Abstract:
The subject matter disclosed herein relates to an improved pedal assembly comprising a service brake and parking brake. The assembly can be employed for operating a wide range of vehicles such as all terrain vehicles, lawn equipment and tractors, utility cars, and is especially desirable for use on golf car operation.

Description:
[0001]    The subject matter disclosed herein claims benefit of prior filed U.S. Patent Application Serial No. 60/226,824, filed on Aug. 22, 2000 and Application Serial No. 60/166,062, filed on Nov. 17, 1999 in the names of Porter et al., and entitled “Pedal Assembly”; the disclosures of which are hereby incorporated by reference. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The instant invention relates to an improved pedal assembly comprising a service brake, parking brake and in some cases an accelerator. The assembly can be employed for operating a wide range of vehicles such as all terrain vehicles, lawn equipment and tractors, utility cars, and is especially desirable for use in golf car operation.  
         BACKGROUND OF THE INVENTION  
         [0003]    Conventional pedal assemblies are used as an interface between an operator and a vehicle so that the vehicle can be operated by pedal controls. These controls are typically in the form of a pedal assembly comprising a service brake, parking brake and in some cases an accelerator. Power can be supplied to the vehicle by an electric motor or internal combustion engine.  
           [0004]    Conventional pedal assemblies contain a large number of components and are time consuming to assemble. Conventional pedal assemblies, for example, golf cars are relatively complex and include multiple pivot points, linkages, springs, pawls, ratchets, among other components. Conventional pedal assemblies may permit unintended operation of the parking brake when operating the service brake.  
           [0005]    Conventional golf car assemblies are typically floor mounted and extend underneath the car. As a result, conventional assemblies are exposed to a corrosion environment caused by fertilizers and herbicides that are applied to golf courses.  
         SUMMARY OF THE INVENTION  
         [0006]    The instant invention solves problems associated with conventional pedal assemblies by providing a pedal assembly having a reduced number of components, greater flexibility in mounting the assembly within the vehicle, improved mode of operation, among other desirable aspects. The inventive pedal assembly comprises a combined service and parking brake system that can be employed alone, or with an accelerator in a pedal assembly, e.g., a modular pedal assembly including related cables.  
           [0007]    While the instant invention includes many aspects, in one aspect of the invention the service and parking brake are applied by using the same pedal lever. The service brake modulates or is used by depressing the brake pedal a defined portion of its entire lever path. The first portion of the pedal path operates the brake as a service brake. When depressed beyond or past the first portion, the brake becomes locked into position and functions as a parking brake. The brake is released by depressing the accelerator.  
           [0008]    In another aspect of the invention, the parking and service brake pedal share a common lever. The end of the pedal lever defines a surface (e.g., a pedal pad) wherein a portion of that surface includes a pedal button. To operate as a service brake, the operator depresses the pedal button while pushing the pedal. This will disengage a torsion lock spring (mounted around a drum or hub upon which the pedal lever rotates as is described below in greater detail), and allow the pedal lever to rotate in either direction thereby permitting the vehicle operator to modulate operation of the service brake. To operate as a park brake, the operator depresses the pedal pad surface outside of the button area. The button will pop-up or protrude upwardly beyond the surface of the pedal thereby providing a visual indication that the brake is operating as a parking brake. When the pedal is pushed without depressing the pedal button (i.e., by depressing the pedal pad outside of the button area), a “free leg” of the torsion spring will tighten against the drum or hub (when the pedal tries to return) thereby causing the pedal to hold in its applied position.  
           [0009]    In a further aspect of the invention, the parking and service brake are mounted on separate levers such that the service brake lever can be applied separately from the parking brake lever. When both levers are depressed the assembly functions as a service brake and when the parking brake lever is applied separately the assembly functions as a parking brake. The parking brake can be released by depressing the service brake pedal, or the accelerator pedal. The dual pedal service/parking brake system can be adapted for mounting either under a dash or upon a vehicular floor. Since this aspect employs dual brake levers, the pedal pads can possess a wide range of configurations. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    FIGS.  1 - 7  illustrate one aspect of the invention having a pedal assembly comprising separate parking and service brake pedals.  
         [0011]    [0011]FIG. 1 illustrates the pedal assembly in an assembled format.  
         [0012]    [0012]FIG. 2 illustrates the pedal assembly in an exploded format.  
         [0013]    [0013]FIGS. 3 and 4 illustrate a parking brake hub that is employed in one aspect of the invention.  
         [0014]    [0014]FIG. 5 illustrates a service brake hub that is employed in one aspect of the invention.  
         [0015]    [0015]FIG. 6 illustrates a release lever that is employed in one aspect of the invention.  
         [0016]    [0016]FIG. 7 illustrates another aspect of the invention illustrated in FIGS.  1 - 6  that is mounted under-dash or in a suspended design.  
         [0017]    FIGS.  8 - 11  illustrate another aspect of the invention including a remote button for actuating the parking brake system.  
         [0018]    [0018]FIG. 8 illustrates a second aspect of the invention in an assembled format.  
         [0019]    [0019]FIG. 9 illustrates the aspect in FIG. 8 in an exploded format.  
         [0020]    [0020]FIG. 10 illustrates the torsion spring and release rod employed in this aspect of the invention.  
         [0021]    [0021]FIG. 11 illustrates the release rod interconnection to the remote button. 
     
    
     DETAILED DESCRIPTION  
       [0022]    The inventive pedal assembly comprises a service and parking brake and in some cases an accelerator. In comparison to conventional pedal assemblies, the inventive assembly has a reduced number of parts, expeditious assembly, longer life due to improved corrosion protection, improved mode of operation (especially in the case of emergency brake application), among other desirable aspects.  
         [0023]    Any suitable mechanical or electronic accelerator can be employed as a component of the assembly or separately connected to the vehicle. While any suitable electronic accelerator can be employed, examples of suitable accelerators are disclosed in U.S. Pat. Nos. 4,976,166; 5,241,936; 5,697,260 and 5,964,125; the disclosure of each of which is hereby incorporated by reference.  
         [0024]    In one aspect of the invention, the service/parking brake pedal are employed by actuating a single lever. When the pedal is depressed by the vehicle operator, in a first stage (or service brake mode) of operation a force is applied to a cable system that in turn engages the brakes, e.g, associated with the rear wheels. Typically, about 30 to about 45 pounds of force are required to engage the service brake. In its second stage of operation, the pedal is depressed further (towards the vehicle floor) or passed its service brake mode and compresses a torsion spring thereby engaging a parking brake. The amount of force to engage the parking brake is relatively large in comparison to operation of the service brake, e.g., about 60 to about 65 pounds. Upon engaging the parking brake, the pedal will lock into a fixed position. The parking brake is released by depressing the accelerator.  
         [0025]    The locking mechanism for engaging the parking brake mode of operation comprises a hub about which the brake pedal lever rotates. When the brake pedal is engaged as a parking brake, a one way torsion spring that is mounted about the hub applies a torsional or frictional force about the hub that locks the lever into the parking brake mode. During normal or service brake mode, the torsion spring is disengaged by a trigger assembly, e.g., a spring loaded trigger assembly. When the brake is operated as a parking brake, the trigger assembly is rotated by the pedal lever in such a manner as to allow the torsion spring to hold the hub securely against rotation. Depressing the accelerator pulls a linkage, e.g., rod, cable, etc., that causes the trigger assembly to return or disengage the torsion spring thereby returning the brake to a service mode.  
         [0026]    In another aspect of the invention, the brake pedal includes a region defining a pedal button. The pedal button extends upwardly through the surface of the pedal when operating as a parking brake. While the service and parking brake are engaged by movement of the same lever, the parking brake is applied by depressing the pedal without contacting the pedal button. When the pedal is pushed without depressing the pedal button, the “free leg” of the previously described torsion spring will tighten against the hub or drum when the pedal tries to return, therefore causing the pedal to hold in its applied position. To operate as a service brake, the operator simply depresses the pedal button while pushing the pedal. This will disable a torsion spring and allow the pedal to rotate in either direction.  
         [0027]    The force generated when applying the brake pedal is transmitted to a braking system. The brake pedal is connected to a braking system in accordance with conventional means. Typically, the pedal is functionally connected to at least one cable that transfers a force from the pedal to the braking system thereby operating the brake. An example of a suitable cable comprises a steel strand that is coated with a suitable corrosion resistant coating such as TPR (coated cables and strand are available from Orscheln Products LLC, Moberly, Miss.). In order to reduce corrosion, fasteners, cable end-fittings, among other metallic components can be coated with yellow chromate, zinc, polymeric materials, among other corrosion resistant coatings.  
         [0028]    Certain aspects of the invention are better understood by reference to the drawings. These drawings are provided to illustrate certain aspects of the invention and not limit the scope of the invention as defined by appended claims.  
         [0029]    Referring now to FIGS.  1 - 7 , these Figures illustrate a service/parking brake assembly wherein the parking and service brake pedals are mounted on separate levers. The service brake pedal is normally biased in a position relatively close to the vehicle operator. The parking and service brake pedals are, however, mounted on their respective levers in a manner that permits simultaneous depression of both pedals. FIGS. 1 and 2 illustrate parking brake pedal and lever  1 , and service brake pedal and lever  2 . Parking brake pedal  1  is rotatably mounted upon shaft  3  having hub lock  4 . Shaft  3  penetrates parking brake drive hub  5  and service brake drive hub  6 . Parking brake pedal lever  1  is mounted upon drive hub  5  that is in turn mounted upon shaft  3 . Service brake pedal lever  2  is mounted upon drive hub  6  that is in turn mounted upon shaft  3 . Hubs  5  and  6  permit levers  1  and  2  to rotate about shaft  3  together or separately. Parking brake drive hub  5  and hub lock  4  are functionally connected with anchor plate  7 . Anchor plate defines a protuberance  7 A having an opening  7 B into which leg  8 A of torsion spring  8  is attached. Torsion spring  8  is mounted about hub lock  4  such that, when compressed, torsion spring  8  locks parking brake pedal lever  1  into a fixed position. Release lever  9  is mounted on the distal end of brake pedal lever  1  (from the pedal pad surface) in a manner such that the release lever  9  can contact leg  8 A. Torsion spring  8  is de-compressed or released by activation of release lever  9 , pivoting release lever  9  about pin  10  and release lever return spring  11 . A downwardly extending tab or protuberance  2 A on pedal lever  2  engages release lever  9  thereby causing torsion spring  8  to disengage and permitting parking brake pedal lever  1  to move and release the parking brake.  
         [0030]    Pin  12  and clevis  13  mount cable clevis  15  and cable assembly  16  onto parking brake pedal level  1 . Depression (or movement towards the floor) of pedal  1  applies a tension force upon cable assembly  16  thereby engaging the parking brake. By depressing only pedal  1  in order to engage the parking brake, pedal  1  rotates about shaft  3 , engages bumper mechanism  17  (at least one and typically two slots or grooves defined) on hub  5  and applies a tension upon torsion spring  8  that maintains pedal  1  in a locked position. Release (return to normal position) of the parking brake pedal disengages bumper mechanism  17  and torsion spring  8 . Parking brake pedal  1  can be released by either applying a force upon service brake pedal  2  or the accelerator pedal (not shown in FIGS. 1 and 2). The accelerator pedal can either indirectly or directly contact release lever  9 .  
         [0031]    When the parking brake pedal lever is released (as previously described) a spring  14  applies a bias that forces parking brake pedal lever into an operational or service brake position. Spring  14  applies a bias to hub  6  that defines at least one and typically two protuberances  6 A that engage bumper mechanism  17 . That is, spring  14  causes hub  6  to rotate forward (towards the operator) about shaft  3  such that the degree of rotation to defined by the travel of tabs  6 A within bumper mechanism  17 . When pedal  2  is contacted, hub  6  rotates and tabs  6 A move along bumper mechanism  17  until the maximum travel within mechanism  17  is reached after which pedals  1  and  2  can move together. When only pedal  1  is contacted, pedal  1  rotates forward (engages torsion spring  8 ) causes hub  5  to rotate and engage tabs  6 A on hub  6  thereby causing pedal  2  to travel along with and spaced apart from pedal  1 . The torsion spring is released by depressing pedal  2  in the manner described above.  
         [0032]    Referring now to FIG. 7, FIG. 7 is another aspect of FIGS.  1 - 6  with the exception that assembly shown in FIG. 7 is oriented for mounting underneath a dash board. Similar to the above discussion, pedal  2  is biased in a forward position (or toward the operator). Clevis  15  and cable  16  are actuated in response to movement of pedal  1 .  
         [0033]    Referring now to FIGS.  8 - 11 , these Figures illustrate a second aspect of the invention wherein a torsion lock service/parking brake system has a button for parking brake activation. The button  20  is located upon the surface of the brake pedal pad  21  on brake lever  22  and can easily be depressed when depressing the brake pedal. The second aspect of the invention has the same basic components and function as the first aspect, except the second aspect has a remote button  20  to control application mode. That is, application of a torsion spring  23  for defining service versus park brake operation. To operate as a service brake, the operator simply depresses the pedal button  20  while pushing the pedal  21 . This will operate a second lever  24  that contacts leg  23 A and disengage torsion lock spring  23  that is mounted around a shaft  25  (about which the pedal lever  22  rotates), and allow the pedal to rotate in either direction thereby permitting the vehicle operator to modulate operation of the service brake. To operate as a park brake, the operator depress the pedal pad  21  outside of (or without contacting) the button area  20 . The button  20  will pop-up or protrudes upwardly beyond the surface of the pedal pad  21  thereby providing a visual indication that the brake is operating as a parking brake. When the pedal lever  22  is pushed without depressing the pedal button  20 , the “free leg”  23 B of the torsion spring  23  will tighten against the drum when the pedal lever  22  tries to return, therefore causing the pedal lever  22  to hold in its applied position.  
         [0034]    Referring now to FIG. 10, FIG. 10 shows the second lever  24  contacting leg  23 A of the torsion spring  23 . When the parking brake button  20  is depressed along with the brake pedal pad  21 , the second lever  24  disengages the torsion spring  23  from shaft  25  thereby permitting the pedal or brake lever  22  to rotate about shaft  25 . That is, when the button  20  is depressed, leg  23 A of torsion spring  23  is pulled thus causing the torsion spring  23  to disengage from shaft  25  thereby allowing rotation of lever  22  in either direction. When the parking brake button  20  is not depressed along with the brake pedal pad  21 , the second lever  24  engages the torsion spring  23  thereby biasing the spring and generating a frictional force and eventually preventing rotation of the brake lever about the drum.  
         [0035]    Referring now to FIG. 11, FIG. 11 illustrate a cam pin  26  located on a distal end of the second lever that contacts a cam surface  27  on an underneath portion of the parking brake button  20 . When the button  20  is not depressed, a camming action between button  20  and lever  24  causes button  20  to extend upwardly or beyond the surface of pedal pad  21 .  
         [0036]    The components of the inventive pedal assembly can be fabricated from conventional materials in accordance with processes known in this art. For example, stamped steel, sintered metal, die cast zinc or aluminum, mineral filled nylon, among other conventional materials can be employed for fabricating pedal components.