초록 ▼

The invention relates to a brake system configured to enhance control and maneuverability of a three-wheeled agricultural applicator. The brake system includes a brake pedal in fluid communication with a rear brake system and a front brake system. The front brake system includes a flow limiter in co

The invention relates to a brake system configured to enhance control and maneuverability of a three-wheeled agricultural applicator. The brake system includes a brake pedal in fluid communication with a rear brake system and a front brake system. The front brake system includes a flow limiter in communication with a brake actuator configured to delay application of a second braking force by the front brake system relative to application of a first braking force by the rear brake system. The front brake system includes a front brake mechanism comprising a caliper assembly in combination with a disc brake configured to apply the second braking force to the at least one front wheel assembly. The caliper assembly employs a spacer combined with a series of bushings to float the caliper assembly in general alignment with movement of the disc brake caused by dynamic forces associated with operation of the vehicle.

대표청구항 ▼

We claim: 1. A vehicle, comprising: a drive unit; a cab; a chassis assembly in support of the cab and the drive unit, the chassis assembly including at least one front wheel assembly and a pair of rear wheel assemblies, the drive unit configured to drive the pair of rear wheel assemblies; and a bra

We claim: 1. A vehicle, comprising: a drive unit; a cab; a chassis assembly in support of the cab and the drive unit, the chassis assembly including at least one front wheel assembly and a pair of rear wheel assemblies, the drive unit configured to drive the pair of rear wheel assemblies; and a brake system, the brake system comprising: a brake pedal disposed in the cab, the brake pedal configured to be actuated by an operator to engage the brake system; a rear brake system configured to apply a first braking force to the pair of rear wheel assemblies in response to actuation of the brake pedal, the rear brake system being pneumatically-driven; and a front brake system configured to apply a second braking force to the at least one front wheel assembly in response to actuation of the brake pedal, the front brake system being hydraulically-driven, the front brake system including a flow limiter configured to cause the second braking force to be applied to the front wheel assembly subsequent to application of the first braking force by the rear brake system to the pair of rear wheel assemblies. 2. The vehicle as recited in claim 1, wherein actuation of the brake pedal releases a fluid flow to the front and rear brake systems, wherein the at least one front wheel assembly includes a front wheel mounted on a front shaft, and wherein the front brake system further comprises: a hydraulic source configured to provide a hydraulic flow; a disc brake coupled to the front wheel; a caliper assembly operable to engage the disc brake; and a brake actuator in communication with the hydraulic source, the brake actuator operable to provide the hydraulic flow to the caliper assembly, wherein in response to the hydraulic flow from the brake actuator, the caliper assembly in combination with the disc brake applies the second braking force to the at least one front wheel assembly. 3. The vehicle as recited in claim 2, wherein the second braking force applied by the caliper assembly and the disc brake to the at least one front wheel assembly is approximately 100,000 inch-pounds of deceleration torque. 4. The vehicle as recited in claim 2, further including at least one front fork assembly configured to support the at least one front wheel assembly and associated front brake mechanism, the front fork assembly comprising: a fork mounted on the front shaft, the disc brake coupled between the front wheel and the fork; and a reinforcement plate connected to the fork, the caliper assembly mounted on the reinforcement plate. 5. The vehicle as recited in claim 4, wherein the disc brake is fixed to the front wheel, the disc brake including an inner portion and an outer portion, the inner portion being recessed relative to the outer portion, and wherein the outer portion of the disc brake is spaced apart from the front wheel along the front shaft and configured to be engaged by the caliper assembly. 6. The vehicle as recited in claim 4, wherein the caliper assembly further comprises: a first caliper and a second caliper, the first caliper disposed opposite the second caliper with the disc brake disposed therebetween, the first and second calipers each including a brake pad configured to engage the disc brake in response to the hydraulic flow from the brake actuator; a spacer coupled between the first and second calipers, the spacer including a first opening and second opening each disposed at opposed ends of the spacer and outside the first and second calipers; a first bushing and a second bushing disposed in the first and second openings, respectively; and a first shaft and a second shaft inserted through the first and second bushings, respectively, the first and second shafts each coupled to the reinforcement plate, wherein the first and second calipers and the spacer therebetween float on the first and second bushings in general alignment with the disc brake in response to deflection in the front shaft of the at least one front wheel assembly. 7. A brake system for a vehicle having at least one front wheel assembly and at least one rear wheel assembly the brake system including a brake pedal configured such that actuation of the brake pedal causes engagement of the brake system, the brake system comprising: a rear brake system configured to apply a first braking force to the at least one rear wheel assembly in response to actuation of the brake pedal; and a front brake system configured to apply a second braking force to the at least one front wheel assembly in response to actuation of the brake pedal, the front brake system including a flow limiter operable to cause application of the second braking force to the at least one front wheel assembly subsequent to application of the first braking force by the rear brake system to the at least one rear wheel assembly, wherein the caliper assembly comprises: a first caliper having a first housing portion and a first brake pad; a second caliper having a second housing portion and a second brake pad, the second brake pad opposed to the first brake pad with the disc brake disposed therebetween; a spacer removably disposed between the first and second calipers, the spacer having a first and a second opening each disposed at opposed ends of the spacer and radially outward relative to the first and second housing portions of the first and second calipers, respectively; a first and a second bushing inserted in the first and second openings, respectively, in the spacer; and a first and a second shaft each having a first end and a second end, the first ends of the first and second shafts connected to a fork assembly, the first and second shafts extending through the first and second bushings in the first and second openings of the spacer, respectively, wherein the caliper assembly floats on the first and second bushings in general alignment with the disc brake in response to deflection in the front shaft of the at least one front wheel assembly. 8. The brake system as recited in claim 7, wherein the disc brake is connected to the front wheel of the at least one front wheel assembly, the disc brake being spaced apart from the front wheel of the at least one front wheel assembly, and wherein the caliper assembly is mounted on the front fork assembly. 9. The vehicle as recited in claim 7, wherein the disc brake includes an inner portion and an outer portion, the inner portion being recessed a predetermined distance relative to the outer portion, the inner portion being fixed adjacent to the front wheel, and the outer portion of the disc brake being spaced apart from the front wheel along the front shaft of the at least one front wheel assembly, and wherein the caliper assembly engages the outer portion of the disc brake to apply the second braking force to the at least one front wheel assembly. 10. A method of braking a vehicle, the vehicle including at least one front wheel assembly and at least one rear wheel assembly, the vehicle further including a brake system having a brake pedal configured to release a fluid flow to a rear brake system and a front brake system, the method comprising the steps of: actuating the brake pedal; transmitting a fluid flow to the front and rear brake systems in response to actuation of the brake pedal; applying a first braking force by the rear brake system to the at least one rear wheel assembly in response to the fluid flow; limiting the fluid flow to the front brake system; and applying a second braking force by the front brake system to the at least one front wheel assembly in response to the fluid flow, wherein applying the second braking force occurs subsequent to applying the first braking force by the rear brake system to the at least one rear wheel assembly, wherein the rear brake system is pneumatically-driven and the front brake system is hydraulically-driven, and wherein the transmitted fluid flow to the front and rear brake systems is a pneumatic flow, the front brake system comprising: a brake actuator in combination with a hydraulic source to regulate a hydraulic flow to a front brake mechanism, wherein the step of limiting the fluid flow to front brake system includes limiting the pneumatic flow to the brake actuator. 11. The method as recited in claim 10, wherein the first braking force applied by the rear brake system to the at least one rear wheel assembly is less than the second braking force applied by the front brake system to the at least one front wheel assembly. 12. The method as recited in claim 10, wherein the front brake mechanism further comprises a caliper assembly in combination with a disc brake operable to provide the second braking force to the at least one front wheel assembly, the step of applying the second braking force by the front brake system comprising: activating the brake actuator in response to the pneumatic flow; transmitting the hydraulic flow from the brake actuator to the front brake mechanism; engaging the caliper assembly against the disc brake in response to the hydraulic flow from the hydraulic source; and exerting a braking torque on the at least one front wheel assembly. 13. A brake system for a vehicle having at least one front wheel assembly and at least one rear wheel assembly, the brake system including a brake pedal configured such that actuation of the brake pedal causes engagement of the brake system, the brake system comprising: a rear brake system configured to apply a first braking force to the at least one rear wheel assembly in response to actuation of the brake pedal; and a front brake system configured to apply a second braking force to the at least one front wheel assembly in response to actuation of the brake pedal, the front brake system comprising: a flow limiter operable to cause application of the second braking force to the at least one front wheel assembly subsequent to application of the first braking force by the rear brake system to the at least one rear wheel assembly, wherein actuation of the brake pedal releases a fluid flow to the front and rear brake systems, a hydraulic fluid source configured to provide a hydraulic flow, a front brake mechanism connected to receive the hydraulic flow from the hydraulic source, and a brake actuator in communication with the hydraulic fluid source, the brake actuator connected to receive the fluid flow associated with actuation of the brake pedal, the brake actuator operable to regulate the hydraulic fluid flow to the front brake mechanism, wherein the rear brake system is pneumatically-driven, and wherein the front brake system is hydraulically-driven, wherein in response to a build-up of a predetermined fluid flow to the brake actuator, and wherein the brake actuator provides the hydraulic flow to reach the front brake mechanism so as to cause the front brake mechanism to apply the second braking force to the at least one front wheel assembly. 14. The brake system as recited in claim 13, wherein the vehicle includes a fork assembly in support of the front wheel assembly and the front brake system, wherein the front wheel assembly includes a front wheel mounted on a front shaft, and wherein the front brake system further comprises: a disc brake fixed to rotate with the front wheel of the at least one front wheel assembly; and a caliper assembly associated with the disc brake, the caliper assembly and the disc brake configured to apply the second braking force to the at least one front wheel assembly. 15. The brake system as recited in claim 13, wherein application of the second braking force by the front brake system to the at least one front wheel assembly occurs following a predetermined time delay relative to when application of the first braking force by the rear brake system to the at least one rear wheel assembly occurs. 16. The brake system as recited claim 15, further comprising a flow limiter disposed upstream of the brake actuator, and wherein the flow limiter is configured to create the predetermined time delay by limiting the fluid flow rate to the brake actuator. 17. The brake system as recited in claim 16, wherein the flow limiter comprises: an inlet in communication with a first passage configured to receive the fluid flow associated with actuation of the brake pedal, the inlet and first passage having a first cross-sectional area; a second passage aligned and in communication with the first passage, the second passage having a second cross-sectional area; and an outlet in communication the second passage, the outlet having a third cross-9 sectional area, wherein the first cross-sectional area of the inlet and the first passage is larger relative to the second cross-sectional area of the second passage, and wherein the second cross-12 sectional area of the second passage is larger relative to the third cross-sectional area of the outlet. 18. A brake system for a wheel assembly rotatable about a shaft, comprising: a caliper assembly configured to engage a disc brake so as to apply a braking force to the wheel assembly, the caliper assembly comprising: a first caliper and a second caliper each including a brake pad configured to engage the disc brake; a spacer removably disposed between the first and second calipers, the spacer including a first opening and a second opening each disposed at opposed ends of the spacer; a first and a second bushing disposed in the first and the second openings, respectively, of the spacer; and a first and a second shaft inserted through the first and second bushings, respectively, wherein the first and second calipers and spacer therebetween float on the first and second bushings in general alignment with the disc brake in response to deflection in the shaft of the wheel assembly. 19. The brake system of claim 18, wherein the shaft of the wheel assembly is supported on a fork assembly of a vehicle, and wherein the first and second shafts of the calliper assembly each include a first end attached at the fork assembly.