Patent Publication Number: US-2012042474-A1

Title: Door mechanism

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to Israel Patent Application No. 207238 filed on 26 Jul. 2010, the contents of which are incorporated herein, in their entirety, by this reference. 
     TECHNICAL FIELD 
     Embodiments of the invention relate to mechanisms for retaining a door in an open position, and in particular for mechanisms for use with doors for armored vehicles. 
     BACKGROUND 
     In vehicles, it is well known to provide a hinge mechanism associated with one or more doors thereof in order to facilitate opening/closing thereof, and/or to maintain the door in an open position by a retention mechanism. In armored vehicles, the door is typically heavier than in non-armored vehicles, and it is typically required that such mechanisms be designed to maintain a heavy door in an open position, even when the vehicle is on an incline or overturned. 
     There are known various retention mechanisms which operate in conjunction with hinge mechanisms. Examples of such mechanisms are discloses in U.S. Pat. No. 6,938,303, EP 1,306,505, and FR2655084. 
     SUMMARY 
     According to one aspect of the presently disclosed subject matter, there is provided a retention mechanism for a hinge mechanism of a door. The hinge mechanism being configured for articulating a door to the sidewall of a vehicle so as to enable pivoting of the door relative to the sidewall about an axis between a closed position and an open position. The retention mechanism comprises:
     a. a first portion comprising a keeper and a biasing arrangement configured to bias the keeper toward a locking position, while allowing displacement of the keeper from the locking position to a disengaged position;   b. a second portion comprising a latch, the latch being configured to displace the keeper from its locking position to its disengaged position and comprising a seat for retaining the keeper therein in its locking position, so as to maintain the door in its open position when the keeper being retained in the seat;   

     The retention mechanism, when operating in conjunction with the hinge mechanism, comprises a clearance area in which, during pivoting of the door between its closed and open positions, there is no contact between the keeper and the latch. 
     When the door is pivoted between its closed and open positions, the latch can be configured to pass through the clearance area between a first position in which the keeper and the latch are maximally distant from each other, and a second position in which the latch comes in contact with the keeper, the latch being configured for assuming a plurality of medial positions, in each of which, there is no contact between the latch and the keeper. 
     At the second position of the latch, the door can be configured to be in an intermediate position between the open position and the closed position of the door, and angled at a first angle with respect to the latter, and at its open position, the door can be rotated at a second angle with respect to its closed position, differing from the first angle. 
     The first position of the latch can be corresponding to the closed position of the door, and the second position of the latch can be corresponding to the intermediate position of the door. 
     The first angle can be between 20 to 50 degrees, and more specifically about 35 degrees. 
     The second angle can be between 50 to 80 degrees, and more specifically about 70 degrees. 
     The clearance area can be configured to provide pivoting of the door between its closed position to its intermediate position, while keeping the latch and the keeper at a contact-free configuration. 
     The retention mechanism can be configured for being attached to an exterior side of a vehicle. 
     The first and second portions can be isolated from one another in the closed position of the door. 
     The biasing arrangement can comprise: 
     a. a biasing plate configured to bear against the keeper; and 
     b. a spring configured to bias the biasing plate toward the keeper. 
     The first portion can comprise a housing configured to constrain the keeper to linear motion. 
     The retention mechanism can further comprise a first plate and a second plate articulated to one another by the hinge mechanism, each of the first and second portions being rigidly mounted to the plates, correspondingly. 
     The first and second plates can be configured to be attached to the door and the sidewall of the vehicle, correspondingly. 
     According to another aspect of the presently disclosed subject matter, there is provided a hinge mechanism configured for articulating a door to the sidewall of a vehicle so as to enable pivoting of the door relative to the sidewall about an axis, the mechanism comprising:
     a. a first portion comprising a keeper and a biasing arrangement configured to bias the keeper toward a locking position, the first portion being configured to allow displacement of the keeper from the locking position; and   b. a second portion comprising a latch, the latch being configured to displace the keeper from its locking position and comprising an open seat for retaining the keeper therein in it locking position;
 
the mechanism being configured for maintaining the door in an open position when the keeper is retained in the seat.
   

     The hinge mechanism may be configured for being attached to an exterior side of the vehicle. 
     The seat may be, in both the open and closed positions of the door, open toward the exterior of the vehicle. 
     The first and second portions may be isolated from one another in the closed position of the door. 
     The keeper may be biased in a direction toward the axis. 
     The keeper may comprise a cylindrical portion. 
     The biasing arrangement may comprise:
         a. a biasing plate configured to bear against the keeper;   b. at least one plunging rod connected to the biasing plate; and   c. a spring associated with each plunging rod configured to bias the biasing plate toward the keeper.       

     The first portion may comprise a housing configured to constrain the keeper to linear motion. The housing may comprise slots sized so as to allow the keeper to slide therewithin and configured for the constraining. 
     The latch may comprise a cam surface configured for the displacing of the keeper. The cam surface may be adjacent the seat. 
     The hinge mechanism may further comprise a first plate and a second plate articulated to one another by a hinge at the axis, each of the first and second portions being rigidly mounted to one of the plates. The hinge mechanism may be free of any element between the first portion and the hinge. The first portion may be mounted adjacent to the hinge. Each of the first and second plates may be configured to be attached to one of the door and sidewall of the vehicle. 
     The door may be an armored door. 
     The vehicle may be an armored vehicle. 
     According to another aspect of the presently disclosed subject matter, there is provided a vehicle comprising a hinge mechanism as per the above. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to understand the invention and to see how it may be carried out in practice, an embodiment will now be described, by way of a non-limiting example only, with reference to the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a retention mechanism mounted on a hinge mechanism in a closed position of a door; 
         FIG. 2  is a perspective view of a retention mechanism mounted on the hinge mechanism illustrated in  FIG. 1 , in an open position of the door; 
         FIG. 3  is a perspective view of a biasing arrangement of the retention mechanism illustrated in  FIGS. 1 and 2 , with its housing removed for purposes of illustration; 
         FIG. 4  is an upper view of the retention mechanism mounted on the hinge mechanism of  FIG. 1  in a closed position of a door, with its housing removed for purposes of illustration; 
         FIG. 5  is an upper view of the retention mechanism mounted on the hinge mechanism of  FIG. 1  in an intermediate position of a door, with its housing removed for purposes of illustration; and 
         FIG. 6  is an upper view of the retention mechanism mounted on the hinge mechanism of  FIG. 1  in an opened position of a door, with its housing removed for purposes of illustration. 
         FIGS. 7A-C  illustrate another examples of the retention mechanism of  FIG. 1  operating in conjunction with a hinge mechanism. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Reference is first made to  FIGS. 1 and 2 , illustrating a hinge mechanism  10  having a retention mechanism  11  mounted thereon. The hinge mechanism  10  is designed to hingedly articulate a door (not shown) to the sidewall of a vehicle (not illustrated), for example an armored door to an armored vehicle, so as to enable pivoting of the door relative to a sidewall of the vehicle about an axis X. The hinge mechanism  10  is designed and configured to be mounted and/or installed on the exterior side of the vehicle, i.e., on the exterior sides of the door and sidewall. 
     The retention mechanism  11  comprises a first portion  12  and a second portion  14 , each of which is attached to plates  16  and  17  which are designed for attachment to one of the doors and its respective sidewall of the vehicle. The plates  16  and  17  are articulated to one another about a hinge  18 , between an open position of the door ( FIG. 2 ) and a closed position of the door ( FIG. 1 ). The hinge  18  is coincident with and rotates about the axis X. Alternatively, the retention mechanism  11  may be designed such that the first and second portions  12 ,  14  may be attached directly to the door and sidewall without the necessity of providing the plates  16  and  17 . 
     In the closed position of the door, the first and second portions  12 ,  14  may be isolated from one another, i.e., they only contact one another when the door is being brought into or out of its open position, and in the open position itself. 
     As best seen in  FIG. 3 , the first portion  12  comprises a keeper  20  being generally cylindrical and designed for retaining a corresponding element of the second portion  14 , as will be explained below. As illustrated, the keeper  20  may comprise a cylindrical central portion  21  and rollers  23  at ends thereof, separated from the central portion by gaps  25 . 
     A housing  22  (not illustrated in  FIG. 3 ) of the first portion  12  is provided to contain the other element thereof. The housing  22  comprises slots  24  constraining the keeper  20  to sliding, e.g., linear, motion between a locking position (as illustrated in  FIGS. 1 ,  2 , and  3 ) and a disengaged position. The significance of these positions will be explained below. The slots  24  are formed so as to cooperate with the rollers  23  of the keeper  20  to ensure smooth motion thereof therein. 
     A plunger mechanism, which is generally indicated at  26 , constituting a biasing arrangement, is provided to bias is provided in order to bias the keeper  20  toward the locking position in a direction toward the axis X, while allowing it to be displaced therefrom. 
     The plunger mechanism  26  comprises a biasing plate  28  configured to bear against the keeper  20 , and three compression springs  32 , disposed between the biasing plate  28  and the housing  22 . The biasing plate  28  is formed with a biasing portion  28   a  for the bearing, and two extensions  28   b  sized so as to be received within the gaps  25  of the keeper  20 , thus restricting axial motion thereof. 
     The housing  22  is further provided with flanges  36  facilitating rigid attachment of the first portion  12  to the plate  17  (or directly to the vehicle door or sidewall, if the retention mechanism  11  is designed to be attached directly to the vehicle), for example via bolts  38 . 
     The second portion  14  comprises a latch  40  (not seen in  FIG. 2 ) configured to cooperate with the keeper  20  for maintaining the door of the vehicle in an open position. As such, it comprises an open, concave seat  42  corresponding with the keeper  20  of the first portion  12 , and a cam surface  44  designed to displace the keeper  20  from its locking position and being located adjacent the seat  42 . The seat  42  is disposed such that it always faces toward the exterior of the vehicle. 
     The seat  42  is formed as an arc having a radius of curvature which is the same or slightly larger than that of the cylindrical central portion  21  of the keeper  20 . As such, when the keeper  20  is retained therein (in the open position of the door), a large amount of force is required to pivot the door about the axis X. 
     The second portion  14  is further provided with flanges  46  facilitating rigid attachment thereof the plate  16  (or directly to the vehicle door or sidewall, if the retention mechanism  11  is designed to be attached directly to the vehicle), for example via bolts  48 . 
     The second portion  14  may be further provided with a cushioning arrangement  50  disposed above the latch  40  (i.e., on the opposite side thereof from the axis X). The cushioning arrangement  50  is located so as to strike the housing  22  of the first portion  12  when the door is brought into its open position, thereby serving as an energy absorber, reducing noise and extending the useful life of the hinge mechanism  10 . 
     The cushioning arrangement  50  may be made of any suitable material, such as rubber, foam, etc. In addition, it may be attached to the second portion  14  by screws  52 , facilitating easy replacement thereof. 
     Reference is now made to  FIGS. 4 ,  5  and  6 , illustrating various stages of operation of the door and of the retention mechanism  11 . The various stages of operating the door include the following positions: a closed position ( FIG. 4 ) in which the keeper  20  and the latch  40  are not in contact with each other, an intermediate position ( FIG. 5 ) in which the latch  40  is in contact (i.e., tangential) with the cylindrical portion  21  of the keeper  20 , and an open position ( FIG. 6 ) in which the cylindrical portion  21  is seated within the seat  42 . 
     With particular reference to  FIG. 4 , which illustrates the closed position of a vehicle&#39;s door, the first and the second portions  12  and  14  are isolated from one another, and the latch  40  is disposed at its first position. In this closed position of the door and first position of the latch  40 , the plates  16  and  17  are generally parallel/co-planar with one another, the latch  40  of the second portion  14  is separate, and maximally distant from the keeper  20  and its cylindrical central portion  21  of the first portion  12 , and the keeper  20  is biased in its locking position. In the first position of the latch, a first point  45   a  of the cam surface  44  is maximally distant from a second point  45   b  of the cylindrical portion  21 . 
     In addition, a clearance area  13  is observed in the form of a sector of a circle having a predetermined angle α, in which, during pivoting of the vehicle&#39;s door between its closed and open positions, no contact between the keeper  20  and the latch  40  takes place. The value of the angle α can be, for example, between 20 to 50 degrees, more particularly between 25 and 40 degrees and even more specifically about 35 degrees. 
     During the first stage of opening of the door, the door, and subsequently the latch  40  attached thereto revolve about the axis X toward the cylindrical central portion  21  of the second portion  12 . At this stage, the latch  40  passes along the clearance area  13 , and this provides a contact-free configuration of the door between its closed and intermediate positions. The term ‘contact-free’ means that there is no mechanical contact and friction between the keeper  20  and the latch  40 . During the pivoting of the door between its closed and intermediate positions, the latch  40  assumes a plurality of medial positions, in each of which, there is no contact between the latch  40  and the keeper  20 . 
     At the end of the first stage of opening the door, it takes its intermediate position, as illustrated in  FIG. 5 . In this position, the first and the second portions  12  and  14  are in contact with each other, and the latch  40  is disposed at its second position. In this second position of the latch  40 , its cam surface  44  is tangential to the cylindrical portion  21  of the keeper  20 , so that first and second point  45   a  and  45   b  are in contact with each other. In this figure, the door which is disposed at its intermediate position, between the open and the closed positions, is rotated (angled) at a first angle with respect to its closed position. The size of the first angle equals to the predetermined angle α of the clearance area  13 . Therefore, its value can be also between 20 to 50 degrees, and more specifically 35 degrees. 
     When the latch  40  is disposed at the clearance area  13 , between its first and the second positions, not including the second position, the first and second portions  12  and  14  are isolated from one another. Only when the latch  40  takes the second position, a contact between its cam surface  44  and the cylindrical portion  21  is created, and from this position, towards to closed position of the door, the pivoting of the door is not contact-free. 
     At a subsequent, second stage of opening the door, the latch  40  is already in contact with the cylindrical portion  21  of the keeper  20 , and the cam surface  44  thereof urges the keeper  20  away from its locking position toward the disengaged position. 
     During this stage, the compression springs  32  are slightly compressed. Once the keeper  20  clears the cam surface  44 , the compression springs  32  force the return of the keeper  20  toward its locking position, wherein it rests within the seat  42 , thereby maintaining the door in an open position. 
     In  FIG. 6 , which illustrates the open position of a vehicle&#39;s door, the first and the second portions  12  and  14  are in contact with each other, and the cylindrical portion  21  of the keeper  20  is disposed at the seat  42  of the latch  40 . In this figure, the door is rotated at a second angle β with respect to its closed position. The second angle is different from the first angle α. The value of the second angle β can be, for example, between 20 to 50 degrees, and more specifically 70 degrees. From the open position, a great deal of force is necessary to displace the cylindrical central portion  21  of the keeper  20  from the seat  42 . This is at least partially due to the geometry of the leading edge  42   a  of the seat, which comprises an abrupt change of angle between the seat  42  and the cam surface  44  of the latch  40  immediately adjacent it. Once the necessary amount of force which acts to urge the door toward its closed position is supplied, the above takes place in reverse. Namely, the keeper  20  is displaced from its locking position toward its disengaged position, allowing the latch  40 , and thus the door, to begin to move toward its intermediate and then to its closed position. As the door closes, the keeper  20  is forced out of the seat  42 , by passing over the leading edge  42   a  thereof. Once the keeper  20  clears the leading edge  42   a  of the seat  42 , the compression springs  32  force the return of the keeper toward its locking position, and the door takes its intermediate position. As the closing of the door continues, it freely passes in the clearance area  15  to its closed position. 
     Reference is now made to  FIG. 7A-C  are corresponding to  FIG. 1-3  above, illustrating another example of a retention mechanism  111  which has a similar principle of operation to the retention mechanism  11 , with a slight structural modification in its biasing mechanism. The retention mechanism  111  comprises a plunger mechanism  126  configured to bear against a keeper  120 , and two plunging rods  130  connected to a biasing plate  128 , and having compression springs  132  disposed thereon between the biasing plate  128  and a housing  122 . 
     The housing  122  is formed with two through-going apertures  134  sized so as to allow passage therethrough of the plunging rods  130 , while preventing passage therethrough of the compression springs  132 , so that the springs bear between the biasing plate  128  and the housing  122  when compressed, causing the biasing plate  128  to bias the keeper  120  toward the locking position. 
     One of the advantages of the above described clearance area lies in situations (e.g., emergency situations) when there is a need for an outside or an inside operator to open the door, at least to a slight angle. It should be appreciated that for such an operator is can be much easier to manipulate the door to this slight angle (e.g., the first angle α), if the retention mechanism does not resist to the opening of the door until the door reaches the slight angle. In order to allow this, the presently disclosed retention mechanism provides a clearance area, through which the door can be easily pass without resistance from the retention mechanism. 
     In additional, it is appreciated the less resistance there is for opening or closing a door (when its latch is located at the clearance area), the less time is needed for receiving the needed position of the door (e.g., the intermediate position). This saving of time may have an importance in different critical conditions in which time is important and should be saved. 
     Those skilled in the art to which this invention pertains will readily appreciate that numerous changes, variations and modifications can be made without departing from the scope of the invention mutatis mutandis.