Fully variable electro-hydraulic valve system

A fully variable electro-hydraulic valve system, comprising:

• a camshaft and a valve assembly;
• a sliding sleeve, a spiral shaft, a piston, and a reset spring, wherein the sliding sleeve is provided with a first end and a second end which are disposed oppositely, the sliding sleeve is provided with an oil inlet hole and a limiting oil hole, the spiral shaft is provided with a first end and a second end which are disposed oppositely, the spiral shaft is provided with a spiral structure, the spiral shaft and the piston are slidably connected with the sliding sleeve respectively in a sealing manner, an inner cavity between the spiral shaft and the piston is known as a sliding sleeve cavity, the reset spring is clamped and pressed between the spiral shaft and the piston, the piston abuts against the valve assembly, and the spiral shaft is axially controlled by a cam surface of the camshaft;
• and
• wherein a gear and rack mechanism, wherein the gear and rack mechanism comprises control gears and a rack, and the rack is driven by a linear execution mechanism controlled by an electronic control unit of an engine;
• wherein
• wherein a limiting sleeve is disposed outside the sliding sleeve, the limiting sleeve is fixed relative to the engine, the sliding sleeve and the limiting sleeve are rotatably mounted, and the sliding sleeve is restrained by an axial limiting structure;
• the limiting sleeve is provided with a first oil hole of the limiting sleeve and a second oil hole of the limiting sleeve, a first annular groove and a second annular groove are formed in the inner wall of the limiting sleeve, the first oil hole of the limiting sleeve communicates with the limiting oil hole via the first annular groove, the second oil hole of the limiting sleeve communicates with the oil inlet hole via the second annular groove, the first oil hole of the limiting sleeve and the second oil hole of the limiting sleeve respectively communicate with a low-pressure oil path of the engine, and a one-way valve is disposed on a connecting pipeline between the second oil hole of the limiting sleeve and the low-pressure oil path of the engine;
• wherein the spiral structure comprises a spiral groove formed in a circumferential surface of the spiral shaft, a groove surface, close to the first end of the spiral shaft, of the spiral groove, is a spiral surface, a part between the spiral surface and the first end of the spiral shaft is a blockage part capable of blocking the limiting oil hole, the spiral groove is provided with an oil through hole, the oil through hole communicates with the spiral groove and the sliding sleeve cavity, and when the spiral groove communicates with the limiting oil hole, the sliding sleeve cavity communicates with the low-pressure oil path of the engine for pressure relief;
• wherein spiral shaft axial projection portions are disposed at the first end of the spiral shaft, the spiral shaft axial projection portions are provided with spiral shaft abutting planes, piston axial projection portions are disposed at the end, opposite to the spiral shaft, of the piston, and head portions of the piston axial projection portions are provided with piston abutting planes;
• wherein the sliding sleeve is provided with a first positioning pin, the piston is provided with a first guide groove extending axially, and the first positioning pin extends into the first guide groove;
• the spiral shaft is provided with a second guide groove, the second guide groove extends in the axial direction of the spiral shaft, a second positioning pin extends into the second guide groove, and the second positioning pin is fixed relative to the engine;
• and
• wherein the control gears are disposed at the second end of the sliding sleeve, the gear and rack mechanism is further provided with a limiting device and a return spring, and when the return spring enables the rack to move to an extreme position limited by the limiting device, the piston abutting planes abut against the spiral shaft abutting planes, the limiting oil hole is blocked by the blockage part of the spiral shaft, and the valve stroke of the valve assembly is controlled by the camshaft.

A fully variable electro-hydraulic valve system, comprising:

• a camshaft and a valve assembly;
• a sliding sleeve, a sliding shaft, a piston, and a reset spring, wherein the sliding sleeve is fixed relative to an engine, the sliding shaft and the piston are slidably connected with the sliding sleeve respectively in a sealing manner, an inner cavity between the sliding shaft and the piston is known as a sliding sleeve cavity, the reset spring is clamped and pressed between the sliding shaft and the piston, the piston abuts against the valve assembly, and the sliding shaft is axially controlled by a cam surface of the camshaft;
• wherein the sliding shaft is provided with a first end and a second end which are disposed oppositely, the second end of the sliding shaft is in transmission connection with a gear and rack mechanism comprising control gears and a rack, the control gears are disposed at the second end of the sliding shaft, and the rack is driven by a linear execution mechanism controlled by an electronic control unit of the engine;
• wherein the sliding sleeve is provided with an oil inlet hole and an oil through hole, the oil inlet hole and the oil through hole respectively communicate with a low-pressure oil path of the engine, and a one-way valve is disposed on a connecting pipeline between the oil inlet hole and the low-pressure oil path of the engine;
• wherein
• wherein the sliding shaft is provided with a limiting oil hole communicating with the sliding sleeve cavity, a spiral groove is formed in the inner hole wall of the sliding sleeve, a groove surface, close to the second end of the sliding shaft, of the spiral groove, is a spiral surface, the spiral groove communicates with the oil through hole, and when the spiral groove communicates with the limiting oil hole, the sliding sleeve cavity communicates with the low-pressure oil path of the engine for pressure relief;
• wherein sliding shaft axial projection portions are disposed at the first end of the sliding shaft, the sliding shaft axial projection portions are provided with sliding shaft abutting planes, piston axial projection portions are disposed at the end, opposite to the sliding shaft, of the piston, and head portions of the piston axial projection portions are provided with piston abutting planes;
• wherein the sliding sleeve is provided with a positioning pin, the piston is provided with a guide groove extending axially, and the positioning pin extends into the guide groove;
• and
• the gear and rack mechanism is further provided with a limiting device and a return spring, and when the return spring enables the rack to move to an extreme position limited by the limiting device, the piston abutting planes abut against the sliding shaft abutting planes, the limiting oil hole is blocked by a non-groove part of the sliding sleeve, and the valve stroke of the valve assembly is controlled by the camshaft.