said key spindle (116) by using genuine key.

7. The door lock apparatus (100) as claimed in claim 6, wherein lock apparatus (100) includes,
an interior lock knob (122) adapted to be rotatably connected to said lock body (101) through a spacer (125);
a lock knob cam (124) adapted to be connected to said interior lock knob (122);
a lock knob follower (126) adapted to be connected to said interior lock knob (122) adjacent to said lock knob cam (124); and
a pair of knob follower pins (128) located on said lock knob follower (126); and
a lock knob spring (130) located on a stud defined on said lock body (101) and retained thereon through a washer (131W) and screw (131S), wherein one end of said lock knob spring (130) is connected to said interior lock knob (110) and another end of said lock knob spring (130) is connected to said base plate (102),
wherein
corresponding said knob follower pin (128) is adapted to move said deadbolt locker (110) to an unlocked position in which the locking flange (110L) is disengaged from a corresponding another locking groove (106LB) defined on deadbolt moving member (106) on rotation of said interior lock knob (122), and corresponding said knob follower pin (128) is adapted to move said non-linear deadbolts (104AB, 104BB) through said deadbolt moving plate (106) in a horizontal direction and a vertical direction to facilitate double stage locking on further rotation of said interior lock knob (122);
said deadbolt locker spring (112) is adapted to move said deadbolt locker assembly (110) to a first locked position in which said locking flange (110L) of said deadbolt locker assembly (110) is engaged with a first locking groove (106LB) defined on said deadbolt moving member (106) when said non-linear deadbolts (104AB, 104BB) is in a single stage locking position;
said deadbolt locker spring (112) is adapted to move said deadbolt locker assembly (110) to a second locked position in which said locking flange (110L) of said deadbolt locker assembly (110) is engaged with a second locking groove (106LC) defined on said deadbolt moving member (106) when said non-linear deadbolts (104AB, 104BB) is in the double stage locking position; and
said lock knob spring (130) is adapted to move said interior lock knob (122) to its initial position upon releasing said interior lock knob (122).

8. A privacy lock apparatus (200) in a door lock apparatus (100), said privacy lock apparatus (200) comprising:
a privacy lock knob (202) adapted to be movably connected to a lock body (101) of the door lock apparatus (100);
a privacy lock member (206) adapted to be slidably connected to the lock body (101);
a privacy lock knob follower (204) adapted to be connected to said privacy lock knob (202) and said privacy lock member (206); and
a privacy lock spring (208), wherein one end of said privacy lock spring (208) is connected with said privacy lock knob follower (204) and another end of said privacy lock spring (208) is connected to a base plate (102) of the door lock apparatus (100).

9. The privacy lock apparatus (200) as claimed in claim 8 and claim 1, wherein said privacy lock knob (202) is adapted to move said privacy lock member (204) to one of,
a locked position in which said privacy lock member (204) is engaged with a deadbolt moving member (106) thereby maintaining a pair of deadbolts (104AB, 104BB) in a locked position only when the deadbolts (104AB, 104BB) are pre-moved to the locked position; and
an unlocked position in which said privacy lock member (204) is disengaged from the deadbolt moving member (106).

10. The privacy lock apparatus (200) as claimed in claim 7 and claim 9, wherein said privacy lock apparatus (200) includes,
a privacy lock knob washer (203) adapted to movably connect said privacy lock knob (202) to said lock body (101);
a privacy lock guide pin (207) defined on said privacy lock knob follower (204);
a privacy lock indicator adapted to be connected to said privacy lock knob (202), wherein said privacy lock indicator is adapted to indicate one of the locked position and the unlocked position of said privacy lock member (204);
a plurality of fasteners (210);
a plurality of washers (212);
wherein
said privacy lock member (206) defines an elongated angular slot (206C), a locking flange (206F) and a plurality of elongated locating slots (206L); and
said privacy lock guide pin (207) is movably engaged with said elongated angular slot (206C) of said privacy lock member (206);
said locking flange (206F) of said privacy lock member (206) is one of engaged and disengaged with respect to the deadbolt moving member (106) when said privacy lock member (206) is in one of said locked position and unlocked position respectively;
said privacy lock member (206) in said locked position is adapted to restrict movement of the deadbolts ((104AB, 104BB) from the locked position to the unlocked position upon operating the deadbolts (104AB, 104BB) by using genuine key or the interior lock knob (122) unless said privacy member (206) is moved to the unlocked position;
each of said elongated locating slot (206L) of said privacy lock member (206) is adapted to receive corresponding fastener (210) which is connected to corresponding locating studs defined on the lock body (101); and
each of said washer (212) is fitted onto corresponding said fastener (210) to support said privacy lock member (206) onto the lock body (101).

11. A latch bolt retention apparatus (500) in a door lock apparatus (100), wherein said latch bolt retention apparatus (500) comprising:
a latch bolt retention handle (502);
a latch bolt retention rod (504), where one end of said latch bolt retention rod (504) is connected to said latch bolt retention handle (502) and another end of said latch bolt retention rod (504) is supported on a latch bolt guide bracket (604) which is slidably connected to a base plate (102) of the door lock apparatus (100);
a locking member (505) located on said latch bolt retention rod (504);
a rod guide member (506) mounted onto the base plate (102), said rod guide member (506) is adapted to receive said latch bolt retention rod (504) therethrough; and
a latch bolt retention spring (508) inserted over with said latch bolt retention rod (504) and is engaged with the latch bolt guide bracket (604).

12. The latch bolt retention apparatus (500) as claimed in claim 11 and claim 1, wherein said latch bolt retention handle (502) is adapted to be pulled to move a latch bolt (602) to a retracted (unlocked) position, and said locking member (505) is adapted to engage said rod guide member (506) to maintain the latch bolt (602) in the retracted position when said latch handle (502) is rotated in a first direction; and
said latch bolt retention handle (502) is adapted to be rotated in a second direction to disengage said locking member (505) from said rod guide member (506) thereby moving the latch bolt (602) to an extended (locked) position, where the second direction is opposite to the first direction.

13. The apparatus (100, 500) as claimed in claim 1 and claim 12, wherein said latch bolt assembly (600) includes,
a latch bolt spring retainer (606) mounted onto a shaft (602S) of said latch bolt (602); and
a latch bolt spring (608) inserted over the shaft (602S) of said latch bolt (602), wherein one end of said latch bolt spring (608) is engaged with said latch spring retainer (606) and another end of said latch bolt spring (608) is engaged with the latch bolt guide bracket (604),
wherein
the shaft (602S) of said latch bolt (602) is supported into said latch bolt guide bracket (604) .

14. The lock apparatus (100, 500) as claimed in claim 7 and claim 13, wherein said lock apparatus (100) includes,
a latch bolt actuating arm (132) adapted to be rotatably connected to the deadbolt moving plate (106);
a latch bolt follower (134) connected to said latch bolt actuating arm (132);
a latch bolt follower spring (136), where one end of said latch bolt follower spring (136) is connected to said latch bolt follower (134) and another end of said latch bolt follower spring (136) is connected to the deadbolt moving member (106); and
a locking member (138) adapted to secure said latch bolt actuating arm (132) and said latch bolt follower (134) onto the deadbolt moving member (106) by using a bush (133),
wherein
said latch bolt actuating arm (132) is adapted to move the latch bolt (602) to unlocked position upon operating by one of genuine key and said interior lock knob (122).