Abstract:
The present invention provides a door handle apparatus consisting of a handle, a lock housing, a transmission mechanism, and a locking mechanism. The handle is pivotally engaged with the lock housing. The locking mechanism is engaged with one end of the lock housing and the handle. When the handle is rotated, the locking mechanism makes relative sliding and movement about the handle. The transmission mechanism is engaged with the other end of the lock housing and moves relative to the locking mechanism. The locking mechanism has a burglar free locking piece that prevents the door handle apparatus from being disassembled without being unlocked by a key first. After the door handle is engaged with the transmission mechanism, the door handle is still rotatable and movable via the lock housing.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to door handle apparatuses, and more particularly, to a door handle apparatus that remains rotatable when in a locked state. 
         [0003]    2. Description of the Prior Art 
         [0004]    When in a locked state, a conventional door handle is not rotatable as it is fastened. However, when subjecting to an external force or the weight of a heavy object, the door handle is rotated to an extent that its internal parts are damaged. Therefore, a door handle structure that is rotatable when in a locked state has been developed to overcome the drawbacks described above. 
         [0005]    Referring to  FIGS. 1A ,  1 B and  1 C,  FIGS. 1A ,  1 B and  1 C are an exploded diagram and two enlarged views illustrating the structures of a conventional door handle, respectively. The door handle apparatus consists of a handle  2 , a connection base  4 , a fixing base  11 , a rotation base  13 , a transmission base  16  and a rotation rack  26 . One end of the handle  2  is engaged with the connection base  4 , and is fastened by a fastener  5  to transmit force. At the same time, the handle  2  may be engaged with a positioning ring  9 , a ring  10  and the fixing base  11  in a sequential order. The connection base  4  is hollow, which allows accommodation of a partition panel  8 , the rotation base  13 , the transmission base  16 , and a spring  23 . After the aforesaid parts are added in the connection base  4 , the connection base  4  is pressed with a sleeve cylinder  24 . A recess  22 , which is formed inside the rotation base  13 , allows a rotation piece  3  disposed in the door handle  2  to be inserted therein to transmit force. The rotation rack  26  is fastened with one side of the sleeve cylinder  24  by a positioning cylinder  27 . The elasticity of the spring  23  causes the handle  2  and the connection base  4  to rotate idly when the handle  2  is rotated, disabling the rotation rack  26  to rotate to transmit force to one side of a door lock of an escape door, thus damages to the door handle caused by external forces applied thereupon in a lockedstate are prevented. 
         [0006]    Moreover, a torque spring  28  is engaged with one side of the positioning cylinder  27 , and a fixing piece  29  is then pressed on the positioning cylinder  27 . A sheath  30  is engaged with one side of the fixing base  11  and covered by a cover plate  32 . Then, the protective sheath  30  is fixed to a plurality of lock bolts  12  by screwing into the fixing base  11  with a plurality of screws  41 . The cover plate  32  is formed with a screw hole  31  for screwing into to one side of the door lock of an escape door, such that the inner parts of the door lock can be protected from damages. 
         [0007]    Furthermore, after the rotation rack  26  is connected with the door lock of an escape door, when a key  1  rotates to a specific angel, the rotation piece  3  transmits force to rotate the rotation base  13 . Push action caused by friction occurs between a V-shaped cutting groove  14  of the rotation base  13  and a V-shaped bump  20  of the transmission base  16 . A pair of protruding ears  17 ,  19  formed on both sides of the transmission base  16  are disposed in a pair of guiding slots  6 ,  7  formed on the connection base  4 , respectively. This allows the transmission base  16  to move horizontally toward one side, until a top end  21  of the V-shaped bump  20  is fastened to a pair of slots  130 ,  131  formed in the rotation base  13 . Simultaneously, the spring  23 , which is compressed to one side of the connection base  16 , enables a groove  18  formed in the transmission base  16  and a threshold block  25  of the rotation rack  26  to be engaged to transmit force, thereby allowing the transmission base  16  and the rotation rack  25  to rotate by the force transmitted through the connection base  4 . 
         [0008]    However, conventional door handle apparatuses use an elastic spring to transmit force for connecting or disconnecting a locking structure and a rotating structure. After a long period of use of the apparatuses, problems like elastic fatigue occurs on the spring, affecting the transmission relationship among the parts and may eventually cause malfunction. 
         [0009]    Accordingly, it is important to develop a door handle apparatus that can remedy the drawbacks of prior arts and offers easiness and convenience in use. 
       SUMMARY OF INVENTION 
       [0010]    In light of the shortcomings of the above prior art, it is an object of the present invention to provide a door handle apparatus that remains rotatable when in a lockedstate. 
         [0011]    It is another object of the present invention to provide a door handle apparatus that can only be disassembled when in an unlocked state. 
         [0012]    In order to achieve the above and other objects, the present invention provides a door handle apparatus having a transmission mechanism slidably disposed in a spiral groove of a locking mechanism to achieve conversion of the transmission relationship therebetween by a rigid structure. Additionally, the locking mechanism has a burglarproof locking piece to keep the door handle apparatus from being disassembled when in an unlocked state. In other words, a user needs to unlock the door handle apparatus with a key before it being disassembled from the door. 
         [0013]    The door handle apparatus of the present invention comprises a handle having a pivotal connecting portion and an action portion, the pivotal connecting portion is connected with the action portion and has a through hole penetrating therethrough; a lock housing having a first housing assembly and a corresponding second housing assembly, wherein the handle is pivotally engaged with the first housing assembly, and the center of the second housing assembly is formed with an opening; a locking mechanism comprising at least a core lock, a sleeve cylinder and a locking piece, wherein the core lock is disposed and fastened in the through hole of the handle, the sleeve cylinder, which has a plurality of guiding grooves, is engaged with both the core lock and the first housing assembly and fastened to the core lock, and the locking piece is slidably engaged with the sleeve cylinder and formed with an open slot for moving, via an inner brim, relative to the core lock; and a transmission mechanism having a first transmission assembly slidably engaged with the sleeve cylinder and a second transmission assembly rotatably engaged with the second housing assembly, wherein one end of the first transmission assembly is engaged with the sleeve cylinder and transmits force to move relative to the core lock, a spiral groove and a limiting lever are disposed at positions close to where the core lock is located, wherein the limiting lever is disposed in the spiral groove, and passes through the sleeve cylinder to secure the first transmission assembly in position, and one end of the second transmission assembly passes through the through hole to protrude from the second housing assembly, such that the second transmission assembly transmits force to move relative to the first transmission assembly by engaging the first transmission assembly with the second transmission assembly. 
         [0014]    Preferably, the pivotal connecting portion has a limiting groove connected with the through hole, and the core lock has a limiting bump corresponding to the limiting groove. The core lock, which is engaged with the pivotal connecting portion, enables the limiting bump to wedge in the limiting groove and makes the core lock move when a user rotates the handle. The core lock, when being rotated, pushes the open slot to move the locking piece, and rotates the transmission mechanism at the same time to move axially about the sheath cylinder by the relative movement of the limiting lever and the spiral groove. 
         [0015]    The first housing assembly further comprises an upper lid, a handle base engaged with the upper lid; and a reset ring movably engaged with the handle base and having a plurality of bumps disposed on the inner brim thereof, and the bumps correspond to the guiding grooves, wherein the bumps wedge in the guiding grooves when the sleeve cylinder is assembled into the first housing assembly, allowing the sleeve cylinder to transmit force and move relative to the reset ring. The reset ring has an elastic spring connecting the reset ring with the handle base, enabling the reset ring to spring back to its original position by the elasticity of the spring after being rotated by an external force. 
         [0016]    The first transmission assembly further comprises an upper-lock sheath having a gourd opening for correspondingly coupling to the core lock, wherein the spiral groove of the first transmission assembly is engaged with the upper-lock sheath; and a sliding block with one end being connected with the upper lock sheath the other end being connected with the second transmission assembly, and transmits force to move it, when the first transmission assembly moves. 
         [0017]    The second transmission assembly comprises a shaft penetrating the through hole of the second housing assembly; and a fastening sheath with one end engaged with the shaft and the other end moving relative to the sliding block, wherein at least an elastic positioning member abutting against an inner side of the second housing assembly is engaged with the fastening sheath at positions close to the second housing assembly, and at least a positioning hole corresponding to the moving trajectory of the elastic positioning member is formed on the inner side of the second housing assembly, when the fastening sheath is rotated to move the elastic positioning member to the positioning hole, the elastic positioning member wedges in the positioning hole, thereby holding the second transmission assembly in a predetermined position. The second housing assembly is formed with a plurality of positioning holes on the outer brim, and is connected with the first housing assembly by a plurality of screws. 
         [0018]    Compared with conventional door handle apparatus using an elastic spring to transmit force, the present invention provides a door handle apparatus with a rigid structure to convert the transmission status of connection and disconnection, and eliminating the problem like elastic fatigue associated with prior arts. Additionally, the locking mechanism of the present invention has a burglarproof locking piece that prevents the door handle apparatus from being disassembled without being unlocked by a key first. Thus, the present invention has advantages over conventional techniques and has high industrial applicability. 
         [0019]    In conclusion, the door handle apparatus of the present invention can overcome the problems of prior arts, to allow for broader applications and effective reduction in production costs. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0020]      FIG. 1A  shows an exploded diagram illustrating the structure of a conventional door handle apparatus; 
           [0021]      FIG. 1B  shows an enlarged view illustrating the rotation base of a conventional door handle apparatus; 
           [0022]      FIG. 1C  shows an enlarged view illustrating the transmission base of a conventional door handle apparatus; 
           [0023]      FIG. 2  shows an exploded diagram illustrating the door handle apparatus according to the present invention; 
           [0024]      FIG. 3  shows a cross-sectional diagram illustrating the assemblage of the door handle apparatus with a locking mechanism according to the present invention; 
           [0025]      FIG. 4A  shows a cross-sectional diagram illustrating the assemblage of the handle, the locking mechanism, and the transmission mechanism not in a transmission state according to the present invention; 
           [0026]      FIG. 4B  shows a cross-sectional diagram illustrating the assembly of the handle, the locking mechanism and the transmission mechanism in a transmission state according to the present invention; 
           [0027]      FIG. 5A  shows a cross-sectional diagram illustrating an assembled door handle apparatus according to the present invention; and 
           [0028]      FIG. 5B  shows a cross-sectional diagram illustrating the assembled door handle apparatus with its handle rotated according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0029]    The present invention is described in the following using preferred embodiments, so that one skilled in the art can readily conceive other advantages and effects of the present invention. 
         [0030]    The embodiments of the present invention are illustrated with reference to the following figures. It should be noted that the appended drawings are simplified figures illustrating the basic concept of the present invention, and the elements shown in the drawings are only exemplary and not depicted according to the actual types, numbers, or proportions of the elements, such drawings are intended to be illustrative but not limiting the scope of the invention. 
         [0031]    Referring to  FIG. 2 ,  FIG. 2  is an exploded diagram illustrating the door handle apparatus according to the present invention. As shown in the figure, the door handle apparatus comprises a handle  40 , a lock housing  50 , a locking mechanism  60  and a transmission mechanism  70 . The handle  40  has a pivotal connecting portion  41  and an action portion  42  connected with the pivotal connecting portion  41 , wherein the pivotal connecting portion  41  has a through hole  410  and a limiting groove  411  inside connected with the through hole  410 . The lock housing  50  has a first housing assembly  51  and a corresponding second housing assembly  52 , wherein the handle  40  is pivotally connected with the first housing assembly  51 , and the second housing assembly  52  has an opening  520  in the center and a plurality of fixing holes  521  on the periphery. The locking mechanism  60  has at least a core lock  61 , a sleeve cylinder  62 , and a locking piece  63 , wherein the core lock  61  is disposed and fastened in the through hole  410  of the handle  40 , and has a limiting bump  610  corresponding to the limiting groove  411 . When the core lock  61  is engaged with the pivotal connecting portion  41 , the limiting bump  610  wedges in the limiting groove  411 , so as to allow the handle  40  to be rotated to simultaneously transmit force to the core lock  61 . The sleeve cylinder  62  has a plurality of guiding grooves  620  engaged with the core lock  61 , and are engaged with the first housing assembly  51 , wherein the limiting bump  610  of the core lock  61  wedges in one of the guiding grooves  620  of the sleeve sheath  62 , so as to enable the core lock  61  to move along with rotation of the handle  40  to transmit force to move relative to the sleeve sheath  62 . The locking piece  63  is slidably engaged with the sleeve cylinder  62 , and has an open slot  630  for connecting with the core lock  61  and transmitting force to move, via an inner brim thereof, relative the core lock  61 . The transmission mechanism  70  has a first transmission assembly  71  slidably engaged with the sleeve cylinder  62  and a second transmission assembly  72  rotatably engaged with the second housing assembly  52 , wherein one end of the first transmission assembly  71  is engaged with the sleeve cylinder  62 , and is connected with the core lock  61 . A spiral groove  712  and a limiting lever  713  are disposed at positions close to where the core lock  61  is located, wherein the limiting lever  713  is disposed in the spiral groove  712  and passes through the sleeve cylinder  62  to secure the first transmission assembly  71  in position, while one end of the second transmission assembly  72  passes through the through hole  520  to penetrate from the second housing assembly  52 , such that the second transmission assembly transmits force to move relative to the first transmission assembly by moving the first transmission assembly  71  and engaging it with the second transmission assembly  72 . 
         [0032]    Referring to  FIG. 3 ,  FIG. 3  is a cross-sectional diagram illustrating the assembly of the door handle apparatus with a locking mechanism according to the present invention. As shown in the figure, the sleeve cylinder  62  has a pair of through slots  621 ,  622  corresponding in dimensions to both ends of the locking piece  63  to receive the locking piece  63  therein. Moreover, the sleeve cylinder  62  is further engaged with two protecting pieces  64 , wherein one end of the sleeve cylinder  62  has a fixing slot  640  having a C-shaped ring  65  coupled thereto for allowing the two protecting pieces  64  to be engaged with the sleeve cylinder  62 . Furthermore, the C-shaped ring  65  has an additional function as a retainer, which is described later. When the core lock  61  is rotated, the inner brim of the locking piece  63  has a bump  631  that pushes the slot  630  to move the locking piece  63 ; and when the core lock  61  is connected with the bump  631 , the bump  631  limits the movement of the locking piece  63  in the cylinder  62 . In other words, the locking piece  63  is locked and immovable when the core lock  61  is in a locked state. Since the locking piece  63  is a pivotal action member in a disassembled door handle apparatus, the door handle apparatus cannot be disassembled without a unlocking with a key. 
         [0033]    Referring to  FIGS. 4A and 4B ,  FIG. 4A  is a cross-sectional diagram illustrating the assemblage of the handle, the locking mechanism, and the transmission mechanism not in a transmission state, and  FIG. 4B  is a cross-sectional diagram illustrating the assemblage of the handle, the locking mechanism and the transmission mechanism in a transmission state moving relative to one another. As shown in the figures, the first transmission assembly  71  of the transmission mechanism  70  further comprises an upper-lock sheath  710  and a sliding block  711 . The upper-lock sheath  710  has a gourd opening  7100  for correspondingly coupling to the core lock  61 , wherein a spiral groove  712  of the first transmission assembly  71  is engaged with the upper-lock sheath  710 . One end of the sliding block  711  is connected with the upper lock sheath  710 , while the other end is connected with the second transmission assembly  72  and transmits force to move it, when the first transmission assembly  71  is moved. 
         [0034]    The second transmission assembly  72  comprises a shaft  720  and a fastening sheath  721 . The shaft  720  passes through to be disposed on the through hole  520  of the second housing assembly  52 . One end of the fastening sheath  721  disposed on the shaft  720 , and enables the sliding block  711  to move relative to the fastening sheath  721  when the sliding block  711  is coupled to the fastening sheath  721 , that is, the door handle apparatus is in an unlocked state. 
         [0035]    Referring to  FIGS. 5A and 5B ,  FIG. 5A  is a cross-sectional diagram illustrating an assembled the door handle apparatus, and  FIG. 5B  is a cross-sectional diagram illustrating an assembled door handle apparatus with its handle rotated. As shown in the figures, the first housing assembly  51  further comprises an upper lid  510 , a handle base  511 , and a reset ring  512 . The handle base  511  is engaged with the upper lid  510 . The reset ring  512  is movably engaged with the handle base  511 , and has a plurality of bumps  5120  disposed on the inner brim. The bumps  5120  wedge in the guiding grooves  620 , wherein the bumps  5120  wedge in the guiding grooves  620  when the sleeve cylinder  62  is assembled into the first housing assembly  51 , so as to allow the sleeve cylinder  62  to transmit force and move relative to the reset ring  512 . The reset ring  512  has an elastic spring  5121  connecting the reset ring  512  with the handle base  511 . The reset ring  512 , after being rotated by an external force, springs back to its original position by the elasticity of the spring  5121 . In other words, the handle  40 , after being rotated, is reset to return to its original position by the relative movement in a transmission relationship among the core lock  61 , the sleeve sheath  62  and the reset ring  512 . Moreover, the second housing assembly  52 , is connected with the first housing assembly  51  with a plurality of screws  522 , after passing through the fixing hole  521 . In addition, the fastening sheath  721  is locked to the shaft  720  with a screw  7211 . After passing through the through hole  520  of the second housing assembly  52 , the shaft  720  is coupled to a fixing hole  7200  of the shaft  720  by a C-shaped ring  7201 , after passing through the hole  520  of the second housing assembly  52 , to allow the shaft  720  to be rotatably engaged with the second transmission assembly  52 . 
         [0036]    Furthermore, a pair of elastic positioning members  7210  abutting against an inner side of the second housing assembly  52  is engaged with the fastening sheath  721  at positions close to the second housing assembly  52 , and a pair of positioning holes  523  corresponding to the moving trajectory of the elastic positioning member are formed on the inner side of the second housing assembly  52 . When the fastening sheath  721  is rotated to move the elastic positioning members  7210  to the positioning holes  523 , the elastic positioning members  7210  are fastened to positioning holes  523 , thereby holding the second transmission assembly  72  in a predetermined position. 
         [0037]    Compared with conventional door handle apparatuses using an elastic spring for transmission, the present invention employs a rigid structure to achieve conversion of the transmission status of connection and disconnection, such that the problem of elastic fatigue is eliminated. Additionally, the locking mechanism of the present invention has a burglarproof locking piece that prevents the door handle from being disassembled from a predetermined position without being unlocked with a key first. Therefore, the door handle apparatus of the present invention can sufficiently overcome the drawbacks of the conventional techniques, and has high industrial applicability. 
         [0038]    The invention has been described using exemplary preferred embodiments. However, it is to be understood that the scope of the invention is not limited to the disclosed arrangements. The scope of the claims, therefore, should be accorded the broadest interpretation, so as to encompass all such modifications and similar arrangements.