Patent Publication Number: US-2003234554-A1

Title: Hinged motor-vehicle armrest

Description:
FIELD OF THE INVENTION  
       [0001] The present invention relates to a hinged part. More particularly this invention concerns a hinged motor-vehicle armrest.  
       BACKGROUND OF THE INVENTION  
       [0002] A standard motor-vehicle armrest as described in German patent document 198 12 432 filed Mar. 21, 1998 by N. Lotz et al. This structure has a support, a fixed hinge plate secured to the support, a movable hinge plate pivotal on the fixed hinge plate about an axis, and a latch between the plates for angularly locking the plates relative to each other. An armrest is secured to the movable hinge plate, so that when the plates are locked by the latch means, the armrest cannot move angularly relative to the support. The pivot for the armrest is braced by a spring so that if the armrest is forced downward, this spring is loaded. Thus the spring is always in the force-transmission path. Such a system is relatively complex.  
       OBJECTS OF THE INVENTION  
       [0003] It is therefore an object of the present invention to provide an improved pivotal cover, in particular a motor-vehicle armrest.  
       [0004] Another object is the provision of such an improved armrest which overcomes the above-given disadvantage, that is which is of simple construction.  
       SUMMARY OF THE INVENTION  
       [0005] An armrest assembly has according to the invention a support, an at least partially elastomeric mounting block having one side operatively secured to the support and another side, a fixed hinge plate operatively secured to the other side of the mounting block, and a movable hinge plate pivotal on the fixed hinge plate about an axis. A latch between the plates can angularly lock the plates relative to each other. An armrest is secured to the movable hinge plate so that, when the plates are locked by the latch means, angular displacement of the armrest relative to the support deforms the block.  
       [0006] Thus this elastic block, whose elasticity of about 100 Shore A is substantially more than that of any of the other normally metallic parts of the assembly, deforms to allow the armrest to deflect. The mounting block is very simple yet can withstand considerable forces so as to have a long service life. Since the elastomeric block is integrated right into the hinge, it is located exactly where the torque applied to the armrest is best dealt with. The modules of elasticity and/or compression and/or torque can be quite high so that when subjected to compression and/or shear, the block returns without permanent deformation or damage to its original shape. It is possible to build such a block or blocks right into the structure in a manner substantially reducing manufacturing costs for the armrest assembly, making it particularly effective when used as a central rear-seat drop-down armrest. When no force is pressing down on the armrest, the mounting block is not significantly deformed. Furthermore a slide-type guide as described in the above-mentioned German patent document is not needed.  
       [0007] According to the invention the one side of the block is directly secured to the support. More particularly, one or two screws bearing on the block and seated in the support secure the support to the block.  
       [0008] The block in accordance with the invention is entirely unitarily formed of an elastomeric material, normally a somewhat stiff plastic.  
       [0009] In one embodiment the block is shaped like a wheel as a flexible openwork structure having a plurality of elastomeric inserts fitted to the structure.  
       [0010] The other side of the block according to the invention is directly secured to the fixed hinge plate. More particularly a pin extending from the fixed hinge plate is seated in the other side of the block.  
       [0011] The fixed hinge plate according to the invention has an axially extending collar and the block is at least partially recessed in the collar. In addition it is generally cup-shaped so that radial outward deformation of the mounting block is restricted. Furthermore the block is formed of elastomeric material in turn formed with at least one cutout. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
     [0012] The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:  
     [0013]FIG. 1 is a horizontal section through the rear end of an arm rest according to the invention;  
     [0014]FIG. 2 is a vertical section taken along line II-II of FIG. 1;  
     [0015]FIG. 3 is a detail sectional view taken along line III-III of FIGS. 1 and 2;  
     [0016]FIG. 4 is a perspective view of the hinge structure according to this invention; and  
     [0017]FIG. 5 is a perspective view of a mounting element according to the invention.  
    
    
     SPECIFIC DESCRIPTION  
     [0018] As seen in FIGS. 1 and 2 a an armrest assembly  1  is carried on a structural support part  2  of a motor vehicle, here between a pair of rear seats, to which a pair of elastomeric and relatively soft mounting blocks  3  and  4  carrying hinges  5  and  6  are secured by bolts  7  and  8 . The support  2  is formed with a pair of aligned holes  9  and  10  through which pass a tubular hinge shaft  11  defining a pivot axis A, received coaxially in a tube  12 .  
     [0019] The hinges  5  and  6  have plates  13  and  14  which are secured to each other by the tube  12  and angularly locked to the blocks  3  and  4  by anchor pins  15  and  16  so that these plates  13  and  14  are connected via the elastomeric blocks  3  and  4  to the support  2 . The hinges  5  and  6  further have movable hinge plates  17  and  18  juxtaposed with the fixed plates  13  and  14  and secured via screws  19  and  20  to the ends of the shaft  11  so that they rotate jointly about the axis A relative to the plates  13  and  14  and the fixed support  2 . The plates  13 ,  14 ,  17 , and  18  are formed of cast aluminum while the coaxial shafts  11  and  12  are of steel and the blocks  3  and  4  are of plastic.  
     [0020] As better shown in FIGS. 3 and 4, the hinge  5 , which is identical to the hinge  6 , has a grease- or silicone-filled brake  21  comprised of a pinion gear  22  meshing with external teeth formed on the movable hinge part  13  so that pivoting about the axis A is damped. A latch pawl  24  pivoted at  25  on the part  13  is urged by a spring  27  into engagement with internal teeth  26  of the part  17  and can be pivoted inward by an unillustrated button-actuated mechanism to allow a seat back  28  secured to the movable hinge parts  17  and  18  to pivot about the axis A, or to be locked in any angular position thereabout.  
     [0021] Since the fixed hinge parts  13  and  14  are secured via the elastomeric blocks  3  and  4  to the support  2 , when the armrest  28  is locked any torque exerted on it about the axis A will result in elastic deformation of the blocks  3  and  4 . Thus the armrest  28  has some give; it can be moved, even when locked in place, without damage to itself or its support  2 .  
     [0022]FIG. 5 shows a wheel-shaped mounting block  30  that can be used instead of the blocks  3  and/or  4 . It has a hard and flexible plastic rim  31  formed with radial webs  36  protecting inward to an inner ring  37  and forming four angularly equispaced holes  32 - 35  for screws allowing it to be bolted to the support  2 . Between the webs  36  are four elastomeric foam inserts  38 - 41  formed with holes or pockets  42  dimensioned to receive the pins  15  and  16  that couple the movable hinge plates  13  and  14  to them. Thus the screws  7  and  8  through the holes  32 - 35  secure the mounting blocks  30  to the support  2  while the pins  15  and  16  seated in the pockets  42  rotationally couple the movable plates  13  and  14  to the mounting blocks  30 . The outer tube  11  is rotatably received in the hole of the center ring  37  so that this block  30  is sure to stay on center.