Abstract
A variable valve timing device for an engine utilizing hydraulically actuated valves. A cam follower block, complete with radial bores, and cam followers within these bores, is pivotally mounted about a rotating camshaft. The rotating camshaft displaces the cam followers within the bores, causing the followers to displace hydraulic fluid, forcing movement of either, an intake or exhaust valve, by hydraulic force on a secondary hydraulic cylinder. The cam follower block angular position about the camshaft is mechanically adjustable during operation. Separate cam follower blocks are used for intake and exhaust valve operation such that the valve timing of the intake and exhaust valves can be changed independently.
Claims
1. A variable valve timing device for an engine having a crankshaft and a plurality of valves movable between open and closed positions, said variable valve timing device comprising: a camshaft rotatably coupled to the crankshaft, said camshaft rotates in a fixed orientation relative to the crankshaft; a plurality of cam lobes defining an eccentric profile and fixedly disposed on said camshaft; a plurality of blocks each defining at least one bore and configured to independently rotate relative to one another; means for actuating at least one said block for controlling independent rotation of at least one of said block relative to another one of said blocks; at least one cam follower operably disposed within at least one said bores and configured to follow said eccentric profile of one of said cam lobes for selectively actuating the valves; wherein each of said cam followers is adjusted relative to said camshaft independent of other cam followers.
2. The variable valve timing device of claim 1, wherein independent adjustment of at least one said cam followers selectively manipulates timing of opening and closing of at least one said valves.
3. The variable valve timing device of claim 2, wherein said timing of opening and closing of each of said valves is independent of at least one of valve lift and/or duration.
4. The variable valve timing device of claim 1, further including hydraulic fluid or some other alternate liquid and a controller or other means of regulating pressure and flow of said hydraulic fluid for independently adjusting at least one said cam followers.
5. The variable valve timing device of claim 1, wherein said valves are further defined as intake valves and exhaust valves.
6. The variable valve timing device of claim 1, wherein said at least one cam followers further include lifters.
7. The variable valve timing device of claim 1, wherein said at least one cam followers further include pistons.
8. The variable valve timing device of claim 1, wherein said camshaft is further defined as a single-lobe camshaft.
9. The variable valve timing device of claim 1, wherein said camshaft is further defined as a two-lobe camshaft.
10. The variable valve timing device of claim 1, wherein said camshaft is further defined as a multi-intake, multi-exhaust lobe camshaft.
Description
BRIEF DESCRIPTION OF DRAWINGS
(1) FIG. 1 shows a general schematic (with the valve block sectioned) of the present invention as it may look in one of the possible arrangements (radial type). This figure shows the rotation of a camshaft internal to the radial block of the present invention. The figure shows the rotation of the camshaft displacing the camshaft followers, [[lifters]] and in turn, displacing the hydraulic fluid. The figure also shows a possible arrangement of how the actuator may be oriented to rotate the block.
(2) FIG. 2 shows a side view of the radial arrangement. This figure also shows the separate blocks for the intake and exhaust valves to illustrate how they may be adjusted individually and independently.
(3) FIG. 3 shows is a general schematic (with the valve block sectioned) of the present invention as it may look in one of the possible arrangements (inline or single type). This figure shows the rotation of a camshaft internal to the radial block of the present invention. The figure shows the rotation of the camshaft displacing the camshaft followers, and in turn, displacing the hydraulic fluid. The figure also shows a possible arrangement of how the actuator may be oriented to rotate the block.
(4) FIG. 4 shows is a side view of the inline or single arrangement, with the valve blocks being sectioned. This figure illustrates the present invention as it may look in one of the possible arrangements (inline or single type). This figure shows the rotation of a camshaft internal to the inline block of the present invention. The figure shows the rotation of the camshaft displacing the camshaft followers, and in turn, displacing the hydraulic fluid. This figure also shows the separate valve blocks for the intake and exhaust valves to illustrate how they may be adjusted individually and independently.
(5) FIG. 5 shows a cylinder head arrangement that may be utilized with the present invention. The figure shows the hydraulic line supplying pressure to a linear hydraulic valve actuator. This pressure is the driving force that will open the valve. Additionally, the present invention can be used in typical rocker arm configurations by utilizing a piston to apply force to the pushrod.
DETAILED DESCRIPTION OF THE INVENTION
(6) While the following description details the preferred embodiments of the present invention, it is understood that the invention is not limited in its application to the details of construction and arrangement of the parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced in a variety of ways and methods. FIG. 1, FIG. 2, FIG. 3, FIG. 4 and FIG. 5, illustrate the variable valve timing device of the present invention. The block assembly is comprised of the two blocks, intake cam follower block, 1, and exhaust cam follower block, 2. These two cam follower blocks are individual casings attached to one another by some means that would allow independent rotation of one in relation to the other, such as a bearing, sleeve or other free moving connection. The two cam follower blocks are housings which encase cylinder bores, fitted with cam followers, 3, which may or may not have rollers at the interface where the cam follower contacts the camshaft. These cam followers displace hydraulic fluid, 4, when moved by means of contact with the camshaft or camshafts, 5. The camshaft is turned at one-half the crankshaft speed via some means of mechanical connection between the camshaft and the engine's crankshaft. The hydraulic fluid displaced through the hydraulic lines, 7, activates the rocker/valve mechanisms or hydraulic valve actuators, 8, to move the engine's valves, 9. With the engine running, the cam follower blocks are rotated angularly by means of some type of actuator 6, that rotates the blocks by means either electrically, hydraulically or some other method and is controlled by an Electronic Control Module (ECM), manually or by other ways. These actuators, can control both the intake block and exhaust block independently, thereby accomplishing the objective of effectively varying the effective lobe separation angle of the camshaft, effectuating operational variances in engine performance, efficiency and emissions output. The intake and exhaust blocks may be designed and manufactured in one piece for collective movement of ALL intake valves and collective movement of ALL exhaust valves, or the blocks may be designed and manufactured as individual, discrete components to allow advancing or retarding of individual valves. These characteristics can be varied with computers or other methods to achieve the desired end effect. A preferred embodiment of the implementation of the present invention may include the hydraulic fluid displaced by the cam followers to be supplied, through a hydraulic line, 7, to some hydraulic valve actuator in order to actuate a valve of an engine, 10.
