Abstract:
A combination lock and locking pin is provided which includes indexed tumblers operable in any sequence or simultaneously to enter a combination, a channel to protect the locking pin, and a locking pin with nested locking cylinders or a reduced or conical shaped nose to fit different sized latch plates or the area behind a gun trigger.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a combination lock, and more particularly, to a combination lock which may be opened without viewing the lock and which includes a variable-sized shackle. 
     Combination locks are well known in the art. A combination lock typically includes a body, which includes tumblers, locking members and a combination dial. Extending from the body is an inverted U-shaped shackle with one leg slightly shorter than the other leg, which is engaged with the locking members to latch and release the shackle relative to the lock body. When released, the shackle moves upwardly out of the body to achieve relative reciprocal movement. The short end of the shackle will then pivot to open only after vertically clearing the lock body. One problem with these types of reciprocating shackle combination locks is the shackle is exposed and thus easy to cut using bolt cutters or other tools. Another problem with these types of locks is the combination dial must be viewed in order to enter the combination and open the lock. If the lock is in a position in which the dial is not visible or if it is dark, the lock is difficult to open. 
     Another type of lock well known in the art is the gun lock or gun trigger lock. The detachable gun lock typically includes a back plate with a post which extends through the trigger guard of the gun in front of the trigger, and a combination or key actuated bolt which cooperates with the post to secure the post between the trigger guard and the trigger. A problem with the dial combination gun lock is in an emergency it may take several attempts to correctly enter the combination and open the lock. If it is dark or if the gun owner requires corrective lenses to be able to see and is not wearing them, the dial may not be readily seen. This problem is especially difficult at night when the gun owner is awakened by the sound of an intruder. The gun owner may not want to turn on a light in order to read the combination dial. Another problem with gun trigger locks is the lock is often clamped to the trigger guard with pressure. If the friction between the lock and the trigger guard is overcome, the trigger may be pulled and the gun fired if loaded. With a key-actuated trigger lock, if the key is located, anyone may open the lock and use the gun. Conversely, if the key is lost or cannot be located in an emergency, the lock cannot be opened when necessary. 
     SUMMARY OF THE INVENTION 
     The present invention provides a combination lock which may be used in place of prior art shackle locks and gun locks. The combination lock includes indexed tumbler buttons to enter the combination without having to view the lock. A variable-sized locking pin is protected within the protective housing and occupies the space behind a trigger on a gun or the eye of a latch plate. The tumbler buttons may be activated separately or simultaneously in any sequence to operate the combination lock. 
    
    
     Other advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example, a preferred embodiment of the present invention. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the combination lock of the present invention. 
     FIG. 2 is a front elevation view of the combination lock of the present invention in the locked position. 
     FIG. 3 is a front elevation view of the combination lock of the present invention in the unlocked position. 
     FIG. 4 is a side elevation view of the combination lock of the present invention. 
     FIG. 5 is a perspective view of the combination lock of FIG. 1 with the front cover removed. 
     FIG. 5 a  is an enlarged view of a tumbler button structure of FIG.  5 . 
     FIG. 5 b  is an enlarged view of a reset button structure of FIG.  5 . 
     FIG. 6 is a front elevation view of the combination lock of FIG.  5 . 
     FIG. 7 is a sectional view of the combination lock of FIG.  4 . 
     FIG. 8 is a sectional view of a housing with the components removed. 
     FIG. 9 is an enlarged perspective view of the tumbler shaft assembly. 
     FIG. 10 is an enlarged front perspective view of a tumbler. 
     FIG. 11 is rear perspective view of the tumbler of FIG.  8 . 
     FIG. 12 is an enlarged perspective view of a reset spring. 
     FIG. 13 is an enlarged side view of the tumbler shaft. 
     FIG. 14 is a side view of the tumbler shaft of FIG. 13 rotated ninety degrees. 
     FIG. 15 is an enlarged side elevation view of the retaining latch. 
     FIG. 16 is an enlarged perspective view of the tumbler button assembly. 
     FIG. 17 is an enlarged perspective view of the tumbler lock and reset assembly. 
     FIG. 18 is an exploded view of a nesting locking pin. 
     FIG. 19 is an exploded view of a tapered locking pin. 
     FIG. 20 is a front elevation view of the combination lock of the present invention engaged with a revolver. 
     FIG. 21 is a side elevation view of the combination lock of the present invention engaged with a revolver. 
    
    
     DETAILED DESCRIPTION 
     Referring to FIGS. 1-4, an illustration of the combination lock of the present invention is generally indicated by reference numeral  20 . Combination lock  20  includes a housing  22 , with a front  24  cover and back cover  26 . Covers  24  and  26  are each secured to the housing  22  by four fasteners  28 . One side of housing  22  includes four indentions  30 , which are shaped to accommodate the four fingers of a hand when gripping the combination lock  20  in either hand. Four tumbler buttons  32  extend from housing  22  and are centered in the indentions  30 . Opposite indentions  30  is a reset indention  34  with a reset button  36  extending from housing  22  (FIGS.  2  and  3 ). A locking pin  38  extends across a channel  40  in housing  22  when in the locked position (FIGS. 1 and 2) and locking pin housing  124  extends from housing  22  when in the unlocked position (FIG.  3 ). Channel  40  is sized to accommodate the eye of a latch plate or the trigger guard of a gun, for example. Combination lock  20  may be used with either the left or right hand. 
     Referring to FIGS. 5 and 6, housing  22  includes a cavity  42  in which the components of lock  20  are contained. Included in housing  22  is a tumbler shaft assembly  44 , a tumbler button assembly  46 , a tumbler lock and reset bar assembly  48 , and a locking pin assembly  50 . The tumbler button assembly  46  drives tumbler shaft assembly  44  through operation of tumbler buttons  32 , and is retained in housing  22  by tumbler button retaining cover  52  (FIG.  7 ). Tumbler lock and reset bar assembly  48  holds each tumbler  54  in an indexed position determined by the number of tumbler button  32  presses. When reset button  36  is depressed, tumbler lock and reset assembly  48  releases tumblers  54  to return to the reset position. Tumbler lock and rest bar assembly  48  is held in housing  22  by tumbler lock and reset bar assembly retaining cover  55  (FIG.  7 ). 
     Referring to FIGS. 9-15, the tumbler shaft assembly  44  includes a shaft  56 , four spaced-apart tumblers  54 , and a retaining latch  58 . Tumbler  54  (shown enlarged for detail in FIGS. 10 and 11) includes an index gear  60 , which has nine teeth corresponding to nine rotational positions. An index notch or keyway  62  on the inner circumference of index gear  60  extends coaxially with the axis of rotation of tumbler  54 , through tumbler base  64  is shaped to allow key tabs  66  (FIGS. 13 and 14) to freely pass through tumbler  54  when the correct combination is entered or when the lock is set. A zero-position aperture  68  (shown with zero position pin removed) marks the zero or reset position of tumbler  54 . When the combination lock is reset, all tumblers rotate about shaft  56  to return to this position. 
     Reset spring  70  (shown enlarged for detail in FIG. 12) is formed from a coiled piece of spring steel with a cylindrical first end  72  adapted to engage a semi-circular notch  74  in index gear  60 , which extends coaxially with the axis of rotation of tumbler  54 . The other end  76  of spring  70  is bent at a generally right angle and radially inwardly to the center of spring  70 . The bent end  76  of spring  70  is adapted to engage slots  78  spaced along tumbler shaft  56  (see FIGS.  13  and  14 ). When reset spring  70  is installed in a tumbler  54  and the tumbler  54  is placed on the tumbler shaft  56 , the tumbler  54  may rotate from a starting or zero position around shaft  54  and return to the starting position by the reset spring  70  which is anchored to the shaft by the bent end  76  inserted into slots  78  and attached to the tumbler  54  by the cylindrical end  72  inserted into notch  74 . The slots  78  are long enough to allow tumbler shaft  56  to slide to the released position. 
     Tumbler shaft  56  (shown enlarged for detail in FIGS. 13 and 14) includes an aperture  80  at one end adapted to receive retaining latch or latch dog  58 . A retaining pin  84  passes through a pair of radially aligned slots  86  in shaft  56  through a hole  106  in the end of retaining latch  58  to secure retaining latch  58  within aperture  80 . The retaining pin  84  and slots  86  allow retaining latch  58  to reciprocate within aperture  80 . A spring (not shown) at the base  90  of aperture  80  biases retaining latch  58  outwardly from the end of shaft  56 . 
     Retaining latch  58  (shown enlarged and removed from shaft  56  in FIG. 15) includes a latching head  102  and a latch post  104 . Aperture  106  through the end of post  104  opposite head  102  receives pin  84  to slidably secure retaining latch  58  within aperture  80  of shaft  56 . 
     Tumbler button assembly  46  (shown enlarged and removed from housing  22  in FIG. 16) includes a cylindrical tumbler button  32 , which extends from housing  22 . Button  32  is held in housing  22  with a retaining pin  92  which passes through an aperture  94  in tumbler button  32 . Tumbler button spring  96  biases tumbler button  32  outwardly from housing  22 . When a button  32  is depressed, spring  96  is compressed and then returns the button to the starting position. Button  32  includes a slotted end  98  to receive a flexible blade  100  which engages the index gear  60  of tumbler  54  to incrementally rotate tumbler  54  around shaft  56 . Each time a button  32  is depressed, the blade  100  engages the index gear  60  to rotate tumbler  54  about tumbler shaft  56  one notch of the gear  60 . 
     Tumbler lock and reset bar assembly  48  (shown enlarged an removed from housing  22  in FIG. 17) includes reset button  36  with a chamfered end  108 , reset spring  110 , reset bar  112 , and tumbler lock bar  114 . Reset bar  112  is slidably mounted in housing  22  and moves between a tumbler lock position and a reset position. Reset bar  112  includes three fingers or guides  116  which help the reset bar  112  maintain its alignment with respect to the tumblers  54  when moving between the lock and reset positions. Tumbler lock bar  114  is secured to reset bar  112  using rivets, machine screws, or other fasteners  118 . Tumbler lock bar  114  includes four lock fingers  120 . When the tumbler lock and reset bar assembly  48  is in the lock position, the four lock fingers  120  engage the index gears  60  of tumblers  54  to prevent the tumblers  54  from rotating in the clockwise direction. When reset button  36  is depressed, which moves the tumbler lock and reset bar assembly  48  to the reset position, the four lock fingers  120  of tumbler lock bar  114  are moved away from the index gears  60  of tumblers  54  which allow the reset springs  70  to return the tumblers  54  to the starting position. The chamfered end  108  of reset button  36  is adapted to engage a chamfered or angled notch  122  in tumbler shaft  56 . 
     Referring to FIG. 18, a nesting locking pin  38  is illustrated in an exploded view. Nesting locking pin  38  includes a housing  124 , a plurality of expansion cylinders  126  which are biased outwardly from housing  124  by a plurality of springs  128  against button  130 . A retraction spring  132  biases the nesting locking pin housing  124  outwardly from the combination lock housing  22  (FIG. 3) to retract locking pin  38  from channel  40  when the combination is correctly entered and the lock released. Lock button  120  includes an expansion locking pin  134  which extends across channel  40  with cylinders  126 . The nesting locking pin  38  completely fills the hole of the unit being locked, up to the outer dimension of the nesting locking pin  38 . Once the lock is engaged, the nesting locking pin  38  becomes a solid unit with the unit being locked. 
     Referring to FIG. 19, a reduced locking pin  140  is illustrated in an enlarged and exploded view. Reduced locking pin  140  includes a housing  124 , a cone-shaped tip  144  which is outwardly biased from housing  124  by spring  146  against button  148 . Button  148  includes a hollow expansion push pin  150  and a taper pin  152  which extends through tip  144  and engages hallow expansion push pin  150 . A retraction spring  132  biases the reduced locking pin housing  124  outwardly from the combination lock housing  22  to retract locking pin  140  from channel  40  when the combination is correctly entered (see FIG.  3 ). 
     The cone  144  is pushed through the opening  40  of the lock housing  22  and through the opening of the unit being locked until cone  144  engages the outmost perimeter of the hole in the unit being locked. Shaft  150  of button  148  keeps extending through cone  144  until expansion pin  152  is engaged by the opposite side of channel  40 . At this point expansion  152  is fully extended into shaft  150  solidly engaging cone  144  into a locked position. Expansion pin  152  is locked and held into place by expansion and friction. Cone  144  is locked in position by lock tab  125  which is engaged with retaining latch  58 . If cone  144  pushes all the way through the unit being locked, cone  144  engages recess  39  in housing  22 . Once disengaged, springs  146  and  132  push locking pin  38  out of lock channel  40 . 
     Referring to FIGS. 5-8, internal views and cross sectional views of the combination lock  20  and housing  22  are shown. Tumbler shaft assembly  44  is positioned within cavity  42  of housing  44  between spaced-apart upper and lower guides  160 , which receive each tumbler base  64  therebetween. Tumblers  54  rotate counter clockwise around shaft  56  in response to a depression of one of the tumbler buttons  32 . The motion of tumbler button  32  is transferred to the tumbler gear  60  by blade  100 . Each of the tumblers  54  may independently rotate about shaft  56  driven by tumbler button assemblies  46  until the keyways  62  of all tumblers are aligned with shaft keys  66  or zero position pin (not shown) encounters stop pins  162 . If all the keyways  62  of all tumblers  54  are aligned with shaft keys  66 , the shaft  56  is pulled through each of the tumblers  54  by shaft release spring  164  attached between housing  22  and pull-down pin  166  secured to shaft  56 . When the shaft  56  is pulled-down, shaft latch  58  releases locking pin  38  (or  140 ) to unlock combination lock  20 . 
     To reset lock  20 , reset button  36  is depressed. Chamfered end  108  of reset button  36  engages notch  122  in shaft  56  to lift shaft  56  to the reset position. When keys  66  clear the tumbler bases  64 , the tumblers  54  rotate clockwise by spring  70  to the reset or zero position. Release latch  58  is now in position to engage locking pin housing latch  125 . 
     Referring to FIGS. 20 and 21, combination lock  20  is shown in use as a gun trigger lock attached to gun  200 . Trigger guard  202  of gun  200  is inserted into channel  40  of combination lock  20 . Nested locking pin  38  is extended across channel  40  behind trigger  204 . The entire space behind trigger  204  is filled by locking pin  38 . To open combination lock  20 , tumbler buttons  32  may be pushed in any order or simultaneously to the preset combination. 
     For example, if the preset combination is  2635 , the first tumbler button  32   a  may be pushed twice, followed by the second tumbler button  32   b  being pushed six times, followed by the third button  32   c  being pushed three times, and finally the last tumbler button  32   d  being pushed five times. Another way the combination lock  20  may be opened is by activating all buttons twice, buttons  32   b ,  32   c , and  32   d  a third time, buttons  32   b  and  32   d  fourth and fifth times, and button  32   b  a sixth time. In this manner combination lock  20  may be opened very quickly without looking at the lock. It should be appreciated that by eliminating the need to visually look at the combination lock  20  in order to unlock it, combination lock  20  may be effectively used in the dark or in low lighting environments, or in positions where the lock may be partially or totally obscured from direct vision. 
     When used to lock a gun, the locking pin will fill the space between the trigger  204  and trigger guard  202  of most guns. In the case of a semiautomatic gun, the lock  20  will fit in front of the trigger with the trigger pulled pressing the trigger all the way back into the gun housing rendering the gun unable to be fired. 
     It should be understood that while a certain form of this invention has been illustrated and described, it is not limited thereto except insofar as such limitations are included in the following claims.