Abstract:
An apparatus that may be utilized as a glow plug connector ( 1401 ) includes a retainer ( 1601 ) disposed between retainer flanges ( 2415 ), advantageously in a groove ( 2413 ). The retainer ( 1601 ) is capable of compressing to fit, for example, within a passage of a rocker carrier ( 820 ) of an internal combustion engine, and capable of subsequently expanding to prevent the connector ( 1401 ) from being dislodged from the passage.

Description:
CLAIM OF PRIORITY 
   This patent application claims the benefit of the priority of provisional patent application No. 60/466,867 filed Apr. 30, 2003. 

   FIELD OF THE INVENTION 
   This invention relates to glow plugs for use with internal combustion engines, including but not limited to connectors and related apparatus for use with such glow plugs. 
   BACKGROUND OF THE INVENTION 
   Internal combustion engines commonly employ cold start devices, such as a glow plug, to assist in ignition. Existing engine designs commonly have glow plugs located inside the engine valve cover. A glow plug is generally used to preheat the combustion chamber mixture of a diesel engine or an auto-ignition internal combustion engine to assist in cold starting. The single glow plug corresponding to a combustion chamber is generally secured to or installed in the cylinder head of the engine such that there is an equal number of combustion chambers and glow plugs. For example, a diesel engine with a V-8 configuration has a total of eight glow plugs with four glow plugs on each cylinder bank. 
   Each glow plug is typically electronically connected to a power source via a single glow plug connector attached to an under-cover valve cover wire harness. The under-cover valve cover wire harness is then appropriately electronically connected to an external engine harness that is in turn connected to an engine power source. The interface between under-valve cover and external harnesses provides a sealing function that prevents engine oil leakage. In the interior of the valve cover, the glow plug connectors, attached to the under-cover valve cover wire harness, are individually connected to corresponding glow plugs. This arrangement often times leads to crowding of engine components in the limited space under the valve cover. Also, the installation of each glow plug connector to each glow plug terminal results in increased manufacturing time and costs. 
   Further, mounting existing wire harness glow plug connectors individually to the glow plugs can be difficult, time consuming and requires some force to push and connect the wire harness connectors to the glow plug terminals. The wire harness connectors may be connected manually or with special insertion tools. Due to the limited space under the valve cover, it is difficult to individually install glow plug connectors properly to corresponding glow plug terminals. Many times, the resultant electrical connection between the glow plug connector and the glow plug terminal is at times not secure and electrically inadequate. As a result, electrical testing is typically required to verify that there is adequate electrical contact between the glow plug connector and the glow plug terminal. The required testing is a drawback that also leads to increased engine manufacturing time and cost. 
   Accordingly, there is a need for a glow plug connection apparatus that is easy to install, prevents engine oil leaks, and results in a consistently good electrical connection between the glow plug connector and glow plug, thereby reducing engine manufacturing time and costs. 
   U.S. Pat. No. 6,539,905 
   U.S. Pat. No. 6,539,905 provides a glow plug connection apparatus for electrically connecting to a plurality of glow plugs while simultaneously sealing the engine from oil leakage. The glow plug connection apparatus simultaneously installs a plurality of glow plug connectors to corresponding glow plugs mounted in a cylinder head in an internal combustion engine. The glow plug connection apparatus comprises, a rigid buss bar rail, a plurality of glow plug connectors attached to the rigid buss bar rail, a plurality of connector wires routed in the rigid buss bar rail and electrically connected to corresponding glow plug connectors, a wire router, and a conduit retaining clip between the wire router and the rigid buss bar rail. The rigid buss bar rail and the glow plug connectors preferably form an apparatus connector angle. The glow plug connector wires can terminate in a multi-port glow plug wire connector or a single connection point. 
   Additionally, the glow plug connector of the glow plug connection apparatus preferably comprises a buss bar rail interface section, a sealing section having an O-ring seal able to seal the glow plug connector to a glow plug passage, a guide section having a plurality of guide fins around the periphery of the glow plug connector, and a clip section having a plurality of clip fingers around the periphery of the glow plug connector able to engage a glow plug terminal. In a preferred embodiment, at least one the clip fingers has a protruding lip. The buss bar rail interface section and the glow plug connector body preferably form a glow plug connector angle. 
     FIG. 1  shows a front view of an embodiment of a glow plug connection apparatus  100  according to U.S. Pat. No. 6,539,905. The glow plug connection apparatus  100  comprises a rigid routing or buss bar rail  20 , a plurality of glow plug connectors  10 , a conduit retaining clip  25 , a wire conduit  30 , glow plug connector wires  32 , and a glow plug wire connector  35 . The glow plug connection apparatus  100  is preferably adapted for mounting in a rocker carrier  820  (shown in  FIG. 8 ) which is mounted on a cylinder head (not shown) in an internal combustion engine. The rocker carrier is the subject of U.S. Pat. No. 6,484,683 issued Nov. 26, 2002 to Zielke. Both U.S. Pat. No. 6,539,905 and U.S. Pat. No. 6,484,683 are assigned to a common entity, International Engine Intellectual Property Company, LLC. The rocker carrier generally relates to a device for mounting and securing certain engine related components to a cylinder head, and is incorporated herein by reference. 
     FIG. 1  shows a four position glow plug connection apparatus  100 , with four glow plug connectors  10 , that would be connected to four corresponding glow plugs (shown in  FIG. 10  and  FIG. 11 ) previously mounted on a cylinder head. The glow plug connection apparatus  100  depicted in  FIG. 1  and  FIG. 8  is preferably mounted on the rocker carrier  820  that is mounted on one cylinder head bank side of a V-8 type engine. Those of skill in the art will readily recognize that the glow plug connection apparatus  100  could also be easily modified to cooperatively mount on a rocker carrier for use on a on a six cylinder V-type engine. The glow plug connection apparatus  100  can be modified to comprise more or less glow plug connectors  10  depending on a particular engine application, e.g., three glow plug connectors  10  for one bank of a V-6 type engine. Additionally, the glow plug connection apparatus  100  shown in  FIG. 1  can be mounted on a rocker carrier  820  that is mountable on either cylinder head bank or side of a V-type engine. 
   The buss bar rail  20  is preferably a rigid routing section for internally routing glow plug connector wires  32  between the glow plug connectors  10  and the glow plug wire connector  35 . The buss bar rail is preferably configured of a hollow lengthwise rigid metal or steel section with a rectangular cross-section. The bus bar rail  20  can have other configurations, for example a square, circular or oval cross-section. Further, the hollow rigid steel or metal makeup of the buss bar rail  20  allows the glow plugs wires  32  protects the glow plug wires  32  from heat exposure in the engine compartment due to the engine or other engine components. Also, the glow plug connection apparatus  100  via the rigid buss bar rail  20  allows the glow plug connectors  10  to be simultaneously connected by pushing or pressing down on the rigid buss bar rail  20  until the glow plug connectors  10  engage the corresponding glow plugs  900  (shown in  FIG. 9 ). 
     FIG. 1  shows that the buss bar rail  20  preferably comprises four glow plug connectors  10  attached substantially equidistant and parallel to each other and extending away from the buss bar rail  20  in the same direction. The glow plug connectors  10  are preferably comprised of a buss bar rail interface section  19 , a sealing section  16  with an O-ring seal  18 , a guide section  14  and a clip or snap-fit section  12 . The glow plug connectors  10  are appropriately spaced along the buss bar rail  20  to correspond to glow plugs  900  installed in an engine cylinder head. Further, due to the physical inclined positioning of the glow plugs  900  in the engine cylinder head, the glow plug connectors  10  preferably form an apparatus connector angle  8  with respect to the rigid buss bar rail  20 . In the embodiment shown in  FIG. 1 , the preferred apparatus connector angle  8  is about eighty-three degrees. Those of skill in the art will readily recognize that the apparatus connector angle  8  may vary to compliment the physical inclination of the glow plugs  900  in a particular engine application. The apparatus connector angle  8  also allows the buss bar rail  20  to maintain a substantially parallel relationship to the engine cylinder head or rocker carrier once installed (shown in  FIG. 8 ). 
     FIG. 1  also shows a buss bar retaining clip  25  that is preferably positioned at the interface between the rigid buss bar rail  20  and the wire router or conduit  30 . The wire conduit  30  is in turn attached to the glow plug wire connector  35 . The glow plug wire connector  35  is preferably a four pin connector since there are four glow plug connectors  10  which correspond to four glow plug connector wires  32 . The glow plug wire connector  35  will be plugged into an external engine harness or to a glow plug control module (not shown) where power can then be appropriately delivered. The glow plug wire connector  35 , wire router  30  and bus buss retaining clip  25  combination is shown attached to a left side  40  of the buss bar rail  20 . Those of skill in the art will readily recognize that this combination could also be positioned on an opposite right side  50  of the buss bar rail  20  if needed by a particular engine application. 
   The wire router  30  is preferably a flexible dress cover for ease in moving, positioning and routing the wire router  30  in the engine compartment area. The range of movement of the wire router  30  is enhanced by the buss bar retaining clip  25  which comprises a hinge clip section  24  that moves or pivots about a middle clip point  26 . The glow plug wire connector  35  can thus be more easily routed as needed and plugged into an external engine harness or glow plug control module (not shown). Both the wire router  30  and the buss bar retaining clip  25  are preferably made up of flexible plastic based materials but other materials that allow convenient routing and movement of the glow plug wire connector  35  may be substituted. 
     FIG. 2  shows a front view of the glow plug connector  10  of the glow plug connection apparatus  10  shown in  FIG. 1 . The glow plug connector  10  is preferably comprised of a buss bar rail interface section  19 , a sealing section  16  for use in conjunction with an O-ring seal  18  (shown in  FIG. 1 ), a guide section  14  and a clip or snap-fit section  12  that engages a top portion of the glow plug  913  (shown in  FIG. 9 ). The buss bar rail interface section  19  is attached to the buss bar rail  20  as shown in  FIG. 1 . The buss bar interface section  19  is preferably inclined with respect to the glow plug connector body  10  by a glow plug connector angle  210 . The preferred glow plug connector angle  210  is about eighty-three degrees. However, those of skill in the art will readily recognize that the glow plug connector angle  210  may vary depending on the physical inclination of the glow plugs  900  installed in a particular engine application. The glow plug connector angle  210  allows the glow plug connector  10  and the buss bar rail  20  to be attached in such a manner that the buss bar rail  20  can maintain a substantially parallel relationship to the engine cylinder head once the glow plug connection apparatus  100  is installed. This aspect results in the apparatus connector angle  8  discussed and shown in  FIG. 1 . Additionally, there is shown a portion of a glow plug connector wire  232  extending from the buss bar rail interface section  19  which connects the glow plug connector  10  to the glow plug wire connector  35 . 
     FIG. 2  also shows in more detail the sealing section  16  that comprises an O-ring holder area  218  and a seating section  216 . The O-ring holder area  218  is configured to hold an O-ring seal  18  (shown in  FIG. 1 ) which will seal a glow plug passage  810  (shown in  FIG. 8 ) in the rocker carrier. The O-ring seal  18  is preferably comprised of a rubber based material, e.g., it can be a TEFLON®-coated VITON® O-ring. Other materials that accomplish the sealing function may instead be used. The seating section  216  is preferably configured to have an external tapered seating face  217 . The tapered seating face  21  engages a complimentarily configured top glow plug passage section  816  (shown in  FIG. 8 ) of the rocker carrier  820  when the glow plug connection apparatus  100  is installed. The O-ring seal  18  and the tapered seating face  217  allow the glow plug connectors  10  to be appropriately sealed in the rocker carrier  820  and to properly sit on the top glow plug passage  816  when the glow plug connection apparatus  100  is installed (shown in  FIG. 8 ). 
     FIG. 2  also shows the guide section  14  which is preferably comprised of a plurality of guide fins  214  positioned in a substantially vertical manner around the periphery of a glow plug connector midsection  213 . The guide fins  214  will appropriately align or position the glow plug connector  10  in glow plug passages  810  (shown in  FIG. 8 ) to allow the glow plug connectors  10  to more easily travel in the glow plug passages  810  and thereby more easily and properly connect with the glow plugs  900  installed in the cylinder head (not shown). The guide fins  214  also give the glow plug connector  10  added structural strength and stability. The preferred embodiment shown in  FIG. 2  comprises four guide fins  214  (shown in  FIG. 5 ) spaced equidistantly at about 90 degrees from each other around the periphery of the connector midsection  213  for positioning of the glow plug connectors  10 . Those of skill in the art will readily recognize that more or less fins could be used to accomplish the same function. Also, the degree distance  514  (shown in  FIG. 5 ) between the guide fins  214  may be different from guide fin  214  to guide fin  214  so long as the proper positioning of the glow plug connector  10  in the glow plug passage  810  is achieved. 
   Further,  FIG. 2  shows the glow plug clip section  12  at the bottom of the glow plug connector  10 . The glow plug clip section  12  is preferably comprised of a plurality of clip fingers  212  positioned around the bottom periphery of the glow plug connector  10 . In the embodiment shown, the glow plug clip section  12  comprises four clip fingers  212  (shown in  FIG. 3 ) spaced equidistantly from each other around the bottom periphery of the glow plug connector  10 . This physical arrangement results in finger spacings  211  between the clip fingers  212  that are equidistantly spaced at 90 degrees from each other (shown in  FIG. 3 ). The equidistant finger spacings  211  allow for more efficient or equal distribution of forces encountered by the clip fingers  212 . The clip fingers  212  preferably have a resilient and spring-like property so that they can expand and contract as required when a glow plug  900  is inserted into or removed from the glow plug connector  10 . During installation of the glow plug connection apparatus  100 , the clip fingers  212  expand to accept a glow plug terminal  912  (shown in  FIG. 12 ) and then contract to secure the electrical connection to the glow plug terminal  912 . Those of skill in the art will readily recognize that more or less clip fingers  212  could be used so long as the desired electrical connection of the glow plug connector  10  to the glow plug  900  is achieved and secured. Though equidistant spacing is preferred, the resultant finger spacings  211  between clip fingers  212  could be different from clip finger  212  to clip finger depending on a particular application. 
     FIG. 3  shows a cross-sectional view of the clip section  12  along a section line C—C of the glow plug connector  10  shown in  FIG. 2 .  FIG. 3  clearly illustrates that in a preferred embodiment, the glow plug connector  10  clip section  12  is comprised of four clip fingers  212  equidistantly positioned around the periphery of a glow plug connector  10  and separated by four resulting finger spacings  211 . The finger spacing  211  are preferably equidistantly spaced at 90 degrees apart from each other. The equidistant clip finger  212  arrangement allows for more efficient or equal distribution of forces encountered by the clip fingers  212  when a glow plug  900  is inserted or removed upon installation or removal of the glow plug connection apparatus  100 . 
     FIG. 4  shows a side view of the glow plug connector shown in  FIG. 2 . A preferred configuration of the guide fins  214  is illustrated where the guide fin bottom  415  has an inclined construction. In this embodiment, the guide fin bottom  415  forms a fin angle  414  with the glow plug connector  10  of about 38 degrees. The guide fin angle  414  will ease the initial insertion of the glow plug connectors  10  into the glow plug passages  810  of the rocker carrier  820  (shown in  FIG. 8 ). Those of skill in the art will recognize that other guide fin angles  414  would also accomplish the same function.  FIG. 4  also shows a cutaway view A—A of the glow plug clip section  12  that partially highlights a preferred interior protruding lip  412  configuration of the clip fingers  212 . The protruding lip  412  is an important part of the clip fingers  212  since it  412  is in part responsible for holding and securing the electrical connection between the glow plug connectors  10  to the glow plug  900 . 
     FIG. 5  shows a cross-sectional view of the guide section  14  along the section line B—B of the glow plug connector  10  shown in  FIG. 4 .  FIG. 5  shows that in the preferred embodiment, the glow plug  10  is comprised of four guide fins  214  spaced equidistantly at 90 degrees from each other around the periphery of the connector midsection  213 . As noted previously, the guide fins  214  properly align or position the glow plug connector  10  in the glow plug passages  810  of the rocker carrier  820 . More or less guide fins  214  could be used and the degree distance  514  between the guide fins  214  may be different from guide fin  214  to guide fin  214  so long as the proper alignment or positioning of the glow plug connector  10  in the glow plug passage  810  is achieved.  FIG. 5  also shows the glow plug connector interior  510  which will preferably house a female type connector  1010  (shown in  FIG. 10  and  FIG. 11 ). The female type connector  1010  is internally electrically connected (not shown) to the glow plug connector wire  32  (shown in  FIG. 1 ) and accepts the insertion of the glow plug terminal tip  914  (shown in  FIG. 9  and  FIG. 11 ). 
     FIG. 6  shows an enlarged detail of view A—A of the clip section  12  of the glow plug connector  10  showing a preferred interior configuration of the clip finger  212 . The interiorly protruding lip  412  is an important aspect of the clip fingers  212 . In conjunction with the resilient and spring-like nature of the clip fingers  212 , it is the protruding lip  412  that is responsible for ultimately holding and securing the electrical connection between the glow plug connectors  10  to the glow plug  900 . The protruding lip  412  preferably extends along the interior periphery of the clip finger  212  near the finger bottom  612  and each clip finger  212  preferably has a protruding lip  412 . This allows for a better and more secure connection between the glow plug connectors  10  to the glow plug  900 . Those of skill in the art will readily recognize that the protruding lip  412  could also extend only partially along the interior of the clip finger  212  or could be present in less than all the clip fingers  212 . The preferred configuration of the clip fingers  212  results in a “snap-on” or “click-on” feature that allows an operator or installer to know when the glow plug connectors  10  are properly installed on the glow plugs  900 . 
     FIG. 7  shows a rear view of the glow plug connector shown in  FIG. 2 . More particularly,  FIG. 7  shows that the seating section  216  has a tapered seating face angle  716 , which is preferably about 40 degrees. The tapered seating face  217  will interact with a complimentarily configured top glow plug passage section  816  of the glow plug passage  810  (shown in  FIG. 8 ). The tapered seating face  217  allows the glow plug connectors  10  to properly sit on or engage the top glow plug passage section  816  of the glow plug passage once the glow plug connection apparatus  100  is installed (shown in  FIG. 8 ). The tapered seating face angle  716  may take on other values complimentary to the top glow plug passage section  816 . 
     FIG. 8  shows an embodiment of the rigid glow plug connection apparatus  100  mounted on a rocker carrier  820  with a valve cover  830 , where the four glow plug connectors  10  are preferably mounted in the respective glow plug passages  810  of the rocker carrier  820 . There is shown a rocker carrier  820  adapted for use with a cylinder head (not shown) in an internal combustion engine, e.g., on either engine bank or side of a V-8 type diesel engine. There is also shown a valve cover  830  that secures to the top periphery  827  of the rocker carrier  820  to thereby enclose the cylinder head. One of the various features of the rocker carrier  820  is that rocker arm assemblies with associated rocker arms (not shown) and other related components can be mounted to the rocker carrier  820 . 
   Among other configurations, the rocker carrier  820  comprises a plurality of glow plug passages  810  in or adjacent to a front rocker carrier wall  825 . The glow plug passages  810  preferably have an inclined or angled configuration in the front wall  825  of the rocker carrier  820 . In this manner, the glow plug passages  810  are complimentary to the angled or inclined glow plug connectors  10  of the glow plug connection apparatus  100 . There is also shown the inclined nature of the top glow plug passage section  816  of the glow plug passage  810 . The top glow plug passage section  816  is preferably configured or angled to compliment the angled or inclined tapered seating face  217  (shown in  FIG. 2 ) of the glow plug connector  10  sealing section  16 . In this manner, the connection to the glow plugs  900  (shown in  FIG. 9  through  FIG. 11 ) can be appropriately sealed via the O-ring seal  18  (shown in  FIG. 1 ) on the sealing section  16 . 
   In order to install the glow plug connection apparatus  100  (also shown in  FIG. 2 ), an installer preferably positions the buss bar rail  20  such that all the glow plug connectors  10  are inserted into the appropriate glow plug passages  810  of the rocker carrier  820 . Next, the installer pushes or presses downward on the rigid buss bar rail  20  which thereby applies simultaneous force on the glow plug connectors  10 . The glow plug guide sections  14 , via the guide fins  414 , align the glow plug connectors  10 , as force is applied, for proper electrical connection to the glow plug terminal  912 . This allows the glow plug connectors  10  to be simultaneously connected when the glow plug connectors  10  engage corresponding glow plug terminals  914  on the glow plugs  900  (shown in  FIG. 9 ). 
   As the glow plug connectors  10  are pushed into place, the each glow plug terminal  912  enters the connector clip section  12 . As the glow plug connector  10  continues moving downward, the glow plug clip fingers  212  encounter the glow plug terminal head  913 . At this point, the configuration of the glow plug terminal head  913  forces the clip fingers  212  to expand as they continue to travel downward. When the clip section  12  reaches the glow plug terminal neck  915  the clip fingers  212  will rapidly contract and compressively seat around the periphery of the glow plug terminal neck  915 . This rapid contraction results in a “snap” or “click” that typically should be audible to the installer. The installer also should be able to “feel” when the clip fingers have snapped onto the glow plug  900 . Thus, the installer will know that there is a good electrical connection when he hears or “feels” the glow plug connectors  10  “snap-on” or “click-on” to the glow plug terminals  912 . 
   At this point, the glow plug terminal tip  914  is inserted and electrically connected to the female type connector  1010  in the glow plug connection interior (shown in  FIG. 10  and  FIG. 11 ) which is in turn connected (not shown) to the glow plug connector wire  32  (shown in  FIG. 1 ). Also, the glow plug connectors  10  are now appropriately sealed against the glow plug passages  810  via the O-ring seal  18  and tapered seating face  217  of the sealing section  16  acting on the top glow plug passage section  816 . If the glow plug connectors  10  are not properly installed, the O-ring seal should be visible. This is a signal to the installer that the glow plug connection apparatus needs to be reinstalled. Further, the rigid buss bar rail  20  should now be substantially parallel to the engine cylinder head (not shown) upon which the rocker carrier  820  is or will be installed. The rigid buss bar rail  20  is preferably parallel to the engine cylinder head to, among other things, minimize the amount of space used in the engine compartment. The glow plug wire connector  35  can now be plugged into an external engine harness, glow plug control module or other appropriate engine component for delivery of power to the glow plugs. 
     FIG. 9  shows a typical glow plug  900  that could be used with the glow plug connectors shown in  FIG. 1 through 8 . The glow plug  900  generally comprises a glow plug terminal  912 , a cylindrical metal glow plug tube or body  905  and a heating element  903 . The cylindrically tube  905  comprises the housing of the glow plug  900  that attaches to the cylinder head or engine block (not shown). The glow plug  900  is preferably threaded to the cylinder head or engine block via glow plug threads  907  on the exterior of the glow plug  900 . The is also a glow plug terminal  912  at the top of the glow plug  900  that is insulated  908  from the glow plug body  905  and electrically connected to the heating element  903 . The glow plug terminal  912  is comprised of a terminal tip  914 , a terminal head  915  and a terminal neck  915 . The heating element  903  is generally comprised of a ceramic heating element tip  903  that will heat up when power or electric current is applied to the glow plug terminal  912  to provide heat to the diesel mixture in the combustion chamber (not shown). 
   As discussed previously with respect to  FIG. 8 , the glow plug terminal tip  914  is inserted and electrically connected to the female type connector  1010  (shown in  FIG. 10  and  FIG. 11 ) which is in turn connected (not shown) to the glow plug connector wire  32  (shown in  FIG. 1 ). Also, the configuration of the glow plug terminal head  913  forces the resilient connector clip fingers  212  to expand as they travel around the terminal head  913 . When the resilient connector clip section  12  reaches the glow plug terminal neck  915 , the resilient connector clip fingers  212  rapidly contract and compressively seat around the periphery of the glow plug terminal neck  915 . The installer will hear or “feel” when the connector clip fingers  212  snap or click onto the glow plug  900 . The configuration of the glow plug terminal  914  and the make up of the glow plug connector  10  allows the installer to know when there is a good electrical connection when he/she hears or “feels” the glow plug connectors  10  “snap-on” or “click-on” to the glow plug terminal neck  915 . 
     FIG. 10  shows a front view of an embodiment of the glow plug connection apparatus  100  with an installed glow plug  900 .  FIG. 10  shows three glow plug connectors  10  attached to the rigid buss bar rail  20  in a substantially equidistant and parallel manner and extending away from the buss bar rail  20 .  FIG. 10  also depicts a cutaway glow plug connector  1012  with a female type connector  1010  which is housed in the glow plug connector interior  510  (shown in  FIG. 5 ). The female type connector  1010  is internally electrically connected (not shown) to the glow plug connector wire  32  (shown in  FIG. 1 ) and accepts the insertion of the glow plug terminal  912  (shown in  FIG. 11 ). There is also shown the clip fingers  212  of the snap fit section  12  that will additionally secure the glow plug connector  10  to the glow plug  900  at the glow plug terminal  912 . 
     FIG. 11  shows the cutaway glow plug connector  1012  of  FIG. 10  with an installed glow  900 .  FIG. 11  shows that the terminal tip  914  of the glow plug terminal  912  is inserted in the female type connector  1010  of the glow plug connector  1012 .  FIG. 11  also shows that the clip fingers  212  extend past the glow plug terminal head  913  and down to the glow plug terminal neck  912  to secure and connect the glow plug connectors  10  and  1012  to the glow plug  900 . 
     FIG. 12  shows a perspective front view of an alternate embodiment of the glow plug connection apparatus  1200  adapted for mounting in a rocker carrier  820 , similar to that shown in  FIG. 8 . The embodiment of the glow plug connection apparatus  1200  shown in  FIG. 12  preferably comprises a rigid buss bar rail  1220 , a plurality of glow plug connectors  1210 , glow plug connector wires  1232 , and a glow plug wire connector  1235 . The rigid bus bar rail  1220 , of this embodiment, additionally comprises strengthening and support sections  1222 . The rigid buss bar  1220  has four glow plug connectors  1210  attached in a substantially equidistant and parallel manner and extending away from the buss bar rail  1220  in the same direction. The glow plug connectors  10  are preferably comprised of a buss bar rail interface section  1219 , a sealing section  1216  with an O-ring seal  1218 , a guide section  1214  and a clip or snap-fit section  1212  that engages the glow plug  900  (similar to that shown in  FIG. 10 ). The glow plug connection apparatus  1210  is connected to the rocker carrier  820  (shown in  FIG. 8 ) and the glow plugs (shown in  FIG. 9 ) in a fashion as previously described in  FIG. 8 . 
     FIG. 13  shows a partial view of an alternate embodiment of the termination of the glow plug connector wires  1332 . In this embodiment, the glow plug connector wires  1332  preferably terminate at a single connection point  1335  instead of a multi-port glow plug wire connector  35  and  1235  as depicted in  FIG. 1  and  FIG. 12 . In this embodiment, the glow plug connector wires  1332  have a single termination point thus power or electrical current is either provided to all or none of the glow plugs  900  (not shown) simultaneously. This is a configuration that could be useful in some engine applications. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  through  FIG. 13  illustrate a glow plug connection apparatus in various views from U.S. Pat. No. 6,539,905. 
       FIG. 14  is a harness assembly in accordance with the invention. 
       FIG. 15  is a close-up of the glow plug connector in accordance with the invention. 
       FIG. 16  is a properly inserted glow plug connector within a part of a rocker carrier  1603  in accordance with the invention. 
       FIG. 17  is a harness assembly that utilizes flexible wire conduit in accordance with the invention. 
       FIG. 18  and  FIG. 19  illustrate the harness assembly with each glow plug connector inserted into the rocker carrier in accordance with the invention. 
       FIG. 20  is a side view of the glow plug connector with a retainer installed in accordance with the invention. 
       FIG. 21  is an inner glow plug terminal disposed within the glow plug connector in accordance with the invention. 
       FIG. 22  is a cross-sectional view of the connector showing the glow plug terminal in relation to the glow plug connector in accordance with the invention. 
       FIG. 23  is illustrates a cross-section of the glow plug connector disposed within a rocker carrier in accordance with the invention. 
       FIG. 24  illustrates a side view of the glow plug connector without a seal and retainer in accordance with the invention. 
       FIG. 25  illustrates a side view of the glow plug connector with a seal and retainer in accordance with the invention. 
       FIG. 26  is a top view of the retainer in accordance with the invention. 
       FIG. 27  illustrates retention arms disposed with respect to an expandable spring in accordance with the invention. 
       FIG. 28  is a side view of the retainer in accordance with the invention. 
       FIG. 29  is a cross-section of the connector as taken through the retainer groove in accordance with the invention. 
   

   DETAILED DESCRIPTION 
   The following describes an apparatus for and method of connecting wires to a glow plug. A harness assembly includes a plurality of glow plug connectors, each of which connects to a glow plug for an internal combustion engine. The harness assembly and glow plug connectors described herein may be modified for use with spark plugs and engine sensors, including multi-wire sensors. 
     FIG. 14  shows a harness assembly  1400  for a plurality of glow plug connectors  1401 . The harness assembly  1400  includes a glow plug wire connector  1403  that connects a power source to glow plug wires  1405  for each of the glow plug connectors  1401 . The glow plug wires  1405  extend through a wire conduit  1407 , which may be flexible or rigid wire conduit, and a T-connector  1409  for each glow plug connector  1401 . A close-up of the glow plug connector  1401  is shown in  FIG. 15 . 
     FIG. 16  illustrates a properly inserted glow plug connector  1401  within a part of a rocker carrier  1603 , as viewed from inside the rocker carrier  1603  where the glow plugs are disposed. Inside each glow plug connector  1401  is a glow plug terminal  1605  that provides electrical connection to the glow plug, as shown in  FIG. 16 . A retention arm  1607  that is part of a retainer  1601  is also shown. 
     FIG. 17  shows a harness assembly  1400  that utilizes flexible wire conduit  1407 .  FIG. 18  and  FIG. 19  illustrate the harness assembly  1400  with each glow plug connector  1401  inserted into the rocker carrier  1603  of an internal combustion engine. The harness assembly  1400  and/or glow plug connectors  1401  described herein may be utilized, for example, with V-type, inline, or L-type engines. 
     FIG. 20 . is a side view of the glow plug connector  1401  with the retainer  1601  installed.  FIG. 21  illustrates the inner glow plug terminal  1605  disposed within the glow plug connector  1401 .  FIG. 22  is a cross-sectional view of the glow plug connector  1401  showing the glow plug terminal  1605  in relation to the connector  1401 . The part of the glow plug connector  1401  that surrounds the glow plug terminal  1605  may be comprised of velox material. 
     FIG. 23  illustrates a cross-section of the glow plug connector  1401  disposed within an opening in a rocker carrier  1603 , showing compression of an O-ring seal  2303  and a stopper  2301 . Once the outer diameter of the O-ring seal  2303  is no longer visible above the rocker carrier  1603 , the glow plug connector  1401  is properly mounted. Once the glow plug connector  1401  is installed, retention arms  1607  for the retainer  1601  expand below the surface of the rocker carrier  1603 . 
     FIG. 24  illustrates a side view of the glow plug connector  1401  without the seal  2303  and the retainer  1601 , and  FIG. 25  illustrates a side view of the glow plug connector  1401  with the seal  2303  and the retainer  1601 . An upper flange  2401  is encased within a lower portion of the T-connector  1409 , as shown in  FIG. 14 . An installation tool groove  2403  is located between an installation flange  2405  and the stopper  2301  of the connector  1401 . An installation tool is inserted into the installation tool groove  2403  in order to assist with the installation and removal of the glow plug connector  1401 . 
   The stopper  2301  is advantageously configured to have an external tapered seating face  2407 . The tapered seating face  2407  engages a complimentarily configured top glow plug passage section  816  (shown in  FIG. 8 ) of the rocker carrier  1603  when the glow plug connector  1401  is installed. The O-ring seal  2303  and the tapered seating face  2407  allow the glow plug connectors  1401  to be appropriately sealed in the rocker carrier  1603  and to be properly disposed in the top glow plug passage  816  when the glow plug connectors  1401  are installed. 
   A pair of seal flanges  2409  and a seal groove  2411  are configured to hold an O-ring type seal  2303  as shown in  FIG. 23  and  FIG. 25  to seal a glow plug passage  810  (as shown in  FIG. 8 ) in the rocker carrier  1603 . The O-ring seal  2303  is advantageously comprised of a rubber-based material, e.g., a Teflon coated Viton O-ring. Other materials may instead be utilized to accomplish the sealing function. 
   A retainer groove  2413  is disposed between a pair of retainer flanges  2415  such that the retainer  1601  may be disposed in the groove between the retainer flanges  2415 . An optional overmold  2417  is provided to secure the retainer  1601  to the connector  1401 , thereby preventing the retainer  1601  from becoming dislodged from the connector  1401 . A spacer  2419  is disposed between the seal flanges  2409  and the retainer flanges  2415  to provide a suitable length for the glow plug connector  1401  to mate with the glow plug. 
     FIG. 26  illustrates a top view of the retainer  1601 . The retainer  1601  is used to positively retain the glow plug connector  1401  in the rocker carrier  1603 . The retention arms  1607  are angled on both sides, allowing the retainer  1601  to compress as the glow plug connector  1401  is inserted into the rocker carrier  1603  and to snap back to its full dimensions once inside the engine. The angle on the opposite side allows the connector  1401  to also be removed from the rocker carrier  1603  without damage to either the connector  1401  or the engine. The retainer  1601  is advantageously comprised of a metal or metal alloy that is compressible, expandable, and at least slightly flexible. A retention arm  1607  is disposed at each end of an expandable spring  2601 . The expandable spring  2601  expands as it encompasses the retainer groove  2413 , then contracts slightly once in place (as shown in  FIG. 29 ). The expandable spring  2601  advantageously has curved section having a partially circular segment at one end and a u-shaped section at the other end. The retention arms  1607  are disposed at each end of the expandable spring  2601 . Compression of the retention arms  1607  toward each other compresses the expandable spring  2601 , and driving the retention arms  1607  apart expands the expandable spring  2601 . The retention arms  1607  are advantageously disposed perpendicular to the expandable spring  2601 , as shown in  FIG. 27 . 
     FIG. 28  illustrates a side view of the retainer  1601 . The retention arms  1607  are shown each comprising an outer member  2801  and an inner member  2803  that are disposed at an angle with respect to each other. The retention arms  1607  may advantageously be disposed in the same plane, and the retention arms  1607  may advantageously be disposed in a plane substantially perpendicular to the plane in which the expandable spring  2601  is disposed. When the glow plug connector  1401  is inserted into the rocker carrier  1603 , the inner members  2803  compress such that the retainer  1601  fits within the glow plug passage  810  of the rocker carrier  1603  as the glow plug connector  1401  is inserted. Once the elbow, where the outer member  2801  and inner member  2803  meet, clears the end of the glow plug passage  810 , the retention arms  1607  expand and hold the glow plug connector  1401  in the rocker carrier  1603 . When the glow plug connector  1401  is removed from the rocker carrier  1603 , the outer members  2801  compress such that the retainer  1601  fits within the glow plug passage  810  of the rocker carrier  1603  as the glow plug connector  1401  is removed. 
     FIG. 29  shows a cross-section of the connector as taken through the retainer groove  2413 , when the retainer  1601  is disposed on the connector  1401 . The retainer groove  2413  advantageously runs only partially around the outer diameter of the glow plug connector  1401  between the retainer flanges  2415 . A retainer locator  2901  between the retainer flanges  2415  is utilized to orient the retainer  1601  to the glow plug connector  1401 , with a certain amount of play between the retainer  1601  and the retainer locator  2901 . 
   The present invention provides the advantage of positively connecting glow plug connectors within a rocker carrier by use of a retainer. The retainer is flexible, which facilitates installation and removal, in addition to securing the glow plug connector within the rocker carrier. Installation and removal are facilitated by providing a groove in which an installation tool may be inserted. The apparatus may be utilized in other applications than glow plug connection. 
   The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.