Patent Application
20170159514
The invention relates to a method and apparatus for intake and exhaust valve actuation in internal combustion engines.
An internal combustion engine generates power by burning fuel in a combustion chamber. Current intake and exhaust valves can be controlled and operated by camshafts and cams located in the engine. Intake valves can be opened in order to admit fuel and air into a cylinder for combustion, while exhaust valves can be opened to allow combustion gas to escape from the cylinder. The cams can be fixed profile cams which can provide difficulty in adjusting timings or amounts of engine valve lifts needed to optimize valve opening times and lift for varying engine operations. A lost motion device can be used between a valve and a cam on a camshaft for transmitting varying amounts of the cam motion to the valve. Current lost motion systems located between the cam on the camshaft and the valve use a master piston which displaces fluid from a hydraulic chamber into a hydraulic chamber of a slave piston. The slave piston can act on the engine valve for opening the valve. The hydraulic system generally includes added components such as cam sensors, oil control valves, phasers, guides, timing chains, tensioners, sprockets, bearing caps, and miscellaneous bolts and fasteners. The need for the added components in order to operate a lost motion system can increase valve train inertia, which can be problematic at high engine speeds. The added components can also increase complexity and cost. Valve actuation systems have been disclosed in U.S. Pat. No. 8,365,691; U.S. Pat. No. 6,997,148; U.S. Pat. No. 6,425,357; U.S. Pat. No. 5,645,031; U.S. Pat. No. 4,716,3; U.S. Pat. No. 2,072,437; U.S. Patent Application No. 2011/0197833; and W.O. Patent Application No. 2007/142724.
It can be desirable to minimize the additional components by entirely eliminating various components, by way of example and not limitation, such as camshafts, bearings, timing chains, guides, sprockets, tensioners, and phasers. It can also be desirable to eliminate the camshaft as an additional component due to the added size and weight that the camshaft adds to the valve train. To overcome the limitation of current technology, the disclosed crankshaft driven valve actuation system eliminates the camshaft and uses at least one connecting rod mounted for rotation with respect to a crankshaft by a crankpin located on the crankshaft. The at least one connecting rod can be operable for reciprocating a master piston for pressurizing fluid to drive reciprocal fluid flow within the crankshaft driven valve actuation system. The use of a connecting rod can eliminate added components currently used in valve actuation systems such as the cam sensors, oil control valves, phasers, guides, timing chains, tensioners, sprockets, bearing caps, and miscellaneous bolts and fasteners. The crankshaft driven valve actuation system can control the opening and closing of a plurality of hydraulically actuatable valves, either intake valves or exhaust valves, or both intake and exhaust valves. The valves can be associated with a plurality of cylinders of an internal combustion engine. The crankshaft driven valve actuation system can include at least one accumulator for reciprocally receiving and releasing fluid in a lost motion manner when modification of valve actuation is desired, and for maintaining fluid pressure and volume in the crankshaft driven valve actuation system.
A crankshaft driven valve actuation system can include a crankshaft driven by the engine and rotatable about a primary longitudinal rotational axis and at least one fluid piston pump connected to the crankshaft for generating a reciprocating fluid flow in response to rotation of the crankshaft. The system can include at least one control valve operable for isolating and providing fluid flow between the at least one accumulator and the at least one fluid piston pump. The fluid piston pump can include a master piston, a fluid pumping chamber, and at least one fluid passage corresponding to at least one of a plurality of hydraulically actuatable valves. The master piston can be operable for reciprocally driving fluid in and out of the at least one fluid passage with respect to the fluid pumping chamber. The system can include a connecting rod connected between the crankshaft and the master piston operable for reciprocating the master piston for reciprocally driving fluid toward the at least one fluid passage and for reciprocally drawing fluid out of the at least one fluid passage. The connecting rod can push or pull the master piston within the fluid pumping chamber creating sufficient working fluid pressure and volume to operably actuate one or more of a plurality of valves in fluid communication with the crankshaft driven valve actuation system as fluid flow reciprocates within the crankshaft driven valve actuation system fluid passages in response to reciprocation of the master piston driven by the connecting rod corresponding to rotation of the crankshaft. The at least one accumulator can provide a lost motion function for modifying a valve timing actuation curve of the hydraulically actuated valves during reciprocal fluid flow, while maintaining working fluid volume and pressure during the operating cycle and to make up for working fluid volume losses and pressure losses due to normal leakage during operation cycles. The working fluid, being an essentially incompressible working fluid, can allow reciprocal flowing movement of the working fluid through the crankshaft driven valve actuation system in response to reciprocal movement of the master piston as the master piston is driven by rotation of the connecting rod by the crankshaft. The master piston is in continuous fluid communication with the crankshaft driven valve actuation system fluid passages during operation of the internal combustion engine.
A method of operating a normally closed valve associated with one of a plurality of cylinders in a crankshaft driven valve actuation system of an internal combustion engine is disclosed. The crankshaft driven valve actuation can include at least one accumulator for maintaining fluid pressure and volume in the system. The method can include rotating a crankshaft of the internal combustion engine about a primary longitudinal rotational axis. The crankshaft can be connected to at least one fluid piston pump by a connecting rod. The method can further include generating a reciprocating fluid flow by the at least one fluid piston pump in response to rotation of the crankshaft, selectively providing fluid communication between a fluid pumping chamber of the at least one fluid piston pump and the valve to be controlled with the reciprocating fluid flow within fluid passages for driving the valve between a normally closed position and an open position in response to the reciprocating fluid flow, and selectively communicating at least one control valve for selectively providing fluid flow between the at least one accumulator and the at least one fluid piston pump for operating as a lost motion mechanism when modification or elimination of a valve timing actuation curve is desired during reciprocal fluid flow.
A method of assembling a crankshaft driven valve actuation system for controlling opening and closing a plurality of hydraulically actuated valves, either intake valves or exhaust valves or both intake and exhaust valves, can be used for valves associated with a corresponding plurality of cylinders in an internal combustion engine. The crankshaft driven valve actuation system can include a crankshaft driven by the engine and rotatable about a primary longitudinal rotational axis, and at least one accumulator for redirecting pressurized fluid reciprocating fluid flow to operate as a lost motion mechanism to modify valve actuation when desired. The method can include connecting a connecting rod to the crankshaft for rotation with respect to the crankshaft, assembling at least one fluid piston pump for reciprocation in response to rotation of the connecting rod by the crankshaft, connecting the at least one fluid pressure pump to at least one fluid passage for directing reciprocal fluid flow from the at least on fluid pressure pump in fluid communication with at least one valve to be controlled, and inserting at least one control valve operable for providing lost motion fluid flow between the at least one accumulator and the at least one fluid piston pump to modify valve timing actuation curve during reciprocal fluid flow. The method can include assembling a master piston reciprocally within a fluid pumping chamber of the at least one fluid pressure piston pump for generating reciprocal fluid flow in response to rotation of the connecting rod. The method can include connecting a linkage mechanism between the at least one fluid piston pump and the connecting rod for transferring reciprocal motion of the connecting rod to drive fluid toward the at least one fluid passage and to draw fluid from the at least one fluid passage.
Other applications of the present invention will become apparent to those skilled in the art when the following description of the best mode contemplated for practicing the invention is read in conjunction with the accompanying drawings.
The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein:
Referring now to
Referring now to
The crankshaft driven valve actuation system 30 can include at least one fluid piston pump 36, 36a, 36b having a master piston 38, 38a, 38b for movement within a housing defining at least one fluid pumping chamber 40, 40a, 40b, 40c, 40d. The fluid pumping chamber can provide a source of pressurized fluid in fluid communication with the plurality of valves 34a, 34b, 34c, 34d, 134a, 134b, 134c, 134d and the accumulator 46, 46a, 46b, 46c, 46d through fluid passages defining a reciprocal fluid flow path. The valve actuation system 30 can include a crankshaft 50 rotatable by the engine about a primary longitudinal rotational axis and crankpins 65a, 65b located on the crankshaft 50 and angularly offset with respect to one another. By way of example and not limitation, the crankpins 65a, 65b can be offset approximately 220° with respect to one another for controlling intake valves off from rotation of crankpin 65a and for controlling exhaust valves off from rotation of crankpin 65b. The valve actuation system 30 can include at least one connecting rod 62, 162 associated between the crankshaft 50 and the master piston 38, 38a, 38b. The at least one connecting rod 62, 162 can be mounted for rotation with respect to the crankshaft 50 on the crankpin 165a, 165b by at least one rod bearing 166a, 166b and operable for reciprocating the master piston 38, 38a, 38b between a first position in the at least one fluid pumping chamber 40, 40a, 40b, 40c, 40d and a second position in the at least one fluid pumping chamber 40, 40a, 40b, 40c, 40d. The master piston 38, 38a, 38b can pressurize a working fluid located in the at least one fluid pumping chamber 40, 40a, 40b, 40c, 40d for reciprocal flow through a plurality of fluid passages 72, 72a, 72b, 172a, 172b located in the crankshaft driven valve actuation system 30. The master piston 38, 38a, 38b can pressurize fluid toward a first fluid passage 72, 72a, 72b, when in the first position and can pressurize fluid toward a second fluid passage 172a, 172b when in the second position. The first and second position can be used for opening different sets of valves 34a, 34b; 34c, 34d; 134a, 134b; 134c, 134d. By way of example and not limitation, when master piston 38a, 38b are in the first position, pressurized fluid is in fluid communication with first fluid passages 72a, 72b enabling pressurized fluid to be directed to slave pistons 48a, 48b 148c, 148d depending on the position of control valves 64a, 64c, and when master piston 38a, 38b is in the second position, pressurized fluid is in fluid communication with second fluid passages 172, 172b enabling pressurized fluid to be directed to slave pistons 48c, 48d, 148a, 148b depending on the position of control valves 64b, 64d.
The actuation system 30 can include at least one control valve 56, 56a, 56b, 56c, 56d operable by a actuator 58, 58a, 58b, 58c, 58d between a first position 60a, 60b, 60c, 60d and a second position 62a, 62b, 62c, 62d. By way of example and not limitation, a control valve 56, 56a, 56b, 56c, 56d can have an actuator 58, 58a, 58b, 58c, 58d, such as a solenoid operated actuator, a piezoelectric operated actuator, or any other mechanically or electrically operated actuator for a control valve. The at least one control valve 56, 56a, 56b, 56c, 56d can provide fluid communication between the at least one fluid piston pump 36, 36a, 36b and the at least one accumulator 46, 46a, 46b, 46c, 46d. The first position 60a, 60b, 60c, 60d can be defined by preventing fluid communication between the at least one accumulator 46, 46a, 46b, 46c, 46d and the fluid passages 72, 72a, 72b, 172a, 172b. The second position 56c, 156c can be defined by providing fluid communication between the fluid passages 72, 72a, 72b, 172a, 172b and the at least one accumulator 46, 46a, 46b, 46c, 46d providing for fluid communication between the at least one fluid piston pump 36, 36a, 36b and the at least one accumulator 46, 46a, 46b, 46c, 46d.
By way of example and not limitation, a four stroke-four cylinder cycle can refer to travel of an engine piston between an intake stroke, a compression stroke, an ignition/combustion/power stroke, and an exhaust stroke, such that the at least one connecting rod 62, 162 can reciprocate the master piston 38 between a first and second position within the fluid pumping chamber 40, 40a, 40b, 40c, 40d to force fluid into the first or second fluid passages 72, 72a, 72b, 172a, 172b in order to open one of the two of the plurality of valves 34a, 34b; 34c, 34d; 134a, 134b; 134c, 134d based on the position of the corresponding at least one switching valve 64a, 64b, 64c, 64d. By way of example and not limitation, the valves 34a, 34b, 134c, 134d can correspond to two intake valves 34a, 34b associated with a first and fourth cylinder and two exhaust valves 134c, 134d associated with the second and third cylinder of a four cylinder internal combustion engine, while the valves 34c, 34d, 134a, 134b can correspond to two intake valves 34c, 34d associated with second and third cylinders and two exhaust valves 134a, 134b associated with a first and fourth cylinders of a four cylinder internal combustion engine. In other words, the first cylinder can be associated with intake valve 34a and exhaust valve 134a, the fourth cylinder can be associated with intake valve 34b and exhaust valve 134b, the second cylinder can be associated with intake valve 34c and exhaust valve 134c, and the third cylinder can be associated with intake valve 34d and exhaust valve 134d.
As illustrated in
As illustrated in
By way of example and not limitation, as illustrated in
The simplified schematic of
The first position of the first and second master pistons 38a, 38b can be defined by pressurized fluid being driven out of the fluid chambers 40a, 40c into corresponding first fluid passages 72a, 72b for selectively opening intake valve 34a or 34b and exhaust valve 134c or 134d depending on the position of control valves 64a and 64c, or for selectively being diverted for lost motion to accumulator 46a or 46c depending on the position of control valves 56a, 56c. When the first and second master pistons 38a, 38b are driven to the first position, fluid is drawn into pump chambers 40b, 40d from fluid passages 172a, 172b for selectively closing intake valve 34c or 34d and exhaust valve 134a or 134b depending on the position of control valves 64b, 64d, or for selectively being diverted for lost motion to accumulator 46b, 46d depending on the position of the control valves 56b, 56d.
The second position of the master piston 38a, 38b can be defined by pressurized fluid being driven out of fluid chambers 40b, 40d into corresponding second fluid passages 172a, 172b for selectively opening intake valve 34c or 34d and exhaust valve 134a or 134b depending on the position of control valves 64b and 64d, or for selectively being diverted for lost motion to accumulator 46b or 46d depending on the position of control valves 56b, 56d. When the first and second master pistons 38a, 38b are driven to the second position, fluid is drawn into pump chambers 40a, 40c from fluid passages 72a, 72b for selectively closing intake valve 34a or 34b and exhaust valve 134c or 134d depending on the position of control valves 64a, 64c, or for selectively being diverted for lost motion to accumulator 46a, 46c depending on the position of the control valves 56a, 56c.
As illustrated in
By way of example and not limitation, the crankshaft driven valve actuation system 30 can operate as indicated in the following table.
When the crankshaft is in the 0° position and the switching valves 64a, 64b, 64c are in a first position 68a, 68b, 68c and switching valve 64d is in a second position 70d, the first intake valve 34a can be in an open position and exhaust valve 134b can be closing, while the remaining valves 34b, 34c, 34d, 134a, 134c, 134d remain closed. When the crankshaft is in the 40° position and the switching valves 64a, 64b, 64d are in a first position and switching valve 64c is in the second position 70c, the fourth exhaust valve 134d can be in an open position and intake valve 34a can be closing, while the remaining valves 34b, 34c, 34d, 134a, 134b, 134c remain closed. When the crankshaft is in the 180° position and the switching valves 64a, 64b, 64d are in a first position 68a, 68b, 68d and switching valve 64c is in a second position 70c, the third intake valve 34c can be in an open position and exhaust valve 134d can be closing, while the remaining valves 34a, 34b, 34d, 134a, 134b, 134c remain closed. When the crankshaft is in the 220° position and the switching valves 64a, 64b, 64c, 64d are in a first position 68a, 68b, 68c, 68d, the first exhaust valve 134a can be in an open position and intake valve 34c can be closing, while the remaining valves 34a, 34b, 34d, 134b, 134c, 134d remain closed. When the crankshaft is in the 360° position and the switching valves 64b, 64c, 64d are in a first position 68b, 68c, 68d and the switching valve 64a is in a second position 70a, the first intake valve 34b can be in an open position and exhaust valve 134a can be closing, while the remaining valves 34a, 34c, 34d, 134b, 134c, 134d remain closed. When the crankshaft is in the 400° position and the switching valves 64b, 64c, 64d are in a first position 68b, 68c, 68d and the switching valve 64a is in a second position 70a, the third exhaust valve 134c can be in an open position and the second intake valve 34b can be closing, while the remaining valves 34a, 34c, 34d, 134a, 134b, 134d remain closed. When the crankshaft is in the 540° position and the switching valves 64a, 64c, 64d are in a first position 68a, 68c, 68d and switching valve 64b is in a second position 70b, the fourth intake valve 34d can be in an open position and the third exhaust valve 134c can be closing, while the remaining valves 34a, 34b, 34c, 134a, 134b, 134d remain closed. When the crankshaft is in the 580° position and the switching valves 64a, 64c, are in a first position 68a, 68c and switching valves 64b, 64c are in a second position 70b, 70c, the second exhaust valve 134b can be in an open position and the fourth intake valve 34d can be closing, while the remaining valves 34a, 34b, 34c, 134a, 134c, 134d remain closed.
The plurality of intake valves 34a, 34b, 34c, 34d are operable in response to rotation of the first connecting rod 62 and can correspond to intake valves associated with each cylinder of a four cylinder internal combustion engine. The plurality of exhaust valves 134a, 134b, 134c, 134d are operable in response to rotation of the second connecting rod 162 and can correspond to exhaust valves 134a, 134b, 134c, 134d associated with each cylinder of the four cylinder internal combustion engine. The master pistons 38a, 38b can rotate between first and second positions in response to rotation of the crankshaft rotating the connecting rod 62, 162 around the crankpins 165a, 165b via the corresponding rod bearings 166a, 166b.
It should be recognized by those skilled in the art that the single switching valve 64a, 64b, 64c, 64d can be replaced with two separate open/closed valves, where a separate switching valve is provided for each intake valve, without departing from the disclosure of the present invention. It should also be recognized by those skilled in the art that additional connecting rods and rod bearings coupled to corresponding crankpins on the crankshaft can be provided to control operation of the valves of additional cylinders in a similar manner to that described above without departing from the disclosure of the present invention. It should further be recognized by those skilled in the art, that additional master piston/chambers and closed fluid flow paths can be provided similar to the disclosure above to provide hydraulic valve actuation of the valves individually or in pairs without departing from the disclosure of the present invention. Finally, it should be recognized by those skilled in the art that the four stroke-four cylinder engine cycle is by way of example and not limitation, since the crankshaft driven valve actuation system can be modified to accommodate different engine configurations, such as by way of example and not limitation, two or more cylinder engine configurations, such as three cylinder, six cylinder, eight cylinder, or more than eight cylinder engine configurations without departing from the disclosure of the present invention.
As illustrated in
Advantages of implementing the disclosed crankshaft driven valve actuation system 30 in an engine can include weight savings by eliminating additional components such as camshafts, cam sensors, oil control valves, phasers, guides, timing chains, tensioners, sprockets, bearing caps, and miscellaneous bolts and fasteners. The disclosed crankshaft driven valve actuation system 30 can also reduce parasitic losses in the engine resulting from the use and wear of the additional components. The package size of the engine can also be reduced significantly by particularly removing camshafts. The disclosed crankshaft driven valve actuation system 30 can provide significant economic advantages by reducing production costs associated with the engine due to removing the cost of the additional components. The use of multiple control valves and connecting rods can also provide flexibility of intake and exhaust valve motion control through selection of the desired number of independent reciprocal pressurized fluid flow reciprocal paths.
Referring now to
In operation, rotating the crankshaft 50 of the internal combustion engine about a primary longitudinal rotational axis rotates the crankpins 165a, 165b about a secondary longitudinal rotational axis offset from the primary longitudinal axis. The rotation of the crankpins 165a, 165b can transfer movement to the connecting rods 62, 162 for reciprocating the master pistons 38a, 38b within the corresponding fluid pumping chambers 40a, 40b, 40c, 40d. The fluid pumping chambers 40a, 40b, 40c, 40d provide reciprocal fluid flow within fluid passages 72a, 72b, 172a, 172b to be selectively directed by control valves 56a, 56b, 56c, 56d, 64a, 64b, 64c, 64d associated with corresponding accumulators 46a, 46b, 46c, 46d and valves 34a, 34b, 34c, 34d, 134a, 134b, 134c, 134d located in the crankshaft driven valve actuation system 30 for driving each of the valves 34a, 34b, 34c, 34d, 134a, 134b, 134c, 134d between a normally open position and a closed position. Reciprocation of the master piston 38a, 38b can reciprocally drive fluid out of and draw working fluid back into the fluid pumping chambers 40a, 40b, 40c, 40d for providing reciprocal fluid flow within a closed fluid flow path in fluid communication with control valves 56a, 56b, 56c, 56d, 64a, 64b, 64c, 64d.
A fluid reservoir or sump 90a, 90b, 90c, 90d can provide fluid to a fluid pump 92a, 92b, 92c, 92d for delivery through a check valve 96a, 96b, 96c, 96d to the accumulator 46a, 46b, 46c, 46d. When the control valves 56a, 56b, 56c, 56d are in a first position, the corresponding accumulator 46a, 46b, 46c, 46d is isolated from the corresponding reciprocal fluid flow passages 72a, 72b, 172a, 172b. When the control valves 56a, 56b, 56c, 56d are in a second position 62a, 62b, 62c, 62d, the corresponding accumulator 46a, 46b, 46c, 46d is placed in fluid communication with the corresponding reciprocal fluid flow passages 72a, 72b, 172a, 172b. The accumulators 46a, 46b, 46c, 46d can operate as a lost fluid motion reservoir when modification or elimination of a valve actuation curve is desired during reciprocal fluid flow from the particular fluid pumping chambers 40a, 40b, 40c, 40d of a corresponding fluid pump 36a, 36b, while also acting as a pressurized fluid reservoir for holding a volume of fluid under pressure and for maintaining the fluid pressure and volume in the crankshaft driven valve actuation assembly 30. In other words, the accumulator 46a, 46b, 46c, 46d can be used to modify the shape of a valve timing curve and allow for lost motion in the hydraulic system by reducing motion of a valve while directing fluid flow to the corresponding accumulator 46a, 46b, 46c, 46d. The inclusion of the accumulator 46a, 46b, 46c, 46d in the system can allow a valve in fluid communication with the accumulator to open late, close early, open partially, or prevent opening of the valve all together. The accumulator 46a, 46b, 46c, 46d can include an accumulator spring 47a, 47b, 47c, 47d for maintaining pressure of a predetermined volume of fluid in the absence of pump 92a, 92b, 92c, 92d running. The accumulator 46a, 46b, 46c, 46d can provide fluid flow to the hydraulic valve actuation assembly 30 when the corresponding control valve 56a, 56b, 56c, 56d is in a second valve position 62a, 62b, 62c, 62d.
The fluid can flow through the high-speed switching valves 64a, 64b, 64c, 64d provides for selective fluid communication between the master piston 38a, 36b and a corresponding one of the plurality of slave piston 44a, 44b, 44c, 44d, 144a, 144b, 144c, 144d corresponding to a valve 34a, 34b, 34c, 34d, 134a, 134b, 134c, 134d, respectively. The switching or skipping function can be used to make use of the lost fluid motion that would otherwise occur when controlling a single engine valve function with the crankshaft driven valve actuation system 30. It is contemplated that more than one switching valve 64a, 64b, 64c, 64d could be used with an internal combustion engine having additional cylinders and valves. The control valve 56a, 56b, 56c, 56d can be in the second valve position 62a, 62b, 62c, 62d providing for fluid flow between the fluid piston pump 36a, 36b and a corresponding accumulator 46a, 46b, 46c, 46d. The control valve 56a, 56b, 56c, 56d can be in the first valve position 60a, 60b, 60c, 60d isolating the corresponding accumulators 46a, 46b, 46c, 46d from the reciprocal fluid flow passages 72a, 72b, 172a, 172b, while providing fluid communication between the fluid piston pump 36a, 36b and a corresponding control valve 64a, 64b, 64c, 64d for selected fluid communication with one of a pair of valves 34a or 34b; 34c or 34d; 134a or 134b; 134c or 134d depending on the position of the control valve 64a, 64b, 64c, 64d. Each valve 34a, 34b, 34c, 34d, 134a, 134b, 134c, 134d can include a corresponding slave piston 44a, 44b, 44c, 44d, 144a, 144b, 144c, 144d. The slave piston 44a, 44b, 44c, 44d, 144a, 144b, 144c, 144d can be normally biased toward a valve closed position by a corresponding biasing spring 48a, 48b, 48c, 48d, 148a, 148b, 148c, 148d. When the slave piston 44a, 44b, 44c, 44d, 144a, 144b, 144c, 144d is moved in response to fluid communication with pressurized fluid, the pressurized fluid can overcome the spring force to move the corresponding slave piston 44a, 44b, 44c, 44d, 144a, 144b, 144c, 144d and open the corresponding valve 34a, 34b, 34c, 34d, 134a, 134b, 134c, 134d. Fluid can be returned from the cylinder of a slave piston 44a, 44b, 44c, 44d, 144a, 144b, 144c, 144d back to the corresponding fluid pumping chamber 40a, 40b, 40c, 40d by passing back through the corresponding control valve 64a, 64b, 64c, 64d or through optional corresponding check valves 80b, 80c, 80d, 80e, 180b, 180c, 180d, 180e. Fluid flowing toward the switching valves 64a, 64b, 64c, 64d can be prevented from flowing to cylinders of the slave valves by corresponding check valves 80b, 80c, 80d, 80e, 180b, 180c, 180d, 180e.
A method of assembling a crankshaft driven valve actuation system 30 for controlling opening and closing a plurality of hydraulically actuated valves, either intake valves 34a, 34b, 34c, 34d or exhaust valves 134a, 134b, 134c, 134d, can be corresponding to a plurality of cylinders in an internal combustion engine. The crankshaft driven valve actuation system 30 can include a crankshaft 50 driven by the engine and rotatable about a primary longitudinal rotational axis, a fluid piston pump 36a, 36b driven by the crankshaft rotation for providing a source or pressurized fluid with reciprocal flow, an engine valve responsive to the reciprocal flow of the pressurized fluid to move from a normally closed position to an open position, and at least one accumulator 46, 46a, 46b, 46c, 46d for maintaining a predetermined volume of pressurized fluid. The method can include connecting a connecting rod 62, 62a, 62b to the crankshaft 50 for converting rotary movement into reciprocating movement driven by rotation of the crankshaft 50, assembling at least one fluid piston pump 36, 36a, 36b for reciprocation in response to reciprocating movement of the connecting rod 62, 62a, 62b by the crankshaft 50, fluidly connecting the at least one fluid pressure pump 36, 36a, 36b to at least one fluid passage 72a, 72b, 172a, 172b for directing reciprocal fluid flow of pressurized fluid from the at least on fluid pressure pump 36, 36a, 36b, 36c, 36d in fluid communication with at least one slave piston actuator 44a, 44b, 44c, 44d, 144a, 144b, 144c, 144d of a corresponding engine valve 34a, 34b, 34c, 34d, 134a, 134b, 134c, 134d to be controlled; and inserting at least one control valve 56a, 56b, 56c, 56d for selectively providing fluid communication between the at least one piston pump 36, 36a, 36b and at least one accumulator 46a, 46b, 46c, 46d for lost motion reciprocal fluid flow of pressurized fluid.
The method can further include connecting a linkage mechanism 168 between a fluid piston pump 36 and a connecting rod 62 for transferring reciprocal motion of the connecting rod 62 to drive fluid toward the at least one fluid passage 72a, 72b, 172a, 172b and to draw fluid from the at least one fluid passage 72a, 72b, 172a, 172b creating a reciprocal flow of pressurized fluid. The method can further include selectively providing fluid communication during reciprocal fluid flow within the at least one fluid passage 72a, 72b, 172a, 172b with at least one slave piston actuator 44a, 44b, 44c, 44d, 144a, 144b, 144c, 144d to actuate a corresponding engine valve 34a, 34b, 34c, 34d, 134a, 134b, 134c, 134d. The method can further include assembling a master piston 38, 38a, 38b for reciprocation within a fluid pumping chamber 40, 40a, 40b of the a fluid pressure piston pump 36, 36a, 36b for generating reciprocal fluid flow in response to rotation of the connecting rod 62, 162.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is permitted under the law.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2015/038782 | 7/1/2015 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62025255 | Jul 2014 | US |
