Abstract:
Disclosed herein is a two stage compressive spring operated door check hinge. It has two springs of different length equipped along an outer tube to serve two stage restoring force. A unique design of collaborated function of the set billets and the corresponding containment holes enable the door to pause at a desired position. An adjustable nut is provided to adjust the elastic force of two springs such that the operation of the door can be carried out smoothly and silently without installing an awkward articulated door check arm.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a two stage compressive spring operated door check hinge, and more particularly, to a door check hinge equipped with an inner and an outer compressive springs, one, or a plurality of set billets and their containment holes formed at the bottom of the door hinge, so as to operate the door to move in stages and be positioned thereat.  
           [0003]    2. Description of the Prior Art  
           [0004]    FIGS.  1 (A) and  1 (B) respectively show schematic views of a conventional automatic restoring door check hinge and an articulated door check arm operating in collaboration with the automatic restoring door check hinge. As shown in FIG. 1(A), an automatic restoring door check hinge  700  is provided with two wing plates  710  in two sides. Each of the two door wings  710  has a sleeve whose upper and lower portions are separated by a spacer. The two wing plates  710  commonly own a hinge pin  720  wound by a compressive spring  730  each its terminal is secured to respective wing plate  710  such that both wing plates  710  are tamable with respect to the hinge pin  720  thereby opening/closing the door.  
           [0005]    To shut an open door unforcibly and silently, an articulated door check  800  as shown in FIG. 1B is conventionally equipped on the upper portion of the door and the door frame so as to automatically close the door silently and slowly with the aid of a restoring spring force. But the open door is usually limited to not wider than an open angle of 80:  
           [0006]    However, a conventional compressive spring door hinge associated with the articulated door check arm for automatic door close operation described above has the following shortcomings:  
           [0007]    1. The outwardly equipped compressive spring will yield and loose its restoring elasticity after being in use for long time.  
           [0008]    2. Replacement for existing spring is impossible, even it is not easy to adjust its elastic force.  
           [0009]    3. An oil pressure operated door check fails due to oil leakage after repeated operation, moreover, awkward construction of two articulating aims for the door check spoils outerlook of a door.  
           [0010]    4. The door check with this structure is fragile and not easy for regular maintenance as well.  
           [0011]    In view of above facts, a new check which can palliate the disadvantages of conventional products is definitely necessary. The present inventor has delved into this matter with long time effort and come to realization of the present invention.  
         SUMMARY OF THE INVENTION  
         [0012]    It is an object of the present invention to provide a two stage compressive spring operated door check hinge which can stably turn for opening and closing the door in two stages silently by compressive spring force.  
           [0013]    It is another object of the present invention to provide a two stage compressive spring operated door check hinge which is simply constructed without an articulated arm so as to facilitate assembling, installation and regular maintenance.  
           [0014]    To achieve the above mentioned objects, the door check hinge according to the present invention carries our smooth turning by means of sliding movement of screw rails in spiral grooves. And, two stage movement of the door is carried out by a two stage restoring force produced by two compressing springs associated with set billets and their containment holes formed at the bottom portion of the door check hinge, and enable the door to pause at a prescribed open angle (for example 80°)  
           [0015]    The above objects and other advantages of the present invention will become more apparent by describing in detail the preferred embodiment of the present invention with reference to the attached drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    [0016]FIG. 1A is a schematic view of a conventional automatic restoring door check hinge.  
         [0017]    [0017]FIG. 1B is a schematic view of an articulated door check arm operating in collaboration with the automatic door check hinge of FIG. 1A.  
         [0018]    [0018]FIG. 2 is an exploded view of the two stage compressive spring operated door check hinge according to the present invention.  
         [0019]    [0019]FIG. 3 is a cross sectional view of the two stage compressive spring operated door check hinge of the present invention when the door is closed.  
         [0020]    [0020]FIG. 3A is a partial schematic view of the slide blocks and the compressive springs shown in FIG. 3.  
         [0021]    [0021]FIG. 4 is a cross sectional view showing the inner spring is in compressed state when the door hinge is open in an embodiment of the present invention.  
         [0022]    [0022]FIG. 4A is a partial schematic view showing the state of the springs and the slide blocks in FIG. 4.  
         [0023]    [0023]FIG. 5 is a cross sectional view showing that both spring elements are simultaneously compressed to actuate the set billets when the door hinge is open a certain angle in an embodiment of the present invention.  
         [0024]    [0024]FIG. 5A is a partial schematic view showing the state of the springs and the slide blocks in FIG. 5. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0025]    The operation of the conventional articulated door check arm operating in collaboration with the automatic door check hinge has been described above and will not be repeated herein.  
         [0026]    Referring to FIGS. 2 and 3 simultaneously, the two stage compressive spring operated door check hinge of the present invention comprises: a base tube  80 , an outer tube  70 , a cylindrical slide block  51 , a pair of upper and lower spacer block  31  and  32 , the upper lid  23 , and a fixing nut  21  associated with an adjustable nut  22  and a cap  10 .  
         [0027]    The base tube  80  has a stationary wing plate at its side thereof for securing to the door body. A pad  63  of smaller diameter is formed at the upper end of tube  80  thereof. From the center of the pad block  63  there is a center pin  60  of even smaller diameter extending upwardly. A pair of symmetrically disposed guide tracks  61 ,  62  are formed at both sides of the lower end of the center pin  60 . Several vertical via holes  81  are formed approximately equally apart of each other along the longitudinal direction through the body of the base tube  80  outside of the pad block  63  for screw engaging with respective spring elements  82  by screw threads provided at the top portion of the via holes  81  and on the spring elements  82 . A set billet  82 - 1  is provided for each spring element  82  on its top end thereof and is movable up and down in the via hole  81  by spring force.  
         [0028]    The outer tube  70  has a butterfly wing  71  formed at one side thereof for securing to the door frame. The outer tube  70  has a diameter able to let it sleeve over and enclose the base tube  80  up to the upper end of the base tube  80 . A pair of symmetrical spiral grooves  52 - 1 ,  52 - 2  is formed in its lower inner tubular cavity. Equal number spherical containment holes  63 - 1 ,  63 - 2  . . . aimed at the corresponding positions of the set billets  82 - 1  are formed on the bottom of the tube body for permitting the set billets  82 - 1  to enter after being flicked up by the spring element  82 .  
         [0029]    The cylindrical slide block  51  having several through holes formed at its center portion is inserted into the center pin  60  and the guide tracks  61 ,  62  of the base tube  80 . A pair of symmetrical spiral rails  51 - 1 ,  51 - 2  is formed on its outer wall surface such that it is able to relatively slide with the outer tube  70  by mating the spiral rails  51 - 1 ,  51 - 2  with the spiral grooves  52 - 1 ,  52 - 2  after being conjoined to the outer tube  70 .  
         [0030]    The lower spacer block  32  is configured into a protruded tube body for mounting on the top end of the cylindrical slide block  51  after being sleeved into the center pin  60 . The inner part thereof is for equipping an inner spring  41 , while the outer part thereof is for equipping an outer spring  42 .  
         [0031]    The upper spacer block  31  is a downwardly protruded tube body mounted on top of the lower spacer block  32 . It consists of an inner tube  31 - 1  and a pad block  31 - 2 . The inner spring  41  is equipped in the inner tube  31 - 1 , while the outer spring  42  is in contact with the pad block  31 - 2 , and the two springs  41  and  42  are isolated by the inner tube  31 - 1 . The inner spring  41  is longer than the outer spring  42 .  
         [0032]    The upper lid  23  has a hole at its center for letting through the center pin  60  and covers the top of the outer tube  70 .  
         [0033]    The fixing nut  21 , the adjustable nut  22 , and the cap  10  are screw engaged with the center pin  60  by the screw threads  64  provided on the center pin  60 . The height of the pad block  31 - 2  can be adjusted by the adjustable nut  22 . Also the restoring force of the springs  41  and  42  can be controlled by adjusting the length of the two springs  41  and  42  through tightening or loosening the adjustable nut  22  so as to meet the requirements of various situations.  
         [0034]    As shown in FIG. 3, before the hinge is closed or opened to a prescribed angle, the set billet  82 - 1  on the spring element  82  in the vertical via hole  81  is under the compressed state. As soon as the hinge has reached an open angle of (for example 90°), the spring element  82  flicks the set billet  82 - 1  into the containment hole  63 - 1  ( 63 - 2 ) thereby halting movement of the butterfly hinge  71 .  
         [0035]    Referring to FIGS. 4 and 4A, in an embodiment of the present invention, when an external force is applied to the hinge for turning preferably within the range of 15°, the outer tube  70  follows to move and causes a relative slide motion between the spiral slide grooves  52 - 1 ,  52 - 2  on the inner wall of the outer tube  70  and the spiral rails  51 - 1 ,  51 - 2  of the cylindrical slide block  51  such that the slide block  51  ascends along the slide tracks  61 ,  62  to compress the inner spring  41  causing it to produce a restoring force.  
         [0036]    After the turning angle of the hinge has exceeded the preferable angle 15°, the slide block  51  begins to compress the outer spring  42  such that the outer spring  42  produces a restoring force.  
         [0037]    Referring to FIGS. 5 and 5A, when the turning angle has reached an angle preferably 90°, the vertical via holes  81  are aligned to the containment holes  63 - 1 ,  63 - 2  . . . , and the spring elements  82  are loosened to flick the set billets  82 - 1  into the containment holes  63 - 1 ,  63 - 2  thereby halting the movement of the hinge.  
         [0038]    It is understood form the above description that the two stage compressive spring operated door check hinge has several noteworthy advantages, in particular:  
         [0039]    (1) The different length of the two springs  41  and  42  can be properly adjusted with the adjustable nut  22  before use so as to avoid door noise.  
         [0040]    (2) Relative slide notion between the spiral slide grooves  52 - 1 ,  52 - 2  of the outer tube  70  and the spiral rails  51 - 1 ,  52 - 2  of the slide block  51  contributes to smooth and stable door operation.  
         [0041]    (3) For adjustment to obtain a proper door operation speed and applicable force, firstly the fixing nut  22  may be loosened to separate its lower end from the top end of the adjustable nut  22 , by turning the adjustable nut  22  to move the upper spacer block  31  which in turn presses or releases the spring  41  and  42 , after the desired adjustment is attained, turning tightly the fixing nut  21  to make its lower end forcibly in contact with the upper end of the adjustable nut  22 , by so the operation noise can be refuced.  
         [0042]    (4) Replacement of inner and outer springs  41  and  42  are so easy that the existing spring can be taken out only by detaching the fixing nut  21 , adjustable nut  22 , and the upper lid  23 .  
         [0043]    (5) the two stage restoring force for the door hinge is obtained by the two springs  41  and  42  equipped along the outer tube  70 . Besides, unique design of collaborated action of the set billets and the containment holes enables the door to pause at a desired position.  
         [0044]    Only a preferred embodiment of the present invention is shown and desired herein. It is to be understood that the present invention is capable of changes or modification or combination within the scope of inventive concept as expressed herein.