Patent Publication Number: US-7712799-B2

Title: Hidden lock locked to an inner side of a doorplate

Description:
FIELD OF THE INVENTION 
   The present invention relates to door locks, and particular to a hidden door lock locked to an inner side of a doorplate having a top seat assembly with a resisting unit. A bent stop is extended from the resisting unit. When a top rod reduces inwards, the stop will resist against a neck of the top rod to prevent a lower head to contact the ground. A pin device is installed for retaining the lock in high temperature. 
   BACKGROUND OF THE INVENTION 
   For preventing fire accident in high building, fireproof doors are widely installed between different floors. Generally, the locks of the fireproof doors are installed in the doorframes and have very complicated structures so that the manufacturing processes are tedious. Furthermore, the lock is difficult in operation and is easy to have faults. Especially, when the fireproof door is opened, a lower protruded head will protrude upwards due to a compression of a spring so that it will contact the groove with the movement of the door. Not only the ground is worn and the door will be destroyed. Furthermore, generally, the fireproof door is closed, when fire accident occurs. 
   In general design, in high temperature, the buckling studs will not reduce inwards and then the fireproof doors will not open automatically so as to prevent the expansion of fire. This is the main function of the fireproof door. 
   SUMMARY OF THE INVENTION 
   Accordingly, the primary object of the present invention is to provide a hidden door lock locked to an inner side of a doorplate having a top seat assembly with a resisting unit. A bent stop is extended from the resisting unit. When a top rod reduces inwards, the stop will resist against a neck of the top rod to prevent a lower head to contact the ground. A pin device is installed for retaining the lock in high temperature. 
   To achieve above objects, the present invention provides a hidden lock locked to an inner side of a doorplate; the lock having a lock body which has a swingable crank; a cover covering upon the lock body; a horizontal pressable handle having one end extending to the lock body so as to contact one end of the crank; a retainer and an assembly cover covering upon the end of the handle; the lock comprising: a top seat assembly; a top rod; the top seat assembly being assembled to the top rod; a linking rod installed to a lower side of the top rod by using a pin to pass the top rod and the linking rod; a lower end of the linking rod having thread; a lower rod having a thread at an upper side thereof and a lower end of the lower rod having a hole; the thread of the lower rod being engaged into the lower engaging tube; a lower head having a receiving space for receiving a lower end of the lower rod; a spring being placed in the receiving space of the lower head and below a lower bottom of the lower rod; two opposite lateral sides of the lower head having a respective slot; a pin passing through the slot to be inserted into the hole; the pin of the lower head being slideable along the slots of the lower head; a top seat assembly including an upper supporting sheet and a lower supporting sheet; each of the upper supporting sheet and the lower supporting sheet having an opening; the top rod passing through the openings of the upper supporting sheet and lower supporting sheet; the opening of the upper supporting sheet having a protrusion at an upper side thereof; a resisting unit installed in the receiving groove; an upper end of the resisting unit being retained to the upper supporting sheet by using a retaining bar to pass through the upper end of the resisting unit to an upper side of the upper supporting sheet; one lower end of the resisting unit being combined to upper supporting sheet by using a post to pass through holes of the upper supporting sheet and resisting unit; a front side of the resisting unit being extended with a bent stop; an elastic unit being installed at two lower legs of the resisting unit; the post passing through the elastic unit to fix the elastic unit to the lower supporting sheet; the lower supporting sheet being formed with a recess; two opposite sides of walls of the recess having holes; an inner side of each hole of the recess having a retaining stud; a small part of the stud being installed in the hole of the recess; and a large part of the stud resisting against an inner side of the hole of the recess; a protrusion of the pin being inserted into a hole in the stud; a press unit having a U shape end; the pin passing through the U shape end to be retained therein; an O ring enclosing the pin and is at an inner side of the press unit; one end of the press unit having a round hole; a screw serving to fix the press unit to the lower supporting sheet; wherein when the press unit is pressed downwards in fire accident and in high temperature, the O ring will melt and the pin will pass through the retaining stud to insert into the through hole of the top rod to fix the lock so as to prevent the fire from expansion; and the connecting shaft having a groove, plurality of slots, a plurality of holes, an upper engaging tube and a lower engaging tube. 
   The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an explosive schematic view of the present invention. 
       FIG. 2  is an assembled schematic view of the present invention. 
       FIG. 3  is an explosive schematic view of the present invention. 
       FIG. 4  is an assembled schematic view of the present invention. 
       FIG. 5  shows the operation of the door lock of the present invention. 
       FIG. 6  shows the opening of the door through the top seat structure of the present invention. 
       FIG. 7  is an explosive schematic view of the connecting shaft according to the present invention. 
       FIG. 8  shows an assembled schematic view of the connecting shaft according to the present invention. 
       FIG. 9  is a schematic view about a preferred embodiment of the present invention. 
       FIG. 10  is an explosive schematic view about the preferred embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In order that those skilled in the art can further understand the present invention, a description will be provided in the following in details. However, these descriptions and the appended drawings are only used to cause those skilled in the art to understand the objects, features, and characteristics of the present invention, but not to be used to confine the scope and spirit of the present invention defined in the appended claims. 
   Referring to  FIGS. 1 ,  2 ,  9  and  10 , the structure of the present invention is illustrated. 
   The lock  10  of the present invention is locked to an inner side of a doorplate. The lock has the following elements. 
   A lock body  8  has a swingable crank  81 . A cover  82  covers upon the lock body  8 . 
   A horizontal pressable handle  9  has one end extending to the lock body  8  so as to contact one end of the crank  81 . A retainer  91  and an assembly cover  92  covers upon the end of the handle  9 . 
   The structure of the lock body  8  and handle  9  are known in the prior art. 
   The lock  10  has a top seat assembly  2  which is assembled with a top rod  3 . 
   A linking rod  4  is installed to a lower side of the top rod  3  by using a pin to pass the top rod  3  and the linking rod  4 . A lower end of the linking rod  4  has thread  41 . 
   A lower rod  5  has a thread  51  at an upper side thereof and a lower end of the lower rod  5  has a hole  52 . The thread  51  of the lower rod  5  is engaged into the lower engaging tube  13 . 
   A lower head  6  has a receiving space  62  receiving a lower end of the lower rod  5 . A spring  62  is placed in the receiving space  62  of the lower head  6  and below a lower bottom of the lower rod  5 . Two opposite lateral sides of the lower head  6  have respective slots  63 . A pin  64  passes through the slot  63  to be inserted into the hole  52 . The pin  64  of the lower head  6  is slideable along the slots  63  of the lower head  6 . 
   Referring to  FIGS. 1 ,  3  and  5 , the elements related to the present invention will be further described herein. 
   A top seat assembly  2  includes an upper supporting sheet  21  and a lower supporting sheet  22 . Each of the upper supporting sheet  21  and the lower supporting sheet  22  has an opening  210 . The top rod  3  passes through the openings  210  of the upper supporting sheet  21  and lower supporting sheet  22 . 
   The opening  210  of the upper supporting sheet  21  has a protrusion  211  at an upper side thereof. 
   A resisting unit  25  is installed in the receiving groove  27 . An upper end of the resisting unit  25  is retained to the upper supporting sheet  21  by using a retaining bar  254  to pass through the upper end of the resisting unit  25  to an upper side of the upper supporting sheet  21 . 
   One lower end of the resisting unit  25  is combined to upper supporting sheet  21  by using a post  251  to pass through holes of the upper supporting sheet  21  and the resisting unit  25 . A front side of the resisting unit  25  is extended with a bent stop  253 . An elastic unit  252  is installed at two lower legs of the resisting unit  25 . The post  251  passes through the elastic unit  252  so fix the elastic unit  252  to the lower supporting sheet  22 . 
   The lower supporting sheet  22  is formed with a recess  24 . Two opposite sides of walls of the recess  24  have holes  240 . An inner side of each hole  240  of the recess  24  has a retaining stud  263 . A small part of the stud  263  is installed in the hole  240  of the recess  24  and a large part of the stud  263  resists against an inner side of the hole  240  of the recess  24 . A protrusion  2610  of the pin  261  is inserted into a hole in the stud  263 . A press unit  262  has a U shape end  2621 . The pin  261  passes through the U shape end  2621  to be retained therein. An O ring  264  encloses the pin  261  and is at an inner side of the press unit  262 . One end of the press unit  262  has a round hole  2622 . A screw  265  serves to fix the press unit  262  to the lower supporting sheet  22 . 
   Referring to  FIGS. 2 ,  5  and  6 , the structure of the top rod  3  of the present invention is illustrated. The top rod  3  has a slot  31 , a neck  32  below the slot  31  and a plurality of through holes  33 . The slot  31  is corresponding to the protrusion  211  of the upper supporting sheet  21 . In assembly (see  FIG. 2 ), the top rod  3  passes through the opening  210  of the upper supporting sheet  21 . The protrusion  211  resists against the top rod  3  to prevent the top rod  3  from loosing so that the top rod  3  is adjustable to make the neck  32  of the top rod  3  being at a predetermined position with respect to the bent stop  253  of the resisting unit  25  so that the assembly work can be positioned easily. 
   When the press unit  262  is pressed downwards in fire accident and thus in high temperature, the O ring  264  will melt and the pin  261  will pass through the retaining stud  253  to insert into the through hole  33  of the top rod  3  to fix the lock so as to prevent the fire from expansion. 
   Referring to  FIGS. 7 and 8 , the exploded view of the connecting shaft  1  of the present invention is illustrated. The connecting shaft  1  has a groove  11 , a plurality of slots  14 , a plurality of holes  34 , an upper engaging tube  12  and a lower engaging tube  13 . A plurality of rivets  16  passes through the slots  14  and the holes  34  to retain the upper engaging tube  12  and lower engaging tube  13  in the groove  11 . Each rivet  16  passes through two opposite sides of the groove  11  so that the upper engaging tube  12  and lower engaging tube  13  are rotatable in the groove  11 . Two interconnect units  17  are installed to a rivet  16  which retain the upper engaging tube  12 . Two linking units  18  are connected to the rivet  16  retaining the lower engaging tube  13 . Each pair of the interconnect unit  17  and the linking unit  18  are pivoted to two ends of a transfer sheet  19 . A central area of the transfer sheet  19  has a hole  190  for receiving a rivet  16 . A buckle  191  is retained between the two transfer sheets  19 . The swingable crank  81  is in contact with the hook  191  of the interconnect shaft  19 . The crank  81  will drive the hook  191  to move. A pin passes through the two interconnect unit  17  and two transfer sheets  19  so as to retain the two pairs of the interconnect units  17  and the two transfer sheets  19 . An elastic element  20  is connected between two rivets  16 . 
   A top side of the lower engaging tube  13  has an expanding sheet  122  for retaining the lower engaging tube  13  in the groove  11 . An upper side of the upper engaging tube  12  has an expanding sheet  121 . 
   In assembly the upper engaging tube  12  is engaged to the thread  41  at a lower end of the linking rod  4 . The upper engaging tube  12  and lower engaging tube  13  are slidable along the slots  14 . The crank  81  is buckled to the hook  191  so that the crank  81  can drive the buckle  191  to move to separate an end of the top rod  3 . The end portion of the top rod  3  is pulled away and the lower head  6  is reduced back to separate from a latch. A lateral side of the connecting shaft  1  is installed with at least one insertion device  26 . In fire accident, in high temperature, the O ring  264  will melt. The pin  261  will pass through the connecting shaft  1  to insert into the hole  35  of the transfer unit  18  to fix the lock and prevent air from expansion. 
   When the top rod  3  reduces inwards, the elastic element  20  will be compressed. The resisting unit  25  will move toward an inner side of the groove  23  due to the elastic force of the elastic unit  252  so that the stop  253  resists against the neck  32  of the top rod  3  to fix the top rod  3  and the lower rod  5  so as to prevent the head  6  from contacting the ground. When the door is closed, the retaining bar  254  resists against a doorframe so that the stop  253  separates from the neck  32  of the top rod  3 . The elastic element  20  of the connecting shaft  1  will release the elastic force to make the end portion of the top rod  3  to insert into the head  6  so as to be inserted into the latch to be fixed therein. 
   The present invention is thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.