Abstract:
A motorcycle brake and suspension system has an outer tube, a mainspring mounted at least partially inside the outer tube. The mainspring has a smaller diameter than the outer tube, a pushrod mounted at least partially inside the mainspring. The pushrod has a smaller diameter than the mainspring. A brake line is mounted at least partially inside the pushrod. The brake line has a smaller diameter than the pushrod.

Description:
This application is a continuation in part of applicant&#39;s integrated motorcycle brake and suspension system Ser. No. 11/062,196 filed Feb. 18, 2005. This application incorporates by reference the disclosure made in the parent application. 
    
    
     DISCUSSION OF RELATED ART 
     Motorcycle brake lines have traditionally been mounted on the outside of the motorcycle fork leg. External brake line mounting provides interaction between the brake line and the external environment. External brake line mounting is therefore not as preferable. Internal brake line can improve a motorcycle fork leg performance. Also, exterior brake line mounting affects the aesthetics of the motorcycle. Aesthetic considerations in motorcycle design predominate in custom motorcycles. Unfortunately in internal brake line configurations, the brake line parts are normally inaccessible and internal to the fork leg, so the brake system must be elegantly designed to avoid mechanical complications. 
     The brake system of a suspension is typically controlled by a brake control that is connected to a fork leg such as the one that is attached to the present invention. A brake control typically known in the art is described in U.S. Pat. No. 5,476,162 entitled forward control for motorcycle rear brakes. The controller operated by a foot in turn operates a chamber that acts upon pressurized fluid. Pressurized fluid enters the suspension brake system and travels through the suspension brake system to operate the brake mounted on the fork leg. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of the hidden brake line device.  FIG. 1  has a cross section notation to  FIG. 3  showing the  FIG. 3  cross section plane. 
         FIG. 2  is and exploded assembly view of the present invention. 
         FIG. 3  is a cross section view of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     As shown in figure one, the inner tube  1  fits within the outside tube  2  and a seal cover  36  keeps debris out of the suspension system. The left and right legs are held by an upper triple clamp  27  and a lower triple clamp  36 . The inside tube  1  slides inside of the outside tube  2  during operation. The telescoping configuration allows dynamic change of fork leg length depending upon the road and travel conditions. The present configuration is typically well-suited for a road bike and is not preferable for off-road operation, although off-road operation is also possible. 
       FIG. 2  shows an exploded view showing assembly of the device where the parts fit together along the axis of the fourth leg. The bottom out spacer  65  is formed as a hollow short tube and retains a brake line loop and connects to the first body cap  13  and second body cap  138 . The brake line loop allows slack so that upon contraction of the telescoping fork leg, the loop expands, and upon expansion of the telescoping fork leg, the loop contracts. Preferably, the loop is oval and greater than a circle at its most contracted position. The body cap secures the upper fork tree  27 , to the inside tube  1 . Each of the fork legs have a body cap, however the body cap that does not have the brake line does not require an opening to allow passage of a brake line. A steering stem  33  connects to the upper fork tree  27  and to the lower fork tree  28 . Caliper bolts  29  retain the inside tube within the clamps. A pair of steering stop pins  30  are disposed within the lower fork tree  28  allowing steering control. To secure the steering stem, steering stem bolt  331  fits within the lower triple clamp  28 . A pair of washers bound the main spring  21  on each side. The bottom washers  8210  fit between the mainspring  21  and the inside tube  1 . A body cap  13 ,  138  has integrally formed a body cap O-ring, and additionally a caliper O-ring  16  to provide a shaft adapter  16 . The shaft adapter O-ring  16  forms a seal. 
     The outside tube  1  has a top out bushing  7  at its lower terminal. The valve snap ring  10 , damper rod piston  6  fits over the top out spring  24 , which fits over the damper rod piston circlip  11 . The directional control valve  8  has a directional control valve spring  9  a pair of circlips  11 . The pair of circlips retains the directional control valve and there is an upper circlip and a lower circlip for each of the left and right legs. Although the circlips can be integrally formed with the directional control valve  8 , standard circlips can be used on the directional control valve for cost considerations. The piston wiper seal fits over the piston seal  4 . A seal snap ring  25  retains the piston seal  4 . Thus, the outside tube is sealed and does not leak oil. The inside tube is also sealed and does not leak oil. 
     The damper bolt line crush washer  664  fits over the damper rod retainer bolt  66 . The damper rod retainer bolt  66  secures to the damper rod, also called the push rod. The push rod also called the damper rod has a dual function in that it facilitates the dampening as well as absorbing shock pushing from the axle. The damper rod retainer bolt  66  has a hollow inside passage receiving hydraulic fluid, and has an outside threaded portion that screws into the damper rod. The banjo bolt  381  has a coupling to the damper rod retainer bolt, and receives hydraulic fluid from the damper rod retainer bolt  66 . The banjo bolt has a hydraulic conduit through its body. The banjo bolt has a hydraulic passage that can go perpendicularly from the face that secures to the damper rod retainer bolt  66 , up via connection members  401  and nut  386 . The banjo bolt should preferably be as seen in the figures having a torus shaped main body communicating with a tube protruding from the main body. The tube extends preferably perpendicular from the main body, out through the slot that the banjo bolt was installed through. Thus, a portion of the banjo bolt preferably sticks out from the fork leg and can be attached to a brake system that is on the brake bracket  31 . In  FIG. 2 , the banjo bolt has a connection line passing through the axle hole of the brake bracket  31 . This does not signify that the banjo bolt is mounted through the axle hole, but rather the drawings place the location of the banjo bolt and connection lines for sake of clarity. It is obvious that the banjo bolt has a banjo bolt slot immediately above the axle hole of the brake bracket  31 . The proper mounting procedure is to put the brake bracket  31  on the out side tube  2 , then pass the banjo bolt through the banjo bolt slot. A wide variety of commercially available brake systems can be mounted to the brake bracket and connected to the terminal of the banjo bolt  381 . 
     A bottom out washer  39  adapts to the bottom out spring  23 . A bottom out spring  23  under the directional control valve  8  provides bottom out support the engagement height of which can be adjusted by main spring height adjustment mechanism  3705  here formed as a spring retainer clip  3705 . Spring retainer clips  3705  fit into grooves of the retainer clip push rods  37 . It is not required that the spring retainer clip  3705  fully surround the push rod  37 . 
     The bottom out spring is activated when the mainspring  21  has exceeded its mechanical limit. 
     The bottom out spring  23  thus has a greater stiffness than the mainspring  21 . The top out spring  24  similarly has a greater stiffness than the mainspring  21  as the top out spring  24  is activated when the mainspring  21  has exceeded its mechanical limit. As with typical mechanical design, the springs preferably rest upon washers for better force distribution. 
     The damper rod retainer bolt has a socket head and allows passage of the pressure in the cable  38  to pass through and connect to the lower portion of the fork leg. At the lower portion of the brake leg, a brake bracket  31  secures onto the lower leg by a bolt. A banjo bolt is typically a bolt having a bore through the main axis that meets at a perpendicular cross bore. The banjo bolt is commonly used in hydraulic applications. The banjo bolt fits inside a slot adapted to receive the banjo bolt. The banjo bolt  381  being hollow connects the brake line inside the fork and passes it to the brake mechanism mounted to the brake bracket  31 . 
     The fender bracket  32  attaches to the lower leg outer tube  2  and is secured by a pair of fender bracket bolts  322 . The fender of the motorcycle is then mounted on the fender bracket. The axle defined the lower portion of the fork leg has a cover  57 . A bearing brake bracket bushing  42  fits within the aperture formed for the axle. 
       FIG. 3  shows brake line sheathing  8201  fitted over the brake line  38  to increase the stiffness of the brake line  38  and protect the brake line  38 . The brake line  38  is adapted to the bolt  66 . A damper bolt line crush washer  6604  fits between the bolt  66  and the banjo bolt  381 . The banjo bolt  381  is secured between a pair of banjo nuts  401  and is tightened by the bottom banjo bolt nut  386 . 
     The brake line  38  has a bottom end and a top end. The bottom end is attached to the bolt  66 , and the line  38  passes through the outer tube  2 , the inner tube  1 , the push rod, the top out springs  24  and bottom out springs  23 , the main spring  21  and the bottom out spacer  65 . The top end passes through the body cap  138  and the upper fork tree  27  until it terminates at the brake actuator. The brake is shown on the right side in  FIG. 2 , but can be on the left side as well. Because most of the parts are symmetrical and interchangeable, the line can be run through either the left or right leg. The brake line is looped to allow slack. The loop is typically kept in the upper portion of the bottom out spacer. The loop is typically well lubricated because oil fills the fork leg. The loop can also be placed in other parts of the fork leg, but the bottom out spacer provides the most radius in the preferred embodiment and is also relatively free of entanglements. Although a single loop is preferable, a double loop can also be implemented. A double loop has the advantage of additional and redundant slack. 
     The vertical force generated, such as when the motorcycle hits a bump is transmitted from the wheel to the axle, and from the axle to the bottom portion of the outer tube  2 , to the push rod, back to the bottom out spacer  65 , then body cap  138 . When the brake line  38  passes through the body cap  138 , the body cap has an O-ring seal preventing escape of fluid from the fork leg. 
     When fully assembled, the directional control valve  FIG. 3 ,  801  allows fluid flow in a single direction. The valve  801  is biased closed by the spring  901  and held within the valve snap ring  1011 . The valve is designed to circulate hydraulic fluid within the fork leg as the opening and closing of valve acts as a pump. The valve is a one-way valve. Preferably, the valve is open on compression and closed on rebound to provide to a variable resistance better ride. The valve can be made so that it has controlled leaking to provide a softer ride. The circlip and push rod is the first embodiment of the adjustable length design. Threading the push rod and providing locking nuts that engage with the push rod can implement a second alternative embodiment of the adjustable length push rod. Threading the push rod is less preferable because length tolerances will not be as precise. 
     Typical materials can be used in construction of the motorcycle fork leg. For example, the body cap can be made of aluminum and the fork leg outer tube can be made of steel and that can receive a chrome finish. Internal components such as washers and springs can be made of spring steel or whatever is known in the art. 
     Although the present invention has been described in detail, persons of ordinary skill in the art understand obvious modifications. Therefore the invention is not intended to be limited except by the following claims. A call out list of elements is provided in the specification for convenience of the reader. The call out list of elements has been designed as a parts list to facilitate understanding of the invention. 
     CALL OUT LIST OF ELEMENTS 
     
         
           1  Inner Tube 
           2  Outer Tube 
           4  Piston Seal 
           6  Damper Rod Piston 
           7  Top Out Bushing 
           8  Directional Control Valve 
           801  Directional Control Valve 
           9  Directional Control Valve Spring 
           901  Directional Control Valve Spring 
           10  Valve Snap Ring 
           1011  Valve Snap Ring 
           11  Directional Control Valve Circlip 
           13  Body Cap 
           16  Caliper O-Ring 
           21  Main Spring 
           23  Bottom Out Spring 
           24  Top Out Spring 
           27  Upper Tree, Triple Clamp Upper 
           28  Lower Tree, Triple Clamp Lower 
           29  Caliper Bolts 
           31  Brake Bracket 
           331  Steering Stem Bolt 
           32  Fender Bracket 
           322  Fender Bracket Bolts 
           36  Seal Cover 
           37  Pushrod For Retainer Clips 
           3705  Spring Retainer Clip 
           38  Brake Line 
           381  Banjo Bolt 
           386  Bottom Banjo Nut 
           39  Bottom Out Washer 
           401  Banjo Nuts 
           42  Brake Bracket Bushing 
           57  Fork Leg Cover 
           65  Bottom Out Spacer 
           66  Damper Rod Retainer Bolt 
           8201  Brake Line Sheathing 
           8210  Bottom Washers