Guard device for automobile ignition lock

The keyway of an automobile ignition lock can be protected by a key-shaped element which is secured by a combination lock to substantially preclude tampering with the automobile ignition lock. The guard device can be removed from the ignition lock keyway upon setting of the combination lock dials to the release position, and the regular ignition key can then be used with the ignition lock.

BACKGROUND OF THE INVENTION 
(1) Field of the Invention 
My invention is concerned with an improvement relating to an automobile 
ignition lock anti-tampering or similar lock protection or guard device. 
More particularly, my invention relates to a guard device for the keyhole 
or keyway of the ignition lock at the steering wheel column in cars, 
trucks and the like vehicles to preclude unauthorized use of the lock by 
blocking the ignition keyway. 
(2) Prior Art 
Various combination operated keyhole blocking devices have been made known 
in the prior art and including U.S. Pat. Nos. 3,732,711; 3,723,682; 
1,000,962; 942,537; 442,778; 145,865; and 119,851. 
Combination locks are keyless devices in which a number of dials or rings, 
inscribed with numbers or letters on the circumferential side or edge, are 
arranged in parallel on a central lock spindle. Selective rotation or 
turning of the dials until the correct combination has been established, 
will allow that the lock spindle can be brought into the position which 
allows opening of the lock, because the respective slots and other 
cooperating elements inside the rings with four rings or tumblers and 10 
numbers presents 10,000 possible combinations. 
However, there has remained a need for a combination operated keyhole 
blocking devices for automobile ignition locks to provide an economic and 
effective anti-theft or guard device which substantially precludes 
tampering with the respective ignition lock in which it is used. 
SUMMARY OF THE INVENTION 
In accordance with my invention there is provided a keyhole or keyway guard 
device for autombile ignition locks which comprises: a hollow handle 
portion or end; a combination lock means with the lock mechanism thereof 
including at least one main bolt, and with the mechanism being housed in 
the hollow handle portion or end; a hollow blade end unitary with the 
hollow handle portion and its interior in communication with the interior 
of said hollow handle portion; and a spring element operatively 
connectable to the main bolt of the combination lock mechanism. 
The spring element and the combination lock selectively interact in such a 
way such that the hollow blade end can be inserted into the respective 
automobile ignition lock, but it can then only selectively be taken out of 
the keyway of the respective automobile ignition lock by setting of the 
unlocking combination, thereby to allow actuation of the main bolt of the 
lock mechanism and to allow retraction of the spring element. 
In accordance with one aspect of my invention, the guard device has a 
combination lock means which includes four dials with 10 numbers. 
Thus, the invention contemplates a keyhole blocking or guard device which 
can be inserted with its blade end into the keyhole or keyway of an 
automobile ignition lock, and the spring element can assume the blocking 
or advanced position thereby to substantially preclude unauthorized use of 
the ignition of the respective vehicle. The device generally corresponds 
in shape to a key, but is formed with a hollow blade end. The spring 
element has a plurality of spring biased teeth formations, and it is 
movably disposed in the hollow blade. The spring element can be moved 
between the first, active or blocking, position and a second, inactive or 
retracted, position in conformity with the main bolt which, in turn, is 
housed in the hollow handle portion of the device and which main bolt is 
secured by a combination lock. When the combination lock has been set to 
open, the main bolt can be actuated to bring the spring biased teeth 
formation into the second, inactive or retracted, position, whereupon the 
guard or blocking device can be removed from the keyway. 
Included in the objects of my invention are: 
To provide an automobile ignition keyway blocking element or guard device 
which can be locked to preclude unauthorized use of the vehicle in which 
it is employed. 
To provide a simple yet effective anti-theft device for cars. 
To provide an combination lock guard device for automobile ignition keyway 
which device is economical in structure and manufacture.

SPECIFIC DESCRIPTION 
The keyhole blocking or guard device for automobile ignition locks is 
generally identified by reference numeral 10. It performs the function of 
an anit-theft device for the respective automobile ignition by being 
capable of blocking the keyway of the ignition lock, and its shape is 
generally analogous to that of a standard ignition key. 
The guard device 10 comprises a forwardly disposed hollow blade end or 
formation 11 and a rearward handle portion 12 which can have a key chain 
hole 13. The handle portion 12 is also hollow and houses the combination 
lock means, generally identified by reference numeral 14, of the guard 
device 10. 
The hollow blade end 11 can be readily inserted into the keyway of the 
respective automobile ignition lock (not shown), but it can only 
selectively be taken out of the keyway of the respective automobile 
ignition lock, with knowledge and setting of that combination which will 
allow actuation of the main bolt 15. The main bolt 15 is generally a round 
shaft or similar roller with an actuation pin 16 at its approximate 
center. The springs 17 and 18 respectively bias the ends 19 and 20 of the 
main bolt 15. 
In the described embodiment, the combination lock mechanism or device 14 
has four rings or dials 21, 22, 23, and 24, each having 10 digits arranged 
sequentially from "1" to "0" on the circumferential edge or face thereof, 
with the combination lock mechanism 14, accordingly, affording 10,000 
possible lock combinations. 
The main bolt 15 is provided with projections or lock formations 15a, 15b, 
15c and 15d, see particularly FIGS. 7 and 8. These lock formations 15a, 
15b, 15c and 15d, as well as the actuation pin 16 can extend through a 
retaining sleeve 25 which surrounds part of the main bolt 15, but which is 
otherwise formed with apertures or slots to allow functioning of the lock 
formations 15a, 15b, 15c and 15d and of the actuation pin 16. 
With particular reference to FIG. 6, the selected dial may be set at "1", 
the respective groove is then aligned with the respective lock formation 
to allow axial movement of the main bolt 15. Of course, when all dials 21, 
22, 23 and 24 are set in the correct combination, the main bolt 15 can be 
freely moved, but in accordance with the springs 17 and 18. 
The combination lock device 14 accordingly comprises a main bolt 15 
positioned transversely with respect the longitudinal axis of said hollow 
blade end 11, and the combination dials or rings 21, 22, 23, and 24 are 
operatively mounted about the main bolt 15. A chrome-plated push button 26 
which surrounds the end 20 of the main bolt 15 can be used to actuate the 
main bolt 15 when the locking mechanism 14 has set the main bolt 15 free. 
When inserted in the keyway and after obscuring the combination which will 
set the main bolt 15 free, the guard device 10 will substantially preclude 
unauthorized tampering with the lock, and particularly children will not 
be allowed to play with the ignition system, as will be described in 
greater detail below. 
The hollow blade end 11 has a length which corresponds substantially to the 
depth of the keyway of the automobile ignition lock. To fit the keyway, 
the hollow blade end 11 has an exterior keyhole groove 27 in its upper 
wall 28. The hollow blade end 11 also has a lower wall 29 with a further 
groove 30. 
A spring member 31 is positioned in the cavity 32 formed by the upper wall 
28 and the lower wall 29. The spring member 31 is generally V-shaped, with 
a first upper leg 33 and a second lower leg 34 which is shaped with 
several bent portions to present a plurality of tooth-shaped formations 
35. 
With particular reference to FIG. 5, the formations 35 are generally formed 
with a right-angle leg 35a. 
Thus, within the hollow blade end 11, there is provided the movable spring 
member 31, moveable due to its inherent elasticity and adapted to assume 
with its tooth-shaped formations 35 a first locking position whereby the 
formations 35 respectively engage the pins (not shown) of the ignition 
lock (also not shown) to guard the automobile ignition lock, by precluding 
operation thereof. 
Furthermore, the second lower end 34 of the spring member 31 has a length 
which is sufficient to be engaged by the actuation pin 16 of the main bolt 
15. Thus, when the main bolt 15 is free to be moved, the main bolt 15 can 
be shifted such that the actuation pin 16, in turn, moves the second, 
lower leg or end 34 of the spring member 31 until the tooth-shaped 
formations 35 are sufficiently clear of the pins of the ignition lock, and 
the guard device 10 can be pulled from the keyway. 
The operation of the guard device 10 is controlled by the combination-type 
lock means 14 which allows selective removal of the guard device 10 from 
the ignition lock keyway that it blocks, but knowledge of the combination 
to gain access for removal of the guard device 10 from the keyway is 
required. 
With particular reference to FIGS. 7 and 8, the lock formations 15a, 15b, 
15c and 15d of the main bolt 15, and the dials 21, 22, 23 and 24 are 
arranged in such a way that the lock formations are respectively 
positioned between the dials when the lock mechanism 14 is in the normal 
position. The position of the main bolt 15, the actuation pin 16, and the 
first leg 33 is then as is shown in FIG. 8. 
For removing the guard device 10, the push button 26 is depressed and the 
main bolt 15 is displaced such that the lock formations 15a, 15b, 15c and 
15d are respectively aligned with the dials 21, 22, 23 and 24, as is shown 
in FIG. 7. Correct setting of the dials will then allow removal of the 
guard device 10. 
It will be understood that the embodiment illustrated in the aforesaid is 
merely used for describing the present invention, but not as limiting the 
present invention. Any structure or apparatus made with or without minor 
modifications but not deviating from the spirit, concept and features of 
the present invention is deemed as being included in the scope of the 
claims of my invention.