Engine brake apparatus
First Claim
1. A system for transferring engine valve actuation motion between first and second valve train elements, said system comprising:
- an actuator piston bore formed in the second valve train element;
an actuator piston slideably disposed in the actuator piston bore;
a solenoid control valve;
a first hydraulic fluid supply passage connected to the solenoid control valve;
a hydraulic circuit extending between the actuator piston bore and the solenoid control valve;
a solenoid actuated valve disposed in said hydraulic circuit between the solenoid valve and the actuator piston bore;
a means for expanding the volume of the hydraulic circuit during times when the solenoid control valve opens to provide hydraulic fluid from the first hydraulic fluid supply passage to the solenoid actuated valve;
a bypass circuit included in the hydraulic circuit, the bypass circuit extending between the means for expanding and the actuator piston bore, and the bypass circuit extending around the solenoid actuated valve; and
a first check valve disposed in the bypass circuit.
4 Assignments
0 Petitions
Accused Products
Abstract
Apparatus and methods for hydraulic valve actuation of engine valves are disclosed. An exemplary embodiment of the present invention may include a lost motion piston assembly that transfers motion between first and second rocker arms to selectively provide auxiliary engine valve actuation motions to the engine valves for engine operations such as engine braking and exhaust gas recirculation. The lost motion piston assembly may reduce or eliminate transient loads that may otherwise be transmitted to engine valve train elements during the times that lost motions systems are turned on and off for auxiliary valve actuations.
11 Citations
18 Claims
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1. A system for transferring engine valve actuation motion between first and second valve train elements, said system comprising:
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an actuator piston bore formed in the second valve train element; an actuator piston slideably disposed in the actuator piston bore; a solenoid control valve; a first hydraulic fluid supply passage connected to the solenoid control valve; a hydraulic circuit extending between the actuator piston bore and the solenoid control valve; a solenoid actuated valve disposed in said hydraulic circuit between the solenoid valve and the actuator piston bore; a means for expanding the volume of the hydraulic circuit during times when the solenoid control valve opens to provide hydraulic fluid from the first hydraulic fluid supply passage to the solenoid actuated valve; a bypass circuit included in the hydraulic circuit, the bypass circuit extending between the means for expanding and the actuator piston bore, and the bypass circuit extending around the solenoid actuated valve; and a first check valve disposed in the bypass circuit. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A system for transferring engine valve actuation motion between first and second valve train elements, said system comprising:
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an actuator piston bore formed in the second valve train element; an actuator piston slideably disposed in the actuator piston bore; a solenoid control valve; a first hydraulic fluid supply passage connected to the solenoid control valve; a hydraulic circuit extending between the actuator piston bore and the solenoid control valve; a solenoid actuated valve disposed in said hydraulic circuit between the solenoid valve and the actuator piston bore; a means for expanding the volume of the hydraulic circuit during times when the solenoid control valve opens to provide hydraulic fluid from the first hydraulic fluid supply passage to the solenoid actuated valve; a check valve disposed in the hydraulic circuit between the solenoid actuated valve and the actuator piston bore, wherein the solenoid actuated valve comprises a poker piston having a pin-shaped extension adapted to selectively open the check valve, wherein an area of the poker piston exposed to hydraulic pressure from the hydraulic circuit is less than an area of the actuator piston exposed to hydraulic pressure from the hydraulic circuit, and wherein the means for expanding the volume of the hydraulic circuit comprises; a means for biasing the actuator piston into the actuator piston bore, said means for biasing the actuator piston having a first spring load value; and a means for biasing the poker piston toward the check valve, said means for biasing the poker piston having a second spring load value, wherein the first spring load value is less than the second spring load value, and the second spring load value is less than a hydraulic pressure of the first hydraulic fluid supply passage. - View Dependent Claims (9, 10)
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11. A system for transferring engine valve actuation motion between first and second valve train elements, said system comprising:
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an actuator piston bore formed in the second valve train element; an actuator piston slideably disposed in the actuator piston bore; a solenoid control valve; a first hydraulic fluid supply passage connected to the solenoid control valve; a hydraulic circuit extending between the actuator piston bore and the solenoid control valve; a solenoid actuated valve disposed in said hydraulic circuit between the solenoid valve and the actuator piston bore; and a means for expanding the volume of the hydraulic circuit during times when the solenoid control valve opens to provide hydraulic fluid from the first hydraulic fluid supply passage to the solenoid actuated valve. a first hydraulic passage in said hydraulic circuit extending between the solenoid actuated valve and a mid-portion of the actuator piston bore; a second hydraulic passage in said hydraulic circuit extending between the solenoid actuated valve and an end wall portion of the actuator piston bore; a check valve disposed in the second hydraulic passage; and means for biasing the actuator piston into the actuator piston bore, wherein the solenoid actuated valve comprises a slug which selectively isolates the second hydraulic passage from hydraulic fluid communication with the solenoid control valve, and wherein the means for expanding the volume of the hydraulic circuit comprises; an annular recess provided in the actuator piston adapted to become unregistered with the first hydraulic passage when the actuator piston in an upward-most position; and a vent passage extending from the annular recess to a bottom surface of the actuator piston. - View Dependent Claims (12, 13)
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14. A system for transferring engine valve actuation motion between first and second valve train elements, said system comprising:
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an actuator piston bore formed in the second valve train element; an actuator piston slideably disposed in the actuator piston bore; a solenoid control valve; a first hydraulic fluid supply passage connected to the solenoid control valve; a solenoid actuated valve bore in hydraulic communication with the solenoid control valve; a solenoid actuated valve piston slideably disposed in the solenoid actuated valve bore, said solenoid actuated valve piston having first, second and third annular recesses; means for biasing the solenoid actuated valve piston towards the solenoid control valve; a second hydraulic fluid supply passage connected to the solenoid actuated valve bore; a first hydraulic fluid vent passage connected to the solenoid actuated valve bore; a second hydraulic fluid vent passage connected to the solenoid actuated valve bore; a first actuator hydraulic passage extending between an upper portion of the actuator bore and the solenoid actuated valve bore; and a second actuator hydraulic passage extending between a lower portion of the actuator bore and the solenoid actuated valve bore, wherein the position of the solenoid actuated valve piston is selectively controlled by the solenoid control valve to provide hydraulic communication (1) between the second hydraulic fluid supply passage and the first actuator hydraulic passage, and between the second hydraulic fluid vent passage and the second actuator hydraulic passage, and (2) between the second hydraulic fluid supply passage and the second actuator hydraulic passage, and between the first hydraulic fluid vent passage and the first actuator hydraulic passage. - View Dependent Claims (15, 16, 17, 18)
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Specification