Abstract:
A key mechanism that makes it possible to fix the key inside the cylinder bolt lock outphased from the original combination, thereby preventing the cylinder of the bolt lock from turning. The security of the key mechanism is also enhanced as a cylinder tumbler engages within a slot of the key blade and the key cannot then be expelled from the cylinder bolt lock. Therefore, it is impossible to insert another key or picklock from the other side of the cylinder bolt lock.

Description:
PRIORITY CLAIM 
     This application is based on and claims the benefit of priority from Mexican Patent Application No. MX/a/2009/002955 filed Mar. 19, 2009, the contents of which are incorporated by reference. 
     BACKGROUND OF THE INVENTION 
     Currently, the locking keys address different functions for securing a door by means of a lock with designs differing in the form and size of the key that is used, as well as the specific type of lock. This makes it necessary to have many different keys for locks, but at no time is the key a securing device for the lock, but only the means to obtain access to the locking and/or the unlocking of such lock. 
     In order to solve the problem of not having a mechanism where the same key also becomes a latch to secure the lock, the key mechanism of the invention fixes the key within the cylinder bolt lock in an incorrect position when so desired, so that the same key prevents the insertion of either another key or picklock into the cylinder bolt lock, as the cylinder gets blocked. This prevents the other key from turning the cylinder bolt lock and thus the key mechanism works as a locking device. In this way, the key mechanisms secure the key in an advanced or retarded position within the cylinder bolt lock, outphased from the proper combination, to prevent the cylinder bolt lock from unlocking when so desired. 
     It is important to note that if the bolt lock consists of two cylinders, one at the inside of the door and the other cylinder at the outside of the door, it is necessary that the key is pushed further into the inside cylinder bolt lock from the location beyond the proper combination, so that the tip of the key snaps and prevents the cylinder bolt lock on the other side from turning. If the cylinder bolt lock comprises a single cylinder, the key will be in a forward or retracted position to prevent synchronization of the tumbler bolts with the correct combination. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a key mechanism that is able to be fixed inside the cylinder bolt lock in a position outphased from the operational combination, so that the cylinder of the bolt lock cannot turn, and the key cannot be pushed out of the cylinder bolt lock from the other side. This prevents the input of any kind of key or picklock from the other side of the cylinder bolt lock. 
     The purpose of the present invention is to provide a security means different from the keys and locks already known, through the provision of a securing key. The key mechanism is the same and only key for the cylinder bolt lock which, upon being inserted into the cylinder of a conventional bolt lock to a position, the key mechanism unlocks and locks the cylinder bolt lock, and when inserted further to another position, the cylinder bolt lock is prevented from being unlocked. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view of the second key mechanism according to the invention. 
         FIG. 2  is an isometric view of the second key mechanism where the key blade is being inserted into the cylinder bolt lock. 
         FIG. 3  is an isometric view of the second key mechanism where the key is in the conventional locking or unlocking position. 
         FIG. 4  is an isometric view of the second key mechanism where the key is secured within the cylinder bolt lock, and cannot be pushed out of the cylinder bolt lock. 
         FIG. 5  is an isometric view of the second key mechanism where the key is freed from the cylinder bolt lock by actuation of the tumbler driver. 
         FIG. 6  is an exploded view of the first key mechanism according to the invention. 
         FIG. 7  shows top, side, bottom, isometric and back end views of the first key mechanism. 
         FIG. 8  is a side view and partial enlarged view of the first key mechanism where the key blade is entering the cylinder bolt lock. 
         FIG. 9  is a side view and partial enlarged view of the first key mechanism where the key is in the cylinder bolt lock at a conventional locking or unlocking position. 
         FIG. 10  is a side view of the first key mechanism where the key is in the locking or unlocking position with the T-latch pushed down. 
         FIG. 11  is a side, top and bottom view of the first key mechanism, secured to the cylinder bolt lock by a tumbler bolt of the cylinder bolt lock. 
         FIG. 12  is a side, top and bottom view of the first key mechanism, where the tumbler driver is actuated to lift the tumbler out of the slot so that the key can be removed from the secured position. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The key mechanism of the invention furthers the purpose of securing the cylinder bolt lock because it can be inserted into the cylinder of the bolt lock and fixed at such position where the proper combination is not achieved. This can be achieved by inserting the key into the cylinder bolt lock, be it either more than necessary or less than necessary, to prevent the correct combination within the cylinder. With this arrangement, the key mechanism will occupy the chamber or key slot of the cylinder bolt lock, thus preventing another key or picklock from being inserted from the other side and opening the cylinder bolt lock. The key also remains fixed in the cylinder bolt lock so it cannot be pushed out from the other side of the cylinder bolt lock. To prevent the securing key mechanism from being pushed out of the cylinder bolt lock, one of the combination tumblers of the cylinder bolt lock will fall into an opened slot of the key, thus securing the key and fixing it in a position out of the proper combination of the cylinder bolt lock, thus preventing the cylinder from turning. 
     The foregoing can be accomplished in several ways. Accordingly, two key mechanisms are proposed herein, consisting of several moving components which are coupled together. 
     Mechanism  1   
     The key mechanism  1  comprises ten moving components and three springs, where all the components are mounted on a mounting bracket. The first key mechanism includes the combination of the original key to unlock the cylinder bolt lock ( FIGS. 6 and 7 ). 
     
       FIGS. 8 and 9 
     
     These figures show how the butt end  5  of the key is locked by the T-latch  7  that has not been pressed down. The bolt driver  9  cannot be moved to form a slot because it is locked with the pin  4  which, in this position, is at the limit of the bolt driver slot (see partial view), preventing the bolt driver  9  from moving backwards.  FIG. 8  shows the key partially inserted into the lock  2 . 
     Upon inserting the key blade  3  in the cylinder bolt lock  2 , as shown in  FIG. 9 , it strikes with the butt end  5  of the key mechanism. In this position, the key unlocks or locks the cylinder like a conventional key. While not shown, the key blade  3  conventionally includes a unique combination of notches into which respective tumblers  15  fall for the correct combination to allow the cylinder of the bolt lock to rotate. 
     
       FIG. 10 
     
     Upon pressing the T-latch  7 , a portion thereof can enter into the butt end  5  so that the key blade  3  is free to slide a little more inside the cylinder of the bolt lock  2 , past the proper combination between the tumblers  15  and the notches in the key blade  3 . The key blade  3  cannot thus rotate the cylinder, even from the other side, if so desired. 
     
       FIG. 11 
     
     The securing action is accomplished when movement of the key blade  3  gets blocked by the tumbler  15 , which prevents removal of the key, thereby fixing it outphased from the correct combination, until the tumbler  15  is released by the tumbler driver  9 . The bottom spring  14  biases the key to return it back to its normal position, which is accomplished when the bolt tumbler driver  9  is actuated. 
     
       FIG. 12 
     
     Upon pushing the tumbler driver  9  toward the cylinder bolt lock  2 , the top spring  13  is compressed, the tumbler  15  is driven out of the slot, and the key is released. At this moment, the key can be pulled, whereupon the spring  14  returns the key back in place, the spring  11  returns the T-latch  7  back in place, restoring the limits of the normal key to open or close the cylinder bolt lock with the same key. 
     Mechanism  2   
     The key mechanism of  FIG. 1  comprises twelve components identified in the attached figures, illustrating the different positions of the key in the cylinder bolt lock  2 .  FIG. 2  shows the key partially inserted into the cylinder bolt lock  2 . 
     
       FIGS. 2 and 3 
     
       FIG. 2  shows the key partially inserted into the cylinder bolt lock  2 . Upon further inserting the key blade  20  into the cylinder bolt lock  2 , the butt  23  of the key strikes against the cylinder bolt lock  2 . This is shown in  FIG. 3 . In this position, the key unlocks or locks the cylinder bolt lock  2  like a conventional key. 
     
       FIG. 4 
     
     By pushing the key further inside the cylinder bolt lock  2 , after striking the butt  23 , the cylinder locking position is activated. The butt  23  is then fixed in place due to the spring  24 , while the mounting bracket  28  of the key moves further. This further movement of the key mounting bracket  28  rotates the lever  30  which pushes the key blade  20  further into the cylinder bolt lock  2 . 
     Upon pushing the key, a space or slot opens between the key blade  20  and the tumbler driver  22 , whereupon the cylinder tumbler  15  falls into the slot. This action blocks the key and prevents removal thereof from the cylinder bolt lock  2 . 
     
       FIG. 5 
     
     Upon pulling the mounting bracket  28  of the key, the lever  30  rotates in the opposite sense, pushing forward the tumbler driver  22 , thus lifting the cylinder tumbler  15 . When the cylinder tumbler  15  is lifted, the key is released and can be removed from the cylinder bolt lock  2 . 
     The first key mechanism ( FIGS. 6-12 ) comprises the following parts: 
     (1) Part of door: the part holding the cylinder-type bolt lock, 
     (2) Cylinder bolt lock: the key slot in the lock, 
     (3) Key blade: the part of the key having tumbler notches therein, 
     (4) Pin: limits movement of the tumbler driver, 
     (5) Butt end: engages cylinder bolt lock when the key is inserted into the cylinder bolt lock to lock and unlock it, 
     (6) Guide: for guiding the T-latch, 
     (7) T-Latch: fixes the key position when pushed down, 
     (8) Spring guide: guides the spring  11 , 
     (9) Tumbler driver: is moved to lift the tumbler out of the slot, 
     (10) Guide: guides the T-latch, 
     (11) Spring: applies spring bias to T-latch, 
     (12) Base: registers the key blade in the key housing, 
     (13) Spring: spring biases the tumbler driver and key blade, 
     (14) Spring: spring biases the butt end and the key blade, and 
     (15) Tumbler: part of the cylinder bolt lock. 
     The second key mechanism ( FIGS. 1-5 ) comprises the following parts: 
     (20) Key blade: part of key with combination notches to lock and unlock a cylinder-type bolt lock, 
     (22) Tumbler driver: drives the tumbler out of the slot in the key, 
     (23) Butt: abuts the cylinder bolt lock in the normal key position, 
     (24) Spring: allows operation of the tumbler driver, 
     (25) Guide pin: guides the spring  24 , 
     (26) Axle pins (three pieces): they allow operation of the lever, 
     (27) Spring: returns everything back to the normal key position, 
     (28) Mounting bracket: holds the components of the key, 
     (29) Key guide pin: guides the key, 
     (30) Lever: actuates the key mechanism, 
     (31) Key cover: covers the mounting bracket and components of the key, 
     (2) Cylinder bolt lock: part of the lock, and 
     (15) Cylinder tumbler: part of the cylinder bolt lock. 
     Having thoroughly described the invention, I consider it as a novelty and therefore claim as my sole proprietorship the contents of the following claims: