Deadbolt lock protector

A deadbolt lock protector including an outer metal enclosure, covering the lock, and attached to the door by means of non-removable screws. Inside the enclosure is a pin, formed of non-magnetic material such as brass, held alongside the thumblatch of the lock, preventing it from turning. The pin is held in that position by brackets and underneath by a support member. This support member's attachment is pivotable, and a cable is attached to it, so that from a remote position, the cable may be pulled, allowing the pin to drop out of the enclosure, in turn allowing normal use of the lock by means of a key. An extender straddles the thumblatch, so that the thumblatch can be turned from the inside of the door. The narrow portion of the extender, however, which passes through the enclosure, is relatively weaker than the pin, so that when the pin is in place, and the extender is forced, the extender will break before the pin.

BACKGROUND OF THE INVENTION 
This invention relates to security and protection from unauthorized entry, 
and in particular to protection from unauthorized entry into relatively 
unattended buildings through a door having a window portion. 
At the present time there is increasing interest in home security, 
especially considering the rising crime rate, particularly regarding 
crimes against property. In response to these increases, many people have 
installed improved lock systems and devices in order to further protect 
themselves. 
Many have chosen to install deadbolt locks because they believe that this 
type of lock provides the greatest physical protection from unauthorized 
entry. When this type of lock is installed on a door that is relatively 
unattended, such as the access door of a garage or other outbuilding, 
however, certain problems arise. When there are windows in that door, as 
is commonly the case, it is a simple matter for a burglar to break out a 
small portion of the window, reach inside, and turn the thumblatch, 
unlocking the door. 
Even in the case where the deadbolt lock is of the double cylinder type, 
the same danger exists. Experts advise that, in a garage or similar 
location, a key be kept near the lock so that is case of emergency an exit 
may be made quickly and safely. Hence again an experienced thief could 
break the window, find the key by feel, and let himself in with very 
little noise or disturbance. 
This invention relates to solutions to these problems. 
SUMMARY OF THE INVENTION 
This invention includes a protective metal enclosure to cover the portion 
of the deadbolt lock inside the door. Inside the enclosure are two 
brackets which hold a brass pin aligned so that the thumblatch of the lock 
cannot turn. The pin is supported by a spring-loaded stop which, by means 
of a shielded cable, can be moved remotely, allowing the pin to drop out 
through an aperture in the enclosure, thus allowing the thumblatch to be 
turned from the outside by the key. 
An object of the invention is to protect against unauthorized entry of a 
relatively unattended building, such as a garage. 
Another object of the invention is provide a relatively inexpensive and 
simple means to protect against unauthorized entry into a building. 
A more specific object of the invention is to provide an inexpensive and 
simple means to protect against unauthorized entry by means of breaking a 
window in the door and turning the thumblatch to unlock the deadbolt. 
Another specific object of this invention is to provide a simple and 
inexpensive means to protect against unauthorized entry, by means of a 
locking pin inside a protective enclosure. 
Other objects and advantages of the invention will appear hereinafter or be 
obvious.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to FIG. 1, a conventional single cylinder deadbolt lock is shown 
at 10, with a conventional thumblatch 12 shown in a vertical position 
corresponding to the lock 10 being locked. To unlock it, thumblatch 12 
must be turned away from the vertical. Lock 10 has a bolt 13 which is of 
the spring-loaded wedge type, so that the door can be locked simply by 
closing it when bolt 13 is in its protruding position. 
This invention includes an outer protective enclosure 14, shown partially 
cut away in FIG. 1. Enclosure 14 is a rectangular metal box, the walls of 
which are at least thick enough to make any attempt at forcible removal 
noisy and time-consuming. Preferred is heavy guage steel. The depth of the 
box is sufficient to cover lock 10 including thumblatch 12, while the 
height and width are sufficient to cover the lock and the internal 
components of the protector. 
Secured to the interior of enclosure 14 are two brackets 16 and 18, each 
having horizontal portions 16a and 18a. These horizontal portions have 
vertical holes 16b and 18b which are aligned with vertical holes 14a and 
14b in enclosure 14, one in the upper surface and one in the lower 
surface. Hence the four holes form a vertical line, which runs alongside 
thumblatch 12 when it is in its vertical position. 
Inserted into holes 16a and 18a is a pin 20, which is supported at its 
lower end by a support member 22, which in turn is pivotably attached to 
the lower edge of enclosure 14. The top end of support member 22, on which 
pin 20 rests, is angled, so that when it is leaning over in its support 
position, as shown by solid lines in FIG. 1, the top is horizontal. 
Support member 22 is also connected to an actuation cable 24, which is 
protected by a cover 26, such as a small pipe or cable sheath. 
As shown in FIG. 2, only enclosure 14 and cable sheath 26 are visible on 
the inside of the door 28. Sheath 26 leads down to the lower corner of the 
door 28, near the hinges. There cable 24 exits the sheath and leads over 
to a small aperture in the wall of the building, and through to the 
outside. As shown in FIGS. 2 and 3, an extender 36 is permanently placed 
through another aperture in enclosure 14. This extender 36 has a 
thumblatch portion outside enclosure 14, and two leg portions inside 
enclosure 14, which straddle thumblatch 12, one of the legs fitting 
between the side of thumblatch 12 and pin 20. The narrow portion of 
extender 36, between the thumblatch portion and the legs, is sufficiently 
soft that it will twist or break before pin 20 breaks. 
In operation, this invention serves to protect the deadbolt lock 10 from 
burglars in several ways. First, if the burglar attempts to gain entry by 
picking the lock, he will be prevented from doing so by pin 20, which 
stops thumblatch 12 from turning. If he then attempts to gain entry by 
breaking out a small portion of the window, as shown in FIG. 2, he is 
prevented from turning thumblatch 12 with his hand by enclosure 14. He is 
prevented from turning extender 36 by pin 20. If he attempts to force 
extender 36, such as with a tool, it will break as described previously, 
and he still will not have obtained access to the building. 
When the owner wishes to gain access, on the other hand, he simply pulls 
cable 24, which moves support member 22 out of the way, allowing pin 20 to 
drop out. He then uses his key to unlock the door, since thumblatch 12 is 
now free to turn. From the inside, he can still pull cable 24, at the 
lower left corner of the door, releasing pin 20, and then turn thumblatch 
12 by mean of extender 36. To lock the door again, he simply returns 
thumblatch 12 to its vertical position, drops pin 20 into position through 
hole 14a, and closes the door. Pin 20 is formed of brass or some other 
non-magnetic material so that an intruder cannot remove it through hole 
14a by means of a magnet. 
FIGS. 4 and 5 show the treatment of cable 24 on the outside of the 
building. In the embodiment shown in FIG. 4, a small "T" device 30 is 
attached to the end of cable 24, inside a small lockbox 32 bolted to the 
outside wall. Lockbox 32 covers "T" device 30 so that it cannot be 
accessed without a key. 
In the embodiment shown in FIG. 5, a lockbox 34 is recessed into the wall, 
in order to make it more difficult to attack the box itself in an attempt 
to gain entry. This arrangment provides somewhat greater security than 
that illustrated in FIG. 4, at a somewhat higher cost. 
While the apparatus hereinbefore described is effectively adapted to 
fulfill the aforesaid objects, it is to be understood that the invention 
is not intended to be confined to the particular preferred embodiments of 
deadbolt lock protector herein set forth, inasmuch as they are susceptible 
of various modifications without departing from the scope of the appended 
claims.