Safety lock

Invention patent for "Safety Lock" comprised by a mechanism (1) having a case composed of two parallel plates (2) interconnected by spacers (3), internally provided with an operating drive (4) for a latch bolt (5) and for a latch (6), this latter being also operable by means of a handle or alike, which passes through a corresponding opening (7), and, further, having a barrel block (8) incorporated in said mechanism (1) in transversal direction and being provided with a longitudinal hole or passage (9) which receives a puzzle barrel comprised by one or more rows of spring pin assemblies positioned radially with respect to two barrels (10) inserted in said passage (9), each of which has a cam configurating, eccentric and internal pin (11) which cooperates with the operating drive (4), said book (8) being retained within said mechanism by a drawer-like arrangement. The barrel block (8) is provided with a transverse channel (12) which houses cam (11) completely and leaves free a wide lower section (13), the side walls of channel (12) presenting small steps (14) along the upper edges, thereby defining guides (15) which are insertable in a corresponding aperture (16) of the said mechanism (1).

As it is generally known, there exist presently various types of locks, the 
majority of which comprising a mechanism containing internally a driving 
device for a locking bolt and a latch, said mechanism being controlled by 
a locking barrel located in a bedplate formed with a metallic block 
positioned transversely to the case, provided with a puzzle-barrel 
composed by one or more aligned rows of pins disposed radially with 
respect to the barrel or cylinder, which can be released using a 
corresponding key. 
The locks of this configuration, though being largely in use, present two 
great drawbacks as regards safety, one of them being the low resistance of 
the block or barrel to torsion, therefore being easily broken away with 
the use of a pipe wrench or similar tool. This occurs because the region 
located inside the lock's mechanism presents a very thin transversal 
section in order to allow rotation of a pulling cam for the driving 
mechanism which controls the latch and latch bolt, with the consequent 
weakening of that region. 
The other drawback featured by such locks of the prior art resides in that 
the barrel or cylinder is secured to the lock mechanism by means of an 
anchoring pin which penetrates into an orifice or thread provided that 
weakened region, so as to pivoting the barrel block transversally to the 
axis of the barrel block, being the only fixing means and which may be 
easily sheared by an impact applied lengthwise with respect to the block 
axis. 
Furthermore, there are also known some locks of the Yale type having a 
split barrel block and which present greater resistance to impacts, but 
they may be forced open by torsion as in the first case mentioned above, 
since the securing areas at the mechanism are small. 
Because of these drawbacks, and having in mind to solve them, it was 
developed the safety lock object of this invention, which features high 
resistance to forced collapsing, either by torsion of the block, or by 
impact, its construction form allowing that the block presents a 
transversal section of great area at the internal sector of the case, as 
well as providing a securing of the block by a drawer-like insertion, 
thereby obtaining a new concept in locks. 
The annexed drawings show the safety lock object of this invention, and in 
which:

According to what is being illustrated in the above Figures, the safety 
lock of the invention is constituted by a mechanism 1, having a case 
formed by two parallel plates 2 interconnected by spacers 3 and internally 
provided with an operating drive 4 for a latch bolt 5 and for a latch 6, 
this latter also being operable by a handle or the like (not shown) 
passing through the corresponding hole or opening 7, and, further, having 
incorporated to mechanism 1 a transverse barrel block 8 provided with a 
longitudinal hole or passage 9, and fitted with a puzzle barrel comprised 
of one or more rows of spring pin assemblies (not shown) radially 
positioned with respect of two cylinders or barrels 10 (not shown) 
inserted in passage 9, each of which having an eccentric internal pin 11 
configurating an interfering cam at the operating drive of latch bolt 5 
and the latch 6. 
By its turn, barrel block 8 is retained within the mechanism 1 by a 
drawer-like insertion, said barrel block 8 being provided with a 
transverse channel 12, so as to housing the control cam 11 completely, but 
leaving free a wide lower section 13. The lateral walls of channel 12 
present small steps 14 along the upper edges, defined as guides 15 to be 
inserted in the corresponding aperture 16 on mechanism 1. 
On the other hand, aperture 16 is in form of an elongated "U" disposed 
horizontally and into which the barrel block 8 is inserted, the guides 15 
of which forming abutment surfaces and receiving therebetween the upper 
edges 17 of aperture 16, thereby avoiding a movement of the barrel block 
in the direction of its longitudinal axis, while the steps 14 impede the 
same to rotate because they rest at the lower ends of edges 17, with the 
lower face of said barrel block 8 resting on the lower side 18 of aperture 
16. 
The safety lock so built up is mounted on any desired door by first 
positioning barrel block 8 thereat, inserting it in the corresponding hole 
provided therein. Next, the mechanism 1 is introduced by a drawerlike 
movement and, finally, screw 19 is tightened so as to pull barrel block 8 
by means of a threaded orifice existing on the same, until abutting the 
block against the vertical front side of aperture 16. Following this, 
fixing screws are bolted through orifices 21, what finishes the job. 
It is pointed out further that with the lock of the invention, screw 19 has 
the only purpose of positioning the barrel block; therefore, it is not 
subject to any stress and has no other function with respect to safety of 
the lock. 
The safety lock of this invention may, of course, be made with the most 
variable materials, in any other forms or disposition, without departing 
from the scope herein foreseen for patent protection.