Abstract:
A child safety seat having a seat, a backrest, and a belt device for buckling a child therein. The belt device includes a shoulder belt routed through an opening in the backrest. The opening includes a longitudinal slot extending in a longitudinal direction of the backrest in a reclining element and a belt slot in a belt guide piece. The guide piece is movable along the reclining element to adapt the position of the belt slot to the child&#39;s body. The guide piece detachably connects to the reclining element via a locking device having a locking element pretensioned by a reset force. An actuating element on the reclining element applies tensile force to the tensioning element, counter to the reset force. This moves the locking element into a release setting, thus releasing the locking device and displacing the guide piece along the longitudinal direction of the backrest.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of EP 121 689 81, filed May 22, 2012. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Technical Field 
         [0003]    The invention relates to a child safety seat for vehicles. 
         [0004]    2. Background Information 
         [0005]    Such types of child safety seats are known from the prior art. They have a seat surface and a backrest connected to the seat surface for the child that is to be held in the child safety seat. Furthermore, they have devices for affixing the child safety seat to the vehicle seat. These devices may include, for example, retaining receptacles for the seatbelts in the vehicle if the corresponding child safety seat is to be affixed to the vehicle seat by means of said vehicle seatbelt or seatbelt system. There are also known child safety seats that may be connected to the vehicle seats or to the vehicle chassis, in the area of the vehicle seats, on their fastening systems&#39; retainer eyelets, as is done with the so-called ISOFIX system, for example. There are also child safety seats that can be connected directly to a vehicle seat or affixed to it in that initially a base is connected to the vehicle seat via the vehicle&#39;s seatbelt or the ISOFIX system or a comparable system, and the child safety seat is then connected to the base, for example through a latching system formed in the base and the actual child safety seat. 
         [0006]    Furthermore, such types of child safety seats have their own belt system for buckling up the child being held in the seat. Such types of belt devices have at least one shoulder belt, which is routed through an opening in the backrest and proceeds partially onto a backside of the backrest. The backrest can be subdivided into a reclining element and a belt guide piece that can be moved relatively with respect to this, wherein at least one longitudinal slot extending in the longitudinal direction of the backrest is disposed in the reclining element and one belt slot is disposed in the belt guide piece. Due to the extension of the belt guide piece in the longitudinal direction of the backrest, the height of the belt slot and thus the outlet height of the at least one shoulder belt, which is routed through the belt slot, out of the backrest on its front, is adjusted and thus the belt position is adapted to the body size of the child. 
         [0007]    Because a corresponding adjustment and adaptation of the position of the belt guide piece must take place such that once a position is adjusted, it is reliably maintained, a locking device is provided with such types of child safety seats, which has a locking element, which is pretensioned in a locking setting due to reset force, and which further has an actuating element for loosening the locking element from its locking setting and enabling an extension of the belt guide piece. With common child safety seats, all of these elements are fully contained on a backside of the reclining element. 
         [0008]    Corresponding common child safety seats are known, for example, from EP 2 066 526 B1 as well as from U.S. Pat. No. 6,030,047 and U.S. Pat. No. 6,491,348. 
         [0009]    With the child safety seats disclosed in the listed prior art, which involve seats for small children, which are seats of the so-called 0/0+ group or group 1, the mechanism for height adjustment of the seat-specific belt device is operated from the backside of the child safety seat, or more specifically from the backside of the backrest, wherein a respective actuating element on the back must be accessed, which means that the back of the child safety seat must be released and made accessible. 
         [0010]    EP 2 208 637 A1 discloses a further example of a child safety seat in which, however, not all of the elements of the locking device are disposed on the backside of the reclining element. Release levers are provided therein and routed to the front side of the reclining element and can be actuated from the front side of the child safety seat in order to adjust the height of the belt device, even on a child safety seat that is installed in the vehicle and whose backside is not accessible. Thus, in this case, height adjustment of the belt guide piece for adapting the belt device to the body size of the child, though different than with the aforementioned solutions, common and known from the prior art, is enabled even when the child safety seat is installed in the vehicle; however, the handles, as parts of the release levers, are not located on the backside of the reclining element, which is different than the commonly known prior art, but are instead located laterally all the way to the area in which the head of the child being held in the child safety seat rests; and, in an extreme case, this could cause inherent risk of injury during a side impact crash. In this regard, this most recently described solution according to EP 2 208 637 A1 must be considered disadvantageous and unfavorable. 
       SUMMARY 
       [0011]    The objective of the invention is thus to further develop a common prior art, as it is disclosed in EP 2 066 526 B1 and U.S. Pat. No. 6,030,047 as well as U.S. Pat. No. 6,491,348 to the extent that it is possible to release the locking device and thus extend the belt guide piece and adapt the belt device to the body size of the child being held in the child safety seat, in a simple and reliable manner, without the routing of elements of the locking device from the backside of the reclining element to other locations, even when the child safety seat is already installed in the vehicle and even when the child is already seated in the child safety seat. 
         [0012]    According to the invention, with a common child safety seat of the type described at the beginning, the actuating element is a tensioning element on the backside of the reclining element routed in the direction of its upper longitudinal end, wherein when tensile force is applied to the tensioning element, the locking element can be brought from the locked setting into the released setting against the reset force, in which it triggers a release of the locking device, thus enabling displacement of the belt guide piece in the longitudinal direction of the backrest. 
         [0013]    Such type of tensile element routed in the direction of the upper end of the reclining element can also be accessed even when the child safety seat is already on a vehicle seat in the vehicle and connected therein and even if a child is already being held in the seat; thus, said element can be used to disengage the locking device via tensile actuation in order to adjust to the correct height position of the belt guide piece and adapt the belt device to the body size of the child. Therefore, it is not necessary to detach the child safety seat from the vehicle seat in order to undertake a corresponding adjustment. Instead, the correct belt height adjustment can be carried out when the child has already taken up the required space in the child safety seat, which means that the belt height can be adjusted very precisely to the body size of the child, which, as a whole, will contribute to improved safety of the child in the seat. 
         [0014]    The tensioning element can be in any suitable form, for example in the form of a tensioning rod, a tensioning cord, or a tensioning chain. A flat textile strap or a textile belt is especially preferred in this case. Such type of strap or especially such type of belt is, on the one hand, flexible and does not cause any risk of injury even if it protrudes in an area on the upper end of the reclining element. On the other hand, such type of belt or such type of strap can also be designed to have sufficient tensile strength so that it is stable for a long period of time and over a large number of actuation cycles. 
         [0015]    The locking device comprises, as a locking element, one locking rod, guided through at least one longitudinal slot running transversally to a tangential plane of the backrest and formed in an extension of the belt guidance part rigidly connected to said backrest, at least two holding receptacles, formed in different longitudinal positions of the reclining element, for the positive-locking retaining of at least a section of the locking rod, and a guide carriage exhibiting a guide slot disposed on the belt guidance part and running, at least in sections, transversally to the tangential plane and also transversally to the longitudinal slot, which guide carriage can be displaced relative to said belt guidance part in the longitudinal direction of the backrest, then a correspondingly simply and reliable locking device that can be actuated with a tensile element can be created. 
         [0016]    Due to the interaction between the longitudinal slots, formed in the extensions, transverse to a tangential plane in the backrest, which slots particularly and primarily may run orthogonally with respect to said tangential plane, and the guide slot in the guide carriage, which runs both transversely with respect to the direction of extension for the longitudinal slot as well as transversely with respect to the tangential plane, the locking rod, which, in particular, may have a circular diameter, being routed through both the longitudinal slot as well as the guide slot when there is a corresponding movement of the guide carriage, upon a displacement of the guidance carriage can be moved outward, i.e. away from the backrest element, or, respectively, inward. i.e. back toward it, depending on the direction of said displacement in the longitudinal slot. This results in a lifting of the locking rod out of the at least one retaining receptacle, in which it is being held and rests in a locking setting with positive-locking, or in a lowering of the locking rod into such type of retaining receptacle for locking into a selected position. The movement conversion mechanics formed by the described method enables the transference of a tensile force directed essentially tangentially with respect to the backrest or a corresponding tensile movement in a transverse movement of the locking rod, directed, particularly for the most part, vertically thereto, from at least one retaining receptacle, in which it is resting in a locked position, or into such, wherein the reset force forces the locking rod into the retaining receptacle. In this process, the tensioning element can be, advantageously, directly connected to the guide carriage. 
         [0017]    In doing so, the guide slot can be curved, at least in one section. In this advantageous embodiment, the guide slot differs, particularly, from the longitudinal slot, which extends, particularly, in a straight line. Due to the curved progression of the guide slot, in this advantageous embodiment a resulting movement of the locking rod is obtained, wherein this movement can be adjusted through the type and progression of the curve in that the locking rod is initially released slowly and slightly from its locking setting and subsequently lifted with a quicker movement, with the steeper progression of the guide slot as compared to the tangential plane, when further removed from the backrest and from the locking setting. 
         [0018]    The guide carriage is preferably secured in a forcibly actuated manner to the belt guide piece according to a further advantageous embodiment. This prevents the guide carriage from falling or otherwise detaching from the belt guide piece. The enforced guidance determines the direction of motion for the guide carriage. 
         [0019]    Bedstops can advantageously be disposed to limit the lines of movement for the guide carriage against the belt guide piece. 
         [0020]    The guide slot is particularly designed in the guide carriage such that it extends from an upper end of the guide carriage facing toward the upper end of the backrest to a lower end of the guide carriage facing the lower end of the backrest, away from the backside of the backrest. This design and guidance of the guide carriage results in a forcibly actuated movement of the locking rod away from the reclining element when the guide carriage moves toward the upper end of the reclining element, particularly, when it is pulled by the tensioning element rigidly attached to the guide carriage. 
         [0021]    According to a further advantageous embodiment of the invention, a bearing bracket, permanently disposed on the belt guide piece, can be provided, as well as a spring element, disposed on the lower end of the guide carriage between said bearing bracket and a front surface, which spring element is used to apply the reset force to the locking element by pushing the guide carriage toward the upper end of the backrest, whereby the locking rod is forced, in a forcibly actuated manner, through the guide and the longitudinal slot toward the backside of the reclining element, into the at least one retaining receptacle, in the locking setting. The spring element may advantageously be a helical spring. 
         [0022]    The retaining receptacles into which the locking rod can extend, and in which it may be fixed in order to lock in a positive-locking manner, may be designed, particularly advantageously, with two retaining receptacle strips disposed on the backside of the reclining element said retaining receptacle strips are permanently connected to the reclining element and positioned opposite one another and essentially extend in a longitudinal direction of the backrest. Within these retaining receptacle strips, there is a plurality of retaining receptacles disposed and/or formed, of which respectively two are positioned correspondingly at the same longitudinal position, in order to allow for positive locking retaining of the locking rods at various positions along the longitudinal direction. A pair of retaining receptacles, disposed at the same longitudinal position and contained in one of the retaining receptacle strips each, then forms, as a whole, the retaining receptacle for the locking rod in a height and locking setting of the belt guide piece. 
         [0023]    According to a further advantageous embodiment of the invention, a headrest may be disposed at the belt guide piece on the front of the reclining element. This headrest is then moved simultaneously in the longitudinal direction of the backrest and its height is also adjusted and adapted to the body size of the child being held in the child safety seat when the height adjustment is being carried out for the belt guide piece. The headrest is moved to the position at which the head of the child is at rest when the child&#39;s body rests against the backrest in a relaxed state. This headrest advantageously has side pieces for securing the head of the child at the sides. These side pieces are intended to particularly absorb the lateral forces acting on the child&#39;s head in the event of a corresponding side impact or accident. The headrest can advantageously be connected, as a joint, to the belt guide piece around a rotational axis proceeding substantially in the transverse direction of the backrest. Such type of joint-like connection enables the headrest to be tipped over, for example to adapt to a curve in the backrest, as is frequently the case, particularly with child safety seats in group 0/0+. In particular, safety in the event of an accident is also improved, however, by such type of joint-like connection. This type of joint means specifically, in the event of an impact or through a back pulse of the child&#39;s head subsequent to this, the child&#39;s head may displace together with the headrest, and when the head subsequently moves backward, contact of the head to or in the headrest is significantly improved. This results, in particular, in extensive covering of the side pieces of the headrest with the child&#39;s head. 
         [0024]    The belt guide piece can advantageously be formed through a belt guide plate disposed on the backside of the reclining element, in which the belt guide slots, formed transversely with respect to the longitudinal slots, are appropriately disposed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0025]    Further advantages and features of the invention may be derived from the following description of an exemplary embodiment in reference to the enclosed figures. The following is shown: 
           [0026]      FIG. 1  shows a side view of an exemplary embodiment of a child safety seat according to the invention; 
           [0027]      FIG. 2  shows a top view of the child safety seat according to  FIG. 1  with the belt guide piece and the headrest set at the highest setting; 
           [0028]      FIG. 3  shows a perspective view of the child safety seat from the bottom rear in the position with the belt guide piece and the headrest at the highest setting; 
           [0029]      FIG. 3   a  shows an enlarged sectional representation of the locking device in the position shown in  FIG. 3 ; 
           [0030]      FIG. 4  shows a longitudinal section through the child safety seat with the combination of the belt guide piece and the headrest at the highest setting; 
           [0031]      FIG. 4   a  shows a sectional view of the locking device from  FIG. 4 ; 
           [0032]      FIG. 5  shows a top view of the child safety seat with the belt guide piece and the headrest in the lowest position; 
           [0033]      FIG. 6  shows a perspective view from the bottom rear of the child safety seat in the setting and positioning with the belt guide piece in the headrest in the lowest possible position according to  FIG. 5 ; 
           [0034]      FIG. 6   a  shows a sectional enlargement of the locking device from  FIG. 6 ; 
           [0035]      FIG. 7  shows a longitudinal representation of the child safety seat with the adjustment and position of the belt guide piece and the headrest according to  FIG. 5 ; 
           [0036]      FIG. 7   a  shows an enlarged sectional view of the locking device from  FIG. 7 ; 
           [0037]      FIG. 8  shows a perspective view from the bottom rear of the child safety seat with the belt guide piece in the headrest in the highest position and with the locking device released due to pulling on the actuating element; 
           [0038]      FIG. 8   a  shows an enlarged sectional view of the locking device from  FIG. 8 ; 
           [0039]      FIG. 9  shows a longitudinal section of the child safety seat with the belt guide piece and the headrest at the highest position and with the locking device placed in the release setting due to pulling on the actuating element; and 
           [0040]      FIG. 9   a  shows a sectional view of the locking device according to  FIG. 9 . 
       
    
    
     DETAILED DESCRIPTION 
       [0041]    The figures show a potential implementation of a child safety seat for vehicles according to the invention in various views and with various positions of the child safety seat  1  with its own belt device as well as its own locking device by means of an exemplary embodiment in the form of a child safety seat  1 , which is designed for secure and safe placement and transport of a small child in a vehicle and belonging to group 0/0+. Obviously, the invention can also be implemented with a child safety seat from another class, for example of group 1. 
         [0042]    The child safety seat  1  according to the exemplary embodiment has a seat surface  2  and a backrest  3  connected to said seat surface  2 . A belt hook  4  disposed on the backside of the backrest  3  as well as two belt retaining receptacles  5  disposed laterally adjacent to the seat surface  2  serve, in the customary and known manner, to hold the shoulder belt section in a threaded-in manner (in the belt hook  4 ) as well as the pelvis belt section (through the belt receivers  5 ) of a three-point belt located in the vehicle, in order to connect the child safety seat  1  onto a vehicle seat against the direction of travel, e.g. the front passenger&#39;s seat or a rear seat of the vehicle. 
         [0043]    The child safety seat  1  further has a belt device formed on same and disposed thereon, shoulder belts  6  formed as a type of suspender belts (only shown here in one section), as well as a belt buckle in the area of the seat surface  2 , which is not shown here. 
         [0044]    Two longitudinal slots  7  are formed in parallel in the backrest  3  and in the longitudinal direction of the backrest  3 . These longitudinal slots  7  are formed in a reclining element  8  which is rigidly connected to the seat surface  2 . A belt guide piece  9  is disposed on the surface opposite the front side of the backrest  3 , on which front side a child placed in the child safety seat  1  sits, and has belt slots  10  through which the shoulder belts  6  are routed from the back of the backrest  3  to the front. A headrest  11  is disposed, with a joint-like connection, at the guide belt piece  9 , which guide belt piece  9  being displaceable relative to the reclining element  8  and in the longitudinal direction of the backrest  3 . A carrying handle  13 , which can be swiveled about a swiveling axis  12 , is used to grasp and transport the child safety seat  1  in a known manner. 
         [0045]    A locking device  14  is formed on the back of the backrest  3 , by means of which the belt guide piece  9  can be adjusted in various possible positions with respect to the reclining piece  8  and can be fixedly locked in its position with respect to the latter. In doing so, the belt guide piece  9  comprises a cover plate  15  disposed entirely on the back of the backrest  3 , which covers the longitudinal slots  7 . 
         [0046]    In the enlarged representations of  FIGS. 3   a ,  4   a ,  6   a ,  7   a ,  8   a , and  9   a , the locking device  14  is shown in greater detail in various positions and various views. In this regard, as the locking device  14  is described in greater detail in the following, the aforementioned figures are referred to in particular. 
         [0047]    The locking device  14  has two opposing retaining receptacle strips  17 , which extend in the longitudinal direction of the backrest  3  and which are fixedly connected to the reclining element  8  and which, at corresponding longitudinal positions, each have retaining receptacle notches  16 . The locking device  14  further comprises a locking rod  18 , which has a circular diameter, the ends of which can be accommodated in a respective retaining receptacle notch  16  of each of the two retaining receptacle strips  17  in order to be locked against a longitudinal movement. The locking rod  18  is routed through longitudinal slots  20  formed with the extensions  19  fixedly connected to the cover plate  15  of the belt guide piece  9 , wherein the longitudinal slots  20  and the extensions  19  are dimensioned such that the locking rod  18  can be moved in the longitudinal slots  20  transverse to the plane of the backrest  3 , particularly, therefore, also transverse to the cover plate  15 , to the extent that it is completely lifted from the retaining receptacle notches  16  of the retaining receptacle strips  17  and thus enables a relative displacement of the belt guide piece  9  with respect to the reclining piece  8 . 
         [0048]    In a guide  21 , provided with stops for limiting movement that are not shown in more detail here, formed at the cover plate  15  of the belt guide piece  9  and fixedly connected with said piece, a guide carriage  22  is disposed, which can be moved relative to said guide  21  and thus to the belt guide piece  9  in the longitudinal direction of the backrest  3 . 
         [0049]    In this exemplary embodiment, the guide carriage  22  has two legs  22   a,  each of which has a guide slot  23 . The locking rod  18  runs through these guide slots  23 , wherein the guide slots  23  have a progression that, in any case, in a section of which proceeds transversely with respect to the longitudinal extension of the longitudinal slots  19 , as well as transversely with respect to the tangential plane of the backrest  3 , by that also transversely with respect to the plane of the cover plate  15 . In particular, the progression of the guide slots  23  is curved. 
         [0050]    By means of a helical spring  25  placed between the guide carriage  22  and a counter bearing  24  fixedly connected with the cover plate  15 , the guide carriage  22  is forced into a position maximally displaced in the direction of the seat surface  2  relative to the cover plate  15  and thus relative to the belt guide piece  9 . 
         [0051]    As can be seen from a representation that is only shown in sections, the shoulder belts  6  run on the back of the backrest  3  over the locking rod  18  onward and are looped around said rod. 
         [0052]    A tensioning belt  26  is connected to the guide carriage  22 . Said tensioning belt  26  is threaded through the headrest  11  with a free end opposite the end connected to the guide carriage  22 , and protrudes out over the backside of this element. 
         [0053]    By pulling on the tensioning belt  26 , the guide carriage  22  is moved, against the spring force of the helical spring  25  relative to the belt guide piece  9 , more precisely to the corresponding cover plate disposed on, and belonging to, the belt guide piece, in the direction of the upper end of the backrest  3 . As a result, the locking rod  18  is forcibly actuated outward in the longitudinal slots  20  and out of the retaining receptacle notches  16  of the retaining receptacle strips  17 , forced by guidance of the guide carriage acting towards the lower end of the guide carriage  22  pointing toward the seat surface  2 , away from the backside of the backrest  3  as well as transversally to the plane of the backrest  3 . The belt guide piece  9  can then be moved relative to the reclining piece  8  in the longitudinal direction of the back, e.g. from the uppermost position shown in  FIGS. 2 to 4   a  toward a bottommost position shown in  FIGS. 5 to 7   a  or vice versa. Obviously, the belt guide piece  9  can also be locked in any of the potential intermediate positions in between, which are predetermined through the retaining receptacle notches formed at the various longitudinal positions of the retaining receptacle strips  17 . If the tensioning belt  26  is released, the force of the helical spring  25  forces the guide carriage  22  back into its base position displaced into the direction toward the seat surface  2  in which the guide slot  23  follows a course close lying to the backrest, such that the locking rod  18  is forced in the direction toward the backrest  3  and pushed into suitable retaining receptacle notches  16  in the retaining receptacle strips  17  and is held there in the corresponding locking setting. 
         [0054]    Due to the fact that, on the front of the backrest  3 , the headrest  11  is attached to the belt guide piece  9  such that it cannot be displaced in the longitudinal direction of the backrest  3  (only being able to swivel in a direction parallel to the extension of the locking rod  18 , i.e. transverse to the longitudinal direction of the backrest  3 , together with adjusting the correct position of the belt guide piece  9 , and thus adjusting the corresponding distance of the belt slot  10 , and thus the outlet position of the shoulder belt  6 , to the seat surface  2  for a corresponding adaptation to the body size of the child to be accommodated in the child safety seat  1  the headrest  11  is also adjusted. 
         [0055]    The great advantage of the embodiment according to the invention exists in that the tensioning belt  26  is easy to reach even when the child safety seat  1  is already installed and permanently positioned in the vehicle, and a child has already been placed in the child safety seat  1 , and that, the blocking device  15  can be adjusted with said belt in order to correctly adjust the position of the belt slots  10 , and thus the distance of the passage of the shoulder belts  6  through the backrest  3  to the seat surface  2 , and that this can be done with a few simple manipulations by hand. If the distance needs to be increased, with a simultaneous pulling on the tensioning belt  26  to release the locking device  15 , a movement of the belt guide piece  9  and the associated headrest  11 , toward the upper end of the backrest can also be carried out, e.g. in order to move the headrest  11  out of the lower positions shown in  FIGS. 5 to 7   a  into an upper position shown in  FIGS. 3 to 4   a , or any intermediate position. 
         [0056]      FIGS. 8 to 9   a  once again show the situation in which the guide carriage  22  is moved toward the upper end of the backrest  3  relative to the belt guide piece  9  and the cover plate  15  disposed thereon by applying tensile force to the tensioning belt  26  such that, due to the enforced guidance formed from the guide slots  23  and the longitudinal slots  20 , the locking rod  18  is lifted up from the retaining receptacle strips  17  to the extent that it is moved up over the retaining receptacle notches  16  and the belt guide piece  9  is released relative to the reclining piece  8 . 
       Reference List  
       [0000]    
       
           1  Child safety seat 
           2  Seat surface 
           3  Backrest 
           4  Belt hook 
           5  Belt retaining receptacle 
           6  Shoulder belt 
           7  Longitudinal slot 
           8  Reclining element 
           9  Belt guide piece 
           10  Belt slot 
           11  Headrest 
           12  Swiveling axis 
           13  Carrying handle 
           14  Locking device 
           15  Cover plate 
           16  Retaining receptacle notch 
           17  Retaining receptacle strip 
           18  Locking rod 
           19  Extension 
           20  Longitudinal slot 
           21  Guide 
           22  Guide carriage 
           22   a  Leg 
           23  Guide slot 
           24  Counter bearing 
           25  Helical spring 
           26  Tensioning belt