Method and apparatus for suspending a vehicle

Abstract

A suspension for, and a method for suspending, a vehicle having a body is provided. The suspension includes a first suspension assembly and a second suspension assembly. The first suspension assembly extends between a first surface contact assembly and the body, and the second suspension assembly extends between a second surface contact assembly and the body. The first and second suspension assemblies each have a tranverse instant center. The first suspension assembly and the second suspension assembly are aligned so that a vertical centerline of each surface contact assembly lies within a transverse vertical plane that extends therebetween. The tranverse instant center of each suspension assembly is located within the tranverse vertical plane, below a roll center located within the tranverse vertical plane.

What is claimed is:  
     
         1 . A suspension for a vehicle having a body, the suspension comprising: 
 a first suspension assembly that extends between a first surface contact assembly and the body, wherein the first suspension assembly includes a transverse instant center;    a second suspension assembly that extends between a second surface contact assembly and the body, wherein the second suspension assembly includes a transverse instant center;    wherein the first suspension assembly and the second suspension assembly are aligned so that a vertical centerline of each surface contact assembly lies within a transverse vertical plane that extends therebetween; and    wherein the transverse instant center of each suspension assembly is located within the transverse vertical plane, below a roll center located within the transverse vertical plane.    
     
     
         2 . The suspension of  claim 1 , wherein the first suspension assembly and the second suspension assembly each comprise: 
 a first support arm having a first spindle mount and a pair of first body mounts, wherein a first support arm plane is defined by the first spindle mount and the first body mounts;    a second support arm having a second spindle mount and a pair of second body mounts, wherein a second support arm plane is defined by the second spindle mount and the second body mounts;    wherein the first support arm and the second support arm are positioned such that the first support arm plane intersects the transverse vertical plane along a first line, and the second support arm plane intersects the transverse vertical plane along a second line, and the first line and second line cross each other at the transverse instant center.    
     
     
         3 . The suspension of  claim 2 , wherein each suspension assembly supports a surface member that has a contact patch with a center, and wherein the roll center is located within the transverse vertical plane at an intersection of a third line and a fourth line; 
 wherein the third line extends through the center of the contact patch of the surface member supported by the first suspension assembly and the transverse instant center of the first suspension assembly; and    wherein the fourth line extends through the center of the contact patch of the surface member supported by the second suspension assembly and the transverse instant center of the second suspension assembly.    
     
     
         4 . The suspension of  claim 3 , wherein the first support arm comprises: 
 a first member that extends between the first spindle mount and one of the first body mounts; and    a second member that extends between the first spindle mount and the other of the first body mounts.    
     
     
         5 . The suspension of  claim 4 , wherein the first support arm further comprises a lateral member extending between the first member and the second member.  
     
     
         6 . The suspension of  claim 4 , wherein the second support arm comprises: 
 a first member that extends between the second spindle mount and one of the second body mounts; and    a second member that extends between the second spindle mount and the other of the second body mounts.    
     
     
         7 . The suspension of  claim 6 , wherein the second support arm further comprises a lateral member extending between the first member and the second member.  
     
     
         8 . The suspension of  claim 2 , wherein the first support arm plane intersects a longitudinally extending plane that passes through a centerline of a surface member supported by the first suspension assembly along a third line; and 
 wherein the second support arm plane intersects the longitudinally extending plane along a fourth line; and    wherein the third and fourth lines are skewed and converge at a point located within the longitudinally extending plane.    
     
     
         9 . The suspension of  claim 2 , wherein a first body mount line extends through the pair of first body mounts and a second body mount line extends through the pair of second body mounts; and 
 wherein the first body mounts are attached to the body such that the first body mount line is skewed by a first angle from a longitudinally extending centerline of the vehicle.    
     
     
         10 . The suspension of  claim 9 , wherein the second body mounts are attached to the body such that the second body mount line is skewed by a second angle from the longitudinally extending centerline of the vehicle.  
     
     
         11 . The suspension of  claim 10 , wherein the first angle and the second angle are equal.  
     
     
         12 . The suspension of  claim 2 , wherein a first surface contact assembly mount line extends through the first spindle mount and the second spindle mount within the first suspension assembly, and a second surface contact assembly mount line extends through the first spindle mount and the second spindle mount within the second suspension assembly; 
 wherein at least one of the first wheel assembly mount line and the second wheel assembly mount line is skewed from a vertical centerline of a surface member attached to the respective first wheel assembly and second wheel assembly.    
     
     
         13 . The suspension of  claim 2 , wherein the first contact assembly and the second contact assembly are ski mount assemblies.  
     
     
         14 . The suspension of  claim 2 , wherein the first contact assembly and the second contact assembly are wheel mount assemblies.  
     
     
         15 . The suspension of  claim 2 , wherein the first contact assembly and the second contact assembly are roller mount assemblies for use with an endless track.  
     
     
         16 . The suspension of  claim 2 , wherein the first contact assembly and the second contact assembly are wheel mount assemblies adapted for use on a rail.  
     
     
         17 . A suspension for a surface contact assembly of a vehicle having a body, the suspension comprising: 
 a first support arm having a first spindle mount and a pair of first body mounts, and a first support arm plane defined by the first spindle mount and the first body mounts;    a second support arm having a second spindle mount and a pair of second body mounts, and a second support arm plane defined by the second spindle mount and the second body mounts;    wherein the first spindle mount is pivotally attached to the surface contact assembly at an upper spindle joint, and the second spindle mount is pivotally attached to the surface contact assembly at a lower spindle joint, and the first body mounts are pivotally attached to the body at a pair of lower body points, and the second body mounts are attached to the body at a pair of upper body points, and the first support arm and the second support arm thereby cross each other.    
     
     
         18 . The suspension of  claim 17 , wherein the first support arm plane intersects a transversely extending plane that passes through a centerline of a surface member supported by the surface contact assembly along a first line; and 
 wherein the second support arm plane intersects the transversely extending plane along a second line; and    wherein the first and second lines are skewed and converge at a point located within the tranversely extending plane.    
     
     
         19 . The suspension of  claim 17 , wherein a first body mount line extends through the pair of first body mounts and a second body mount line extends through the pair of second body mounts; and 
 wherein the first body mounts are attached to the body such that the first body mount line is skewed by a first angle from a longitudinally extending centerline of the vehicle.    
     
     
         20 . The suspension of  claim 19 , wherein the second body mounts are attached to the body such that the second body mount line is skewed by a second angle from the longitudinally extending centerline of the vehicle.  
     
     
         21 . The suspension of  claim 20 , wherein the first angle and the second angle are equal.  
     
     
         22 . The suspension of  claim 17 , wherein a surface contact assembly mount line extends through the first spindle mount and the second spindle mount; 
 wherein the surface contact assembly mount line is skewed from a vertical centerline of a surface member attached to the surface contact assembly.    
     
     
         23 . The suspension of  claim 17 , wherein the first suspension assembly and the second suspension assembly each further comprise: 
 a spring assembly having a first end pivotally attached to one of the first support arm or the second support arm, and a second end pivotally attached to the body;    wherein each spring assembly provides a diminishing load rate to the surface contact assembly as the spring assembly is compressed.    
     
     
         24 . A method for suspending a vehicle having a body, comprising the steps of: 
 providing a first suspension assembly that extends between a first surface contact assembly and the body, wherein the first suspension assembly includes a transverse instant center;    providing a second suspension assembly that extends between a second surface contact assembly and the body, wherein the second suspension assembly includes a transverse instant center;    aligning the first surface contact assembly and the second surface contact assembly so that a vertical centerline of each surface contact assembly lies within a transverse vertical plane that extends therebetween;    positioning the first suspension assembly and the second suspension assembly so that the transverse instant center of each suspension assembly is located within the transverse vertical plane, vertically below a roll center located within the transverse vertical plane.    
     
     
         25 . The method of  claim 24 , wherein the first suspension assembly and the second suspension assembly each comprise: 
 a first support arm having a first spindle mount and a pair of first body mounts, wherein a first support arm plane is defined by the first spindle mount and the first body mounts;    a second support arm having a second spindle mount and a pair of second body mounts, wherein a second support arm plane is defined by the second spindle mount and the second body mounts;    wherein the first support arm and the second support arm are positioned such that the first support arm plane intersects the transversevertical plane along a first line, and the second support arm plane intersects the transverse vertical plane along a second line, and the first line and second line cross each other at the transverse instant center.    
     
     
         26 . The method of  claim 25 , further comprising the steps of: 
 providing a surface member on each suspension assembly, wherein the surface member has a contact patch with a center, and wherein the roll center is located within the transverse vertical plane at an intersection of a third line and a fourth line;    wherein the third line extends through the center of the ground contact patch of the surface member supported by the first ground contact assembly and the transverse instant center of the first suspension assembly; and    wherein the fourth line extends through the center of the contact patch of the surface member supported by the second ground contact assembly and the transverse instant center of the second suspension assembly.    
     
     
         27 . The method of  claim 24 , further comprising: 
 wherein the first support arm plane intersects a longitudinally extending plane that passes through a centerline of a surface member supported by the first surface contact assembly along a third line, and the second support arm plane intersects the longitudinally extending plane along a fourth line; and    skewing the first support arm and the second support arm so that the third and fourth lines converge at a point located within the longitudinally extending plane.    
     
     
         28 . The method of  claim 24 , further comprising: 
 wherein a first body mount line extends through the pair of first body mounts and a second body mount line extends through the pair of second body mounts; and    attaching the first body mounts to the body such that the first body mount line is skewed by a first angle from a longitudinally extending centerline of the vehicle.    
     
     
         29 . The method of  claim 28 , further comprising the step of: 
 attaching the second body mounts to the body such that the second body mount line is skewed by a second angle from the longitudinally extending centerline of the vehicle.    
     
     
         30 . The method of  claim 24 , further comprising: 
 wherein a first ground contact assembly mount line extends through the first spindle mount and the second spindle mount of the first suspension assembly, and a second ground contact assembly mount line extends through the first spindle mount and the second spindle mount of the second suspension assembly;    skewing at least one of the first ground contact assembly mount line and the second ground contact assembly mount line from a vertical centerline of a surface member attached to the respective first ground contact assembly and second ground contact assembly.    
     
     
         31 . A suspension for an axle assembly of a vehicle having a body, the suspension comprising: 
 one or more first support arms each having a first mount disposed on a first end of the first support arm, and a second mount disposed on a second end of the first support arm;    one or more second support arms each having a first mount disposed on a first end of the second support arm and a second mount disposed on a second end of the second support arm;    wherein the first mount of each of the first support arms is pivotally attached to the axle assembly at an upper flange joint, and the first mount of each of the second support arms is pivotally attached to the axle assembly at a lower flange joint, and the second mount of each of the first support arms is pivotally attached to the body at a lower body point, and the second mount of each of the second support arms is pivotally attached to the body at an upper flange joint, and the one or more first support arms and the one or more second support arms thereby cross each other.    
     
     
         32 . The suspension of  claim 31 , wherein the suspension further comprises: one or more spring assemblies having a first end pivotally attached to one of the first support arms or the second support arms, and a second end pivotally attached to the body.