CA2227025A1

CA2227025A1 - Attain's new camshaft locations, or "ancam-l"

Info

Publication number: CA2227025A1
Application number: CA002227025A
Authority: CA
Inventors: Nicholas M. Ottlyk
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-03-20
Filing date: 1998-03-20
Publication date: 1999-09-20

Abstract

A separate component, fabricated out of light alloys, or composite materials, called a "cradle", is secured in the center of an SOHC/DOHC engine short-block, with the cylinder banks of the said engine angled between 45° to 90°, and houses a camshaft with its bearings and pushrod guides for Attain type intake and exhaust valves of the said engine, which uses either a wedge-type, or a hemi-spherical combustion chamber with the manufacturer's original, or Attain-type engine ports.

Description

intro-i naz~r~rar a The majority of designs submitted under the name of ANCAM-L, is centered around New Camshaft Locations; the fact that they are "new"or a novelty, stems from two factors: it is either a deliberate new placement (in the engine block), or it is a consequence of other elements, such as Attains New Engine Ports, or New Valve Trains, categorized mostly as "Prior Art."
While in Europe - and possibly in Japan _ the pushrod engine is a vanishing species. But the Detroit's Big Three still recognize this motor as an engine of high-performance potential that comes in at a low cost and that is relatively easy to produce and to maintain. Witness the presence of Corvette and the Viper.
Besides the regular, on-going production, almost the entire huge automotive after-market is based on pushrod engines, namely the ubiquitous Chevy 350 CID motor, of which several milllion are running strong, after almost 50 years of production. Therefore, the longevity of the pushrod engine is probably good for another 25 to 30 years - well beyond the year 2000 - i:F one dares to look that far ahead. Attains proposals revitalize this trend and bring in a new dimension in the Variable Valve Train technology, that can now be adapted to a pushrod-type motor.
Also, as it stands now, every Detroit auto-manufacturer producing pushrod and SOHC/DOHC motors, must use two completely different short-blocks, which is very costly from a production point-of-view. Attains proposal to use only one could: save them several hundred million dollars.

intro-ii PRESENTATION FORMAT
Tne main thrust of the ANCAM-L submission lies in the new camshaft locations; as these engines use many Prior Art components, these are always mentioned in the text and their Figures are assembled in an Appendix for quick reference.
In addition to the claims for new camshaft locations, there is a valve train feature, called ORS/RRA, which is used in many of the said engines.
The last claim is called XANTA II, and it is a variation to a previously submitted design called: XANTA.
Most of the Figures of complete engines are 64~
reductions of designs drawn in actual-size. However, due to the prevailing rules, they cannot be presented here in their original format.

intro-iii OHV ENGINES BY ATTAIN
Introduction Attains proposals are intended only for "V" -type engines with OHV (pushrod-type) valve trains. The V-type motor is an engine with 45~to 90~(degrees) between its cylinder banks.
The proposals are not suitable for IL (in-line) engines, nor for "boxer" motors, with opposed cylinder banks.
Each model year, more than 10 million engines leave the North American assembly lines; the exact percentage that the V-type, OHV engines, occupy in the overall 10 million total, is not exactly known to the writer but a close estimate would be between 3 to 4 million units. These motors go into trucks, cars, sports utility vehicles, and others - and reach even to the top performance echelons: they are found in the GM's Corvettes and it the Vipers, built by the Chrysler Corporation.
As alluded to earlier, each North American manufacturer uses two different engine blocks and assembly lines to produce V-type motors: one for the OHV (pushrod-type) and the other f=or the SOHC/DOHC engines - which is very costly. Attain proposes to use only one short-block for both types, which would save the producers several hundred million dollars, when the production facilities are streamlined.

MAIN DIFFERENCES
BETWEEN THE
V-TYPE ENGINES: OHV vs. SOHC/DOHC
An OHV Short-Block & Cylinder Heads A single camshaft is deeply wedged in the center of a block, surrounded by an intricate array of galleries and passages, forcing oil under pressure to first enter the hydraulic adjusters and then climb up via the pushrods into the engines cylinder head to lubricate all valve-train components.
This ca~;ting is relatively heavy and complex, on account of all passages around the camshaft.
The OHV cylinder heads are fairly simple but are normally limited to 2 valves/head and can only use the wedge-type combustion chamber, which allows in-line valves with some small angles between them.
An SOHC/DOHC Short-Block & Cylinder Heads Its block is simple and straight-forward: the cylinders with its jackets aim down into the barrel-shape crank-case; it:s cylinder heads are lubricated via drilled passages in the cylinder block.
The cylinder heads are tall, heavy and can be very complex, raising both their costs and heights.
Conclusions The OHV engine has a heavier short block but lighter cylinder' heads - while the SOHC/DOHC motor has a light short-block and heavy cylinder heads.

- 2 -Figures For V-Type Engines Figure 1, shows a 'generic' type of a V-8 engine, illustrating the relative simplicity of the cylinder heads.
Figure 2, is an image of a large-bore General Motors' V-8 engine; it shows clearly the complexity of oil passages and galleries in the center of the V, of its short-block - and the relative simplicity - and substantial height -of its c~~linder heads.
Figure 3, is a cross-section of an SOHC motor made by BMW. It employs 2 V/H and is built on a 60° short-block. Of note is t:he simplicity of the said short-block.
Figure 4, demonstrates again the simplicity of the short block of this DOHC motor, with 4 V/H; the height, complexity and no doubt its costs - are all in its cylinder heads.
It is also produced by BMW.

- 3 -ATTAINS OBJECTIVES FOR OHV ENGINES
AND
HOW ARE THEY ACHIEVED
As in previous submissions - ANSA, DEM and Attains New Engine Ports - the present objectives are exactly the same:
to deliver an engine of superior performance, which will be much lighter, considerably lower - and that can be produced at less than present costs.
These objectives are achieved as follows:
1. the :Lighter and cheaper-to-produce SOHC/DOHC short-block is the basis of new, proposed motors 2. although the wedge-type combustion chamber can remain as is, a narrow angle, hemi-spherical combustion chamber was selected for a higher specific output, as a combustion chamber of 1st choice 3. a pu:ahrod valve-train was selected because of its low cost and i.ts overall simplicity

4. ANSA valve trains (Prior Art) were chosen, because they deliver about 50~ lower cylinder heads and intake manifold heights, than their counterparts, which saves weight and cost

5. the new intake ports (Prior Art) were given a complete freedom to optimize their shapes, where applicable; Attains new Parallel-Flow Ports are introduced to enhance the engine's performance still further how are the objectives achieved - cont'd

6. When feasible and practical, Attains UNICAST/UNIBLOC (Prior Art) manufacturing technique of producing the cylinder head casting with the engine block - as one unit - is implemented, to cut costs, material usage and assembly expense.
ANTICIPATED RESULTS
* The new engine - say a typical mid-size V-8 motor - made out of steel, should be between 80 to 120 lbs. lighter, and be between 12 to 16 cm lower. If produced by a UNICAST/UNIBLOC
method, another 30 to 50 lbs. may be saved. The reduced materials usage/assembly costs may amount to $100 to $150 dollars.
* A lower engine height leads to lower hood-profiles - and an increased mileage on the highways.
* Less weight also means better handling, lower tire and brake pad wear - and leads, again to better mileage - or higher km/ Liter of fuel.

CHC
An SOHC/DOHC engine short-block is fitted with an add-on component called a "cradle." It holds the said engine's camshaft, its bearings, and the required number of guides for the pushrods and their tappets.
The name "CHC" stands for Central High Cam, or Camshaft, as it positions and supports the engine's camshaft centrally, and high in the engine block. The cradle acts as a bridge, spanning the opposing cylinder banks and providing all its components with a rigid support. It is bolted, or cross-bolted, to the engine block to form a solid and stable assembly.

The Cradle The cradle is essentially a hollow container, with its side-walls tapered to conform to cylinder-bank angles; for instance', if it is installed in a 90"engine-block, its sides will be angled at 45°. The top and the bottom of the cradle are provided with structural braces and supports, that are drilled and then fastened by bolts to the walls, or bottom, of the inside V of the engine, to firmly secure the assembly to the engine block.
At the front of the cradle is a gear, or a sprocket for a chain-drive, to drive the camshaft at its normal speed, which i:~ at 50~ of the crankshaft's revolutions.
Depending on the designer's preference, the cradle may close at bottom, or top - or remain completely open.
Lubrication The lubrication of the camshaft itself, its bearings and the pushrod guides is taken care of by the main oil pump and via drilled passages either in the cradle, or in the engine block, or both; in all instances the oil pressure needs to be only moderate, as there is no need to push the oil up into the cylinder heads via the engine's pushrods. The valve trains are lubricated by drilled passages in the cylinder banks, as per 'standard' SOHC/DOHC lubrication practice. - The CHC motor employs either DPR (Dry Pushrods), or Attains APR's, both of which are "dry" and "empty" (Prior Art).

The Cylinder Heads & Engine Ports The Attain cylinder heads can use either the manufacturers' own engine ports, or Attains Parallel Flow Ports, or enhanced-flow ports, like the VSP-type (Prior Art).
The number of valves in these ports can go up from 2 to 3, or even 4 valves/head.
Regardless of the type of intake port used, the Attain CHC engine employs off-set intake rockers, which allow the said port complete freedom of shape, size and direction, leading to enhanced engine performance.
All of this can be achieved on account of the "cradle", where the cam-lobes can be placed at any desirable position on the camshaft, giving the engine designer complete freedom to maximize engine performance. The exhaust pushrod/port alignment was never a problem - and remains so in this engine as well.
Due to its higher position in the engine block --and by virtue of employing ANSA Valve Train - the CHC camshaft allows its pushrods to comfortably reach the exhaust valves -- to create a hemi-spherical combustion chamber a feature, that was hitherto not possible without excessive-length pushrods, or special rockers.
Using ANSA Valve Trains, a high-performance combustion chamber is available to a single-camshaft engine with cylinder heads that are 50$ lower, than it was previously possible.

_ g -Valve Trains By their very nature, the Attain Valve Trains (Prior Art), that are proposed for the CHC Engine, are up to 50~
lighter, which in many instances may reduce the reciprocating weight to a point, where a performance of a pushrod engine may be elevated to a rank of an SOHC engine. For instance, some DPR
(Dry Puslzrods) are only 2.5 to 3.5 inches long.
An additional consideration is the use of an off-set rockier for the exhaust valves: because it must reach the valve in a place, where a short-block is usually narrower, i.e.
between the cylinder, the pushrod may 'dip' lower, even though the camshaft remains fairly low.
Figures For "CHC" Engines Figure 10, is an actual-size schematic of a "cradle", installed in a 90° V-type, SOHC/DOHC short-block; is shows how the cradle is attached to the short-block by bolts, or other means, and shows the general outline of its body with the supports for the camshaft and the pushrod guides.
Figure 11, shows a V-8 engine cross-section with the "cradle" installed in the "V" of the engine; an off-set intake rocker provides the intake port with complete freedom to assume its optimum shape.

_ g _ figures for CHC engines - cont'd Figure 12, shows a CHC motor in a 90° SOHC/DOHC
short-block, with an ORS/RRA Valve Train (please see Attains claim be7_ow) and an Attain PFP Type IB intake port (Prior Art).
Figure 13, shows a CHC cradle installed in a "closely coupled" 60° V engine block, which eliminated the pushrods for intake valves, which are actuated by rockers only. The intake port is Attains Type IB. The exhaust valves are operated by "push-links" and employ ANSA (Prior Art) Pull Springs.
Figure 14, shows a large, V-8 motor, with a narrow-angle hemispherical combustion chamber, an Attain PFP Port Type IB for the intake tract and a SIR/2 Valve Train (Prior Art).
Figure 15, is a cross-section of a (NASCAR) racing engine, with 2 In-Line Valves, at a very low inclined angle;
both valves use Attains ORC/RRA valve train (please see claim below). Both valves use off-set rockers, which allows the pushrods be pass very low in the engine. The "Vertical Stack"
intake port aims directly at the valve - as per usual racing practice.. ANSA Valve Trainsemploy Twist Coil Springs.
Figures 16 and 17 show two CHC engines of similar construction; Figure 16 is a V-8 engine, while Figure 17 shows a V-6 motor..
Figure 18, is a CHC adaptation to a 45° V block of a motocycle engine - Harley Davisdon's air-tolled twin cylinder.

VARIABLE VALVE TIMING FOR OHV ENGINES
OR
V V T / O H V
~h~.a-r»~
Two camshafts, placed vertically one above the other, the lowe~_ one driving the upper camshaft, are placed in an add-on, separate component called a "cradle", in the center of an SOHC/DOHC: engine-type short-block, so that each of the said camshafts can actuate through pushrods only the intake, or exhaust Attain-type valves on both cylinder banks, allowing the said camshaft's timing, or indexing, to be changed by appropriate mechanisms to affect either the timing of all intake, or all of exhaust valves singly, or simultaneously.
Introduction The "Variable Valve Timing", also called cam-phasing, or variable-indexing, is rapidly gaining popularity, because it improves the engine's performance, the vehicle's mileage and it reduces emissions. While it is very desirable - it also adds a lot of cost to an engine, as a DOHC (Dual Over Head Camshafts) becomes rnandatory. Each set of valves - in each cylinder bank --must have its own camshaft to effect a 'cam-phasing' and then both banlts must work together in 'unison' - The VVT mechanism and its operation is not discussed here at all.
Many excellent engines on this Continent are the OHV, single-camshaft types - but the 'Cam-Phasing' Technology has eluded them so far. - Attain's proposed VVT/OHV Camshaft Location can now change all that.

The Essence Of Attains Proposals Attains new VVT/OHV camshaft locations resolve the above shortcoming by extending the CHC concept to two camshafts, positioned vertically one above the other, so that the intake valves and exhaust valves in both cylinder banks are actuated by a separate camhaft.
The lower camshaft is driven by a chain, or a reduction gear at 50~ of the crankshaft speed, and a second set of gears is driving the camshaft above the first one at the same speed, on a ratio of 1:1. Actuating Attain valve trains through Attain pushrods (either the DPR, or APR's - Prior Art), the lower camshaft actuates all intake valves - and likewise, the upper camshaft actuates all exhaust valves of the said engine. -Thus, each camshaft's indexing, or phasing can be regulated by the apprc>priate mechanisms attached in front of the camshafts -- and ahead of the chain-drive, or gears, to vary the timing for each set of valves singly, or simultaneously for both.
The Engine Block To save money and weight, an SOHC/DOHC engine short-block is employed. It retains its "native lubrication system"
and needs only cosmetic changes to be adapted for this task.
The Cradle The two vertically stacked camshafts are mounted in a "cradle", which is a bridge-like housing, fabricated out of light alloys, or synthetic materials; it provides support for the camshafts' bearings, has passages for oil supply and gives structural support to all valve guides.

Installation Of The Cradle And The Camshafts The cradle is installed into the engine's V by vertical, as well as angular bolts. E.G.: at 45° in a 90° V-block engine, to provide the entire assembly with stability and adequate support of the camshafts.
Installation of the camshafts into the cradle will depend on the type of bearing selected by the designer; if the present OHV-type bearings are used, the camshafts -- must be inserted from the front. If an SOHC/DOHC bearing types are selected with bearings caps and bolts, they will be installed from abo~re.
Valve Trains & Cylinder Heads The VVT/OHV engine uses only Attains ANSA Valve Trains and services Attains Cylinder Heads, which are nominally 50~ lowe:r~ than their 'regular' counterparts, saving weight and costs. _Cf a UNICAST/UNIBLOC production method is adopted, further weight savings will materialize.
Engine Ports The VVT/OHV engine can use either the manufacturer's original engine ports, or Attains Parallel Flow.,. or Enhanced Flow Port=s .
In either case, the engine's cylinder head heights, and the intake manifold heights are drastically reduced. - and deliver key advantages described below.

The Number Of Bearings In VVT/OHV's Dual Camshafts When contemplating dual camshafts in an engine, a comparison with a typical, single-camshaft OHV V-8 motor is in order;
* an OHV V-8's camshaft with 2 V/H has 5 bearings, plus a thrust bearing - for a total of 6, and is supports (8 x 2 =) 16 cam-lobes * a VVT/OHV engine with 2 hollow-shaft (tube-like) camshafts will also have 16 camlobes but each camshaft will have only 8 lobes, which can be comfortably supported by 3 bearings, plus a thrust bearing for each.
This means, that the additional camshaft needs only 2 additional bearings.
Rey Advantages Of VVT/OHV
1. Fully separate intake and exhaust valve cam-phasing is achieved with only 2 camshafis, instead of the 4, needed in a DOHC motor .
2. A V--Type engine needs only 2 "cam-phasing" mechanisms, instead of the 4 needed in an DOHC motor.
3. A simpler, less costly and lighter SOHC/DOHC short-block is the basis of a modern, low angle IVA° hemi-spherical combustion chamber, with a very high performance potential.

key advantages - cont-d 4. Atta:in's ultra-low cylinder heads reduce engine weight -and furthermore - open the door to a UNICAST/UNIBLOC casting method - lowering the engine weight further.
5. ANSA Valve Trains & Springs, DPR and APR pushrods reduce the reciprocating weight of valve mechanisms by 35$ to 40$, or more, elevating this pushrod engine-type to an SOHC
performance plateau.
6. Engine producers can readily use the existing SOHC/DOHC
engine short-blocks for this "new engine,"

7. A 2-camshaft engine permits a full implementation of a dual-ignition system technology, with 2 spark-plugs/cylinder, now used in the Alfa-Romeo and Mercedes-Benz automobiles: each camshaft provides an ignition trigger for a separate set of spa rk-plugs.
Figures For WT/OHV
Figure 20, show a cross-section of a V-8 SOHC/DOHC
short-block, into which a cradle with two vertical camshafts was installed; the said cradle is fastened into the"V~~ of the engine by cross-bolts. The lower camshaft actuates the intake valves - the upper camshaft all the exhaust valves; The cradle also supports all the pushrod guides, the lower reduction gear and the :L:1 gear drive from the lower camshaft to the upper one.
This is <~ 2 V/H, (In-Line) engine with ANSA valve trains.

figures for VVT/OHV - cont'd Figure 21, is a schematic of the chain-and-gear drive of the VVT/OHV engine;t:~e,lower (intake) camshaft is driven by a 1:2, regular chain-sprocket drive, which in turn drives an upper (exhaust; camshaft by a 1:1 gear set. As it is customary, the Variable Valve Timing Devices) are placed in front of the camshaf is .
Figure 22, illustrates the various options available to drive the low (intake) camshaft: it could be driven by a set of gears (Edelbrock), or by a toothed-belt, marketed by Jesel.
Figure 23, is a plan view (from the angle of the cylinder bank's deck-line, @ 45°) of the two valves in the VVT/OHV engine shown in Figure 22 above: the intake valve uses an off-set rocker arm, which allows the intake port complete freedom to shape its path to the center of the engine. The exhaust valve uses a straight-line pushrod.
Figure 24, is a schematic of the VVT/OHV camshafts, viewed from the side of the engine.
Each camshaft rotates in 3 bearings (+ a thrust bearing) and has only 8 cam-lobes, which can be located on the said camshaft at any place the design of the engine calls for, to give the intake ports absolute freedom. Should the need arise, even the center bearings could be shifted slightly left, or right., Of note is the fact, that the two camshafts need only 2 additional bearing, plus a thrust bearing - while saving two complete camshafts with 10 bearings.

figures for VVT/OHV - cont'd Figure 25, is a cross-section of 2 V/H V-8 engine with hemispherical combustion chambers and ANSA Valve Trains and DPR, or P,PR Pushrods (Prior Art).
Figures 26 A & 26 B, depict one engine, which is V-

8 motor, with hemispherical combustion chambers and SIR/2 valve trains (1?rior Art). Figure 26 A, shows the intake tract, based on a PFP Type IB Attain Port (Prior Art), while the Figure 26 B, gives details of its exhaust-side.
Figures 27 A & 27 B, are a cross section of a V-8 motor, with 3 V/H; the intake tract shown on Figure 27 A, shows a T-Bar Valve Train, in which each pushrod actuates a pair of valve~~ in Attain PFP Type V (Prior Art).
Figure 27 B, shows the exhaust-side of this VVT/OHV
engine, using an ANSA Valve Train.

THREE-CAM ENGINES
Abstract In a narrow-angle V-type engines 3 camshafts replace a set of four camshafts, when the intake valves in both cylinder banks of the said engine are actuated by an indexed CHC
camshaft from a central cradle, while the outside exhaust valves are actuated by two camshafts positioned high in the short-block of the said engine, and deliver a cylinder head structure that is 50~ lower than the equivalent 4-camshaft DOHC motor.
The Three-Camshaft Engines A Three-Camshaft engine uses the centrally located camshaft, installed in a cradle to actuate intake valves in both cylinder banks of a narrow-angle V-type engine, such as a 60~V-6, or a 'J-12 motor. Conveniently, this CHC camshaft also allows the indexing or cam-phasing of all intake valves.
The exhaust valves on the outsides of the cylinder banks are. actuated by separate camshafts, each of them placed high in the engine block. The proposed port is Attains Type III
which recxuires only one cam-lobe to open two valves. - The intake ports may be the manufacturer's own design, or Attains Parallel Flow Types.
The main advantages of the Three-Camshaft Engine are its ability to deliver a high-performance engine with only 3 camshafts and one cam-phasing mechanism, instead of the4=cams and 2 cam.-phasing devices.

three-cam engines - cont'd Further advantage is the engine's very low 'profile', which is at least 50~ lower than a corresponding, 4-camshaft DOHC motor. - which is usually quite tall, on account of the narrow angle between the cylinder banks.
Of note is the little-known fact, that many automobile manufacturers of V-6 engines have chosen a 90~short block for this type of engine - just to be able to accommodate it under the hood.
Figure For A Three-Camshaft Engine Figure 35, is a cross-section of 3-Camshaft Engine;
it is a 60°, V-6 motor with 24 valves, indicating a high-performance engine.
The central camshaft sits in a CHC-type cradle and has only 6 lobes to actuate 12 valves. This camshaft can be indexed for improved performance; the intake engine ports are Attains PFP Type IB (Prior Art).
Each cylinder bank has its own, outside camshaft to actuate -the exhaust valves; again, only 6 cam-lobes are needed to for 12 valves; the exhaust ports are Attain Type V, and the valve mechanisms are Attains T-bar, with one rocker for 2 valves - (Prior Art - on both.) TWIN-SADDLE CAM
Abstract Two camshafts, placed horizontally side-by-side are installed in a separate component called a twin-saddle, which is made out of light alloys, or synthetic material - in the middle of a narrow V-type engine block, actuate two separate sets of Attain-type valve trains, one in each cylinder bank of the said engine, while the said camshafts are driven either by a common central ~~ear, or a chain-drive and deliver a cylinder head that is 50~ lower than its SOHC counterpart.
The Twin Saddle-Cam This Twin-Saddle camshaft location is well-suited for a narrow-angle V-type engine, such as a 60°, V-6 engine; the single camshaft serving each cylinder bank of the said engine may be used to actuate in-line valves, or valves for a hemi-spherica_L combustion chamber engine with short push-links on the outside of the said engine block - where the exhaust valves usually are.
Figure For A Twin-Saddle Cam Engine Figure 40, shows a Twin-Saddle Cam engine, which is a 60°, V-6 motor, with to 24 valves, actuated by two camshafts.
The said camshafts operate from a separate component, called "saddle", and houses two horizontally placed camshafts, which can be driven either by a central gear - as shown - or by a chain drive. Both engine ports are Attains PFP's (Prior Art.) SINGLE, or DUAL CAMSHAFTS-IN-HEAD
OR
S/CIH and D/CIH
TY~~tr~i.i-A single, or double camshafts located in the shoulders of an Attain-type cylinder head, immediately above the engine's short-block, actuate either both the intake and exhaust valves of the ANSA Valve Train, either directly, or by means of push-rods and off-set rockers, thus delivering a cylinder head structurs~ that is 50$ lower than a corresponding SOHC, or DOHC
cylinder head.
S/CIH
When a single camshaft is placed above the 'shoulder' of the engine block, at the base of the cylinder head, it can actuate the valves closest to it by means of rockers, and the valves on the opposite side of the cylinder head by means of short pushrods, that may be called push-links.
The S/CIH valve train creates an environment, which allows the use of manufacturers' own engine ports, or Attains Parallel Flow Ports on either, or both sides of the cylinder head, which itself is now about 50~ lower than a comparable SOHC counterpart.

D/CIH
The D/CIH concept employs two camshafts, instead of a single one, so the use of push-links is no longer necessary, since each set of valves, i.e. the intake and the exhaust valves have their own camshaft . As far as the cylinder head and the ports are' concerned, the results are the same: a reduction of about 50$ in height over an existing DOHC counterpart.
Figures For SCIH and D/CIH Engines Figure 45, is an actual-size image of V-8 engine with a single camshaft located on one side of the shoulder of the cylinder head. Intake valves are opened by rockers and the exhaust valves a~_e actuated by short pushrods, called push-links. The intake pert of this engine uses an Attain PFP Port Type IB
(Prior Art.) Figure 46, shows a reduced-size cross-section of a D/CIH encfiine, where the camshafts are located in each of the cylinder heads' shoulders.
Both engine ports are of the PFP Paralle-Flow Port Type (Prior Art) and the valve trains are of the PFP variety also.

ONE ROCKER SHAFT - REVERSE ROCKER ARM
OR
ORS/RRA
Abstract One common rocker shaft, with one, or two reverse rockers, allows both intake and exhaust valves to be actuated by Attain Pushrods and ANSA valve-train Components with Pull-or Twist Springs, to service a hemispherical combustion chamber with an included valve angle rangingfrom about 5° to 18° +, and creates a cylinder head that is about 50$ lower than a corresponding OHV cylinder head type.
ORS/RRA
As the name implies, the ORS/RRAis a valve mechanism that can be applied to both intake and exhaust valves, numbering from 2 t:o 4, operating from one common rocker-shaft and using one, or 1=wo reverse rocker-arms.
Reverse rocker arms are not new to the engine technology but they have been applied to a single valve, rather than both intake & exhaust valves. The case in point is the now famous Chrysler-Hemi Head, produced in the 195C~'s, and many others in Europe before. However, it is the Attain ~ Stem Valve and Atta_Ln's Pull-, or Twist Springs, that allow its application to both p_ntake and exhaust valves in a hemi-spherical combustion chamber; a regular Valve-Spring Assembly, with compression coil springs cannot deliver the desired geometry.

The ORS/RRA uses a single shaft, preferably hollow, to which both regular and reverse rocker arms are attached. The hollow shaft allows ample access of oil to lubricate the said valve train components and, in the case of Attains Twist Coil Springs (Prior Art) small containers around the said springs can serve as both dampers and coolers of the springs.
The ORS/RRA mechanism is ideally suited for Attains CHC Camshaft Location - reviewed above - because the centrally located nigh-camshaft can comfortably reach the exhaust valve on the far-end, i.e. on the outside, of the cylinder bank of a V-type engine with a pushrod. Hence, an ultra-low, hemispherical combustion-type cylinder is created, showing a height -reduction of about 50 $ .
Other attributes of the ORS/RRA Valve Train are:
1. low cost of the valve train 2. complete freedom to shape the intake ports -- without any interference from pushrods 3. potential to use Attains Parallel-Flow Ports 4. full potential to apply Attains Pull-, or Twist Springs proposed in ANSA (Prior Art) Figures For ORS/RRA
Figure 50, is an actual-size schematic of an ORS/RRA
application to a 2 V/H hemispherical combustion chamber engine.
The Reverse Rocker Arm is used on the exhaust valve. The two pushrods (Dry Pushrods, optional - Prior Art) converge to a Central High Camshaft - CHC. The mechanism uses Attain ~ Stem Valves and either a Twist Coil Spring, or a Pull-Coil Spring (Prior A:rt) can be applied here.
Figure 51, demonstrates - in actual size - the use of 2 Re~;rerse Rocker Arms, which are employed to open both the intake and exhaust valves. Both pushrods lead to a CHC camshaft.
Figure 52, depicts an ORS/RRA valve train applied to a narrow-angle hemispherical combustion chamber; the intake valve is actuated by a Reverse Rocker Arm.
Figure 53, is a plan view of the engine shown in Figure 52 above, as viewed from the plane of the engine block.
It shows the 2 pushrods leading to the One Rocker Shaft, which in this instance uses 2 Twist Coil Springs ( Prior Art) to close both valves. The ORS is supported by three bearings,, and the Twist Coil Springs show the outline of an oil container used as a vibration damper and oil cooler.

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AbStraCt An external arm (XA) pivoting from a short horizontal shaft, where is may be assisted by a secondary spring, actuates an Attain ~ Stem Valve through a tappet with a hydraulic valve-lash adjuster which is placed in the Upper Valve Guide, accommod~~ting also a main closing spring, while a Lower Valve Guide as;aures the stability of the said ~ Stem Valve.
XANTA II VALVE TRAIN
The name XANTA II was selected on account of a close resemblance to a previously claimed novel valve train, called XANTA.
The XANTA II valve train also uses an Attain ~ Stem Valve, which moves in its customary Split Valve Guide, which consists of the Upper and the Lower Valve Guides (Prior Art).
The entire side thrust of the rotating camshaft -transmitt=ed to a valve train by a cam-lobe - is absorbed by an External Arm (XA), which pivots either freely from a short horizontal shaft, or is assisted by small, secondary helper-spring. The upper surface of the XA (External Arm) is curved, i.e. moderately convex, while its underside has a small 'spur', which i~; either ground for a groove, or has a small ridge, dependin<~ on the "New Tappet" (NTA) type selected.

Rather than to assume a single function of a valve guide, in the XANTA II Valve Train the Upper Valve Guide incorporates a small hydraulic adjuster, which is contained in an small inner shell; the adjuster pushes directly against the tappet, which, in this fashion, maintains constant contact with the XA (External Arm).
The Upper Valve Guide's lower portion is a hollow tube, into which the upper end of the Attains ~Z Stem valve is pressed-.in and secured by valve locks.
As well, the Upper Valve Guides or the bottom of the valve' s lock - serve as pick-up points for a variety of Attain Springs, which may be of the Pull, or Compression-Type Varieties.
The choice of the NTA (New Tappets) will determine whether the entire valve train assembly can rotate, or not: if a spherical tappet is chosen, the assembly can rotate - the type of sprir,,g permitting; otherwise a 'key' is used to maintain the assembly in one position.
Overall, the Upper Valve Guide sub-assembly has a close re=semblance to a capital letter "H" . The basic shape of the Upper Valve Guide may be round, or oval; in the latter case a 'key' will not be necessary to maintain the valve guide in the same position.
The XANTA II Valve Train is very compact, simple, and can be Easily produced.

Figures For XANTA II
Figure 70, is a cross-section of the XANTA II Valve Train A~~sembly; it is shown here in its "double-actual-size", or DAS. - A spherical tappet is placed on top of the hydraulic adjuster filling out the inner shell of the Upper Valve Guide.
The XA (External Arm) swings from a horizontal shaft; an auxiliary spring is shown - but it is optional; the main closing spring is an Attain Twist-Coil Spring.
The entire XANTA II Valve Train Assembly is only 91 to 92 mm i:all, which is less than 50~ of Porsche's Boxster, or their just announced 1999 Model 996 - used in their 911 car; both of these, DOHC motors show a height of 205 to 210 mm, measured vertically up from the deck-line.
In the this Figure, an Attain ~ Stem Valve has a 39 mm diameter and is about 42 mm+ tall.
Figure 71, is essentially a duplicate of the valve train shown in Figure 70, but it uses a slightly tapered compression spring; its intake valve has a diameter of 40 mm, and is 50 mm tall.
The entire valve train assembly is 96 mm tall.