Title of Invention	A LOCKING SYSTEM
Abstract	ABSTRACT The present invention discloses a locking system comprising a pin tumbler lock having plurality of pin tumblers (18), the pin tumbler lock comprising a shell (9) having a first slot (19) and second slot (21), a plug (8) being accommodated within the shell (9) through the first slot (19), the plug (8) comprises a key receiving slot (15) and a plurality of bores (20) for receiving the pin tumblers; a locking bar (14) being accommodated inside the second slot (21) of the shell (9), the locking bar (14) comprises a plurality of projections (25) adapted to be engaged with notches (24) of the pin tumblers (18),a pair of springs (17) to be located in a hole provided in the locking bar (14) for controlling movement of the pin tumblers (18); an orientation block (23) for accommodating the pin tumblers (18), and a key for operating the pin tumbler lock through the key receiving slot (15) of the plug (8), the key comprising:a flat key blade (2) extending along a longitudinal insert axis,a front face having front angled edges (6 & 7), and a pair of side faces (5), the each side face having atleast one longitudinally extended groove (3) near the middle of the blade (2) in full length of the blade and having depth less than half of thickness of the blade and a plurality of angled grooves (4) having depth less than half of thickness of the blade transversely directed to the side faces extending through the edge of the blade on each side faces (5) positioned diagonally opposite edge of the blade, wherein when the key is inserted in a key receiving slot (15) and rotated, the pin tumblers (18) slide freely with respect to the plurality of angled grooves (4) of the key (1) into the bores (20) of plug (8) and the orientation slot (23) by means of the springs (17) for locking purpose. FIG. 8

Title of Invention

A LOCKING SYSTEM

Abstract

ABSTRACT The present invention discloses a locking system comprising a pin tumbler lock having plurality of pin tumblers (18), the pin tumbler lock comprising a shell (9) having a first slot (19) and second slot (21), a plug (8) being accommodated within the shell (9) through the first slot (19), the plug (8) comprises a key receiving slot (15) and a plurality of bores (20) for receiving the pin tumblers; a locking bar (14) being accommodated inside the second slot (21) of the shell (9), the locking bar (14) comprises a plurality of projections (25) adapted to be engaged with notches (24) of the pin tumblers (18),a pair of springs (17) to be located in a hole provided in the locking bar (14) for controlling movement of the pin tumblers (18); an orientation block (23) for accommodating the pin tumblers (18), and a key for operating the pin tumbler lock through the key receiving slot (15) of the plug (8), the key comprising:a flat key blade (2) extending along a longitudinal insert axis,a front face having front angled edges (6 & 7), and a pair of side faces (5), the each side face having atleast one longitudinally extended groove (3) near the middle of the blade (2) in full length of the blade and having depth less than half of thickness of the blade and a plurality of angled grooves (4) having depth less than half of thickness of the blade transversely directed to the side faces extending through the edge of the blade on each side faces (5) positioned diagonally opposite edge of the blade, wherein when the key is inserted in a key receiving slot (15) and rotated, the pin tumblers (18) slide freely with respect to the plurality of angled grooves (4) of the key (1) into the bores (20) of plug (8) and the orientation slot (23) by means of the springs (17) for locking purpose. FIG. 8

Full Text	FIELD OF THE INVENTION The present invention relates to a flat key. More particularly this invention concerns such a key which is designed to provide a particularly great number of different bittings / variations and pick resistant. Further it is intended to have a reversible operation ability. BACKGROUND OF THE INVENTION Present locks and locking systems having a flat key with key blade extending along a longitudinal insert axis, having a face formed with angled cutout and having pair of faces atleast one of which is formed with atleast one longitudinally extending groove. A lock core rotatable in a lock housing has a passage complementarity to the key blade and formed with a longitudinally extending ridge complementary engageable in the main groove. The key blade fits along the axis into the passage. Primary tumbler displaceable transversely in the core are engageable transversely with the bitting of the key blade in the passage and a secondary tumbler element in the core has a feeler end and is displaceable transversely in the core and housing between the inner position with the end engaged complementarily transversely in the bit groove of the key blade in the passage and the element permitting relative rotation of the core and housing and an outer position with the end not engaged in the bit groove and the element preventing relative rotation of the core and housing. While this system is fairly good, it still could stand some improvement. The ability to make a set of identically bitted keys that nonetheless have a master status could be improved on. In addition the key itself could be made somewhat stronger inspire of the various cutouts made in it. Further the operations can be made reversible. OBJECTS OF THE INVENTION It is therefore an object of the present invention to provide an improved flat key. Another object is provision of such an improved flat key which overcomes the above given disadvantages, that is which can be easily set up for mastering and which is physically more strong than the simple bitted key. Further, object of the invention is to provide an improved key with a reversible operation ability. Still further object of the invention is to provide an improved key which is pick resistant. STATEMENT OF INVENTION A locking system comprising; a pin tumbler lock having plurality of pin tumblers (18), the pin tumbler lock comprising: a shell (9) having a first slot (19) and second slot (21),a plug (8) being accommodated within the shell (9) through the first slot (19), the plug (8) comprises a key receiving slot (15) and a plurality of bores (20) for receiving the pin tumblers; a locking bar (14) being accommodated inside the second slot (21) of the shell (9), the locking bar (14) comprises a plurality of projections (25) adapted to be engaged with notches (24) of the pin tumblers (18), a pair of springs (17) to be located in a hole provided in the locking bar (14) for controlling movement of the pin tumblers (18); an orientation block (23) for accommodating the pin tumblers (18), and a key for operating the pin tumbler lock through the key receiving slot (15) of the plug (8), the key comprising; a flat key blade (2) extending along a longitudinal insert axis,a front face having front angled edges (6 & 7), and a pair of side faces (5), the each side face having atleast one longitudinally extended groove (3) near the middle of the blade (2) in full length of the blade and having depth less than half of thickness of the blade and a plurality of angled grooves (4) having depth less than half of thickness of the blade transversely directed to the side faces extending through the edge of the blade on each side faces (5) positioned diagonally opposite edge of the blade, wherein when the key is inserted in a key receiving slot (15) and rotated, the pin tumblers (18) slide freely with respect to the plurality of angled grooves (4) of the key (1) into the bores (20) of plug (8) and the orientation slot (23) by means of the springs (17) for locking purpose. SUMMARY OF THE INVENTION The key has according to the invention a flat key body having a blade extending along a longitudinal insert axis and having a front face formed with angled cutouts, an opposite longitudinally extending back edge and a pair of oppositely directed faces. Each face is formed with atleast one longitudinally extending front grooves adjacent the front edge a full length of the blade and having depths equal to less than half of a transverse thickness of the blade and an elongated angled groove extending transversely to the front face. The angled groove of the one face extends parallel to the angled groove of the other face, that is the axis of the angled grooves on one face are parallel to each other of the grooves on the other face. According to this invention the front groove closest to the back edge and the front edge are the same across an entire series of keys. Each face is formed in accordance with this invention with a plurality of such angled groove extending parallel to one another. More particularly, each face has pluralities of angled grooves. According to another feature of the invention, each of the angled groove ends in the edge face on the respective side and each side has a clear uninterrupted land extending along the insert axis. Accordingly there is provided a key having a flat key blade extending along a longitudinal axis and having front face formed with angled cutout and a pair of side faces; each side face having atleast one longitudinally extended grooves near the middle of the blade in full length of the blade and having depths less than half of thickness of the blade and a multiplicity of angled grooves transversely directed to side faces extending through the edge of the blade on both side faces positioned diagonally on opposite edge of the blade. BRIEF DESCRIPTION OF THE DRAWING The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which: FIG 1 : Shows the elevation of the present invention. FIG 2 : Shows the basic views of present invention. FIG 3 : Shows the enlarged view of side view of present invention. FIG 4 : Shows the enlarged view of bottom view of present invention. FIG 5 : Shows the key assembly with cylinder of present invention. FIG 6 : Shows the cross sectional view of the present invention along the line B B of present invention. FIG 7 : Shows the cross sectional view along the line A A of invention. FIG 8 : Shows the exploded view of the working lock for present invention. FIG 9 : Shows the cross sectional view of the existing lock along the line AA FIG 10 : Shows the cross sectional view of the existing locks along the line BB SPECIFIC DESCRIPTION As seen in FIG I to 4. a key (I) according to this invention has a flat blade (2) and key slot (3). The key blade (2) has a front angled edges (6) & (7) as well as oppositely directed and transversely extending side faces (5). Each side face (5) is fo"rmed with atleast one longitudinally extending groove (3) of uniform section and extending the full length of the blade (2) as well as plurality of angled grooves (4) extending transversely and opening in the edge face. FIG 5 shows the lock for the key. According to this invention, which is basically cylindrical plug (8) rotatable in shell (9). The plug (8) has formed with passage (15) of similar cross section of the key to be inserted in to the plug (8) and the shell is provided with an axial groove (19). The working of the key of present invention is as per the shown figure 5, 6, 7 and 8. This consists of a pin tumbler lock comprising a shell, a plug within said shell, said plug rotatable by key means, the plug having plurality of bore means for receiving pin tumblers, the bore means being substantially normal to the axis of plug, shell having another slot means for receiving locking bar. Therein, the slot means being aligned with plug slot, means in the plug for forcing locking bar into shell slot means, and means for forcing the pin tumbler towards orientation block thereby misaligning the tumbler notches to prevent the locking bar entering within the notches, thereby projecting the locking bar into shell slot means, thereby preventing the plug rotation with respect to shell. The pin tumblers have notches to receive the locking block projection when aligned by keywards. With reference to figure 5 to 8 which illustrates the present invention, the plug (8) comprises of slot (15) to receive key (I), blind bores (20), slot (21) normal to the bore, slot (22) along with the center line of the bores. The tumblers are forced by the spring (I I) towards the orientation block (23). This enable misalignment of tumbler notches (24) thereby preventing the locking bar projections (16) to move inside the tumbler notches (24). This avoids the plug rotation with respect to shell (9). The shell (9) comprises of slot (21) adapted to receive the locking bar (14) The key (I) comprises of projections (angled grooves) (4) of different variations. The plug is rotatably retained in shell (9) by circlip (10) The locking bar (14) comprises of projections (25) adapted to be engaged with notches (24) of pin tumbler (18) and holes to receive spring (17) which retains it against the slot (19) of shell (9) thereby allowing the pin tumbler (18) to slide with respect to projection (4) of key (I) freely into the bores (20) of plug (8). WE CLAIM: 1. A locking system comprising: a pin tumbler lock having plurality of pin tumblers (18), the pin tumbler lock comprising: - a shell (9) having a first slot (19) and second slot (21), - a plug (8) being accommodated within the shell (9) through the first slot (19), the plug (8) comprises a key receiving slot (15) and a plurality of bores (20) for receiving the pin tumblers; a locking bar (14) being accommodated inside the second slot (21) of the shell (9), the locking bar (14) comprises a plurality of projections (25) adapted to be engaged with notches (24) of the pin tumblers (18), a pair of springs (17) to be located in a hole provided in the locking bar (14) for controlling movement of the pin tumblers (18); an orientation block (23) for accommodating the pin tumblers (18), and a key for operating the pin tumbler lock through the key receiving slot (15) of the plug (8), the key comprising: a flat key blade (2) extending along a longitudinal insert axis, a front face having front angled edges (6 & 7), and a pair of side faces (5), the each side face having atleast one longitudinally extended groove (3) near the middle of the blade (2) in full length of the blade and having depth less than half of thickness of the blade and a plurality of angled grooves (4) having depth less than half of thickness of the blade transversely directed to the side faces extending through the edge of the blade on each side faces (5) positioned diagonally opposite edge of the blade, wherein when the key is inserted in a key receiving slot (15) and rotated, the pin tumblers (18) slide freely with respect to the plurality of angled grooves (4) of the key (1) into the bores (20) of plug (8) and the orientation slot (23) by means of the springs (17) for locking purpose.

Full Text

FIELD OF THE INVENTION
The present invention relates to a flat key. More particularly this invention concerns such a key which is designed to provide a particularly great number of different bittings / variations and pick resistant. Further it is intended to have a reversible operation ability.
BACKGROUND OF THE INVENTION
Present locks and locking systems having a flat key with key blade extending along a longitudinal insert axis, having a face formed with angled cutout and having pair of faces atleast one of which is formed with atleast one longitudinally extending groove. A lock core rotatable in a lock housing has a passage complementarity to the key blade and formed with a longitudinally extending ridge complementary engageable in the main groove. The key blade fits along the axis into the passage. Primary tumbler displaceable transversely in the core are engageable transversely with the bitting of the key blade in the passage and a secondary tumbler element in the core has a feeler end and is displaceable transversely in the core and housing between the inner position with the end engaged complementarily transversely in the bit groove of the key blade in the passage and the element permitting relative rotation of the core and housing and an outer position with the end not engaged in the bit groove and the element preventing relative rotation of the core and housing. While this system is fairly good, it still could stand some improvement. The ability to make a set of identically bitted keys that nonetheless have a master status could be improved on. In addition the key itself could be made somewhat stronger inspire of the various cutouts made in it. Further the operations can be made reversible.

OBJECTS OF THE INVENTION
It is therefore an object of the present invention to provide an improved flat key. Another object is provision of such an improved flat key which overcomes the above given disadvantages, that is which can be easily set up for mastering and which is physically more strong than the simple bitted key.
Further, object of the invention is to provide an improved key with a reversible operation
ability.
Still further object of the invention is to provide an improved key which is pick resistant.
STATEMENT OF INVENTION
A locking system comprising; a pin tumbler lock having plurality of pin tumblers (18), the pin tumbler lock comprising: a shell (9) having a first slot (19) and second slot (21),a plug (8) being accommodated within the shell (9) through the first slot (19), the plug (8) comprises a key receiving slot (15) and a plurality of bores (20) for receiving the pin tumblers; a locking bar (14) being accommodated inside the second slot (21) of the shell (9), the locking bar (14) comprises a plurality of projections (25) adapted to be engaged with notches (24) of the pin tumblers (18), a pair of springs (17) to be located in a hole provided in the locking bar (14) for controlling movement of the pin tumblers (18); an orientation block (23) for accommodating the pin tumblers (18), and
a key for operating the pin tumbler lock through the key receiving slot (15) of the plug (8), the key comprising; a flat key blade (2) extending along a longitudinal insert axis,a front face having front angled edges (6 & 7), and a pair of side faces (5), the each side face having atleast one longitudinally extended groove (3) near the middle of the blade (2) in full length of the blade and having depth less than half of thickness of the blade and a plurality of angled grooves (4) having depth less than half of thickness of the blade transversely directed to the side faces extending through the edge of the blade on each side faces (5) positioned diagonally opposite edge of the blade,

wherein when the key is inserted in a key receiving slot (15) and rotated, the pin tumblers (18) slide freely with respect to the plurality of angled grooves (4) of the key (1) into the bores (20) of plug (8) and the orientation slot (23) by means of the springs (17) for locking purpose.
SUMMARY OF THE INVENTION
The key has according to the invention a flat key body having a blade extending along a longitudinal insert axis and having a front face formed with angled cutouts, an opposite longitudinally extending back edge and a pair of oppositely directed faces. Each face is formed with atleast one longitudinally extending front grooves adjacent the front edge a full length of the blade and having depths equal to less than half of a transverse thickness of the blade and an elongated angled groove extending transversely to the front face. The angled groove of the one face extends parallel to the angled groove of the other face, that is the axis of the angled grooves on one face are parallel to each other of the grooves on the other face. According to this invention the front groove closest to the back edge and the front edge are the same across an entire series of keys. Each face is formed in accordance with this invention with a plurality of such angled groove extending parallel to one another. More particularly, each face has pluralities of angled grooves. According to another feature of the invention, each of the angled groove ends in the edge face on the respective side and each side has a clear uninterrupted land extending along the insert axis.
Accordingly there is provided a key having a flat key blade extending along a longitudinal axis and having front face formed with angled cutout and a pair of side faces; each side face having atleast one longitudinally extended grooves near the middle of the blade in full length of the blade and having depths less than half of thickness of the blade and a multiplicity of angled grooves transversely directed to side faces extending through the edge of the blade on both side faces positioned diagonally on opposite edge of the blade.
BRIEF DESCRIPTION OF THE DRAWING
The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:
FIG 1 : Shows the elevation of the present invention.

FIG 2 : Shows the basic views of present invention.
FIG 3 : Shows the enlarged view of side view of present invention.
FIG 4 : Shows the enlarged view of bottom view of present invention.
FIG 5 : Shows the key assembly with cylinder of present invention.
FIG 6 : Shows the cross sectional view of the present invention along the line B B of present invention.
FIG 7 : Shows the cross sectional view along the line A A of invention.
FIG 8 : Shows the exploded view of the working lock for present invention.
FIG 9 : Shows the cross sectional view of the existing lock along the line AA
FIG 10 : Shows the cross sectional view of the existing locks along the line BB
SPECIFIC DESCRIPTION
As seen in FIG I to 4. a key (I) according to this invention has a flat blade (2) and key slot (3). The key blade (2) has a front angled edges (6) & (7) as well as oppositely directed and transversely extending side faces (5). Each side face (5) is fo"rmed with atleast one longitudinally extending groove (3) of uniform section and extending the full length of the blade (2) as well as plurality of angled grooves (4) extending transversely and opening in the edge face.
FIG 5 shows the lock for the key. According to this invention, which is basically cylindrical plug (8) rotatable in shell (9). The plug (8) has formed with passage (15) of similar cross section of the key to be inserted in to the plug (8) and the shell is provided with an axial groove (19).
The working of the key of present invention is as per the shown figure 5, 6, 7 and 8. This

consists of a pin tumbler lock comprising a shell, a plug within said shell, said plug rotatable by key means, the plug having plurality of bore means for receiving pin tumblers, the bore means being substantially normal to the axis of plug, shell having another slot means for receiving locking bar. Therein, the slot means being aligned with plug slot, means in the plug for forcing locking bar into shell slot means, and means for forcing the pin tumbler towards orientation block thereby misaligning the tumbler notches to prevent the locking bar entering within the notches, thereby projecting the locking bar into shell slot means, thereby preventing the plug rotation with respect to shell. The pin tumblers have notches to receive the locking block projection when aligned by keywards.
With reference to figure 5 to 8 which illustrates the present invention, the plug (8) comprises of slot (15) to receive key (I), blind bores (20), slot (21) normal to the bore, slot (22) along with the center line of the bores. The tumblers are forced by the spring (I I) towards the orientation block (23). This enable misalignment of tumbler notches (24) thereby preventing the locking bar projections (16) to move inside the tumbler notches (24). This avoids the plug rotation with respect to shell (9).
The shell (9) comprises of slot (21) adapted to receive the locking bar (14)
The key (I) comprises of projections (angled grooves) (4) of different variations.
The plug is rotatably retained in shell (9) by circlip (10)
The locking bar (14) comprises of projections (25) adapted to be engaged with notches (24) of pin tumbler (18) and holes to receive spring (17) which retains it against the slot (19) of shell (9) thereby allowing the pin tumbler (18) to slide with respect to projection (4) of key (I) freely into the bores (20) of plug (8).

WE CLAIM:
1. A locking system comprising:
a pin tumbler lock having plurality of pin tumblers (18), the pin tumbler lock comprising:
- a shell (9) having a first slot (19) and second slot (21),
- a plug (8) being accommodated within the shell (9) through the first slot (19), the plug (8) comprises a key receiving slot (15) and a plurality of bores (20) for receiving the pin tumblers;
a locking bar (14) being accommodated inside the second slot (21) of the shell (9),
the locking bar (14) comprises a plurality of projections (25) adapted to be engaged
with notches (24) of the pin tumblers (18),
a pair of springs (17) to be located in a hole provided in the locking bar (14) for
controlling movement of the pin tumblers (18);
an orientation block (23) for accommodating the pin tumblers (18), and
a key for operating the pin tumbler lock through the key receiving slot (15) of the plug (8), the key comprising:
a flat key blade (2) extending along a longitudinal insert axis,
a front face having front angled edges (6 & 7), and
a pair of side faces (5), the each side face having atleast one longitudinally
extended groove (3) near the middle of the blade (2) in full length of the blade and
having depth less than half of thickness of the blade and
a plurality of angled grooves (4) having depth less than half of thickness of the
blade transversely directed to the side faces extending through the edge of the
blade on each side faces (5) positioned diagonally opposite edge of the blade,
wherein when the key is inserted in a key receiving slot (15) and rotated, the pin tumblers

(18) slide freely with respect to the plurality of angled grooves (4) of the key (1) into the bores (20) of plug (8) and the orientation slot (23) by means of the springs (17) for locking purpose.

A LOCKING SYSTEM

Documents:

Inventors:

PCT Conventions: