Abstract:
A child safety seat is disclosed which is incorporated into the squab of a vehicle seat in which part of the squab can be moved to an elevated position. The child safety seat incorporates at least one latch to maintain two components of the seat in a predetermined relative position. One of those components carries the latch and the other component carries a latch pin configured to co-operate with the latch. The latch defines a channel between two side walls, the side walls being provided with recesses. The channel contains a pivotally-mounted latch element which defines a recess. The latch element is movable pivotally between a first position in which the recess therein defines a mount accessible by the latch pin to enable the latch pin to be inserted into the recess in the latch element and being movable to a retaining position in which the latch pin, retained in the recess in the latch element, is retained in the recesses formed in the side walls of the channel. A releasable mechanism is provided to retain the latch element in its retaining position.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
   This application claims priority to GB 0310630.9 filed May 8, 2003 which is currently pending. 
   BACKGROUND OF THE INVENTION 
   The present invention relates to a child safety seat. It has been proposed previously to provide a child safety seat for use in a motor vehicle, the child safety seat incorporating a squab which is initially an element forming part of the main squab or the back rest of the seat. The squab of the child seat is moveable upwardly from an initial position, in which the back seat of the vehicle may be used by an adult, to an operative position, in which the back seat of the vehicle is prepared for use by a child. 
   A safety seat of this type is disclosed in GB-A-2368272. 
   It is most desirable that whenever the squab of the child is in a predetermined position, either the lowered inoperative position or the raised operative position, the squab should be retained in that position in such a way that it cannot inadvertently move to the other position, even if an accident should occur. 
   The present invention seeks to provide an improved child safety seat. 
   According to the present invention, there is provided a child safety seat, the child safety seat being incorporated in the squab of the vehicle seat and having a part of the squab which can move to an elevated position, the child safety seat incorporating at least one latch to maintain two components of a seat in a predetermined relative position, one component carrying the latch and the other component carrying a latch pin to co-operate with the latch, the latch defining a channel between two side walls, the side walls being provided with recesses therein, the channel containing a pivotally mounted latch element, the latch element defining a recess therein, the latch element being moveable pivotally between a first position in which the recess therein defines a mount accessible, by the latch pin, to enable the latch pin to be inserted into the recess in the latch element and being moveable to a retaining position in which the latch pin, still retained in the recess in the latch element, is retained in the recesses formed in the side walls of the channel, a releasable mechanism being provided to retain the latch element in the retaining position, the release mechanism incorporates a plunger moveable against a resilient bias traversely of the axis of the channel, the plunger being positioned to engage part of the latch element to prevent rotation of the latch element from the retaining position to the release position. 
   Advantageously, the plunger is operable by means of a Bowden cable. 
   Conveniently, the child safety seat is provided with two said latches. 
   In order that the invention may be more readily understood, and so that further features thereof may be appreciated, the invention will now be described, by way of example, with reference to the accompanying drawings in which: 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a diagrammatic side view of part of a rear seat of a motor vehicle provided with an integrated child&#39;s safety seat in accordance with the invention, showing the seat in one condition with the child safety seat stowed, 
       FIG. 2  is a view corresponding to  FIG. 1  showing the child safety seat in the operative condition, 
       FIG. 3  is an enlarged view of part of the seat as shown in  FIG. 2 , 
       FIG. 4  is a view corresponding to  FIG. 3  showing that part of the seat in an alternative condition, 
       FIG. 5  is an exploded view of the latch as shown in  FIGS. 3 and 4 , 
       FIG. 6  is a partially broken away view of the latch of  FIG. 5  in the release position, and 
       FIG. 7  is a view of the catch in the retaining position. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring initially to  FIG. 1  of the accompanying drawings a vehicle seat  1  is provided, the seat having a squab structure  2  and a backrest  3 , the seat being associated with a conventional safety belt  4  which is of the lap-and-diagonal form. 
   The squab section  2  of the seat is divided into two regions, a fixed rear region  5  and a moveable front region  6 . The front region  6 , as will become clear from the following description, can be moved from a stowed position, as shown in  FIG. 1 , in which the rear region  5  and the front region  6  together form a conventional squab, to an operative condition, as shown in  FIG. 2 , in which the front region  6  forms the squab of a child seat. 
     FIG. 3  illustrates the structure of the front part  6  of the squab section  2  of the seat. 
   Referring to  FIG. 3  of the accompanying drawings, a mounting plate  10  is provided adapted to be secured to the frame underlying the squab section  2  of the seat. The mounting plate  10  is provided with two upwardly directed lugs  11  each of which supports, by means of a respective pivot pin  12 , an arcuate arm  13 . The arms  13  may pivot about the axis defined by the pivot pins  12 . Each arm  13  is of arcuate form and terminates with a further pivot pin  14 . The arm  13  is provided with a projecting latch pin  15  (see  FIG. 4 ) which co-operates with a latch, shown schematically as latch  16  provided on the mounting plate  10 . The latch  16  may be actuated by means of a Bowden cable  17 . The catch serves to retain the arcuate arm  13  in the operative position illustrated in  FIG. 3 . The latch will be described in greater detail below. 
   The pivot pin  14  supports a mounting tray  20 . The forward edge of the mounting tray  20  is pivotally mounted for pivotal movement about the axis defined by the pivot pins  14 . The mounting tray extends, in the position illustrated, generally rearwardly from the pivot pins  14  in a substantially horizontal direction. The mounting tray is located above the rear part  5  of the squab unit of the seat. 
   A locking detent  21  is provided at the forward edge of the tray  20  in the region of the pivot pin  14  for the purpose which will be described hereinafter. The main, horizontal extending portion of the mounting tray  20  is provided with aligned pairs of upstanding lugs  22 ,  23 . The first pair of aligned lugs  22 , located forwardly on the mounting tray  20 , are provided with aligned pivot pins  24  which support a first pair of linear links  25 , the upper ends of the links  25  being pivotally connected by pivots  26  to a child supporting squab  27  which actually constitutes a principal element of the front portion  6  of the squab  2  of the seat  1  as shown in  FIG. 1 . The upper surface of the child supporting squab is padded and upholstered. The linear links  25  as shown in  FIG. 3  are inclined slightly forwardly. A compression spring  28  is provided extending between the mounting tray  20  and the child supporting squab  27  in the region of the links  25 , the axis of the compression spring being inclined slightly rearwardly relative to the axis of the links  25 . 
   At least one of the links  25  is provided with a projecting finger or tab  29  which extends from the link and which is connected to a drive rod  30  which extends to a damper  31  which may, for example, be a hydraulic damper. The damper  31  is connected to the mounting tray  20  by means of a lug  32 . 
   The second pair of aligned lugs  23 , provided at the rear of the mounting tray are provided with aligned pivot pins  33 , which support a second pair of linear links  34 , the upper end of each linear link  34  being connected, by means of a pivot  35 , to a rear part of the child supporting squab  27 . The rear links  34  are inclined forwardly and thus parallel with the forward links  25 . A further compression spring  36  is provided extending between the mounting tray  20  and the child supporting squab  27  in alignment with the rear links  34 . The axis of the spring  36  is substantially parallel with the axis of the spring  28 . 
   The child support squab  27  is provided with a depending arm  37  carrying a projecting latch pin  38 . The latch pin is to be retained by a latch  39  mounted on the mounting tray  20  to secure the squab  27  to the tray  20 . The latch  39  will be described in greater detail below. 
   The child supporting squab  27  is provided with an actuating button  40  provided towards the forward edge of the child supporting squab  27 . The button  40  is adapted to actuate the Bowden cable  17  which releases the latch  16 . The button  40  can also be actuated to release a retainer which is adapted to engage the detent  21  provided on support tray  20 , as well as the latch  39  on the mounting tray  20 . 
   It is to be appreciated that the described child supporting squab  27  is illustrated in  FIG. 3  in the operative position. It is to be understood that if the actuating button  38  is actuated, the latch pin  15  may be released by the latch  16  and the entire child supporting squab may be pivoted forwardly, with the arcuate arms  13  pivoting about the pivot axis defined by the pivot pins  12  and with the child supporting squab pivoting about the pivot axis  14 . The arrangement may then occupy the position as shown in  FIG. 4 . It will be appreciated that with a slight further movement the illustrated components will be in such a position that the child supporting squab  27  again constitutes the front section  6  of the squab  2  of the seat. It has, of course, been known previously to provide a child supporting squab which can move pivotally, in this way, between an operative position and a stowed position, and vice versa. 
   In the described embodiment of the invention, the child supporting squab  27  is mounted on the support tray by means of a parallel arm linkage constituted by the arms  25  and  34 , and is biased upwardly by means of the compression springs  28  and  36 . When the arrangement is to be in the stowed condition shown in  FIG. 1  manual pressure is applied to the child supporting squab  27  thus compressing the springs  28  and  36  until a catch actuated by the button  40  engages the detent  21  provided on the support tray  20  and the latch pin  38  is retained in the catch  39  thus retaining the child supporting squab  27  in a predetermined position relative to the support tray  20 . However, when the child safety seat is to be used by a child, the components are moved to the position illustrating in  FIG. 3  and the catches operated by the button  40  are released so that the child supporting squab  27  is moved to an elevated position relative to the support tray  20  by the springs  28  and  36 . 
   In the foregoing description, reference has been made to two latches, latch  16  and latch  39  each of which is to engage and retain a co-operating latch pin in form, respectively, of latch pin  15  and the latch pin  38 . Each of the two catches, in this embodiment of the invention, are of identical design and thus only one latch in the form of latch  16 , will be described. The latch  16  comprises a support plate  41 . The support plate  41  has a base  42  and two upstanding side walls  43 ,  44  which are spaced apart to form an open topped channel. A “U” shaped recess  45  is formed in the upper part of the first side wall  43  and a corresponding “U” shaped recess  46  is provided in the second side wall  44  in alignment with the first recess  45 . A first aperture  47  is provided in the side wall  43  at a position adjacent the base of the “U” recess  45 . A corresponding aperture (not shown) is defined in the second side wall  44 , the two apertures being in alignment. 
   The first side wall  43  extends away from the “U” shaped recess  45  by a greater extent than does the side wall  44 . A further aperture  48  is provided in the portion of the side wall  43  which extends beyond the end of the side wall  44 . 
   A further opening is provided in the side wall  44  (not shown) for the purpose that will be described herein after this paragraph. A spring housing  49  is provided adapted and configured to be abut against the side wall  44 . The spring housing has an aperture  50  therein to be co-aligned with the aperture  47  is the first side wall  43  and the co-aligned aperture in the second side wall  44 . The interior of the housing  49  defines a cylindrical cavity  51  adjacent the aperture adapted to receive a torsion spring  52 . The torsion spring  52  has a first projecting end  53  adapted to engage part of the housing and a second projecting end  54  adapted to pass through the said opening in the side wall  44  into the space between the two side walls. 
   A pivot pin  55  is provided to pivotally support a latch element  56  within the channel. A latch element is in the form of a plate having an aperture  57  therein. The plate is configured to be inserted between the two upstanding side walls  43 ,  44  with the pivot pin  55  passing through the aperture  47 , through the aperture  57  formed in the latch element  56 , through aperture formed in the upstanding wall  44 , through the central part of the torsion spring  52 , and through the aperture  50  and in the spring housing  49 . The end  54  of the torsion spring  52  passes through the opening in the side wall  54  to engage a second aperture  58  formed in the latch plate  56 . To one side of the aperture  57  the latch plates define a “U” shaped slot or recess  59  and to the other side defines a projecting tongue  60 . 
   Connected to the spring housing  49  is a cylindrical plunger housing  61  which contains a plunger  62  which is biased by means of a spring  63  but which can be retraced by means of Bowden cable  64 . The plunger  62  is in alignment with the aperture  48  formed in the first side wall  43  and when extended engages the aperture  48 . 
   When the components are assembled, the latch element  56  may move pivotally, against a bias imparted thereto by the torsion spring  52  about an axis defined by the pivot pin  55 . The tongue  60  is in that part of the channel adjacent the aperture  48  and the “U” shaped recess  59  is in that part of the channel which defines the two identical “U” shaped recesses  45  and  46  as formed in the side walls  43  and  44 . 
     FIG. 6  shows the catch in the release position. The plunger  62  has been withdrawn and does not traverse the channel. Consequently the latch element is free to rotate, and it can be seen that the tongue  60  provided at the end of the latch element may move between the end of the plunger  62  and the aperture  48  formed in the upstanding side wall  43 . 
   The latch element is biased, by the spring  52 , to move in a clockwise direction as shown in  FIG. 6  so that the “U” shaped recess is elevated and presents an open mouth above the top of the “U” shaped recesses  45  and  46 . The mouth may receive the latch pin  15  which is shown in an initial position just above the latch  16 . 
   It is to be appreciated that as the latch pin  15  is inserted into the open mouth of the “U” shaped recess  59  in the latch element  56 , the latch element will rotate against the biased imparted by the spring, moving the pin downwardly. The pin enters the “U” shaped recesses  45  and  46 . As the latch plate continues to move, the tongue  60  moves out of the region between the end of the plunger  62  and the aperture  48  and under the bias imparted thereto by the spring  63 . The plunger moves across the channel, so that the end of the plunger becomes inserted in the aperture  48 , as can be seen in  FIG. 7 , the plunger thus extending under the tongue  60  and preventing movement of the latch element in the counter-clockwise direction. The latch pin  15  is thus securely trapped by the combination of the “U” shaped recesses in the channel defined by the upstanding walls  43  and  44  and the “U” shaped recess  59  formed in the latch  56 . Even if subjected to “G” forces, the latch will not be removed since the spring  63  is selected to be sufficiently strong as to resist movement of the plunger  62  due simply to acceleration forces applied to the plunger  62 . Indeed the plunger  62  may be made to have a very low mass. 
   When the latch is to be released, tension is applied to the Bowden cable  64 , thus withdrawing the plunger  62  against the resilient bias applied transversely of the axis of the channel by the spring  63 . As the plunger is moved to the retracted position shown in  FIG. 6 , the latch element  56  is again free to rotate, as the plunger no longer engages the tongue on the latch element, and the latch element can rotate to the position shown in  FIG. 6 , thus releasing the latch pin  15 . 
   The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof. 
   While the above description constitutes the preferred embodiment of the present invention, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope and fair meaning of the accompanying claims.