Patent Publication Number: US-2021189766-A1

Title: Hook lock with dual locking function with key captive design

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application No. 62/949,543, filed Dec. 18, 2019, which is incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     The present invention relates to locks, in particular a hook lock that can be unlocked by a combination mechanism or by an overriding key mechanism. 
     BACKGROUND OF THE INVENTION 
     The present invention is a hook lock with a dual locking function enclosed in a lock body/housing. The hook lock can be opened by a combination mechanism or by an overriding key mechanism. The key mechanism to override the combination mechanism, like that in many Transportation Security Administration (TSA)-compliant luggage locks, allows a TSA agent to open the lock with a key. 
     SUMMARY OF THE DISCLOSURE 
     The hook lock has a hook and a locking finger. The locking finger is engaged with the hook when the lock is operated in the locked mode. The locking finger is disengaged from the hook when the lock is operated in the opened mode. The hook lock can be opened by a combination mechanism or by an overriding key mechanism. The combination mechanism has a plurality of dials with indicia to form a correct combination to open the lock. The key mechanism has a cylinder with a key slot to receive a correct key. The cylinder must be rotated to open the lock. After the lock is opened with a key, the cylinder cannot be rotated back to its initial position before the locking finger is pushed back to engage with the hook. This key-captive feature ensures that the lock will be put back to the locked position after the key-user opens the lock. Thus, it is an aspect of the present invention to provide a hook lock, operable in a locked mode and in an opened mode, said lock comprising: 
     a lock body having a first body portion and a second body portion; 
     a hook located in the first body portion; 
     a locking finger pivotally mounted in the first body portion in relationship to the hook, the locking finger operable in a first finger position when the lock is in the locked mode, and in a second finger position when the lock is in the opened mode; 
     a combination mechanism located in the second body portion; 
     a latch operable in a first latch position and a second latch position, wherein when the latch is in the first latch position, the locking finger is prevented from moving from the first finger position to the second finger position, and when the latch is in the second latch position, the locking finger is allowed to move from the first finger position to the second finger position; 
     a button located in the first body portion in relationship to the combination mechanism, the button operable in a first button position and a second button position, wherein when the button is caused to move from the first button position to the second button position, the latch is caused to move from the first latch position to the second latch position. 
     In an embodiment of the present invention, the latch comprises a latch tip and the locking finger comprises a cutout dimensioned to receive the latch tip when the latch is in the first latch position, and when the latch is caused to move from the first latch position to the second latch position, the latch tip is disengaged from the cutout, allowing the locking finger to move from the first finger position to the second finger position. 
     In an embodiment of the present invention, the combination mechanism comprises a spindle having a longitudinal axis, the spindle comprising a first spindle end and a second spindle end, the first spindle end having a contact surface positioned in relationship to the button, and when the combination mechanism is set to a correct combination, the spindle can be caused to move from a first spindle position to a second spindle position in a spindle movement direction substantially parallel to the longitudinal axis, and wherein when the combination mechanism is set to the correct combination and the button is moved from the first button position to the second button position, the contact surface is caused to move along with the spindle from the first spindle position to the second spindle position in the spindle movement direction, and the latch is caused to move in a latch movement direction from the first latch position to the second latch position, wherein the latch movement direction is substantially parallel to the spindle movement direction. 
     In an embodiment of the present invention, the combination mechanism further comprises: 
     a plurality of clutches disposed around the spindle, and 
     a plurality of dials engageable with the clutches to control movement of the spindle, the dials having a plurality of indicia to form the correct combination, and wherein the button comprises a button slope positioned in relationship to the contact surface of the spindle and wherein when the button is moved from the first button position to the second button position, the button slope of the button causes the contact surface to move along with the spindle from the first spindle position to the second spindle position in the spindle movement direction. 
     In an embodiment of the present invention, the latch further comprises a latch slope and the button is associated with an extended edge having an edge slope positioned in relationship to the latch slope, and wherein when the button is moved from the first button position to the second button position, the edge slope of the extended edge is arranged to cause the latch slope together with the latch to move in the latch movement direction. 
     In an embodiment of the present invention, the lock further comprises: 
     an overriding key mechanism comprising a cylinder positioned in relationship to the button, the cylinder comprising a first cylinder end and a second cylinder end, wherein the extended edge is fixedly mounted on the second cylinder end, and wherein when the button is moved from the first button position to the second button position, the edge slope of the extended edge and the cylinder is caused to move together with the button. 
     In an embodiment of the present invention, the first cylinder end comprises a key slot dimensioned to receive a key and wherein when the button is in the first button position and the key is inserted into the key slot of the cylinder, the cylinder can be caused to rotate from a first cylinder position to a second cylinder position together with the extended edge in a rotation direction relative to the button, the edge slope is arranged to move the latch slope together with the latch in a latch movement direction from the first latch position to the second latch position. 
     In an embodiment of the present invention, the locking finger further comprises a restriction wall and the cylinder further comprises a key-captive slot dimensioned to receive the restriction wall of the locking finger, and wherein when the cylinder is in the second cylinder position and the locking finger is in the second finger position, the restriction wall of the locking finger is engaged with the key-captive slot, preventing the cylinder from moving from the second cylinder position to the first cylinder position, and when the cylinder is in the second cylinder position, the key is prevented from moving out of the key slot. 
     In an embodiment of the present invention, when the cylinder is in the second cylinder position, the locking finger can be caused to return to the first finger position and the restriction wall of the locking finger is disengaged from the key-captive slot of the cylinder, allowing the cylinder to return to the first cylinder position and the key to be retrieved from the key slot. 
     In an embodiment of the present invention, the lock body further comprises a torque spring positioned in relationship to the locking finger, and when the latch tip is disengaged from the cutout of the locking finger, the torque spring is arranged to urge the locking finger to move from the first finger position to the second finger position. 
     In an embodiment of the present invention, the spindle further comprises a plurality of protrusions and each of the clutches comprises an opening gap associated with the protrusion of a different one of the spindle, and wherein when the dials are set at the correct combination, the opening-gap of each of the clutches is aligned to the associated protrusion of the spindle, allowing the spindle to move from the first spindle position to the second spindle position. 
     In an embodiment of the present invention, the lock body further comprises a spring positioned in relationship to the spindle, and when the button is located in the first button position, the spring is arranged to urge the spindle to remain in the first spindle position. 
     In an embodiment of the present invention, the spindle also has a top edge associated with the contact surface, and the plurality of clutches form a stack of clutches disposed around the spindle, wherein the spring is placed between the top edge of the spindle and the stack of clutches. 
     In an embodiment of the present invention, the lock body further comprises a spring positioned in relationship to the latch, the spring is arranged to urge the latch to move toward the locking finger. 
     In an embodiment of the present invention, wherein each of the clutches is associated with a different one of the dials, each of the clutches comprising a plurality of clutch fins, each of the dials comprising a plurality of teeth arranged to engage with the clutch fins for rotation together relative to the spindle, and wherein when the spindle is in the second spindle position, the clutches can be caused to move relative to the spindle and the dials to a reset position so that the clutch fins become disengaged from the teeth while the protrusions of the spindle are engaged with the opening gaps of the clutches, allowing the dials to rotate relative to the clutches, and wherein the clutch fins comprises one or more longer fins, and the lock body further comprises a plurality of notches arranged to receive the long fins when the clutches are in the reset position, preventing the clutches from rotation relative to the spindle. 
     In an embodiment of the present invention, the lock further comprises 
     a key mechanism comprising a cylinder, the cylinder having a first cylinder end and a second cylinder end, and an extended edge fixedly mounted on the second cylinder end, wherein the first cylinder end comprises a key slot dimensioned to receive a key, and when the key is inserted into the key slot of the cylinder, the cylinder can be caused to rotate from a first cylinder position to a second cylinder position together with the extended edge in a rotation direction relative to the button, and the edge slope is arranged to move the latch slope together with the latch from the first latch position to the second latch position, wherein the locking finger further comprises a restriction wall and the cylinder further comprises a key-captive slot dimensioned to receive the restriction wall of the locking finger, and wherein when the cylinder is in the second cylinder position and the locking finger is in the second finger position, the restriction wall of the locking finger is engaged with the key-captive slot, preventing the cylinder from moving from the second cylinder position to the first cylinder position, and when the cylinder is in the second cylinder position, the key is prevented from moving out of the key slot. 
     In an embodiment of the present invention, the lock comprises a lock body; 
     a hook fixedly disposed on the lock body; 
     a locking finger pivotal mounted on the lock body in relationship to the hook, the locking finger operable in a first finger position when the lock is in the locked mode, and in a second finger position when the lock is in the opened mode; 
     a latch operable in a first latch position and a second latch position, wherein when the latch is in the first latch position, the locking finger is prevented from moving from the first finger position to the second finger position, and when the latch is in the second latch position, the locking finger is allowed to move from the first finger position to the second finger position, wherein the latch comprises a latch tip and the locking finger comprises a cutout dimensioned to receive the latch tip when the latch is in the first latch position, and when the latch is caused to move from the first latch position to the second latch position, the latch tip is disengaged from the cutout, allowing the locking finger to move from the first finger position to the second finger position; a key mechanism comprising a cylinder, the cylinder having a first cylinder end and a second cylinder end, and an extended edge fixedly mounted on the second cylinder end, wherein the first cylinder end comprises a key slot dimensioned to receive a key and when the key is inserted into the key slot of the cylinder, the cylinder can be caused to rotate from a first cylinder position to a second cylinder position together with the extended edge in a rotation direction relative to the lock body, and the edge slope is arranged to move the latch slope together with the latch from the first latch position to the second latch position, wherein the locking finger further comprises a restriction wall and the cylinder further comprises a key-captive slot dimensioned to receive the restriction wall of the locking finger, and wherein when the cylinder is in the second cylinder position and the locking finger is in the second finger position, the restriction wall of the locking finger is engaged with the key-captive slot, preventing the cylinder from moving from the second cylinder position to the first cylinder position, and when the cylinder is in the second cylinder position, the key is prevented from moving out of the key slot. 
     The present invention will become apparent upon reading the description in conjunction with  FIGS. 1A-14B . 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a cross-sectional view of the hook lock according to an embodiment of the present invention taken along line  1 A- 1 A of  FIG. 1B . 
         FIG. 1B  is a cross-sectional view of the hook lock taken along line  1 B- 1 B of  FIG. 1A . 
         FIG. 2  is a perspective view of a lock body half forming part of the hook lock. 
         FIG. 3  is a perspective view of another lock body half forming part of the hook lock. 
         FIGS. 4A and 4B  are opposite perspective views of a locking finger. 
         FIG. 5  is a perspective view of a button forming part of the hook lock. 
         FIGS. 6A and 6B  are perspective views of a cylinder forming part of the hook lock. 
         FIG. 7  is a perspective view of a spindle forming part of the hook lock. 
         FIGS. 8A and 8B  are perspective views of a clutch forming part of the hook lock. 
         FIG. 9  is a perspective view of a dial forming part of the hook lock. 
         FIGS. 10A and 10B  are perspective views of a reset-button-with-clutch forming part of the hook lock. 
         FIG. 11  is a perspective view of a latch forming part of the hook lock. 
         FIG. 12A  is a cross-sectional view of a hook lock taken along line  12 A- 12 A of  FIG. 12B . 
         FIG. 12B  is a cross-sectional view of a hook lock taken along line  12 B- 12 B of  FIG. 12A . 
         FIG. 13A  is a cross-sectional view of a hook lock taken along line  13 A- 13 A of  FIG. 13B . 
         FIG. 13B  is a cross-sectional view of a hook lock taken along line  13 B- 13 B of  FIG. 13A . 
         FIG. 14A  is a cross-sectional view of a hook lock taken along line  14 A- 14 A of  FIG. 14B . 
         FIG. 14B  is a cross-sectional view of a hook lock taken along line  14 B- 14 B of  FIG. 14A . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The numbering of the lock and its components is as follows: 
     Padlock.  20  Lock Body.  20   a  Tail-receiving slot.  21  Hook.  22  cylinder-receiving hole.  23  Pivot-pole.  24  torque-spring slot.  25  Stopping edge.  26  Latch path.  27  Cut Edge.  28  Notch.  29  Spindle wall.  30  Lock Body other half.  30   a  Tail-receiving slot.  31  cylinder-receiving hole.  32  Pole-receiving hole.  33  Stopping edge.  34  Body Wall.  35  Cut Edge.  36  Latch path.  37  Notch.  40  Locking Finger.  41  Locking Tip.  42  Restriction wall.  43  torque-spring wall.  44  pole-receiving hole.  45  Cutout.  46  Locking-finger Tail.  50  Button.  51  Button edge.  52  Button Wall.  53  Button Slope.  54  Rotational-control slot.  55  Wafer Slot.  60  Cylinder.  61  Control Edge.  62  Edge Slope.  63 . Extended edge.  64  Key-Captive Slot.  68  Key slot.  70  Spindle.  71  Contact surface.  72  Top Edge.  73  Protrusion.  78 . Longitudinal Axis.  80  Clutch.  81 . Short Fin.  82  Long Fin.  83  Opening Gap.  84  Clutch Opening.  85  Faulty gates.  90  Dial.  91  Teeth.  100  Reset-Button Clutch.  101  Short Fin.  102  Long Fin.  103  Opening Gap.  104  Button knob.  105  Clutch Opening.  106  Faulty gates.  110  Torque Spring.  120  Spindle Spring.  130  Separation Ring.  140  Key.  150  Latch.  151  Latch Tip.  152  Latch Slope.  153  Latch Surface.  154  Spring hole.  160  Latch Spring. 
     Components that are mentioned in the specification but not numbered: Wafers and wafer springs in the cylinder and the ratchet spring plate associated with the dials. 
     Locked Mode (FIG.  1 A- 11 ) 
     A padlock  10 , according to an embodiment of the present invention, has a lock body  20  ( 20 / 30 ) with a built-in hook  21  as a member to hook up an object to be locked. A locking finger  40  is engaged with the hook  21  when the lock  10  is operated in the locked mode and is disengaged with the hook  21  when the lock  10  is operated in the opened mode. The locking finger  40  has a locking tip  41  arranged to contact the tip of the hook  21  when the locking finger  40  is engaged with the hook  21 . The movement of locking finger  40  is facilitated by a torque spring  110  which is hinged on a torque-spring slot  24  of lock body  20  and a torque-spring wall  43  of locking finger  40 . As illustrated in  FIG. 1A , the torque spring  10  is obscured by the locking finger  40 . When the lock  10  is in the opened mode, a user must manually move the locking finger  40  back to its engaging position with the hook  21 . The user may push the locking-finger tail  46  of the locking finger  40  back into a tail-receiving slot  20   a / 30   a  of lock body  20 / 30  so as to engage the locking tip  41  with the hook  21 . The locking finger  40  is pivotally mounted on lock body  20 . The locking finger  40  has a pole-receiving hole  44  which is located between a pivot pole  23  and a pole-receiving hole  32  of lock body  20 / 30 . The locking finger  40  also has a torque-spring wall  43  for mounting the torque spring  110 . One end of torque spring  110  is placed in a torque-spring slot  24  of lock body  20 , and the other end of torque spring  110  is placed in the torque-spring wall  43  of locking finger  40 . The lock body  20 / 30  has a stopping edge  25 / 33 , and the locking finger  40  has a restriction wall  42  arranged to contact the stopping edge  25 / 33  once the locking finger  40  is moved back to its engaging position from the disengaging position. The restriction wall  42  and the stopping edge  25 / 33  prevent the locking finger  40  from pivoting further from the engaging position to ensure that the locking tip  41  stays in a locked position with the hook  21 . 
     The Overriding Key Mechanism 
     The overriding key mechanism has a cylinder  60  partially assembled inside a button  50 . The body  20 / 30  has a cylinder-receiving hole  22 / 31  dimensioned to receive the cylinder  60 . As the button  50  is arranged as a cylinder housing, the button  50  is also installed in part of the cylinder-receiving hole  22 / 31 . The cylinder  60  has a control edge  61 . The button  50  has a rotation-control slot  54  dimensioned to receive the control edge  61  of cylinder  60 . In the locked mode, wafers (not shown) in the cylinder  60  are pushed outward by wafer springs (not shown) into the wafer slots  55 , preventing the cylinder  60  from a rotational movement. The button  50  has a button wall  52  arranged to contact a cut edge  27 / 35  of lock body  20 / 30 . The button wall  52  prevents the button  50  from having a rotational movement relative to lock body  20 . The button wall  52  also limits the button  50  from traveling beyond the cut-edge  27 / 35  so as to prevent the button  50  from falling out of the cylinder-receiving hole  22 / 31 . 
     The lock  10  has a latch  150  to control the pivotal movement of the locking finger  40 . The latch  150  has a latch slope  152  and a latch surface  153 . The cylinder  60  has an edge slope  62  and an extended edge  63  positioned in relationship to the latch slope  152  and the latch surface  153 . When the lock  10  is operated in the locked mode, the cylinder  60  does not have a rotational or linear movement, and the edge slope  62  and the extended edge  63  remain stationary. 
     The latch  150  has a latch tip  151 . The locking finger  40  has a cutout  45  dimensioned to receive the latch tip  151  when the lock  10  is operated in the locked mode. As the cylinder  60  and the button  50  have no movement, the latch tip  151  of latch  150  remains engaged with the cutout  45  of locking finger  40  so that the locking finger  40  remains engaged with the hook  20 . 
     The button  50  is also used to cause the spindle  70  to move downward in a spindle movement direction substantially parallel to the longitudinal axis  78  of spindle  70 . The button  50  has a button slope  53 , and the spindle  70  has a contact surface  71  positioned in relationship to the button slope  53 . As described below in reference to the combination mechanism, the spindle  70  is movable in a spindle movement direction only when the user sets a correct combination on the combination mechanism. Otherwise, the spindle  70  has no motion relative to lock body  20  and the button  50  is prevented from being pushed inward. Only when the spindle  70  is movable, can the button  50  be pushed inward in a button movement direction from a first button position to a second button position. Through the contact between the button slope  53  and the contact surface  71  of spindle  70 , the inward movement of the button  50  causes the contact surface  71  together with the spindle  70  to move from the first spindle position to the second spindle position in the spindle movement direction. The button movement direction is substantially perpendicular to the spindle movement direction. 
     When the button  50  is prevented from inward movement, the tip  151  of the latch  150  remains stationary. Furthermore, since the cylinder  60  has no rotational movement, the extended edge  63  of cylinder  60  does not exert a force upon the latch surface  153  of latch  150 . As such, the latch tip  151  of latch  150  remains engaged with the cutout  45  of locking finger  40 . The latch  150  is positioned in the latch path  26 / 36  of lock body  20 / 30 . A latch spring  160  is placed in the spring-hole  154  of latch  150  to push the latch  150  toward the locking finger  40  to ensure the lock  10  remains in the locked position. 
     The Combination Mechanism 
     The combination mechanism comprises a plurality of clutches  80 , including a rest-button clutch  100 , movably disposed around the spindle  70 , and a plurality of dials  90  engageable with the clutches  80 / 100  to control the rotation of the clutches. Each of the clutches  80 / 100  has one or more short fins  81 / 101  and one or more long fins  82 / 102  on the clutch&#39;s outer face, and an opening gap  83 / 103  made through the clutch&#39;s inner ring. The opening  84  of the inner ring on the clutches  80 / 100  allows the spindle  70  to pass through. Each of the dials  90  has a plurality of teeth  91 . Each of the dials  90  is associated with a different one of the clutches  80 / 100 . When lock  10  is in the locked mode, teeth  91  of dials  90  are arranged to engage with short fins  81 / 101  and long fins  82 / 102  of clutches  80 / 100 . The rotation of each of dials  90  causes the rotation of the associated clutch  80 / 100  in the same manner. The spindle  70  has a plurality of protrusions  73 , each of which is associated with one of the clutches  80 / 100 . The spindle  70  also has a top edge  72  associated with the contact surface  71 . 
     In the locked mode, the opening gap  83 / 103  of at least one of the clutches  80 / 100  is not aligned with the associated protrusion  73  of spindle  70 . This misalignment prevents the spindle from moving downward. The top edge  72  of spindle  70  has a dual function. The first function is to prevent the spindle  70  from moving further upward when the lock  10  is in the locked mode as the top edge  72  is in contact with a spindle wall  29  of lock body  20 . A spindle spring  120  is arranged to push a separation ring  130  together with the stack of clutches  80 / 100  away from the top edge  72  of spindle  70 . As such, the relationship between the clutches  80 / 100  and the spindle  70  can be maintained. The second function of the top edge  72  is to prevent any rotational movement of the spindle  70  relative to lock body  20 . Each of the clutches  80  has a set of faulty gates  85  on top and bottom of its inner ring. The reset-button clutch  100  has a set of faulty gates  106  on its upper side. When the lock  10  is in the locked mode, an unauthorized user may try to push the button  50  inward while rotating the dials  90  along with the clutches  80 / 100  in an attempt to align the opening gaps  83 / 103  with the protrusions  73  of spindle  70 . Pushing the button  50  inward may force the spindle  70  slightly downward, causing the protrusions  73  of spindle  70  to become jammed into the faulty gates  85 / 106 . As such, the dials  90  cannot be further rotated in order to align the opening gaps  83 / 103  of clutches  80 / 100  with the protrusions  73  of spindle  70 . 
     In an embodiment of the present invention, both the combination mechanism and the overriding key mechanism are configured to control the movement of the latch  150  directly. When the latch tip  41  is disengaged from the cutout  45  of locking finger  40 , the movement of the locking finger  40  to disengage from the hook  21  is caused by the spring action provided by the torque spring  110 . However, the engagement of the locking finger  40  with the hook  21  from the disengaging position is manually carried out by the person who uses the combination mechanism or the key overriding mechanism. 
     Unlock by Combination (FIG.  12 A- 12 B) 
     When the lock  10  is in the locked mode, the teeth  91  of dials  90  are engaged with the short-fins  81 / 101  and the long fins  82 / 102  of clutches  80 / 100 . As the dials  90  are rotated to form the correct combination (the lock-open code), the opening gaps  83 / 103  of the clutches  80 / 100  are aligned with the protrusions  73  of spindle  70 . As such, the user can push the button  50  together with the cylinder  60  inward so that the contact between the button slope  53  and the contact surface  71  of the spindle  70  causes the spindle  70  to move downward, allowing the button  50  to move further inward together with the cylinder  60 , causing the edge slope  62  to push the latch slope  152  together with the latch  150  downward. When the button  50  is moved from the first button position to the second position, the latch  150  is caused to move from the first latch position to the second latch position where the latch tip  151  is disengaged from the cutout  45  of locking finger  40 . The locking finger  40 , under the urging force of the torque spring  110 , moves from the first locking position to the second locking position, causing the locking tip  41  of locking finger  40  to disengage from the hook  21  of lock body  20 , thereby changing the lock  10  from the locked mode to the opened mode. 
     To change the lock  10  from the opened mode back to the locked mode, the user must move the locking finger  40  to engage it with the hook  21 . Under the spring action of latch spring  160 , the latch  150  is pushed upward toward the locking finger  40  to engage the latch tip  151  with the cutout  54  of locking finger  40 . As the latch  150  moves upward, the edge slope  62 , along with cylinder  60  and button  50 , is pushed outward by the latch slope  152 . As the button  50  is pushed from the second button position to the first button position, the button slope  53  is moving away from the contact surface  71  of spindle  70 , allowing the spindle spring  120  to push the spindle  70  upward from the second spindle position to the first spindle position. The user can now rotate the dials  90  together with the clutches  80 / 100  so that one or more of the opening gaps  83 / 103  become misaligned with the protrusions  73  of spindle  70 . 
     Unlock by Key (FIG.  13 A- 13 B) 
     When a correct key (cut key)  140  is inserted into the key slot  68  of cylinder  60 , the wafers in cylinder  60  are caused to move away from the wafer slots  55  of button  50 , and the cylinder  60  can rotate. As the cylinder  60  rotates, the extended edge  63  of cylinder  60  also rotates and contacts the latch surface  153  of latch  150 . As the extended edge  63  rotates further, the latch surface  153  together with the latch  150  is caused to travel further downward. When the latch  150  moves from the first latch position to the second latch position, the latch tip  151  becomes disengaged from the cutout  45  of locking finger  40 . Under the spring action of the torque spring  110 , the locking finger  40  moves away from the hook  21  to change the lock  10  to the opened mode. The key user must leave the key  140  in the cylinder  60  as the restriction wall  42  of the locking finger  40  is engaged with the key-captive slot  64  of cylinder  60 . The engagement between the restriction wall  42  and the key-captive slot  64  prevents the cylinder  60  from rotation backward. 
     In the relocking process, the key-user must first push the locking-finger tail  46  back to the tail-receiving slot  20   a / 30   a  of lock body  20 / 30  to engage the locking finger  40  with the hook  21 . By doing so, the restriction wall  42  becomes disengaged from the key-captive slot  64  of cylinder  60 . Then the key-user can rotate the cylinder  60  and retrieve key  140  from cylinder  60 . When the locking finger  40  is moved back to the locked position, the latch tip  151  and the cutout  45  of locking finger  40  are aligned. The latch  150  is pushed toward the locking finger  40  by the latch spring  160  to cause the latch tip  151  to engage with the cutout  45  of locking finger  40  to the locking position. The advantage of this arrangement is that the key user will lock the padlock before withdrawing the key from the cylinder. 
     Reset Mode (FIG.  14 A- 14 B) 
     When the lock  10  is opened using the lock open combination mode, the user can push the reset-button clutch  100  inward to cause short fins  81 / 101  and long fins  82 / 102  of clutches  80 / 100  to disengage from the teeth  91  of dials  90 . The long fins  82 / 102  become engaged with the notches  28  of lock body  20  to prevent the clutches  80 / 100  from rotation during the entire reset process. Each of the protrusions  73  of the spindle  70  is also engaged with the opening gap  83 / 103  of the associated clutch  80 / 100 . The user can rotate one or more dials  90  to set a new combination code. After setting the new code, the user can release the reset-button clutch  100  to allow the spindle spring  120  to push the separation ring  130  together with the stack of clutches  80 / 100  back to the original position. As such, the short fins  81 / 101  and long fins  82 / 102  of clutches  80 / 100  become engaged with the teeth  91  of dials  90 . The separation ring  130  is used to separate the top clutch  80  from the spindle spring  120 . 
     In summary, the present invention is directed to a hook lock  10  which is operable in a locked mode as shown in  FIG. 1A , and in an opened mode as shown in  FIG. 12A  and  FIG. 13A . As illustrated in  FIG. 1A , the lock  10  has a lock body  20  having a first or upper body portion and a second or lower body portion; a hook  21  located in the first body portion; a locking finger  40  pivotally mounted in the first body portion in relationship to the hook  21 . The lock  10  has a latch  150  engageable with the locking finger  40 . The lock can be opened by a combination mechanism as shown in  FIG. 12A  or by an overriding mechanism as shown in  FIG. 13A . When the lock  10  is in the locked mode, the locking finger  40  is in a first finger position to engage with the hook  21  and the latch  140  is in a first latch position (up) to engage with the locking finger  40 . When the lock  10  is in the opened mode, the latch  150  is in a second latch position (down) and disengaged from the locking finger  40 , and the locking finger  40  is in a second finger position and disengaged from the hook  21 . 
     The combination mechanism has a plurality of clutches  80  forming a stack of clutches around a spindle  70 , and a plurality of dials  90  engageable with the clutches  80 . Each of the dials  90  has a plurality of indicia for forming a combination code. When the dials  90  are set to a correct combination, the spindle  70  can be pushed downward from a first spindle position (up) to a second or lower spindle position (down) in a spindle movement direction substantially parallel to the longitudinal axis  78  of spindle  70  by a button  50  which can be pushed inward from a first button position to a second button position. When the button  50  moves to the second button position, it also causes the latch  150  to move downward from the first latch position to the second latch position to open the lock. 
     The overriding key mechanism has a cylinder  60  having a key slot  68  on the first cylinder end (outside) to receive a key. When the key is inserted into the cylinder  60 , the cylinder  60  can be rotated to cause the latch  150  to move from the first latch position to the second latch position to open the lock. 
     The latch  150  has a latch tip  151  and the locking finger  40  has a cutout  45  dimensioned to receive the latch tip  151  when the latch is in the first latch position (see  FIG. 1A ), and when the latch is caused to move downward from the first latch position to the second latch position (see  FIGS. 12A and 13A ), the latch tip  151  is disengaged from the cutout  45 , allowing the locking finger  40  to move from the first finger position to the second finger position. 
     The spindle  70  has a first spindle end (upper) and a second spindle end (lower). The first spindle end has a contact surface  71 . The button  50  has a button slope  53  positioned in relationship to the contact surface  71  of spindle  70 . When the combination mechanism is set to a correct combination and the button  50  is pushed inward from the first button position to the second button position, the contact surface  71  is caused to move downward along with the spindle  70 . The latch  150  has a latch slope  152 . The button  50  is associated with an extended edge  63  having an edge slope  62  positioned in relationship to the latch slope  152 . When the button  50  is pushed to the second button position, the edge slope  62  of the extended edge  63  causes the latch slope  152  together with the latch  150  to move downward in a direction substantially parallel to the spindle movement direction. As shown in  FIG. 6A , the extended edge  63  is fixedly mounted on the second cylinder end. 
     In an embodiment of the present invention, the locking finger  40  also has a restriction wall  42  and the cylinder  60  also has a key-captive slot  64  dimensioned to receive the restriction wall  42  of locking finger  40 . When the cylinder  60  is in the second cylinder position and the locking finger  40  is in the second finger position (see  FIGS. 13A, 13B ), the restriction wall  42  of locking finger  40  is engaged with the key-captive slot  64 , preventing the cylinder  60  from rotating backward from the second cylinder position to the first cylinder position. When the cylinder  60  is in the second cylinder position, the key is prevented from moving out of the key slot, and the locking finger  40  can be caused to return to the first finger position so that the restriction wall  42  of the locking finger  40  is disengaged from the key-captive slot  64  of cylinder  60 , allowing the cylinder  60  to return to the first cylinder position and the key to be retrieved from the key slot. 
     In an embodiment of the present invention, the lock body  20  has a torque spring  110  positioned in relationship to the locking finger  40 . When the latch tip  151  is disengaged from the cutout  45  of locking finger  40 , the torque spring is arranged to urge the locking finger  40  to move from the first finger position to the second finger position. As shown in  FIG. 7 , the spindle  70  has a plurality of protrusions  73 . As shown in  FIG. 8B , each of the clutches  80  has an opening gap  83  associated with the protrusion of a different one of the spindle. When the dials are set to the correct combination, the opening-gap  83  of each of the clutches  80  is aligned to the associated protrusion  73  of spindle  70 , allowing the spindle to move downward from the first spindle position to the second spindle position. 
     As shown in  FIG. 1B , the lock body also has a spring  120  positioned in relationship to the spindle  170 . When the button  50  is located in the first button position, the spring  120  is arranged to urge the spindle  70  to remain in the first spindle position (up). 
     As shown in  FIG. 7 , the spindle  70  also has a top edge  72  associated with the contact surface  71 . As shown in  FIG. 1B , the spring  120  is placed between the top edge  72  of spindle  70  and the stack of clutches  80 . 
     As shown in  FIG. 1A , the lock body also has a spring  160  positioned in relationship to the latch  150 , and the spring  160  is arranged to urge the latch  150  to move toward the locking finger  40 . 
     In an embodiment of the present invention, each of the clutches  80  is associated with a different one of the dials  90 . Each of the clutches  80  has a plurality of clutch fins  81 / 82 , and each of the dials  90  has a plurality of teeth  91  arranged to engage with the clutch fins  81 / 82  for rotation together relative to the spindle  70 . When the spindle  70  is in the second spindle position (down), the clutches  80  can be caused to move upward relative to the spindle  70  and the dials  90  to a reset position. At the reset position, the clutch fins  81 / 82  become disengaged from the teeth  91  of dials  90  while the protrusions  73  of spindle  70  are engaged with the opening gaps  83  of the clutches, allowing the dials  90  to rotate relative to the clutches  90  to set a new combination code. 
     As shown in  FIG. 2 , the lock body  20  has a plurality of notches  28  arranged to receive the long fins  82  of clutches  80  when the clutches  80  are in the reset position, preventing the clutches  80  from rotation relative to the spindle  70 . 
     Thus, although the invention has been described and illustrated with respect to exemplary embodiments thereof, the foregoing and various other additions and omissions may be made therein and thereto without departing from the scope of the present invention.