초록 ▼

A compression release brake system 10 includes a hydraulic apparatus 12 for controllably opening at least one exhaust valve 14 of at least one cylinder 16 of an engine in response to motion of a cam actuator 12. The system 10 includes a master piston assembly 40 having a master piston 42 engageable

A compression release brake system 10 includes a hydraulic apparatus 12 for controllably opening at least one exhaust valve 14 of at least one cylinder 16 of an engine in response to motion of a cam actuator 12. The system 10 includes a master piston assembly 40 having a master piston 42 engageable with the cam actuator 12. The master piston 42 includes a compressible piston pin 56. A slave piston assembly 44 is hydraulically linked to the master piston assembly 40 and includes a slave piston 46 engageable with the at least one exhaust valve 14.

대표청구항 ▼

1. A compression release brake system having a hydraulic apparatus for controllably opening at least one exhaust valve of at least one cylinder of an engine in response to motion of a cam actuator, comprising:a master piston assembly having a master piston engageable with said cam actuator, said mas

1. A compression release brake system having a hydraulic apparatus for controllably opening at least one exhaust valve of at least one cylinder of an engine in response to motion of a cam actuator, comprising:a master piston assembly having a master piston engageable with said cam actuator, said master piston including a compressible piston pin; and a slave piston assembly hydraulically linked to said master piston assembly and having a slave piston engageable with said at least one exhaust valve. 2. A compression release brake system, as set forth in claim 1, including a travel-limiting piston assembly positioned to controllably limit linear movement of said master piston within said master piston assembly to a predetermined amount.3. A compression release brake system, as set forth in claim 2, wherein said compressible piston pin is adapted to absorb motion induced by said cam actuator which exceeds that necessary to move said master piston said predetermined amount.4. A compression release brake system, as set forth in claim 3, including a brake control valve controllably connectable to a hydraulic fluid supply, a hydraulic fluid drain, and to each of said master, slave, and travel-limiting piston assemblies, said brake control valve being moveable between a power position at which said master, slave, and travel-limiting piston assemblies are connected to said hydraulic fluid drain, and a brake position at which said master, slave, and travel-limiting piston assemblies are connected to said hydraulic fluid supply.5. A compression release brake system, as set forth in claim 3, wherein said master piston assembly includes:a piston housing having a bore, said master piston being slidably disposed in said piston housing bore; said compressible piston pin having a compressible portion, a solid portion, and a bore extending through said compressible portion into said solid portion; and a guide pin slidably disposed in said piston pin bore and having an end portion engageable with said cam actuator and being adapted to controllably move said master piston within said piston housing bore in response to motion of said cam actuator. 6. A compression release brake system, as set forth in claim 5, wherein said master piston includes a pin receiving portion, and said master piston assembly further includes a piston spring arranged between said piston housing and said piston pin solid portion and adapted to urge said piston pin solid portion into abutting arrangement with said piston body pin receiving portion.7. A method for limiting travel of at least one exhaust valve of at least one cylinder of an engine during a compression release brake event, said engine having a cam actuator, a master piston assembly having a master piston, said master piston including a compressible piston pin and a guide pin, said guide pin being engageable with said cam actuator, a slave piston assembly hydraulically linked to said master piston assembly and having a slave piston engageable with said at least one exhaust valve, and a travel-limiting piston assembly having a travel-limiting piston positioned to controllably limit movement of said master piston, comprising the steps of:moving said travel-limiting piston to a position sufficient to limit movement of said master piston to a predetermined amount; moving said master piston said predetermined amount in response to said cam actuator acting upon said guide pin, and responsively opening said at least one exhaust valve a predetermined amount; and compressing said compressible piston pin in response to further action of said cam actuator upon said guide pin beyond that required to move said master piston said predetermined distance.