PATENT ABSTRACT
A locking device for a tape cassette housing of a tape recorder comprises a locking recess and a locking protrusion respectively provided in sides of a tape cassette housing and a deck chassis and corresponding to each other, thereby fastening a tape cassette housing to the deck chassis, the tape cassette housing resiliently coming into contact with the deck chassis as a tape cassette is loaded. In here, around external circumference of the locking protrusion is formed at least one edge, and an end of the edge comes into contact with a corner of the locking recess right before the locking protrusion is inserted into the locking recess. Accordingly, the locking protrusion comes into linear contact with the corner of the locking recess in loading/unloading operations of the tape cassette so that the stopping of the ascending and descending movements of the tape cassette housing is prevented during the loading/unloading operations of the tape cassette.

PATENT DESCRIPTION
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This patent application is a division of U.S. patent application Ser. No. 10/670,345 entitled Locking Device for Tape Cassette Housing of Tape Recorder and filed on Sep. 26, 2003 now U.S Pat. No. 7,199,968, which claims the benefit under 35 U.S.C. § 119(a) to an application entitled “Locking Device for Tape Cassette Housing of Tape Recorder” filed in the Korean Intellectual Property Office on Oct. 8, 2002, and assigned Serial No. 2002-61325, the entire contents of both applications are hereby incorporated by reference. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a tape recorder, and more particularly, to a locking device for locking a tape cassette housing, which comes into resilient and close contact with a deck chassis as a tape cassette is loaded into the deck chassis. 
   2. Description of the Prior Art 
   Generally, a tape recorder having a deck mechanism is an apparatus that records/reproduces audio and/or video information on/from a magnetic tape. Regarding this type of the tape recorder, common examples include a video tape recorder (VTR), a digital audio tape recorder (DAT), and a camcorder. 
     FIG. 1  shows a moving deck  100  of a camcorder. The camcorder is taken as one example of the tape recorder. As shown in  FIG. 1 , the moving deck  100  includes a deck chassis  110 , a tape cassette housing  120 , and a locking device  190  for locking the tape cassette housing  120  onto the deck chassis  110 . In the case of the moving deck  100  which is usually employed for the camcorder, the deck chassis  110  includes a main-chassis  111  and a sub-chassis  112  that reciprocally slides on the main-chassis  111  as a magnetic tape is loaded/unloaded. 
   The tape cassette housing  120  is for loading a tape cassette removably. First and second link members  160  and  170  hinged to both sides of the tape cassette housing  120  are slidably connected to the sub chassis  112 , thereby allowing the tape cassette housing  120  to ascend and descend from and to the sub-chassis  112 . 
   The locking device  190  includes a locking protrusion  195 , a locking recess  197  corresponding to the locking protrusion  195 , and a locking lever  191  hinged to a side of the tape cassette housing  120 . The locking lever  191  is connected to the first link member  160  by a resilient member  180 . The locking protrusion  195  is generally shaped as a cylinder protruding from a side of the locking lever  191 . This locking protrusion  195  is formed by drawing the side of the locking lever  191  or by providing a separate rotatable roller member (not shown) on the side surface of the locking lever  191 . The locking recess  197  is integrally formed with the sub-chassis  112  by cutting a part of a side of the sub chassis  112 . 
   Hereinafter, the descriptions will be made about loading and unloading operations of the tape cassette of the tape recorder as constructed above. 
   A loading operation of the tape cassette is performed as follows: the tape cassette housing  120  housing the tape cassette therein is pressed toward the sub-chassis  112  and thus the locking protrusion  195  of the locking lever  191  is inserted into the locking recess  197  as shown in  FIG. 2 . An unloading operation of the tape cassette is performed as follows: an unlocking lever  117 , pivotably disposed at the sub-chassis  112 , presses an unlocking protrusion  193  formed at an end of the locking lever  191  in a direction so that the locking protrusion  195  is leased from the locking recess  197 . Simultaneously, the first and the second link members  160  and  170  pivot due to a recovery force of the resilient member  180 , and accordingly, the tape cassette housing  120  ascends in a direction in which the tape cassette housing  120  is separated from the sub-chassis. 
   However, it is often the case with conventional tape recorders that the ascending/descending movement of the tape cassette housing is stopped with the locking protrusion  195  being blocked by an edge  197   a  of the locking recess  197  as the tape cassette is loaded/unloaded, as shown in  FIG. 3 . This stoppage occurs since the locking protrusion  195  and the edge  197   a  of the locking recess  197  come into contact with each other at a contact point where stress forces of the locking protrusion  195  and the edge  197   a  are exerted over each other in equilibrium. Stoppage occurs more frequently as the contact time of the locking protrusion  195  and the edge  197   a  increases. Accordingly, there has been a demand for reducing the contact time between the locking protrusion  195  and the edge  197   a  on the loading/unloading operations of the tape cassette. 
   SUMMARY OF THE INVENTION 
   The present invention has been developed in order to solve the above problems in the prior art. Accordingly, an aspect of the present invention is to provide a locking device for a tape cassette housing of a tape recorder having an improved structure capable of preventing stopping of ascending and descending movements of the tape cassette housing during loading/unloading operation of the tape cassette. 
   A further aspect of the present invention is to provide a moving deck of a tape recorder which comprises a deck chassis, the deck chassis comprising a main chassis and a sub-chassis. The moving deck further comprises a tape cassette housing and a locking device for the tape cassette housing of the tape recorder, wherein the locking device comprises a locking lever, the locking lever comprising a guide surface, and is adapted to pivot within a range determined by a regulating protrusion and a second hinge, and hinged to a side of the tape cassette housing by a first hinge, and connected to a first link member by a resilient member, the resilient member adapted to allow the tape cassette housing to resiliently ascend and descend to and from a sub-chassis. Further, the locking device comprises a locking recess formed within the locking lever and a locking protrusion, integrally formed on a sub-chassis, adapted to be inserted into the locking recess so as to lock the tape cassette housing onto a sub-chassis in a close contacting manner. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above aspects and features of the present invention become more apparent by describing certain embodiments of the present invention with reference to the accompanying drawings, in which: 
       FIG. 1  is an exploded perspective view schematically showing a moving deck of a conventional camcorder; 
       FIG. 2  is a side section view showing the tape cassette housing of  FIG. 1  being locked onto the deck chassis; 
       FIG. 3  is a side section view showing the tape cassette housing of  FIG. 1  seated on the deck chassis; 
       FIG. 4  is a side section view magnifying part of A of  FIG. 3 ; 
       FIG. 5  is an exploded perspective view schematically showing a moving deck according to a first embodiment of the present invention; 
       FIG. 6  is a side section view showing the tape cassette housing of  FIG. 5  seated on the deck chassis; 
       FIG. 7  is a perspective view magnifying part of B of  FIG. 6 ; 
       FIG. 8  is an exploded perspective view schematically showing a moving deck according to a second embodiment of the present invention; 
       FIG. 9  is a side section view showing the tape cassette housing of  FIG. 8  seated on the deck chassis; and 
       FIG. 10  is a perspective view magnifying part of C of  FIG. 9 . 
   

   DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
   Hereinbelow, various embodiments of the present invention will be described in greater detail with reference to the accompanying drawings. Meanwhile, with respect to elements identical to those of the conventional tape recorder shown in and described through  FIGS. 1 through 4 , like reference numerals are assigned, and the detail descriptions thereof will be omitted. 
   Referring to  FIG. 5 , a moving deck  100  of a tape recorder according to an embodiment of the present invention is shown and includes a deck chassis  110 , a tape cassette housing  120 , and a locking device  200  for the tape cassette housing. 
   The deck chassis  110  includes a main-chassis  111  and a sub-chassis  112 . On the main-chassis  111  are provided a loading motor  130  and a capstan-driving unit  140 , and on the sub-chassis  112  is provided a pair of reel tables  150 . 
   The tape cassette housing  120  removably houses a tape cassette (not shown). First and second link members  160  and  170 , pivotably disposed at both sides of the tape cassette housing  120 , are slidably mounted on the sub-chassis  112 , so that the tape cassette housing  120  can ascend from, and descend to, the sub-chassis  112 . Each of the first link members  160  is hinged to the tape cassette housing  120  using a first hinge  163 . Respective upper ends of the first link members  160  are connected to each other via a connecting member  165 . Each of the first link members  160  is provided with a first guide rail  161 , disposed at a lower end thereof. The first guide rail  161  is slidably connected to a first guide protrusion  115  of the sub-chassis  112 . The second link members  170  are hinged to the first link members  160  using second hinges  173 . Each of the second link members  170  has a mounting protrusion  125  formed at a lower end thereof to be inserted into a mounting opening  113  of the sub-chassis  112 . Upper ends of the second link members  170  are provided with second guide rails  171  into which second guide protrusions  121  protruding from both sides of the tape cassette housing  120  are inserted. In one embodiment, it is preferred that the second hinges  173  protrude from the second link member  170  to a predetermined height, though other configurations can be implemented, and the description thereof will be made below. 
   The locking device  200  includes a locking protrusion  220 , a locking lever  210 , and a locking recess  230 . The locking protrusion  220  is integrally formed with the sub-chassis  112  and has at least one edge  220   a . The formation of the edge  220   a  is achieved by forming the locking protrusion  220  with a non-circular traverse section. In this embodiment, the locking protrusion  220  is formed by cutting and bending at or about 90° a part of the sub-chassis  112  toward the inside of the sub chassis  112 . Accordingly, the edges  220   a  are formed at both sides of the locking protrusion  220 . As described above, when forming the locking protrusion  220  integrally with the sub-chassis  112 , the relatively complicated drawing process for the conventional locking lever  191  (described in reference to  FIG. 1 ), or installation of a separate roller member (not shown) is not required. In one embodiment of the invention, the locking protrusion  220  is formed in a shape so that a corner  230 A of the locking recess  230  comes into contact with the edge  220   a  right before the locking protrusion  220  is inserted to the locking recess  230  in the loading operation of the tape cassette. Other shapes of locking protrusion  220  can be used in accordance with other embodiments of the invention. 
   The locking lever  210  is hinged to a side of the tape cassette housing  120  using a third hinge  212 . The upper end of the locking lever  210  is connected to one of the first link members  160  by a resilient member  180 . Due to the resilient member  180 , the tape cassette housing  120  is capable of resiliently ascending and descending for the close contacting with, and separation from, the sub-chassis  112 . One side of the locking lever  210  is provided with the locking recess  230  into which the locking protrusion  220  is inserted so as to lock the tape cassette housing  120  onto the sub-chassis  112  in a close contacting manner. The corner  230   a  of the locking recess  230  is connected to a guide surface  217  extending from the lower end of the locking lever  210 . The locking lever  210  pivots within a range that is determined by a regulating protrusion  127 , protruding from a side of the tape cassette housing  120 , and a second hinge  173 , protruding from the second link member  170  to a predetermined height. Accordingly, excessive pivoting movement of the locking lever  210  due to the recovery force of the resilient lever  210  can be prevented. Meanwhile, an unlocking protrusion  213  protrudes from a lower end of the locking lever  210 . The unlocking protrusion  213  comes into contact with an end of the unlocking lever  117 , pivotably disposed on the sub-chassis  112 , when the tape cassette housing  120  is locked. Operation of the unlocking protrusion  213  will be described below. 
   Hereinafter, loading/unloading operations of the tape cassette housing as constructed above according to various embodiments of the present invention will be described with reference to the accompanying drawings. 
   A loading operation of the tape cassette is performed by pressing an upper surface of the tape cassette housing  120  toward the deck chassis  110 . Accordingly, the second link members  170  pivot along the second guide protrusions  121  in a direction in which the lower end of the first link members  160  ascends. Since the first guide protrusions  115  of the sub-chassis  112  are slidably connected to the first guide rails  161  of the lower ends of the first link member  160 , the interactive movement of the first and the second link members  160  and  170  allows the tape cassette housing  120  to closely contact the sub-chassis  112 . 
   When the tape cassette housing  120  descends in close contact with the sub-chassis  112  as described above, the guide surface  217  of the locking lever  210  comes into contact with the edge  220   a  formed at a side of the locking protrusion  220  and having an angled end as shown in  FIG. 6 . In this state, the descending movement of the tape cassette housing  120  continues so that the edge  220   a  of the locking protrusion  220  is guided toward the locking recess  230  and comes into contact with the corner  230   a  of the locking recess  230  (i.e. a boundary between the guide surface  217  and the locking recess  230 ). Since the guide surface  217  is inclined, the locking lever  210  pivots on the third hinge  212  in a direction of the arrow of  FIG. 6 , so that there occurs a recovery force in the resilient member  180 . Accordingly, when the tape cassette housing  120  completely contacts the sub-chassis  112 , the locking lever  210  pivots in an opposite direction to the arrow direction of  FIG. 6 , due to the recovery force of the resilient member  180  so that the locking protrusion  220  is inserted into the locking recess  230 . At this point, the edge  220   a  and the corner  230   a  come into linear contact with each other as shown in  FIG. 7 . The linear contact reduces both contacting space and time. Accordingly, a “dead” point at which the conventional tape cassette housing  120  stops its movement can be prevented. 
   Meanwhile, when the user selects the ejection of the tape cassette, an unlocking switch  135  is operated so that a rod  135   a  disposed in a side of the unlocking switch  135  protrudes by more than a predetermined distance. Due to the operation of the unlocking switch  135 , the unlocking lever  117  pivotably disposed at the sub-chassis  112  pivots to press the unlocking protrusion  213  protruding from the end of the locking lever  210  in a direction in which the locking protrusion  220  is released from the locking recess  230 . The unlocking protrusion  213  is pressed by the unlocking lever  117  to thus pivot the locking lever  210  in the direction of the arrow of  FIG. 6  and accordingly, the locking protrusion  220  is released from the locking process  230 . After that, due to the recovery force of the resilient member  180 , the tape cassette housing  120  automatically ascends. Simultaneously, the locking lever  210  pivots until its pivotal movement is limited by the regulating protrusion  127 , so that the unloading operation of the tape cassette is completed. 
   The locking device  200  of the tape cassette housing  120  as constructed and operated above is limited to the embodiment described above. If the edge  220   a  of the locking protrusion  220  contacts with the corner  230   a  of the locking recess  230  in the loading/unloading operations of the tape cassette, the locking recess  230 , the locking protrusion  220 , and the locking lever  210  can be varied in their installation positions and shapes. 
     FIGS. 8 to 10  are views showing a deck  100  for a tape recorder having a tape cassette housing locking device  200 ′ according to another embodiment of the present invention. The tape cassette housing locking device  200 ′ in this embodiment has the substantially same construction as that of the above-described embodiment, except that a locking protrusion  220 ′ is modified in shape and there is no need for the installation of the unlocking lever  117  (described in reference to  FIG. 5 ), because an unlocking protrusion  213 ′ comes into contact directly with the unlocking switch  135  as the tape cassette housing  120  is locked. 
   The locking protrusion  220 ′ differs from the locking protrusion  220  of the above-described embodiment in that a side end of the locking protrusion  220 ′ is bent inward at or about 90° toward the deck  100  to be inserted into a locking recess  230 ′. 
   As described above, modifying the bending portion and bending direction of the locking protrusion  220 ′, prevents errors in combining the locking protrusion  220 ′ and the locking recess  230 ′. These errors are caused by the deformation of the upper portion of the locking protrusion  210  that occurs by the frequent contact of the locking recess  230  and the locking protrusion  210 . 
   The elements and operations of the deck  100  are identical to that of the above-described embodiment, and descriptions thereof will be omitted. 
   Also, although the descriptions of the various embodiments of the invention have been limited to the camcorder employing the moving deck  100 , the various embodiments of the present invention can be applied to any type tape recorder. This includes, for example, a video tape recorder (VTR), if it employs the tape cassette housing  120  resiliently contacting to, and separating from, the deck chassis  110 . even in the absence of the moving deck  100 . 
   According to the various embodiments of the present invention as described above, the stopping of the ascending and descending movements of the tape cassette housing  120  due to the interference between the locking recess  230  and the locking protrusion  220  is prevented during loading/unloading operations of the tape cassette. 
   The foregoing embodiments and advantages are merely exemplary and are not to be construed as limiting the present invention. The present teaching can be readily applied to other types of apparatuses. The description of the various embodiments of the present invention is intended to be illustrative, and not meant to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures.