Patent Publication Number: US-2002008377-A1

Title: Height adjustment means for safety belt deflector fittings of vehicles

Description:
TECHNICAL FIELD  
       [0001] The invention concerns a height aduster for return fixtures of vehicle safety belts according to the preamble of claim 1.  
       STATE OF THE ART  
       [0002] Height adjusters of this kind are known in a variety of embodiments. In general this consists of the arresting mechanism with the latching lugs formed on the adjusting part which can engage in a form-locking manner in the latch openings of the guide rail. To release, the adjusting part is pressed towards the inside of the guide rail, i.e. as a rule over a support edge. The opposite movement then results in the renewed latching in. These movements require a considerable exposed space between the underside of the adjusting part and the topside of the B or C pillars of the vehicle against which rest the legs of the guide rail when fitted. This exposed space with its possibility for movement for the adjusting part has shown itself to be danger zone in the event of a side-on impact, as this can lead to the unintended release of the adjusting part and the latching into the lowest end position, causing the intended holding and safety function to be lost. Of significance in this case also is the fact that the entire adjusting part has a considerable mass (for example in the region of  70   g ) which is subjected to the acceleration. In connection with the existing exposed space it is possible therefore in unfavourable situations for the known systems or embodiments to unlatch. In this respect the known height adjusters lag behind the constantly rising safety requirements.  
       STATEMENT OF THE INVENTION  
       [0003] This is where the invention starts. It would like to develop a height adjuster of the type mentioned in such a way that it retains the selected latching position even in the event of a side-on collision.  
       [0004] This aim is achieved by means of the features of claim 1. Advantageous further developments are disclosed in the sub-claims.  
       [0005] As can be seen, the actual adjusting part can be so limited in its movement that it can only be displaced longitudinally. A dangerous exposed space, as is required for making a swivel movement required for latching in and out, is thus already avoided. Instead, only a small and light-weight part, which is picked up by the adjusting part in the longitudinal direction, is to be given an additional movement, namely perpendicular to the direction of movement of the adjusting part. This allows the blocking part for arresting to engage in the latch openings and also to be released from these again, wherein now—different as in the case of a swivel movement over a supporting edge—it covers only a short distances, namely in the range of the depth of the latch openings, which equals the material thickness of the guide rail. Less of a risk too is the substantially lighter mass (below 10 g) of the blocking part, movable alone more for the purpose of arresting.  
       [0006] As a result, in the event of a side-on crash there is provided a high degree of blocking safety, and this with a more simple construction. Further advantageous embodiments regarding safety are contained in the sub-claims. With the additional features it is also possible to improve the slideability, to reduce noise and to produce convenient assembly units (modules), as well as to counter any other dangers, especially serious injuries in the case of a head impact. 
     
    
    
     SHORT DESCRIPTION OF THE DRAWING  
     [0007] Further details and advantages are described in the following with the aid of the drawing for a preferred embodiment. These show:  
     [0008]FIG. 1 an exploded view of the individual parts of a height adjuster shown in perspective view,  
     [0009]FIG. 2 a plan view of an assembled height adjuster,  
     [0010]FIG. 3 the height adjuster of FIG. 2 in longitudinal section along line III-III,  
     [0011]FIG. 4 a  simplified the height adjuster of FIG. 3 in section along line IV-IV, in the arresting position,  
     [0012]FIG. 4 b  the same object in the displacement position,  
     [0013]FIG. 5 an exploded view of the individual parts of a different height adjuster shown in perspective,  
     [0014]FIG. 6 the assembled height adjuster of FIG. 5, also shown in perspective,  
     [0015]FIG. 7 the height adjuster of FIG. 6 in longitudinal section,  
     [0016]FIG. 8 a plan view of the height adjuster of FIG. 6,  
     [0017]FIG. 9 a  simplified the height adjuster of FIG. 6 at the level of its blocking part in cross-section, in the arresting position,  
     [0018]FIG. 9 b  the same object in displacement position and  
     [0019]FIG. 10 simplified the height adjuster of FIG. 6 at the level of its latching pins in cross-section, in the latching position. 
    
    
     [0020] According to FIG. 1 a height adjuster for the return fixture of a safety belt initially consists of a U-shaped guide rail  1  (in cross-section) with a central region  2  and arms  3  projecting away from the same at right angles. For securing this to (a B or C pillar of a vehicle) the guide rail  1  has an angled end piece  4  containing a drilling. In the central region  2  it furthermore has an elongated recess  5  as well as latch openings  5   a  arranged in pairs thereto.  
     [0021] With the guide rail  1  cooperate the following further parts: an adjusting part  6 , a blocking part  7 , a plastics cage  8 , which are all to be arranged inside, as well as a locking plate  9  and a plastics slider  10 , which are to be arranged on the outside. The adjusting part  6  has raised edges  6   a , especially in the longitudinal direction. These are partly perforated, simultaneously forming a guide  11  and a support for the blocking part  7 . The adjusting part  6  also carries a threaded bush  12  for a return fixture (not shown). The blocking part  7  in this case is constructed basically as a U-shaped bracket  7   a  whose arm is further bent in U-shape in the opposite sense. The exposed arms or ends  7   b  represent latching lugs which are fitted with their front ends  7   c  in the guide  11  of the adjusting part  6 .  
     [0022] The adjusting part  6  together with the blocking part  7  can be inserted in the plastics cage  8  which has latching lugs  13  on its narrow sides and slide springs  14 ,  15  on its longitudinal sides. The exposed ends  14   a ,  15   a  of the slide springs  14 ,  15  point in opposite directions. A bearing  16  for an adjusting lever is additionally formed on one narrow side.  
     [0023] Holding and closing the plastics cage  8  is served by the locking plate  9  which is to be fitted externally to the guide rail  1  and matches the shape of the guide rail  1 , i.e. the locking plate  9  has lateral regions which brush over the latch openings  5   a , and a central region which is lowered into the elongated recess  5  of the guide rail  1 . In the latter are located recesses  17  for the latching lugs  13  of the plastics cage  8  for forming a releasable clip connection.  
     [0024] The locking plate  9  also has a pair of latch openings  9   a  which, in the arresting position, mate with a pair of latch openings  5   a  of the guide rail  1  and can additionally receive the ends  7   b  of the blocking part  7  (see FIGS. 4 a, b ). Also provided is a corresponding recess for the blocking part  7  as well as the threaded bush  12 .  
     [0025] The plastics slider  10  finally has a similar form (together with recesses) as the locking plate  9 . In contrast to this, it is slightly shorter and has moulded-on slide springs  18  which are active between the lateral regions of the locking plate  9  and the central region  2  of the guide rail  1 . Furthermore, in the region of the recess for the blocking part  7  there is provided a channel section  19  for the better guidance of the blocking part  7 . When locking plate  9  and plastics cage  8  are clipped together, the plastics slider  10  is readily held in-between, just as the other movable parts are securely held and supported. An assembly unit or a function module is formed so to speak.  
     [0026] The FIGS. 2 and 3 show the assembled height adjuster which in this case is even provided for completeness with an operating lever, i.e. release or adjusting lever  20 . By means of this lever  20  it is possible to apply pressure from outside on the blocking part  7  so as to release this from its arresting position. The arresting position is illustrated in FIG. 4 a , the displacement position in FIG. 4 b . The relevant movement directions for the adjusting part  6  is illustrated by arrow  21  and for the blocking part  7  by the arrow  22 . The arresting position shown in FIG. 4 a  is retained by an elastic member, in this case a spring  23  is wedged between adjusting part  6  and blocking part  7 .  
     [0027] The FIGS.  5 - 10  show another height adjuster partly with modified features, partly with additional features. It comprises a guide rail  1 ′ with fastening hook  1 ′ a  for securing to the so-called B pillar of vehicles. A recess  5  is thus delimited in the longitudinal direction by guide surfaces  1 ′ b . The base of the adjusting part  6 ′ is provided with an opening for receiving a threaded bush  12 ′ which in this case is constructed as a loose lock nut. In the adjusting part  6 ′ can be inserted for movement a blocking part  7 ′. For simpler unlocking the arms  7 ′ b  of this are slightly bevelled. Otherwise a pressure spring  23  in turn ensures that the blocking part  7 ′ is moved into the arresting position.  
     [0028] The adjusting part  6 ′ can be inserted in a plastics cage or carriage  8 ′ which has slightly arc-shaped slide springs or slide sections  18 ′ which in the assembled state brush over its underside. On the topside of the guide rail  1 ′ is then located an upper part  9 ′ which is locked together with the carriage  8 ′, i.e. clipped together. Both the carriage  8 ′ as well as the upper part  9 ′ are made of plastics and ensures a light-weight and noise-exposed run of the adjusting part  6 ′ along the metal guide rail  1 ′. This even more so since on the upper part  9 ′ there are provided special guide ribs  9 ′ b  which cooperate with the guide surfaces  1 ′ b  of the guide rail  1 ′.  
     [0029] The upper part  9 ′ has a bearing  16 ′ for a lever  20 ′ which through a rotary point  20 ′ a , lugs  20 ′ b  and a working axis  20 ′ c  effects unlocking, i.e. for acting on (pressing) on the blocking part  7 ′ situated beneath this. As a special feature, each lever  20 ′ also has projections  20 ′ d  which are designed to if possible neutralise the forces which in the event of a crash act on the lugs  20 ′ b  and in an undesirable manner could release the blocking part  7 ′. The provision is made therefore that the projections  20 ′ d  are provided with so much mass that they can produce an effective counter moment effective on the other side of the rotary point  20 ′ a.    
     [0030] As an additional characteristic feature the adjusting part  6 ′ also has an additional chamber which in this case is constructed as an independent element  6 ″ and can be connected to the adjusting part  6 ′. In the adjusting part chamber  6 ″ transverse to the displacement direction is provided a continuous channel in which a spring element  24 ′ is insertable at both ends together with pin or roller-shaped latch elements  25 ′. The latch elements  25 ′ engage in groove-like impressions  26 ′ on the inside of the arms  3 ′ of the guide rail  1 ′ which are so arranged that a pre-latching can take place in a possible arresting position. The adjusting part chamber  6 ″ is arranged or to be arranged beneath the guide rail  1 ′ and can be joined to a complimentary part  9 ″, serving as a guide, above the guide rail  1 ′.  
     [0031] The height adjuster according to the invention is characterised by a high degree of operational safety. It slides well for adjusting and does not rattle. As a result of being made up of different parts, which are connected to each other essentially releasable, good preconditions exist also for other extreme situations, especially in the event of a head impact. The connecting points in this case act like preset breaking points and partly absorb the impact energy, thus reducing the danger of injury.  
     [0032] List of reference symbols  
     [0033] 1 ,  1 ′ guide rail  
     [0034] 1 ′ a  fastening hook  
     [0035] 1 ′ b  guide surface  
     [0036] 2  central region  
     [0037] 3 ,  3 ′ arm  
     [0038] 4  end piece  
     [0039] 5  recess  
     [0040] 5   a  latch opening  
     [0041] 6 ,  6 ′ adjusting part  
     [0042] 6 ″ (adjusting part) chamber  
     [0043] 6   a  edge  
     [0044] 7 ,  7 ′ blocking part  
     [0045] 7   a  bracket  
     [0046] 7   b ,  7 ′ b  arm, end  
     [0047] 7   c  front end  
     [0048] 8 ,  8 ′ plastics cage, carriage  
     [0049] 9 ,  9 ′ (locking) plate, upper part  
     [0050] 9 ″ complementary part for the chamber  6 ″ 
     [0051] 9   a  latch opening  
     [0052] 9 ′ b  guide rib  
     [0053] 10  plastics slider  
     [0054] 11  guide  
     [0055] 12 ,  12 ′ threaded bush  
     [0056] 13  latching lug  
     [0057] 14  slide spring  
     [0058] 14   a  exposed end  
     [0059] 15  slide spring  
     [0060] 15   a  exposed end  
     [0061] 16 ,  16 ′ bearing  
     [0062] 17  recess  
     [0063] 18  slide spring  
     [0064] 18 ′ slide section  
     [0065] 19  channel section  
     [0066] 20 ,  20 ′ (adjusting) lever  
     [0067] 20 ′ a  rotary point  
     [0068] 20 ′ b  lug  
     [0069] 20 ′ c  working axis  
     [0070] 20 ′ d  projection  
     [0071] 21  arrow  1   
     [0072] 22  arrow  1   
     [0073] 23  pressure spring  
     [0074] 24 ′ spring element  
     [0075] 25 ′ latch element  
     [0076] 26 ′ impression