Patent Publication Number: US-6901634-B2

Title: Door check device with insert molded roller

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a door check device for installation between a motor vehicle body and a motor vehicle door. 
   2. Description of Related Art 
   Door check devices are well-known in the art for use in checking the swinging motion of vehicle doors. There are many different types of door check devices, but all of them function to hold a vehicle door in a predetermined position, thereby preventing a door from closing on its own (or preventing it from opening further). 
   Most door check devices have a profiled link member that is engaged by one or two rollers. In this type of system, a link member is mounted on either the vehicle door or the vehicle itself. The roller is mounted on a roller mounting pin that is mounted on the opposite part, such that if the link member is mounted to the vehicle, the roller is mounted to the door and vice-versa. The profile of the link member has one or more detents in which the roller(s) is/are received under spring biasing. This engagement checks the door in its predetermined position. Some of these rollers are made out of metal. This causes problems because the metal roller rubs against other metal parts within the door check device, particularly the shaft or pin on which it is normally mounted, thereby creating squeaks and noises. Although lubrication can temporarily quiet the squeaks and noises, the lubrication has to be applied often to work effectively. This creates a maintenance task that is undesirable. Also, the presence of excess grease can be problematic during the painting process of the vehicle. 
   Another type of roller, is made from metal with a press-fit plastic bushing. This type of roller has certain drawbacks. When the vehicle is subjected to the painting process, high temperatures are used. The high temperatures cause the plastic bushing to be stress-relieved and shrink. Once the bushing has shrunk, the press-fit interference may be lost such that the bushing no longer rotates with the metal roller. This can cause the roller to seize on the roller mounting pin and create loud noises. Typically lubrication is used to alleviate the undesirable noises, however this introduces the problems inherent with lubrication as outlined above. 
   Rollers are subjected to relatively high wear and tear. Therefore, rollers made from plastic alone are not acceptable because plastic rollers will wear out quickly. 
   Thus, it would be desirable to provide an improved door check device with a roller that will have a long life, yet be quiet in operation, and not require lubrication. 
   SUMMARY OF THE INVENTION 
   One embodiment of the present invention provides a door check device for installation between a motor vehicle body and a motor vehicle door that swings in opposing opening and closing directions relative to the vehicle body. The door check includes a first mounting bracket, a second mounting bracket having at least one roller mounting pin, a link member, and a roller. The first mounting bracket is constructed and arranged to be mounted on one of a vehicle door and a vehicle body and the second mounting bracket is constructed and arranged to be mounted on the other such that the first and second mounting brackets move relative to one another as the door is swung in the opposing opening and closing directions. The link member is carried by the first mounting bracket. The roller is carried by the second mounting bracket on the roller mounting pin such that the link member is in contact with the roller. The roller includes a metal core having an internal bore in which the roller mounting pin is received and a plastic bushing lining the internal bore of the metal core. The metal core and the plastic bushing have interlocked or bonded structures that essentially prevent relative rotation between the metal core and the plastic bushing. 
   These and other objects, features, and advantages of this invention will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, which are part of this disclosure and which illustrate, by way of example, the principles of this invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings facilitate an understanding of the various embodiments of the present invention. In the drawings: 
       FIG. 1  is a perspective view of a door check device with a portion of the housing removed for clarity purposes, the device illustrated also functioning as a door hinge; 
       FIG. 2  is a perspective view of one embodiment of a roller for use in the door check device of  FIG. 1 ; 
       FIG. 3  is a perspective view of another embodiment of the roller; 
       FIG. 4  is a perspective view of another embodiment of the roller; 
       FIG. 5  is a perspective view of another embodiment of the roller; 
       FIG. 6  is a perspective view of another embodiment of the roller; and 
       FIG. 7  is a perspective view of a separate door check device. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  illustrates a door check device  10  for installation between a motor vehicle body and a motor vehicle door that swings in opposing opening and closing directions relative to the vehicle body. The construction of the motor vehicle and the door thereof are not considered to be part of the present invention and thus will not be detailed herein. Instead, the present invention is concerned with the door check device  10 . 
   The door check device  10  includes a first mounting bracket  12 , a second mounting bracket  14 , a link member  16 , a roller  20 , a roller mounting pin  21 , and a biasing member  18 . The first mounting bracket  12  is constructed and arranged to be mounted on one of a vehicle door and a vehicle body. The second mounting bracket  14  is constructed and arranged to be mounted on the other of the vehicle door and the vehicle body such that the first  12  and second  14  mounting brackets move relative to one another as the door is swung in the opposing opening and closing directions thereof relative to the vehicle body. In the illustrated embodiment, the first mounting bracket  12  is constructed to be mounted to the vehicle door and the second mounting bracket  14  is constructed to be mounted to the vehicle body. However, in any given embodiment of the present invention the first mounting bracket  12  could be mounted to the vehicle body and the second mounting bracket  14  could be mounted to the vehicle door. 
   The door check device  10  illustrated in  FIG. 1  is an integrated check with the first  12  and second  14  mounting brackets pivotally coupled together for hingedly supporting the vehicle door. Alternatively, the door check device  10  may be constructed such that the first  12  and second  14  mounting brackets are separate from one another and do not provide hinged support. This is referred to as a separate check. 
   The first  12  and second  14  mounting brackets can be constructed from any suitable material, including but not limited to steel. The brackets  12 ,  14  may be cast, machined, or formed in any suitable manner. Preferably, the brackets  12 ,  14  are stamped from steel. 
   The link member  16  is connected to the first mounting bracket  12 . The link member  16  can be made from any suitable material, including but not limited to steel. The link member  16  may be cast, machined, or formed in any suitable manner. Preferably, the link member  16  is stamped from steel. 
   The roller  20  is rotatably mounted on a roller mounting pin  21  that is attached to the second mounting bracket  14 . The roller  20  is in rolling contact with the link member  16  to control relative movement between the first  12  and second  14  mounting brackets, and hence the vehicle door during the opening and closing movements of the vehicle door. Specifically, the link member  16  has a series of detents  17  thereon. The roller  20  is received within these detents  17  to releasably maintain in checked positions. The roller  20  rotates about a rotational axis  22 . 
   The roller mounting pin  21  can be constructed from any suitable material, including but not limited to steel. The roller mounting pin  21  can be attached to the second mounting bracket  14  by conventional arrangement, including but not limited to welding. Alternatively, the roller mounting pin  21  can be integrally formed with the second mounting bracket  14  itself. 
   The biasing member  18  includes a first end and a second end. The first end is fixedly attached to the first mounting bracket  12 . The second end of the biasing member  18  is in contact with the link member  16 , such that it provides enough pressure to the link member  16  to keep the link member  16  in contact with the roller  20 . In particular, the biasing member  18  keeps the link member  16  in biased contact with the roller  20  so that when the roller  20  is received within any given detent  17 , sufficient pressure to overcome the bias must be applied to the door to disengage the roller  20  and the detent  17 . This provides the checking action that releasably maintains the door in predetermined positions. Preferably, the biasing member  18  is a spring. 
     FIGS. 2-6  illustrate different embodiments of the roller  20 . The roller  20  includes a metal core  24  that has an internal bore  25 , and a molded plastic bushing  26  that lines the internal bore  25  of the metal core  24 . The metal core  24  and the plastic bushing  26  have interlocked structures  30  that essentially prevent relative rotation between the metal core  24  and the plastic bushing  26 . 
   In one embodiment, the interlocked structures  30  include at least one tooth  32  on one of the metal core  24  and the molded plastic bushing  26  and at least one slot  34  on the other of the metal core  24  and the molded plastic bushing  26 . In other words, the tooth  32  can be part of either the metal core  24  or the molded plastic bushing  26 . If the tooth  32  is part of the metal core  24 , then the slot  34  is part of the molded plastic bushing  26  and vice-versa. The tooth  32  is disposed within the slot  34  to provide the interlocked structures  30  and essentially prevent the relative rotation between the metal core  24  and the molded plastic bushing  26 . Alternatively, the interlocked structures  30  may include a plurality of teeth  32  on the metal core  24  and a plurality of teeth  33  on the plastic bushing  26  such that the pluralities of teeth  32 ,  33  are intermeshed to essentially prevent the rotation between the metal core  24  and the plastic bushing  26 . 
   In the preferred embodiment, as illustrated in  FIG. 2 , the plastic bushing  26  further includes a generally radially extending flange  28  disposed at each end of the metal core  24 . The metal core  24  further includes a generally radially extending flange  36  at each end of the metal core  24  that face each flange  28  of the plastic bushing  26 . The interlocked structures  30  include at least one tooth  32  on one of each flange  36  of the metal core  24  and each flange  28  of the plastic bushing  26  and at least one slot  34  on the other of the metal core  24  and the plastic bushing  26 , such that the tooth  32  is disposed within the slot  34  to essentially prevent the relative rotation between the metal core  24  and the plastic bushing  26 . Alternatively, the interlocked structures  30  include a plurality of teeth  32  on each flange  36  of the metal core  24  and a plurality of teeth  33  on each flange  28  of the plastic bushing  26  such that the pluralities of teeth  32 ,  33  are intermeshed to essentially prevent the relative rotation between the metal core  24  and the plastic bushing  26 . 
   In another embodiment, as illustrated in  FIG. 3 , the plastic bushing  26  further includes a generally radially extending flange  28  disposed at each end of the metal core  24 . The interlocked structures  30  include at least one tooth  32  on one of each end of the metal core  24  and each flange  28  of the plastic bushing  26  and at least one slot  34  on the other of the metal core  24  and the plastic bushing  26 , such that the tooth  32  is disposed within the slot  34  to essentially prevent the relative rotation between the metal core  24  and the plastic bushing  26 . Alternatively, the interlocked structures  30  include a plurality of teeth  32  on each end of the metal core  24  and a plurality of teeth  33  on each flange  28  of the plastic bushing  26  such that the pluralities of teeth  32 ,  33  are intermeshed to essentially prevent the relative rotation between the metal core  24  and the plastic bushing  26 . 
   In another embodiment, as illustrated in  FIG. 4 , the plastic bushing  26  further includes a generally radially extending flange  28  disposed at an end of the metal core  24 . The end of the metal core  24  further includes a generally radially extending flange  36  that faces the flange  28  of the plastic bushing  26 . The interlocked structures  30  include at least one tooth  32  on one of the flange  36  of the metal core  24  and the flange  28  of the plastic bushing  26  and at least one slot  34  on the other of the metal core  24  and the plastic bushing  26 , such that the tooth  32  is disposed within the slot  34  to essentially prevent the relative rotation between the metal core  24  and the plastic bushing  26 . Alternatively, the interlocked structures  30  may include a plurality of teeth  32  on the flange  36  of the metal core  24  and a plurality of teeth  33  on the flange  28  of the plastic bushing  26  such that the pluralities of teeth  32 ,  33  are intermeshed to essentially prevent the relative rotation between the metal core  24  and the plastic bushing  26 . 
   In another embodiment, as illustrated in  FIG. 5 , the plastic bushing  26  further includes a generally radially extending flange  28  disposed at an end of the metal core  24 . The interlocked structures  30  are provided on the end of the metal core  24  and the flange  28  of the plastic bushing  26 . The interlocked structures  30  may include at least one tooth  32  on one of the end of the metal core  24  and the flange  28  of the plastic bushing  26  and at least one slot  34  on the other of the metal core  24  and the plastic bushing  26 , such that the tooth  32  is disposed within the slot  34  to essentially prevent the relative rotation between the metal core  24  and the plastic bushing  26 . Alternatively, the interlocked structures  30  may include a plurality of teeth  32  on the end of the metal core  24  and a plurality of teeth  33  on the flange  28  of the plastic bushing  26  such that the pluralities of teeth  32 ,  33  are intermeshed to essentially prevent the relative rotation between the metal core  24  and the plastic bushing  26 . 
   In yet another embodiment, as illustrated in  FIG. 6 , the interlocked structures  30  may be disposed parallel to the rotational axis  22  of the roller  20 . The interlocked structures  30  may include at least one tooth  32  on one of the internal bore  25  of the metal core  24  and the plastic bushing  26  and at least one slot  34  on the other of the metal core  24  and the plastic bushing  26 , such that the tooth  32  is disposed within the slot  34  to essentially prevent the relative rotation between the metal core  24  and the plastic bushing  26 . Alternatively, the interlocked structures  30  may include a plurality of teeth  32  on the internal bore  25  of the metal core  24  and a plurality of teeth  33  on the plastic bushing such that the pluralities of teeth  32 ,  33  are intermeshed to essentially prevent the relative rotation between the metal core  24  and the plastic bushing  26 . 
   In yet another embodiment, not illustrated, the plastic bushing  26  may be bonded to the metal core  24  using an adhesive. 
   The metal core  24  may be manufactured from any suitable material, including but not limited to steel and composite materials. Preferably, the metal core  24  is steel. Conventional processes may be used to create the metal core  24 , including but not limited to machining and casting. Preferably, the metal core  24  is cold headed and machined. 
   The molded plastic can also contain additives for at least one of strength and lubrication. Preferably, the plastic bushing  26  is molded from a blend of nylon, polytetrafluoroethylene (“PTFE”) and glass fibers. The PTFE provides additional lubrication, thereby eliminating the need for grease or other external lubricants, and the glass fibers reinforce the blended nylon and PTFE. 
   In the preferred embodiment, after the metal core  24  has been created, it is inserted in an injection molding machine. The plastic bushing  26  is then insert molded onto the metal core, thereby creating the roller  20 . The metal core  24  acts as a mold for one surface of the plastic bushing  26  while it is in the molding machine. Any teeth  32  or slots  34  that are disposed on the metal core  24  will help form the corresponding slots  34  or teeth  32  on the plastic bushing, respectively, thereby creating the interlocked structures  30 . Thus, when the roller  20  is discharged from the molding machine, either the teeth  32  and slots  34 , or the plurality of teeth  32  will be intermeshed. Alternatively, a two-piece plastic bushing  26  may be fabricated without the insert molding process by standard molding techniques well known in the art. A two-piece bushing may be press fit or bonded into the internal bore  25  of the metal core  24 . 
   Once the roller  20  is installed in the door check device  10  and the door check device is installed on the motor vehicle, the motor vehicle is subjected to a painting process. This process generally involves high heat. With the interlocked structures  30  of the roller  20  of this invention, any shrinkage of the plastic bushing  26  after the painting process will not affect the performance of the roller  20  in the door check device  10  because the metal core  24  and the plastic bushing  26  will still rotate together. The shrinkage of the plastic material is not enough to withdraw the teeth  32 ,  33  from their interlocked engagement. 
   A roller  20  with a plastic bushing  26  that includes flanges  28  at each end has additional advantages. First, the flanges  28  prevent axial movement of the metal core  24 . Second, the flanges  28  prevent contact between the metal core  24  and other metal components of the door check device  10 , thereby providing quiet operation. Although a non-insert molded two-piece plastic bushing  26  can provide flanges  28  at each end of the metal core  24 , the two pieces may become separated over time and one piece may slip out of alignment, thereby potentially exposing the metal core  24  to other metal parts. Thus, it is preferable to create the plastic bushing  26  via the insert molding process. 
   Although the description heretofore has been specifically directed to integrated door checks, it is envisioned that the roller of this invention may be used in non-integrated, or separate, door checks. In a separate door check, the first and second mounting brackets are separate from one another and do not provide hinged support. For example,  FIG. 7  illustrates a separate door check device  50  that includes a first mounting plate  52 , a second mounting plate  54 , a housing  56 , an elongated link member  58  with at least one swell  60 . The inner workings disposed within the housing  56  are not detailed here as this illustration is intended to generally describe separate door check devices so that they are distinguished from integrated door check devices. The first mounting plate  52  is mounted on one of a vehicle door and a vehicle body. The second mounting plate  54  is mounted on the other of the vehicle door and vehicle body such that the first  52  and second  54  mounting brackets move relative to one another as the door is swung in the opposing opening and closing directions thereof relative to the vehicle body. The elongated link member  58  passes through the housing  56 . At least one roller (not shown) is disposed within the housing  56 . As the roller rotates about a rotational axis, the elongated link member  58  is moved relative to the housing  56 . The position of the elongated link member  58  can be indexed by the at least one swell  60 . It is recognized that the roller  20  of the present invention discussed in detail heretofore can be used in this door check device  50 . 
   While preferred embodiments of the invention have been shown and described, it is evident that variations and modifications are possible that are within the spirit and scope of the preferred embodiments described herein.