Abstract:
A pedal assembly ( 12 ) for electronically controlling an engine throttle ( 38 ). The pedal assembly ( 12 ) includes a pedal housing ( 14 ), a pedal arm ( 18 ) pivotally engaging the pedal housing ( 14 ), and an electrical generator ( 30 ) supported by the pedal housing ( 14 ). The pedal arm ( 18 ) is operable between an idle position ( 24 ) and a plurality of operable positions. When the pedal arm ( 18 ) is pivoted to a predetermined operable position ( 50 ), a kickdown member ( 46 ) provides a kickdown feel to a user. Simultaneously, the electrical generator ( 30 ) generates a control signal having a predetermined magnitude causing the automatic transmission ( 42 ) to downshift to a next lower gear. The kickdown member ( 46 ) is adjustable to synchronize the kickdown feel provided by the kickdown member ( 46 ) with the downshift to the next lower gear.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates generally to a pedal assembly having an electrical generator for electronically controlling an engine throttle in a vehicle and a kickdown mechanism for generating a kickdown feel. Specifically, the kickdown mechanism includes a kickdown member to generate the kickdown feel representing a downshift to a lower gear by an automatic transmission.  
         BACKGROUND OF THE INVENTION  
         [0002]    Prior art pedal assemblies generally comprise a pedal housing attached to a vehicle body and a pedal arm pivotally supported by the pedal housing. A series of links and levers, or cables, mechanically connect the pedal assembly to an engine throttle. Therefore, movement of the pedal arm mechanically controls a position of the engine throttle. In addition, a kickdown device is mechanically connected to the pedal assembly. The kickdown device is used to initiate a kickdown, i.e., a downshift to a next lower gear in an automatic transmission. Typically, such downshifts occur when a user desires fast acceleration. For instance, when the pedal arm is pivoted from an idle position to a predetermined operable position, the kickdown device is mechanically engaged to downshift the automatic transmission. As a result, an added force is required to further pivot the pedal arm. This added force provides a sensation to the user that is commonly referred to as a kickdown feel, i.e., the user can “feel” when the kickdown device is engaged, and hence, when the automatic transmission downshifts to the next lower gear.  
           [0003]    Consequently, a large amount of packaging space must be provided within the vehicle to accommodate the mechanical connections to the kickdown device and the engine throttle. However, the space available for the mechanical connections is limited. Hence, recent improvements in the prior art use electrical connections in place of the mechanical connections. Instead of using the mechanical connections to mechanically transmit a position of the pedal arm to the engine throttle or kickdown device, an electrical generator is used to electrically transmit the position of the pedal arm and subsequently control the engine throttle and the kickdown. Replacing the mechanical connections with electrical connections reduces the necessary packaging space for the pedal assembly.  
           [0004]    In prior art electronic pedal assemblies, the electrical generator generates a control signal that varies in magnitude with respect to the position of the pedal arm relative to the pedal housing. The control signal is sent to a controller that is responsive to the electrical generator. A processor in the controller uses the control signal to generate other control signals to control the position of the engine throttle and to control the downshift. In general, the downshift occurs when the control signal has a predetermined magnitude and the controller, in response, instructs the automatic transmission to downshift to the next lower gear. In other words, the controller is programmed to control the automatic transmission to downshift to the next lower gear when the control signal has the predetermined magnitude.  
           [0005]    Unfortunately, without the mechanical connections, electronic pedal assemblies do not provide the customary feel and performance of a mechanically connected pedal assembly. In other words, the pedal assembly does not provide the kickdown feel to the user when the downshift occurs, i.e., the user cannot “feel” when the downshift occurs. To solve this problem, manufacturers incorporate a kickdown mechanism in the electronic pedal assembly to provide the kickdown feel to the user. The kickdown mechanism is markedly different than the kickdown device described above. The kickdown device is mechanically connected to the pedal assembly via a link or cable and mechanically initiates the downshift in the automatic transmission. Conversely, the kickdown mechanism does not initiate the downshift. Unlike the kickdown device, the kickdown mechanism is a stand-alone mechanism simply used to provide the kickdown feel to the user. Typically, the kickdown mechanism provides the added force associated with the kickdown feel via a kickdown member that engages a portion of the pedal arm.  
           [0006]    An example of a kickdown device mechanically connected to the pedal assembly to initiate a downshift in an automatic transmission is shown in U.S. Pat. No. 5,697,253 to Papenhagen et al.  
           [0007]    An example of a kickdown mechanism used in an electronic pedal assembly to provide a kickdown feel is shown in U.S. Pat. No. 6,209,418 to Kalsi et al. The kickdown mechanism in the &#39;418 patent utilizes a kickdown member that engages a portion of a pedal arm.  
           [0008]    Even with the kickdown member to simulate the kickdown feel, prior art electronic pedal assemblies cannot control a position of the kickdown member to ensure that the pedal arm will engage the kickdown member when the pedal arm is at a predetermined operable position. This can present problems when the predetermined operable position coincides with downshifting of the automatic transmission. Without the ability to control a position of the kickdown member, there is a significant likelihood that the kickdown feel provided by the kickdown member will not occur when the downshift occurs. A typical prior art electronic pedal assembly includes many tolerances between the kickdown member and the pedal arm and between the pedal arm and the electrical generator. Thus, a fixed kickdown member is unlikely to be engaged by the pedal arm when the pedal arm is at the predetermined operable position. Therefore, there exists a need in the art for an electronic pedal assembly capable of adjusting the kickdown member and ensuring that the pedal arm is at the predetermined operable position when the pedal arm engages the kickdown member.  
         BRIEF SUMMARY OF THE INVENTION  
         [0009]    The present invention provides a pedal assembly for use in a vehicle. The pedal assembly comprises a pedal housing. A pedal arm pivotally engages the pedal housing and operates between an idle position and a plurality of operable positions. A kickdown member engages a portion of the pedal arm when the pedal arm is pivoted to a predetermined operable position from the idle position. A force required to further pivot the pedal arm after the pedal arm reaches the predetermined operable position is greater than a force required to pivot the pedal arm from the idle position to the predetermined operable position. An electrical generator is supported by the pedal housing to generate a control signal that varies in magnitude in proportion to the extent of movement of the pedal arm relative to the pedal housing. An adjustment mechanism adjusts the kickdown member relative to the pedal arm to control a position of the kickdown member and ensure that the pedal arm engages the kickdown member when the pedal arm is pivoted to the predetermined operable position.  
           [0010]    A method of providing a kickdown feel in the pedal assembly is also provided. The method includes the steps of detecting the control signal of the electrical generator and moving the pedal arm relative to the pedal housing while detecting the control signal. The kickdown member is then adjusted relative to the pedal arm when the control signal has a predetermined magnitude. As a result, the position of the kickdown member is controlled to ensure that the pedal arm engages the kickdown member when the control signal of the electrical generator is at the predetermined magnitude during operation of the pedal assembly. Hence, the kickdown feel generated by the kickdown member is synchronized with the generation of the control signal at the predetermined magnitude.  
           [0011]    The present invention provides several advantages over the prior art. Notably, the present invention allows a manufacturer to synchronize a downshift to a next lower gear in an automatic transmission with the kickdown feel generated by the kickdown member. For instance, a controller may receive the control signal from the electrical generator and initiate the downshift when the control signal has the predetermined magnitude. Since the kickdown member is adjusted to ensure that the pedal arm engages the kickdown member when the control signal has the predetermined magnitude, the downshift is synchronized with the kickdown feel produced by the kickdown member. 
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0012]    Advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:  
         [0013]    [0013]FIG. 1 is a cross-sectional view of a vehicle having a pedal assembly of the present invention further illustrating an electrical connectivity of the pedal assembly with a controller, engine throttle, and automatic transmission;  
         [0014]    [0014]FIG. 2 is a perspective view of the pedal assembly of the present invention;  
         [0015]    [0015]FIG. 3 is an exploded view of the pedal assembly of the present invention;  
         [0016]    [0016]FIG. 4 is an exploded view of the pedal assembly of the present invention;  
         [0017]    [0017]FIG. 5A is a perspective cut-away view of the pedal assembly of the present invention illustrating an idle position of a pedal arm;  
         [0018]    [0018]FIG. 5B is a perspective cut-away view of the pedal assembly of the present invention illustrating a predetermined operable position of the pedal arm;  
         [0019]    [0019]FIG. 5C is a perspective cut-away view of the pedal assembly of the present invention illustrating a maximum travel position of the pedal arm;  
         [0020]    [0020]FIG. 6A is a cross-sectional view of the pedal assembly illustrating an electrical generator of the pedal assembly when the pedal arm is at the idle position;  
         [0021]    [0021]FIG. 6B is a cross-sectional view of the pedal assembly illustrating the electrical generator of the pedal assembly when the pedal arm is at the predetermined operable position;  
         [0022]    [0022]FIG. 6C is a cross-sectional view of the pedal assembly illustrating the electrical generator of the pedal assembly when the pedal arm is at the maximum travel position;  
         [0023]    [0023]FIG. 7A is an elevational side view of the pedal assembly of the present invention when the pedal arm is at the predetermined operable position; and  
         [0024]    [0024]FIG. 7B is an elevational side view of the pedal assembly of the present invention when the pedal arm is at the maximum travel position. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0025]    Referring to the Figures, wherein like numerals indicate like or corresponding parts throughout the several views, a pedal assembly for use in a vehicle  10  is generally shown at  12 .  
         [0026]    The pedal assembly  12  comprises a pedal housing  14 . The pedal housing  14  is mounted to a vehicle structure of the vehicle  10 , such as a vehicle dash, bracket or frame member  16 , by means well known in the art.  
         [0027]    Referring to FIGS. 1 and 2, a pedal arm  18  having upper  20  and lower  22  ends pivotally engages the pedal housing  14 . The pedal arm  18  is movable between an idle position  24  and a plurality of operable positions. A pedal pad  26  is connected to the lower end  22  of the pedal arm  18 . The upper end  20  of the pedal arm  18  is pivotally attached to the pedal housing  14  by a pivot shaft or pin  28 . The pedal arm  18  is preferably formed from steel or polymeric material and the pedal housing  14  is preferably made from a polymeric material such as nylon. It should be appreciated, however, that the material used in the pedal assembly  12  is not intended to limit the present invention.  
         [0028]    The pedal housing  14  supports an electrical generator  30 . The electrical generator  30  is best shown in FIGS.  6 A- 6 C. The electrical generator  30  generates a control signal that varies in magnitude in proportion to the extent of movement of the pedal arm  18  relative to the pedal housing  14 . The electrical generator  30  is typically a potentiometer. However, other generators or sensors known in the art can be used such as non-contact Hall effect sensors, and the like. In the preferred embodiment, the electrical generator  30  includes a sensing arm  32  that wipes across a plurality of sensing bands  34 . The magnitude of the control signal varies as the sensing arm  32  moves across the sensing bands  34 , i.e., the sensing bands  34  are resistors and the control signal varies as the resistance varies.  
         [0029]    Referring back to FIG. 1, the control signal is sent to a controller (not shown) having a computer processor  36  that uses the control signal to control an engine throttle  38 . When the controller receives the control signal from the electrical generator  30 , the processor  36  generates a second control signal to control the position of the engine throttle  38 . These control signals are communicated along electrical connections, as is well known in the art. The engine throttle  38  regulates the amount of fuel that enters a vehicle engine  40  based on the varying control signal sent from the electrical generator  30 . The vehicle engine  40  is mechanically connected to an automatic transmission  42  that is shiftable between high and low gear positions. The vehicle engine  40  supplies varying power to the automatic transmission  42 , which controls the magnitude of output speed and torque. Hence, the output speed and torque are dependent on the control signal that represents a position of the pedal arm  18 .  
         [0030]    Occasionally, a user will desire fast acceleration, which requires the automatic transmission  42  to downshift to a next lower gear. Downshifting of the automatic transmission  42  can be accomplished by any means known in the art, including by electrical or mechanical control. In the preferred embodiment, the downshift occurs when the control signal generated by the electrical generator  30  has a predetermined magnitude. During operation, the controller receives the control signal having the predetermined magnitude from the electrical generator  30 , and in response, the processor  36  sends a third control signal to control the automatic transmission  42  and initiate the downshift.  
         [0031]    A kickdown mechanism  44  imparts a kickdown feel to the user. Referring to FIGS.  3 - 5 C, the kickdown mechanism  44  includes a kickdown member  46  that engages a portion  48  of the pedal arm  18  when the pedal arm  18  is pivoted to a predetermined operable position  50  from the idle position  24 . In the preferred embodiment, the predetermined operable position  50  is the position of the pedal arm  18  at which the control signal has the predetermined magnitude. Hence, the downshift is synchronized with the kickdown feel. It should be appreciated, however, that the present invention is not limited to the predetermined operable position  50  being the position of the pedal arm  18  at which the downshift occurs. For instance, the predetermined operable position may be a position of the pedal arm  18  before of after the downshift occurs.  
         [0032]    During operation of the pedal assembly  12 , a force required to further pivot the pedal arm  18  after the pedal arm  18  reaches the predetermined operable position  50  and engages the kickdown member  46  is greater than a force required to pivot the pedal arm  18  from the idle position  24  to the predetermined operable position  50 . Hence, the kickdown member  46  provides the kickdown feel. Any suitable kickdown member capable of providing the kickdown feel may be used. The kickdown feel is imparted to the user&#39;s foot at the pedal pad  26 . Preferably, the kickdown feel occurs when the pedal arm  18  achieves nearly full travel, i.e., close to a maximum travel position  51 . However, other activation points can be utilized.  
         [0033]    Illustration of the pedal arm  18  moving between the idle position  24  and the predetermined operable position  50  and between the predetermined operable position  50  and the maximum travel position  51  is shown in FIGS.  5 A- 5 C and  6 A- 6 C. FIG. 5A shows the pedal arm  18  in the idle position  24 . Here, the portion  48  of the pedal arm  18  has not yet contacted or engaged the kickdown member  46 . FIG. 5B shows the pedal arm  18  in the predetermined operable position  50 . In this position, the portion  48  of the pedal arm  18  has just engaged the kickdown member  46 , thus initiating the kickdown feel. At this position, the electrical generator  30  also transmits the control signal at the predetermined magnitude. FIG. 5C shows the pedal arm  18  in the maximum travel position  51 . Here, the downshift has already occurred and the user has already experienced the kickdown feel via movement of the kickdown member  46 , as will be described further below. FIGS.  6 A- 6 C further illustrate positions of the sensing arm  32  that correspond to the positions  24 , 50 , 51  of the pedal arm  18 .  
         [0034]    An adjustment mechanism  52  adjusts the kickdown member  46  relative to the pedal arm  18  to control a position of the kickdown member  46  and ensure that the portion  48  of the pedal arm  18  engages the kickdown member  46  when the pedal arm is at the predetermined operable position  50 . As previously mentioned, the predetermined operable position  50  corresponds to the downshift of the automatic transmission. Preferably, adjustment of the kickdown member  46  occurs prior to operation of the pedal assembly  12 , e.g., during manufacture. However, in some instances, adjustment may be performed after operation commences, such as after an accident or during routine maintenance.  
         [0035]    In the preferred embodiment, the adjustment mechanism  52  encloses and engages the kickdown member  46 . Specifically, the adjustment mechanism  52  includes a kickdown housing  54  adjustably connected to the pedal housing  14  that encloses and engages the kickdown member  46 .  
         [0036]    Referring to FIGS. 3 and 4, the kickdown housing  54  defines a plurality of slots  56  therein to provide adjustment of the kickdown housing  54  relative to the pedal housing  14 . The kickdown housing  54  includes a main portion  58  and upper  60  and lower  62  flanges connected to the main portion  58  and extending upwardly and downwardly from the main portion  58 . In the preferred embodiment, the plurality of slots  56  are defined in the upper  60  and lower  62  flanges. In particular, first  56   a  and third  56   c  slots are defined in the upper flange  60  and second  56   b  and fourth  56   d  slots are defined in the lower flange  62 . The slots  56  extend parallel to one another and generally transverse to the pedal arm  18 .  
         [0037]    A plurality of adjusting fasteners  64  extend through the slots  56  into projections  67  extending from the pedal housing  14  to adjustably connect the kickdown housing  54  to the pedal housing  14 . Specifically, the plurality of adjusting fasteners  64  extend through the slots  56  into bores  66  defined within the projections  67 . The kickdown housing  54  is adjusted by sliding the kickdown housing  54  relative to the pedal housing  14  along the adjusting fasteners  64 . The kickdown member  46  moves with the kickdown housing  54  during adjustment. Hence, the kickdown member  46  is adjusted by sliding the kickdown housing  54  relative to the pedal housing  14 .  
         [0038]    It should be appreciated that the adjustment mechanism  52  may include any number of slots  56  and adjusting fasteners  64  to adjustably connect the kickdown housing  54  to the pedal housing  14 . In the preferred embodiment, first  64   a,  second  64   b,  third  64   c,  and fourth  64   d  adjusting fasteners extend through the first  56   a,  second  56   b,  third  56   c,  and fourth  56   d  slots, respectively. Furthermore, the first  64   a,  second  64   b,  third  64   c,  and fourth  64   d  adjusting fasteners extend through the first  56   a,  second  56   b,  third  56   c,  and fourth  56   d  slots into first  66   a,  second  66   b,  third  66   c,  and fourth  66   d  bores defined within first  67   a,  second  67   b,  third  67   c,  and fourth  67   d  projections. The bores  66  are formed in the pedal housing  14  to retain the adjusting fasteners  64 .  
         [0039]    The present invention should not be interpreted as being limited to the specific configuration of the adjustment mechanism  52 . For instance, tracks instead of the slots  56  could be used to adjustably connect the kickdown housing  54  to the pedal housing  14 . Furthermore, the adjusting fasteners  64  may be screws, rivets, bolts, and the like to adjustably connect the kickdown housing  54  to the pedal housing  14 .  
         [0040]    A plurality of snug-fit bushings  68  are positioned in the bores  66  in the pedal housing  14 . The adjusting fasteners  64  extend through the slots  56  and the snug-fit bushings  68  into the bores  66  to create a snug-fit between the adjusting fasteners  64  and the pedal housing  14 .  
         [0041]    A pedal arm jacket  70  encloses the portion  48  of the pedal arm  18  that engages the kickdown member  46 . Referring specifically to FIG. 3, the portion  48  of the pedal arm  18  is further defined as a plate  72  connected to the pedal arm  18  and the plate  72  extends perpendicularly from the pedal arm  18  into the pedal arm jacket  70  through an opening  74  (See FIG. 5C) defined between the pedal housing  14  and the pedal arm jacket  70 . In addition, the kickdown member  46  engages the plate  72  through a second opening  75  defined by the pedal arm jacket  70 .  
         [0042]    The pedal arm jacket  70 , kickdown housing  54 , and kickdown member  46  are preferably made from a polymeric material. However, other materials such as steel, aluminum, and the like may be used.  
         [0043]    The kickdown housing  54  includes a lip  76  connected to the main portion  58  that covers a portion  78  of the pedal arm jacket  70 . This is best shown in FIGS.  5 A- 5 C. The lip  76  is slidable across the pedal arm jacket  70  when the kickdown housing  54  is adjusted relative to the pedal housing  14 .  
         [0044]    Referring to FIGS.  5 A- 5 C, the kickdown member  46  is movable relative to the kickdown housing  54 . The kickdown member  46  moves between a rest position and a plurality of active positions. The force required to move the kickdown member  46  relative to the kickdown housing  54  represents the kickdown feel. In particular, detent members  53  that are springably movable into and out of detent pockets  55  in the kickdown housing  54  provide resistance to movement that generate the kickdown feel. FIGS. 5A and 5B show the detent members  53  in the detent pockets  55  as the pedal arm  18  moves between the idle position  24  and the predetermined operable position  50 , i.e., the kickdown member  46  is in the rest position. FIG. 5C shows the detent members  53  being forced out from the detent pockets  55  when the pedal arm  18  moves from the predetermined operable position  50  toward the maximum travel position  51 , i.e., the kickdown member  46  has moved from the rest position to one of the active positions. The user must apply an added force to urge the detent members  53  from the detent pockets  55 .  
         [0045]    The detent members  53  may be made from a springable material and simply deform to generate the kickdown feel. Preferably, the detent members  53  are rollers that springably recess into the kickdown member  46 . A spring (not shown) reacts between upper and lower pairs of the detent members  53  to urge the detent members  53  into the detent pockets  55 . The kickdown member  46  provides the kickdown feel by being resilient to movement as the pedal arm  18  moves from the predetermined operable position  50  toward the maximum travel position  51 . The interaction between the detent members  53  and detent pockets  55  provide this resiliency.  
         [0046]    A spring  57  biases the kickdown member  46  toward the portion  48  of the pedal arm  18 , effectively biasing the detent members  53  into the detent pockets  55 . Thus, the user must apply enough force to urge the detent members  53  from the detent pockets  55  and to overcome the biasing effect of the spring  57  when moving the pedal arm  18  from the predetermined operable position  50  toward the maximum travel position  51 . When the user releases the pedal arm  18  when the pedal arm  18  is between the predetermined operable position  50  and the maximum travel position  51 , e.g., to decelerate, the spring  57  biases the kickdown member  46  toward the portion  48  of the pedal arm  18  and the detent members  53  return to the detent pockets  55 .  
         [0047]    Referring to FIGS. 7A and 7B, the kickdown housing  54  defines a plurality of indicator windows  80  therein to determine the extent of movement between the kickdown member  46  and the kickdown housing  54 . In other words, the indicator windows  80  provide an indication of whether or not the kickdown member  46  has moved relative to the kickdown housing  54 . The indicator windows  80  coextend with the detent pockets  55 . Hence, the detent members  53  should be fully viewable within the indicator windows  80  when the kickdown member  46  is in the rest position. As previously discussed, the kickdown member  46  does not move relative to the kickdown housing  54  during adjustment. The indicator windows  80  are used to ensure that there is no such movement during adjustment. FIG. 7A shows the detent members  53  fully viewable within the indicator windows  80 , i.e., the kickdown member  46  is in the rest position. FIG. 7B shows the kickdown member  46  moved from the rest position to one of the active positions, i.e., only a portion of the detent members  53  can be seen in the indicator windows  80 .  
         [0048]    A method of providing the kickdown feel in the pedal assembly  12  will now be described. The method ultimately synchronizes the kickdown feel with the downshift of the automatic transmission  42 . To start, the method includes the steps of detecting the magnitude of the control signal of the electrical generator  30  and moving the pedal arm  18  relative to the pedal housing  14  while detecting the magnitude of the control signal. The magnitude of the control signal can be measured using any means known to those skilled in the art including applying a voltmeter to the electrical generator  30  and the like. Movement of the pedal arm  18  is discontinued when the control signal has the predetermined magnitude. The pedal arm  18  is secured to prevent further movement relative to the pedal housing  14  once movement of the pedal arm  18  is discontinued.  
         [0049]    Next, the kickdown member  46  is adjusted relative to the pedal arm  18  to ensure that the pedal arm  18  engages the kickdown member  46  when the control signal of the electrical generator  30  is at the predetermined magnitude during operation of the pedal assembly  12 , i.e., the kickdown feel is synchronized with the downshift of the automatic transmission.  
         [0050]    The step of adjusting the kickdown member  46  further includes the step of sliding the kickdown member  46  relative to the pedal arm  18 . This is accomplished by sliding the kickdown housing  54  enclosing the kickdown member  46  relative to the pedal housing  14  and along the plurality of adjusting fasteners  64  extending through the kickdown housing  54  into the pedal housing  14 . At the same time, an assembler views the detent members  53  of the kickdown member  46  through at least one of the indicator windows  80  to ensure that the kickdown member  46  does not move relative to the kickdown housing  54  during adjustment.  
         [0051]    Adjustment of the kickdown member  46  stops when the portion  48  of the pedal arm  18  abuts the kickdown member  46 . Once adjustment of the kickdown member  46  is complete, the kickdown housing  54  is secured to the pedal housing  14  to immobilize the kickdown housing  54  and prevent further adjustment of the kickdown member  46 . The step of securing the kickdown housing  54  to the pedal housing  14  to prevent further adjustment is further defined as compressing or securing the kickdown housing  54  against the pedal housing  14  using the plurality of adjusting fasteners  64 . More specifically, the fasteners are screws that are tightened against the upper  60  and lower  62  flanges and locked into place in the bores  66   a - 66   d  with an epoxy. Finally, the pedal arm  18  is released and the pedal assembly  12  is ready for operation.  
         [0052]    Obviously, many modifications and variations of the present invention are possible in light of the above teachings. The invention may be practiced otherwise than as specifically described within the scope of the appended claims, wherein that which is prior art is antecedent to the novelty set forth in the “characterized by” clause. The novelty is meant to be particularly and distinctly recited in the “characterized by” clause whereas the antecedent recitations merely set forth the old and well-known combination in which the invention resides. These antecedent recitations should be interpreted to cover any combination in which the incentive novelty exercises its utility. In addition, the reference numerals in the claims are merely for convenience and are not to be read in any way as limiting.