Title of Invention


Abstract The hollow flimsy body of the existing padlock encloses a number of moving components comprising of the lock machine, locking latch and a shackle with a notch making the device even move vulnerable. With so much mechanical I movement within a structurally weak body, in the event of burglary, the shackle can be easily separated from the body. .. The Solution: The object ()f this invention is to provide a structurally solid body made from either pressed steel sheet, forged or fabricated. Here the lock machine, locking latch & shackle have their own independent nousings. The shackle instead of a notch has restrainers in the form of bayonet pins, catches or bulbous ends which directly interlock with corresponding slots in the solid body of the padlock. Thus, the locking latch is free of any tensile load applied.
Full Text

3. Description of Invention:
This invention relates to improvements in padiocte thereby creating
structurally stronger padlocks.
More particularly this invention relates to a improved lock for being used in place of known types of padlocks or detachable locks to ensure greater safety, reliability and security. These improved locks being structurally strong, cannot be wrenched apart using a crowbar for leverage.
The existing padlocks are flimsy in construction as the outer body is made from sheet metal of less than 1.5 mm thickness. Further, it has an internal core (made from sheet metal, zinc and aluminum die cast components) which supports the lever mechanism, locking latch movement that engages and releases the shackle. Further, the shackle too has its bearings within the body of the padlock. With so much mechanical action taking place in the semi-hollow body, being weak, it becomes vulnerable in the event of a burglary and the shackle can bo wrenched apart from the body by means of a crowbar using the body as leverage.
To add to these design flaws the sftackfe has a groove (to engage the locking latch) which weakens the padlock further.
For obvious reasons the thicker the shackle the more secure the lock is considered to be. As can be seen in the existing padlocks the overall dimensions of the body increases in proportion to the shackle diameter, thus for a padlock with a mere 13.0 mm dia. shackle (the thickest available in the market) the length of the padlock is a whooping 123.0 mm with a thickness of 31,0 mm. Apart from pushing up the manufacturing cost the purpose is not served as 50% of the shackle dia. is milled to form the groove thereby only serving only to weaken the shackle and afford only 50% of its rated strength.
To add to the aforementioned design flaws the breaking of the free end of the shackle with the two grooves (in the double locking system) is easy as even here one end of the shackle is unsupported and yields due to the stress concentration in the said groove.
Manufacturers of padlocks claim that their padlock is equipped with precision 8 levers and the latest pin tumbler technology and that the same is pick proof. From the foregoing, it is obvious that the provision of a large number of

precision levers and other electronic and sophisticated locking means makes it only difficult for any one to prepare duplicate keys and other means and it does not necessarily make the lock difficult for culprits to wrench and tear open by means of crowbars and other implements.
It is also a known fact that it is easier to break open the locks than prepare duplicate keys which is time consuming and requires great skill.
In any burglary attempt time for successful completion of a job is a crucial factor and no burglar will attempt to duplicate the key on the spot as it is a time consuming factor and he is under tremendous pressure for fear of being caught in the act. Here brute strength and leverage used to wrench open and separate the vulnerable shackle from the vulnerable body is the vital requirement.
No doubt the locking means comprising of fevers and pin tumfoters are reliable and safe (as it is difficult and time consuming to duplicate the key) as such to make the padlock wholly safe, secure and reliable it is of paramount importance to obviate these design flaws in the first place.
To sum rt up of what use are sophisticated tacking means when the body itself suffers from the aforementioned design flaws?
it is to be clearly understood that the expression 'locking means / lock machine' wherever appearing throughout ttie specification is intended to mean and include any 'key and lever operated', key and pin-cylinder operated, key and pin tumbler operated, combination number operated, magnetic key operated, electronic, remote controlled and other devices. Likewise ttie expression 'locking latch' where ever appearing throughout the specification is intended to mean and include locking pins, bolts, latches, spring tensioned pawls, clicks or saw teeth operated by key, number or electronic means.
The principle object of this invention is to provide it}^ improved padlock with a solid strong body that can withstand severe torsion, tensile and angular forces it is subjected to in the event of a burglary.
Further object of this invention is to provide the shackle with restrainers in the form of bulbous ends, catches or bayonet pins, which directly interlock with the solid body of the padlock. This way, the provision of a vulnerable notch, which weakens the shackle is eliminated.

A further object of flits invention is to make die locking latch operate in a housing of its own and deadlock die shackle when desired, litis way in the event of a bursary no tensile force acts on fchelocMng latch.
Yet another object of this invention is to provide the shackle with a firm support and guide from outside die housing of die locking means /lock machine.
A. further object of this invention is to provide theiocking means / lock machine wi&i a strong indep en dent housing of its own.
For better under standing this invention will" beillustrated by way of example with reference to the accompanying drawings in which;
Figure 1; Shows die sectional front elevation of a conveatio&al double locking padlock with die locking latch engaged in the vulnerable notch of die shackle.
Figure I a; Shows a part see tional front elevation of the conventional padlock as shown in fig.l ? where both die end£of die shackle crack under die tensile force applied in die direction oi die arrowf inarkedUlterait].
Figure 2, Shows one end of die shackle with a bulbous portion.
Figure 2 a, Shows the sectional view through A- A of the shackle as sem in figure 2,
Figure 2b , Shows the modified shackle [as seea in Figs, 2 & 2aJ engaged to a solid body having corresponding slots 10a & 10b 3 -
Figure 3. Shows a shackle having bayonet pin projections [forged frcwi the paren t material itsdf)
Figure 3a. Shows the sectional view through B - E of the shackle having bayonet pin projec (ions as seen in figure3.
Figure 3b. Shows a part of the solid body with corresponding slots to engage die bayonet pins.
Figures 4^4a &4h; Show a shackle with a circular gjroove engaging a solid body with' a corr esp onding siot 10 a.
Figure 4c* Shows the solid body with siotsflOa & 10b]corr esp onding to that of the groove hi the shackle.
Figure 4d.. Shows a shackle having bulbous aids with a transverse hole to deadlock the shackle.
Figure 4e» Shows the shackle interlocked to the solid body and the locking latch engaged to the hole in the shackle and deadlocking die same.

Figure;4f; Shows the plan view of the same padlock as seen in figs 4d &
RefefFing to figures 1 ami 19 offfw &wmpMf^ drawings W a awtoar (not shown) is passed through the shackle 1 of a conventional double locking padlock 2 and is pressed downwards with full weight of the body, due to the multiplied force the padlock yields at two points (i) as the end of the locking latch 3, which is engaged in the notch 4 of the shackle 1, is unsupported and freely floating, due to the tensile force (see arrow mark] acting on the shackfe 1 the latch 3 has no other go but to bend along the direction of the force resulting in the release of the shackle and (ii) with nearly 50% of the metal removed to form the notch 4 the end of the shackle 1 is weakened. Thus even if the locking latch 3 can hold on, the entire force falls on the end of the shackle 1 which gives way, due to the stress concentration in the edge of the notch 4, thereby releasing the shackle 1. In a recent burglary it was observed that three of the best makes of padlocks had yielded in the aforesaid manner due to the use of crowbars and other implements by the culprits. Needless to say, it can be seen that with the existing method of locking the shackle to the body of the padlock, no matter how complicated, sophisticated and pick proof locking mechanism is employed to operate the locking, latch 3 the padlock 2 becomes useless in the event of a burglary. Further big sized padlocks are used in places where maximum security is called for, but ironically, they are provided with bigger shackles to permit them to be hooked into staples of varying thickness and which easily permits the entry of 2 or even 3 crowbars thus making the job of breaking open such padlocks much easier for the culprits.
To begin with the vulnerable notch 4 in conventional padlocks has to be eliminated for aforementioned reasons. Here the notch 4 is replaced by more reliable and sturdy methods with restrainers in the form of bayonet pins, bulbous ends & catches to directly interlock with the solid body in the manner explained in the following description;
Refer Figure 2 & 2a; Here the modified shackle has bulbous ends forged from the parent material itself. Fig.2a shows the sectional view through A-A.
Refer Figure 2b; Here the modified shackle 1 interlocks with a solid body 12 and can swing about its axis in one limb which is retained in position by means

>f retainers 16.
Refer figure 5 & $a; Here the modified shackle 1 is provided with bayonet pin rejections 7while figure 3a shows die sectional view through B -B„
BLefer figin-e3h;Showsapartof the solid body 12 having corresponding slots 10a & Wfc to engage die bayonet pin projections 7.
Refer figure 4. Here diemodified shackle 1 engages the slot 10ain solid body 1
BLefer figure 4a; Shows tiie plan view of die modified shackle lintarlocking widi body 12.
Refer figure 4b; Shows the end view [front] of the shackle 1 interlocking with, die body 12,
Refer figare 4c; Shows the solid body 12 with slots 10a & 10b corresponding to the shape of themodified ends of shackle 1.
Refer figure 4d; Here the modified shacMe 1 has a transverse slot 18 to engage die locking latch [not shown].-"-"
■::""- ■■*•'■" '•■..'■ ^ .-■.' '
Refer figare 4e; Shows die solid body 12 of diepadiockinterlocked to die modified shackle LHcre die locking latch 20 {housed in its housing 21] moves to engage the transverse slot IS when tlielocldngmeaiis/lockmachhieis operated.
Refer figure4f; Shows die plan view of die improved padlock where onelimb of die
shackle 1 is pivoted atpoint C and can swing horizontdlyjsee direction of arrow] to engage with its corresponding dot 10a atits odier end.
Themediod of deadlocking the shackle to die solid body of die padlock can be varied to suit various types ofioc&ng means presently available and also accommodate possiblevanaSonsin latere. As such to serve asm example die lock machine and themaiuier in which dielockinglatch engages the slot in die shackle to enable the same to get deadlocked is &own only in figures 4e and 4f.
L Hie modified shacJde with restraints engage direcfly wi& die solid body of (he padlock.
Here die shackle swings to interlock with its corresponding slot in die soM body of die padlock in die horizontal plane.

2. The deadlocking of the shackle takes place outside the housing of the
locking means.
3. The tensile force, during a burglary attempt, does not act on the locking
latch Directly. The restraints on the shackle end bear the brunt of the
attack. Here the locking latch only serves to deadlock the shackle to the solid body and prevent it from turning on its axis and get disengaged. The tensife force, here, acts along the axis of the shackle and the stress is distributed over a larger area. Here the locking latch reciprocates in a solid housing of its own.
4. The locking means has a solid housing of its own.
However, as may be noted, the foregoing description and drawings is only Illustrative and the configuration of the various parts I.e. the shape of the bayonet pins, catches and the bulbous ends & the manner of their engagement/Interlocking with the shaped slot/profile on the body of the modified padlock to which they are to be adapted and the manner In which the Interlocking parts are deadlocked can be varied In many ways without departing from the scope of this invention.

1. a padlock comprising of a solid body [12] having two slots [10a and 10b]
which interlock with two ends of the shackle |1| of corresponding shape in such
a manner that the tensile force , when c%ertedfis directly borne by the two
interlocked shackle ends and solid body [1 {; characterized in that one end of
the shackle [1 j is pivoted [at point CJ while its other end is turned about in
the horizontal plane to interlock with its corresponding slot 10a; here the lock
. machine (22)* shackle (1) and locking latch (20) have independent housings which are integral with the said solid body 12; the arrangement being such that on operating the lock machine (22) the locking latch (20), (one end of which is linked to the lock machine (22),) moves to deadlock the shackle (1) with it*s other end in such a manner that the deadlocking takes place outside the housing of the lode machine (22);
2. a padlock as claimed in claim 1 where the two ends of the shackle [1] can be
bulbous or have bayonet pin projections or a circular groove so as to interlock
with corresponding slots 10a and 10b in the said solid body [12] directly ;
3. a padlock as substantially hereinbefore described and illustrated with
reference to the accompanying drawings


710-mas-2002- abstract.pdf

710-mas-2002- claims duplicate.pdf

710-mas-2002- claims original.pdf

710-mas-2002- correspondence others.pdf

710-mas-2002- correspondence po.pdf

710-mas-2002- description complete duplicate.pdf

710-mas-2002- description complete original.pdf

710-mas-2002- description provisional.pdf

710-mas-2002- drawings.pdf

710-mas-2002- form 1.pdf

710-mas-2002- form 4.pdf

710-mas-2002- form 5.pdf

Patent Number 207529
Indian Patent Application Number 710/MAS/2002
PG Journal Number 44/2007
Publication Date 02-Nov-2007
Grant Date 14-Jun-2007
Date of Filing 24-Sep-2002
Name of Patentee NEETHALA MITTU
Applicant Address #267/79V 8TH CROSS , JAKKAPPAN NGAR,KRISHNAGIRI-635 001.
# Inventor's Name Inventor's Address
PCT International Classification Number E05B67/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA