Abstract:
An automotive door hinge assembly is provided with a hold-open device with a leaf spring member carried on a first part of a hinge assembly, and a compound roller carried on a second part of the hinge assembly, wherein the compound roller engages the leaf spring member with the combination of a flexible and resilient first material portion and a hard, rigid second material portion of the roller assembly during its motion between the door open and door closed positions.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to automobile door hinges and more specifically to such hinges which provide door check means for holding the door in an open position. 
     BACKGROUND OF THE INVENTION 
     It is well known in the automotive door hinge art to provide check spring mechanisms which function to exert a force on the portion of a hinge carrying the door to control movement to and away from the fully opened position of the door. For example, one automotive manufacturer employs a hinge in certain automobiles it produces which includes a bent-over strike tang on the door portion of the hinge which slides along and compresses a leaf spring member carried on the body portion of the hinge to control movement about the fully opened position. While this has been shown to be a simple and effective mechanism, lubrication is required for easy and quiet operation, and the maintaining of contact with the leaf spring during hold open operation increases the cyclic stress life requirements of the components. 
     Other examples of prior art hinges may be seen in U.S. Pat. No. 3,370,317 to Marchione and U.S. Pat. No. 3,931,664 to Makano et al. These devices both discloses rather complex structures employing rollers engaging the check spring. Both are disadvantageously complex for some applications and the later requires significant lubrication to facilitate the long rolling contact of its rollers with its spring. 
     Another example of a door hinge with an integral check is U.S. Pat. No. 4,532,675 issued to Salazar. This automotive door hinge assembly provides a hold-open device consisting of a leaf spring carried on the body part of the hinge and a roller carried in a cage portion of the door part which engages the leaf spring only during the portion of its travel proximate the door-open position. The roller in this door hinge is disclosed as preferably formed from reinforced nylon. While this has been shown to be a simple and effective mechanism, it has been found that the reinforced nylon roller typically does not wear in a uniform manner about its circumferential periphery. As a result, the reinforced nylon roller begins to contact the leaf spring in the same position during the open and close cycle, thereby wearing down particular portions of the cylindrical circumference, which results in a loss of the door check means for holding the door in the open position after repeated cycling of the mechanism. 
     SUMMARY OF THE INVENTION 
     The present invention seeks to increase the operable life of the door hinge mechanism while providing for easy and quiet operation. This is accomplished by replacing the reinforced nylon roller of the previous door hinge mechanism with a composite construction having a very hard spool or rim made of material such as metal and a softer, more pliable, annular ring engaged on the spool. The softer and more pliable annular ring preferably has a greater external diameter than the outermost diameter of the spool or rim. In the preferred embodiment, the spool or rim is made from sintered steel or other metal and the annular silencer ring is made of polyester urethane or other flexible material capable of withstanding temperatures in the range from 400° F. to -40° F. Various structural configurations are disclosed as options for the improved roller. In each case, the spool or rim of the roller includes a first annular shoulder and a second annular shoulder, wherein the diameter of the first annular shoulder is less than the diameter of the second annular shoulder, and the flexible annular ring has a throughbore adapted to engage on the first annular shoulder of the rim with its outer annular surface extending beyond the diameter of the second annular shoulder of the rim. It has been found that the expected cyclic life of the door hinge mechanism can be increased by providing a metal roller in place of the reinforced nylon roller disclosed in U.S. Pat. No. 4,532,675; however, this results in a door hinge mechanism that does not provide the desired quiet operation. Therefore, the present invention resolves this problem by providing a compound roller structure including the combination of a sintered steel roller or rim with a polyester urethane silencer or annular ring disposed on the sintered steel rim. 
     The present invention also provides a polyester urethane block or projection to urge the contoured leaf spring outwardly from the flat mounting portion of the door hinge assembly. The polyester urethane is also the preferred material for this portion of the door hinge assembly because it meets the temperature requirements of being capable of withstanding a temperature range between 400° F. and -40° F. The 400° F. temperature is required in order to withstand the paint baking process which automobiles are typically exposed to, and the -40° F. temperature is required in order to withstand the sub zero temperatures that automobiles are occasionally exposed to during normal use. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects, features and advantages of the present invention will become readily apparent to those skilled in the automotive door hinge art from the following description, reference being made to the accompanying drawings in which like reference numerals refer to like parts throughout the various views wherein: 
     FIG. 1 is a perspective view of the hinge of the present invention in the door closed position; 
     FIG. 2 is a cross-sectional view of the hinge of the present invention in the door closed position taken along line 2--2 of FIG. 1; 
     FIG. 3 is a cross-sectional view similar to FIG. 2 wherein the hinge of the present invention is shown in the first stop of a door-open position; 
     FIG. 4 is a cross-sectional detail view of a composite roller according to the present invention; 
     FIG. 5 is a cross-sectional detail view of a second embodiment of the compound roller according to the present invention; and 
     FIG. 6 is a cross-sectional detail view of a third embodiment of the composite roller according to the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings and in particular to FIG. 1 thereof, a hinge assembly 10 is illustrated as including generally a first plate 12 and a second plate 14 pivotally interconnected through a pin 16. The first plate 12, as can best be seen in FIG. 2 and 3, includes a flat mounting portion 18 for abuttingly engaging a portion of a vehicle body and further includes upstanding bracket portions 22 for mounting the pin 16. Attachment of the mounting portion 18 to the vehicle body is preferably accomplished by conventional fasteners. A leaf spring member 28 is secured to the outer face 29 of the mounting part 18 by means of rivets 30. The leaf spring member 28 is preferably formed of one metal plate having a generally contoured surface providing first and second generally concave portions. It is urged generally outwardly toward the pivotal axis of pin 16 by provision of a flexible resilient block of material 32 disposed between the outer face 29 and the leaf spring member 28. In the preferred embodiment, the block of flexible and resilient material is made of polyester urethane, or any other similar material having the desired flexibility and resilience in addition to being capable of withstanding temperatures in a range from 400° F. to -40° F. for extended periods of time. A pair of stop portions 34 are formed in the brackets 22 of the first plate 12 adjacent the free end of the leaf spring member 28. 
     The second plate 14 includes a pair of mounting ears 38 through which conventional fasteners are inserted for fastening to a portion of the door of a vehicle. The second plate 14 also includes a cage portion 44 which is configured to receive the pin 16 and includes a pair of depending rolled-over tabs 46 for defining a pair of aligned apertures 48 for rotatably mounting a roller 50. The roller 50 is preferably formed with a compound structure having a very hard spool or rim 52 made of a material, such as metal, and a softer, more pliable, annular silencer 54 engaged on the spool 52. The softer and more pliable annular silencer 54 preferably has a greater external diameter than the outermost diameter of the spool or rim 52. In the preferred embodiment, the spool or rim 52 is made of sintered steel or other metal, and the annular silencer 54 is made of polyester urethane or other flexible material capable of withstanding temperatures in the range from 400° F. to -40° F. 
     Various structural configurations are shown in FIGS. 4-6 for the dual roller assembly 50. In each case, the spool or rim 52 of the roller 50 includes a first annular shoulder 56 and a second annular shoulder 58, wherein the diameter of the first annular shoulder 56 is less than the diameter of the second annular shoulder 58, and the flexible annular silencer 54 has a throughbore adapted to engage on the first annular shoulder 56 of the rim 52 with its outer annular surface extending beyond the diameter of the second annular shoulder 58 on the rim 52. FIG. 4 depicts the preferred embodiment of the roller assembly 50. In the preferred embodiment, as shown in FIG. 4, the roller assembly 50 includes first and second spools 52. Each spool 52 having a first annular shoulder 56 and a second annular shoulder 58, wherein the first annular shoulder 56 has a diameter less than the diameter of the second annular shoulder 58. The silencer ring 54 having a throughbore adapted to engage the first annular shoulder 56 and further having an outer cylindrical periphery with a diameter greater than the diameter of the second annular shoulder 58. It has been found that the silencer ring 54 decreases the noise of operation of the hinge mechanism while the hard material spool 52 increases the longevity of the mechanism. The roller assembly 50 is mounted on pin 60 to allow rotation of the roller assembly 50 as it contacts the leaf spring member 28. 
     An optional configuration can be seen in FIG. 5, wherein the spool 52 is an assembly including a first portion having the first annular shoulder 56 and at least one second portion having the second annular shoulder 58. As depicted in FIG. 5, the silencer ring 54 is disposed on top of the first portion and this assembly is interposed between first and second portions having the second annular shoulder 58. Of course, this assembly may be attached together by any known means, or it may be retained as shown by generally spanning the entire longitudinal distance of pin 60 extending between the bent over tabs 46. 
     The embodiment of the roller assembly 50 as depicted in FIG. 6 is a simplified version of that previously shown and described in FIG. 4. In this embodiment, a single piece spool or rim 52 is provided having a first annular shoulder 56 and a second annular shoulder 58, wherein the first annular shoulder 56 has a diameter less than the diameter of the second annular shoulder 58. A silencer ring 54 has a throughbore adapted to engage with the first annular shoulder 56 and further has an outer cylindrical surface with a diameter greater than the diameter of the second annular shoulder 58. The spool or rim 52 has a throughbore in each case of the three embodiments shown in FIGS. 4-6 adapted to engage with pin 60 positioned within apertures 48 formed by rolled-over tabs 46 of cage portion 44. The configuration for the roller assembly 50 depicted in FIG. 6, may also include a second portion of the spool or rim as depicted in FIG. 5 to assist in maintaining the silencer ring 54 on the first annular shoulder 56 of the spool 52. In addition, the spool 52 may be sized accordingly to generally span the entire longitudinal length of pin 60 between the rolled-over tabs 46 of the cage portion 44. 
     Operation of the preferred embodiment can best be understood by reference to FIGS. 2 and 3 in which the closed and partially open positions of the hinge assembly 10 are illustrated. It can be seen that in the door closed position of FIG. 2, the roller 50 carried in cage portion 44 of the door plate 14 is spaced from the upper surface of the leaf spring member 28. Upon movement of the door toward the open position of FIG. 3, the roller 50 is brought into engagement with the surface of the leaf spring member 28 and deflects the leaf spring member 28 inwardly toward the body of the vehicle. After reaching the position shown in FIG. 3, the roller 50 is generally disposed within the first generally concave portion 24 of the leaf spring member 28 providing first check means of the door in a partially open position. Further movement of the door in a counter clockwise rotation about pin 16 will dispose the roller assembly 50 at the second generally concave portion 26 of leaf spring member 28 adjacent the terminus edge of the leaf spring member 28. The roller 50 is maintained in rolling contact with the leaf spring member 28 during its movement through the first and second generally concave portions 24 and 26 of the leaf spring member 28. Each of the generally concave portions 24 and 26 of the leaf spring member 28 provide door check means for holding the door in an open position. The generally concave portion 24 holds the door in a partially open position, while the generally concave portion 26 holds the door in the outermost open position of its movement. Clockwise movement toward the closed position from the open position is resisted by the leaf spring member 28 when the roller 50 is engaged within the generally concave portions 24 and 26 of the leaf spring member 28. Movement in the opening direction is limited by the stops 34 which are abuttingly engageable with edges of the cage portion 44. 
     It has been found that the operation described proceeds smoothly owing to the rolling contact between the roller assembly 50 and the leaf spring member 28 and it has been further found that lubrication of the upper surface of the leaf spring member 28 is usually unnecessary using this compound dual element structure for the roller assembly. 
     While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation permissible under law so as to encompass all such modifications and equivalent structures.