Safety belt apparatus for vehicles

Abstract

The invention relates to a safety belt apparatus for vehicles, in particular motor vehicles having at least one safety belt ( 11 ), which is wound to a greater or lesser degree onto a belt reel ( 13 ) rotatably secured on the vehicle chassis ( 14 ) about an axis of rotation ( 12 ) and preferably biased by a spring retraction mechanism, in particular a spiral spring ( 15 ) in the belt winding up direction and/or having a belt draw out- blocking mechanism ( 26, 38; 55, 56, 57 ), which, with an attempted rapid draw out of the safety belt ( 11 ) and/or with in particular accident dependent accelerations and/or deviations of the vehicle position from the normal, horizontal arrangement of the vehicle blocks a further draw out of the safety belt ( 11 ), with a toothed ratchet wheel ( 29 ) being rotationally coupled to the belt reel ( 13 ) and cooperating with a blocking pawl ( 17 ) secured to the housing and movable into an out of engagement, in such a way that with the blocking pawl ( 17 ) moved into engagement with the toothed ratchet wheel ( 29 ), a rolling up movement of the belt reel ( 13 ) by the spring retraction mechanism ( 15 ) is possible, but not a pulling out of the safety belt ( 11 ), and wherein the blocking pawl ( 17 ) is movable into and out of engagement with respect to the toothed ratchet wheel ( 29 ) by a cam ring ( 18 ) concentric to the belt reel axis ( 12 ) via a step down transmission ( 20, 21, 27, 28 ) so that the blocking pawl ( 17 ) is moved out of engagement with a safety belt ( 11 ) which is drawn in to a greater or lesser degree and preferably at least fully drawn in and is movable into engagement with a further drawn out safety belt ( 11 ), preferably with a largely fully drawn out safety belt ( 11 ), wherein a toothed control wheel ( 21 ) is connected to the belt reel ( 13 ) via an eccentric transmission ( 27, 28 ) and has at its periphery a preferably wavelike arrangement of teeth ( 40 ), which is surrounded by an inner toothed ring ( 20 ) fixed to the housing of larger diameter and with complementary teeth ( 41 ), but with a smaller or preferably larger number of teeth, such that the toothed control wheel ( 21 ) stands in meshing arrangement with the inner toothed ring ( 20 ) over a restricted peripheral region and diametrically opposite thereto the two arrangements of teeth ( 40, 41 ) have a radial spacing such that the toothed control wheel ( 21 ) rolls off on the inner toothed ring ( 20 ) on rotation of the belt reel ( 13 ), and wherein the total draw out length of the safety belt ( 11 ) corresponds to an angle of rotation of the toothed control wheel ( 21 ) relative to the axis of rotation ( 12 ) of less than 360° and in particular of substantially 180°. The invention lies in the arrangement by which the toothed control wheel ( 21 ) is rotationally fixedly connected to the cam ring ( 18 ), but radially displaceable in the context of its eccentric movement, with the cam ring ( 18 ) having switching means ( 46, 47 ) along a first angular region ( 45 ) for the engagement and disengagement of the blocking pawl ( 17 ), and at least one switching element ( 49 ) along a second angular region ( 48 ) for at least one further belt draw out dependent switching operation.

1 . Safety belt apparatus for vehicles, in particular motor vehicles having at least one safety belt ( 11 ), which is wound to a greater or lesser degree onto a belt reel ( 13 ) rotatably secured on the vehicle chassis ( 14 ) about an axis of rotation ( 12 ) and preferably biased by a spring retraction mechanism, in particular a spiral spring ( 15 ) in the belt winding up direction and/or having a belt draw out blocking mechanism ( 26 ,  38 ;  55 ,  56 ,  57 ) which, with an attempted rapid draw out of the safety belt ( 11 ) and/or with in particular accident dependent accelerations and/or deviations of the vehicle position from the normal, horizontal arrangement of the vehicle, blocks a further draw out of the safety belt ( 11 ), with a toothed ratchet wheel ( 29 ) being rotationally coupled to the belt reel ( 13 ), preferably with a small rotary clearance and cooperating with a blocking pawl ( 17 ) secured to the housing and movable into an out of engagement, in such a way that with the blocking pawl ( 17 ) moved into engagement with the toothed ratchet wheel ( 29 ), a rolling up movement of the belt reel ( 13 ) by the spring retraction mechanism ( 15 ) is possible, but not a pulling out of the safety belt ( 11 ), and wherein, when the blocking pawl ( 17 ) is located in engagement with the toothed ratchet wheel ( 29 ), the toothed ratchet wheel is preferably rotatable against a spring force relative to the belt reel ( 13 ) within the rotary clearance and can bring a control pawl ( 61 ) attached to the belt reel ( 13 ) into engagement with a toothed ring ( 65 ) fixed to the housing, with the blocking pawl ( 17 ) being movable into and out of engagement with respect to the toothed ratchet wheel ( 29 ) by a cam ring ( 18 ) concentric to the belt reel axis ( 12 ) via a step down transmission ( 20 ,  21 ,  27 ,  28 ) so that the blocking pawl ( 17 ) is moved out of engagement with a safety belt ( 11 ) which is drawn in to a greater or lesser degree and preferably at least fully drawn in and is movable into engagement with a further drawn out safety belt ( 11 ), preferably with a largely fully drawn out safety belt ( 11 ), wherein a toothed control wheel ( 21 ) is connected to the belt reel ( 13 ) via an eccentric transmission ( 27 ,  28 ) and has at its periphery a preferably wave-like arrangement of teeth ( 40 ), which is surrounded by an inner toothed ring ( 20 ) fixed to the housing of larger diameter and with complementary teeth ( 41 ), but with a smaller or preferably larger number of teeth, such that the toothed control wheel ( 21 ) stands in meshing arrangement with the inner toothed ring ( 20 ) over a restricted peripheral region and the two arrangements of teeth ( 40 ,  41 ) have a radial spacing diametrically opposite thereto such that the toothed control wheel ( 21 ) rolls off on the inner toothed ring ( 20 ) on rotation of the belt reel ( 13 ), and wherein the total draw outlength of the safety belt ( 11 ) corresponds to an angle of rotation of the toothed control wheel ( 21 ) relative to the axis of rotation ( 12 ) of less than 360° and in particular of substantially 180°, 
 characterized in that 
 the toothed control wheel ( 21 ) is rotationally fixedly connected to the cam ring ( 18 ), but radially displaceable in the context of its eccentric movement, with the cam ring ( 18 ) having switching means ( 46 ,  47 ) along a first angular region ( 45 ) for the engagement and disengagement of the blocking pawl ( 17 ), and at least one switching element ( 49 ) along a second angular region ( 48 ) for at least one further belt draw outdependent switching operation.  
 
 
     
     
         2 . Safety belt apparatus in accordance with  claim 1 , 
 characterized in that 
 the switching element is a switching cam track ( 49 ) and actuates a micro-switch ( 50 ) fixed relative to the housing for the activation of a belt tensioner ( 35 ) after a predetermined draw outlength of the safety belt ( 11 ) from the fully drawn in state.  
   
     
     
         3 . Safety belt apparatus in accordance with  claim 1  or  2 , 
 characterized in that 
 the cam ring ( 18 ) has a part right cylindrical circumferential surface ( 51 ) along the first angular region ( 45 ) at the ends of which in the peripheral direction preferably radially outwardly projecting abutment steps ( 46 ,  47 ) are provided; which cooperate with a switching arm ( 52 ) of a rocker element ( 53 ) acting on the blocking pawl with two over-dead center positions such that the one abutment step ( 46 ), on striking the switching arm ( 52 ), pivots the rocker element ( 53 ) into the position which brings the blocking pawl ( 17 ) into engagement with the toothed ratchet wheel ( 29 ), and the other abutment step ( 47 ), on striking the switching arm ( 52 ), pivots the rocker element ( 53 ) into the position which brings the blocking pawl ( 17 ) out of engagement with the toothed ratchet wheel ( 29 ).  
 
 
     
     
         4 . Safety belt apparatus in accordance with  claim 3 , 
 characterized in that 
 the abutment step which becomes active during the drawing inof the belt strikes against the switching arm ( 52 ) of the rocker element ( 53 ) when the safety belt ( 11 ) is not fully drawn in, and in that the switching arm ( 52 ) subsequently lies adjacent or against a preferably part right cylindrical peripheral surface ( 54 ) with a radius greater by the height of the abutment step ( 47 ).  
   
     
     
         5 . Safety belt apparatus in accordance with  claim 3  or  4 , 
 characterized in that 
 the abutment steps ( 46 ,  47 ) have an angular spacing of 120° to 160°, preferably 130° to 150°, and in particular of about 140°.  
 
 
     
     
         6 . Safety belt apparatus in accordance with one of the preceding claims, 
 characterized in that 
 the first angular range ( 45 ) amounts to 180° to 220°, preferably 190° to 210°, and in particular to about 200°.  
   
     
     
         7 . Safety belt apparatus in accordance with one of the preceding claims, 
 characterized in that 
 the second angular range ( 48 ) amounts to 140° to 180°, preferably 150° to 170°, and in particular to about 160°.  
   
     
     
         8 . Safety belt apparatus in accordance with one of the preceding claims, 
 characterized in that 
 the cam ring ( 18 ) has a central bore ( 19 ) rotatably journalled on a central hollow bearing spigot ( 16 ) fixed relative to the housing, within which the hub ( 58 ) of an eccentric disc ( 27 ) is preferably rotationally journalled, and is preferably arranged concentric to the belt reel ( 13 ).  
   
     
     
         9 . Safety belt apparatus in accordance with one of the preceding claims, 
 characterized in that 
 a driver pin ( 24 ) extends from the cam ring ( 18 ) into a driver recess ( 23 ) of the toothed control wheel ( 21 ) complementary to it in the peripheral direction, with the driver recess having a radial extent such that the driver pin ( 24 ) can be freely radially displaced therein during the eccentric movement of the toothed control wheel ( 21 ), with it also being possible to provide the driver pin on the toothed control wheel and the driver recess on the cam ring.  
   
     
     
         10 . Safety belt apparatus in accordance with one of the  claims 2  to  9 , 
 characterized in that 
 an actuating plunger ( 22 ) of the micro-switch ( 59 ) cooperates with the switching cam track (( 49 ) in such a way that the micro-switch ( 50 ) deactivates the belt tensioner ( 35 ) when the safety belt ( 11 ) is drawn in and over a restricted draw out range adjoining it and activates the belt tensioner with a draw outwhich goes beyond the restricted draw outrange.  
 
 
     
     
         11 . Safety belt apparatus in accordance with  claim 10 , 
 characterized in that 
 the actuating plunger ( 22 ) is thrust radially outwardly by the switching cam track ( 49 ) against the spring force ( 59 ) when the safety belt ( 11 ) is drawn in and, on the far side of the restricted draw out range, is shifted by spring force ( 59 ) onto the switching cam track ( 49 ) which drops away radially inwardly.  
   
     
     
         12 . Safety belt apparatus in accordance with one of the  claims 2  to  11 , 
 characterized in that 
 the belt tensioner is activated by the micro-switch ( 50 ) after a belt draw out of 400 mm to 800, preferably 50 mm to 700, and in particular of about 600 mm.  
 
 
     
     
         13 . Safety belt apparatus in accordance with one of the preceding claims, 
 characterized in that 
 when the belt is drawn in from the fully drawn out state up to a drawn out belt length of 400 m to 800, preferably 500 mm to 700 mm, and in particular about 600 mm, only a belt draw in is possible, but not a belt pull out, and in that with a greater belt draw in the blocking pawl ( 17 ) is brought out of engagement with the toothed ratchet wheel ( 29 ) and the belt tensioner is simultaneously deactivated.  
   
     
     
         14 . Safety belt apparatus for vehicles, in particular motor vehicles having at least one safety belt ( 11 ), which is wound to a greater or lesser degree onto a belt reel ( 13 ) rotatably secured on the vehicle chassis about an axis of rotation ( 12 ) and preferably biased by a spring retraction mechanism, in particular a spiral spring ( 15 ) in the belt winding up direction, and having a belt draw out blocking mechanism ( 26 ,  38 ), which, with-an attempted rapid draw out of the safety belt ( 11 ), blocks a further draw out of the safety belt ( 11 ), with a toothed ratchet wheel ( 29 ) being rotationally coupled to the belt reel ( 13 ) with a small rotary clearance ( 77 ) and being so spring biased in the belt unwinding direction of rotation of the belt reel ( 13 ) relative to the latter that it is located in the biasing direction at the end of the rotary clearance ( 77 ), wherein, when the belt draw out blocking mechanism ( 26 ,  38 ) becomes effective and the tension force is maintained at the safety belt ( 11 ), an engageable pawl  61  mounted on the belt reel ( 13 ) is brought into engagement with a ring of teeth ( 65 ) secured to a housing, whereupon a further draw out of the safety belt ( 11 ) is stopped, in particular in accordance with one or more of the preceding claims, 
 characterized in that 
 the draw out blocking mechanism has a rotary acceleration lever ( 38 ) pivotable about a pivot axis ( 68 ) extending parallel to the belt reel axis ( 12 ), and having, at one end, at least one blocking tooth ( 69 ), which, on pivoting of the rotary acceleration lever ( 38 ), can be brought into or out of engagement with an inner toothed arrangement ( 26 ) of a toothed ring support member ( 25 ) arranged fixed relative to the housing preferably concentric to the toothed ratchet wheel ( 29 ), wherein the rotary acceleration lever ( 38 ) is normally held out of engagement with the inner toothed arrangement ( 26 ) by a resetting spring ( 70 ), but comes into blocking engagement with the inner toothed arrangement ( 26 ), with rotary accelerations in the belt draw out direction above a predetermined rotary acceleration boundary value.  
 
 
     
     
         15 . Safety belt apparatus in accordance with  claim 14 , characterized in that the rotary acceleration lever ( 38 ) has two lever arms ( 38 ′,  38 ″), of which the one is provided with the blocking tooth ( 69 ), and the other is arranged relative to the pivot axis ( 68 ) such that it exerts a torque onto the rotary acceleration lever ( 38 ) in the blocking direction, with rotary accelerations in the belt draw out direction, which leads above the predetermined rotary acceleration limit value to a rotation of the rotary acceleration lever ( 38 ) against the force of the spring ( 70 ) in the blocking direction.  
     
     
         16 . Safety belt apparatus in accordance with  claim 14  or  15 , characterized in that the two arms ( 38 ′,  38 ″) of the rotary acceleration lever ( 38 ) are shaped and are provided with mass such that a torque is only exerted on the rotary acceleration lever ( 38 ) by rotary acceleration, but not by rotary speeds.  
     
     
         17 . Safety belt apparatus in accordance with one of the  claims 14  to  16 , characterized in that the abutments ( 71 ,  72 ,  73 ,  74 ,  75 ) restrict the pivotal movements of the rotary acceleration lever ( 38 ).  
     
     
         18 . Safety belt apparatus in accordance with one of the preceding claims, characterized in that a curved elongate hole ( 76 ) is provided in the toothed ratchet wheel ( 29 ) extending substantially radially with a peripheral component and receives a guide spigot ( 62 ′) concentric to the axis ( 63 ) of the engageable pawl ( 61 ); and in that the engageable pawl ( 61 ) is rotatably mounted on the belt reel ( 13 ) preferably radially inwardly of the guide spigot ( 62 ′) about an axis ( 63 ) which extends parallel to the axis ( 12 ) of the belt reel ( 13 ).  
     
     
         19 . Safety belt apparatus in accordance with one of the preceding claims, characterized in that the number and arrangement of the teeth of the inner toothed arrangement ( 26 ) and of the inner toothed ring ( 65 ) are selected relative to one another such that on blocking of the rotation of the toothed ratchet wheel ( 29 ) by engagement of the blocking tooth ( 69 ) into the inner toothed arrangement ( 26 ), the teeth ( 64 ′) of the engageable pawl ( 61 ) are aligned with the tooth recesses ( 65 ) in the peripheral direction in such a way that with a relative rotation between the belt reel ( 13 ) and the stationary toothed ratchet wheel ( 29 ), a problem-free engagement of the teeth ( 64 ′) into the tooth recesses ( 65 ′) is ensured.  
     
     
         20 . Safety belt apparatus in accordance with one of the preceding claims, characterized in that the rotary clearance spring ( 67 ) is so strongly made that the toothed ratchet wheel ( 29 ) is driven with the same speed of rotation of the belt reel ( 13 ) with the normally arising rotary accelerations of the belt reel ( 13 ) in the belt draw out direction and in that the rotary clearance ( 77 ) is first overcome against the force of the rotary clearance spring ( 67 ) when the blocking tooth ( 69 ) is engaged into the inner toothed arrangement ( 26 ).