CA2267882A1 - 'arvs' or attain's rotoport valve systems - Google Patents

Abstract

Filled with compressed gas, a hollow shaft, driven at 50%, or 25% of the crankshaft speed, with openings leading to bearing-like collars attached to it, distributes the said gas through sealing rings and passages in the cylinder head, to valve actuation mechanisms that open and close the valves, exhausting residual gases through similar ports into an outer air-tight tube housing the said shaft, from where the said gases are directed to the suction side of the system's gas pump.

Description

I
ATTAINS 'ROTOPORT' SYSTEMS
INTRODUCTION
What Is A 'Rotoport'?
Attains three proposed valve train systems are based on a new component called "Rotoport". What is a "Rotoport'? It is a composite word derived from a rotating port that delivers gas under pressure to simplified poppet-valve mechanisms, which can be opened by gas pressure and closed the same, or different ways.
How Does Rotoport Work ?
The 'rotoport' resembles a hollow-center camshaft with circular ports attached to it; it rotates freely in plain bearings and because it is not called on to overcome any mechanical resistance, its movement is smooth, effortless and it doesn't need much energy to perform its duty. Its operation does not involve electronic, or electro-magnetic devices at all- and can be driven by a toothed rubber belt at either 50~, or 25~ of the engine's crankshaft speed. Consequently, the installation of a 'rotoport' valve system would be economical - and would require modifications to the cylinder head only, leaving the engine's short-block as is.
The 'rotoport' simply channels gas pressure to a cylinder with a one, or two-way pistons, connected to a short-stem valve; it is called a: "Piston-Valve Assembly."
. . . cont'd II
introduction - cont'd How Applicable Are The Rotoport Systems ?
Rotoport valve systems can be applied to all 4 stroke gasoline, or Diesel-type engines, or 2-stroke-Diesels with exhaust valves, as well as to 2-stroke engines with poppet valves. In all of these engines - the number of cylinders and their end-use are transparent to the innovations.
The new valve-train systems leave the present combustion process as is, so the EPA regulations mandated to the auto-industry remain intact. The same comments apply to the use of materials:
only existing grades of steel or alloys are needed, so the investment into machinery and assembly methods also remain fully protected.
The Main Benefits Of Rotoport Systems Reduced engine weight through radically lower cylinder heads. A
lower engine that will promote better aerodynamics - and better highway fuel consumption. Possibility of casting the cylinder head with the engine block as one unit.
Superior engine performance on account of elevated RPM's -that could be on par with pneumatic valves.
Extended durability and lower production costs/unit.
Rotoport Systems can take full advantage of variable valve indexing as well as variable valve lifts.
. . . cont'd III
the main benefits - cont'd In all current combustion engines using poppet valves, their opening/closing is entirely dependent on one, or more, mechanical components. However, the valves in a rotoport system are actuated by high-pressure gas (and its release, and/or vacuum,) Consequently, there is a mechanical "disconnect" effect that is evidenced in - at least three cylinder head design areas:
a) valves - from 2 to 5/head - can be aimed at the combustion chamber at any angle that optimizes combustion, or engine performance; therefore, they can be asymmetrical.
b) radial valves, intake, exhaust, or both, can be used in any desired disposition, or mixed, with item a) above c) the distinction and /or, advantages of DOHC vs. SOHC engine-types becomes blurred: a DOHC engine owes its mechanical advantages to its very low valve-train reciprocating weight --(direct engagement) - when compared to an SOHC motor. In a rotoport-type motor the advantage of a DOHC valve train does not exist. All piston-valve assemblies (see below) are opened by gas and an SOHC engine is just as effective as the DOHC motor.
The only mechanical component is a short valve, attached to a piston and is extremely light and simple.
In all three systems presented - the valve-lash adjustment mechanism has been eliminated - because - it is simply not required.

IV
DESIGN OBJECTIVES OF THE ROTOPORT VALVE SYSTEMS
1. Create a lighter, smaller and lower engine of enhanced performance with a simplified valve train and generate attractive economies in production.

2. Reduce the engines' cylinder head heights by at least 50$ so that future motors could be cast as one unit: engine block with the cylinder head, which will further reduce the engine weight.

3. Replace the camshaft with a lighter, more energy effficient mechanical device and eliminate many components from the present valve trains.

4. Increase engine's RPM potential in racing engines to exceed today's level of 18,000 in Formula 1 motors and allow 'street motors' to run comfortably up to 10,000 RPM, if needed, while taking advantage of the proposed technology.

5. Lower internal engine friction by reducing the 'Rotoport' revolutions from 50~ to 25~ of the engine's crankshaft speed.

6. Carry forward and apply the 'variable indexing' technology to the Rotoport applications - and amplify it through the use of lower RPM's vis-a-vis the crankshaft speed, as per point 5. above.
. . . cont'd V
design objectives - cont'd

7. Expand the domain of 'engine management' by an additional 'dimension', which allows a variable valve lift along with a continuous modulation of valve-timing.

8. To save weight and cost, make the 'rotoport systems' applicable to paired valve configurations, in which one mechanism operates two valves.

9. Make full use of Attains Parallel-Flow Ports in the Rotoport applications.

10. To save cost and improve reliability, minimize the use of electronic and electro-magnetic devices in the Rotoport applications.

11. Allow the individual valves - and their immediate mechanism-to be arranged at any desirable angle toward the combustion chamber.

12. Make all valve trains completely independent of the intermediate mechanical devices that operate them.

VI
ATTAINS THREE ROTOPORT VALVE SYSTEMS
1. Pressure-Open & Pressure-Close System G~3s pressure opens and closes the valve. The rotoport directing gas over-and-below a piston in a dual-chamber cylinder;
pressure from opposite sides are also released by the rotoport.
System is applicable to single and paired valves, as well as to Parallel-Flow Ports.
2. Pressure-Open - Vacuum-Close System Gas pressures and their release from a valve-actuating cylinder are directed by a rotoport but the closing of the valve is accomplished by a separate vacuum cylinder, with a constant negative pressure. This System is best suited for 'paired-valves', which favour the disposition of the gas-pressure and gas-vacuum cylinders.
3. Spring-Return - Gas Open System (SRGO) Valves are opened by gas pressure fed into the cylinder, overcoming the resistance of a pull-spring (Attain), or other type of spring. Once the gas pressure is released by the rotoport, the spring takes over and brings the valve into a closed position. - This System is intended for 'street engines', where a maximum speed of about 10,000 RPM's is more than adequate.
The latter two Systems are adaptable to variable valve-timing (indexing) as well as variable valve-lift systems.

rotoport - cont'd Rotoport's Outer Shell Tine Rotoport turns inside an outer shell, being separated from it by sealing rings described below.
The outer shell is a two-component, air-tight vessel, or casing, firmly bolted together and then fastened to a solid portion of the cylinder head. The periphery of the outer shell contains openings that align themselves to pressure and pressure-relief ports, leading to the valve-actuation mechanisms.
Rotoport's Sealing Rings Since the outer shell - consisting of two, nearly indentical halves - will have two seams, the sealing ring is seamless and slips over the rotoport, which assures its smooth passage and prevents the rotoport from premature wear and loss of pressure.
The sealing ring will have as many openings in its body as they are ports in the outer shell, with which it must align itself perfectly. A notch on the outside of the ring fits into a opening in the outer shell, which prevents its rotation.
Near its left and right edges, the sealing ring is provided with a groove, that accommodates a circular seal, or an expandable ring, similar in appearance to a piston ring. The function of these is to prevent leakage of high-pressure gases to the outer shell.
. . . cont'd rotoport - cont'd The Rotoport - The Inner Component Tne hollow shaft of the rotoport is fed with high-pressure gas (nitrogen) through one end of the shaft, or tube. Holes in the shaft itself travel through the port passages of the rotoport component, from where they go through the sealing ring, the outer tube - and then into the pressure port of a valve actuation mechanism. The gas pressure opens the valve.
Toward the 'valve-open-event', the turning rotoport begins to open a pressure relief port - and the gases are now exhausted by an exit port, back through the sealing ring - and are evacuated through a relief port into the outer tube.
So that the released gases can travel from one rotoport to another - and eventually be collected at one end of the outer shell - each rotoport has transfer passages drilled into it, to facilitate the movement of gases in a longitudinal way. The exhausted gases are then fed to the suction-side of a gas pressure pump.
The pump compresses the gas and feeds it under pressure into the hollow shaft of the rotoport - thus completing the operating cycle.
The number of openings in the rotoport is determined by the type of system (i.e. 1, 2, or 3), the number of valves being operated by the rotoport - and the speed of the rotoport rotation.
. . . cont'd rotoport - cont'd To actuate one valve in System 1, for example, there must be two pressure and two relief ports for each 360° of rotoport rotation - if the device is turning over at 50~ of the crankshaft speed. Should the device rotate only at 25~ of the engine speed, twice as many openings will be required.
In Systems 2 and 3, only half of the ports, or opening are needed, because the valves are closed by different means. -Additional functional details will be enumerated in the description of the individual Systems.
Lubrication Of The Rotoport As the rotoport closely resembles today's camshaft, its lubrication will be similar as well: oil under pressure is fed to the sealing rings, from where it will feed the surfaces of the rotoport proper.
Since the rotoport does not need to overcome any mechanical resistance - like spring pressure and built-up friction -the functioning of the rotoport should be marked with longevity and durability.
The Bearings Supporting The Rotoport In a typical V-8 engine, a rotoport serving both the intake and exhaust valves would require 5 bearings. It would, in fact, resemble an SOHC camshaft. The end-bearing would be a thrust bearing, which could combine with a coupling for high-pressure gas.
. . cont'd rotoport - bearings - cont'd Should each row of valves require a separate rotoport, then the installation would parallel a disposition of a DOHC
configuration.
How Is The Rotoport Driven ?
One, two, or several rotoports can be driven by toothed rubber belts off the crankshaft main pulley. An alternate arrangement could be a chain drive. Both of these methods are purely mechanical and do not require any elecronic devices.
Variable Indexing Of The Rotoport Variable valve timing, or indexing of the camshaft, which is very popular and effective - is equally available to the rotoport and similar devices, whose slip-angle is governed by hydraulic mechanisms - can be employed here as well.
When the rotoport is turning over only at 250 of the crankshaft's speed, the variable indexing would be twice as effective; therefore, the angle has to bereduced by 50~, which may reduce the cost of such devices.
Variable Valve Lift Certain rotoport Systems offer also variable valve lift. They will be detailed below.
Application Of Rotoport With minor modifications, the 'rotoport' is used in all 3 Systems proposed by Attain.
. . cont'd application of rotoport - cont'd As well, the rotoport valve systems can be applied to to single and paired valves.
Furthermore, they can be used in Attains Parallel-Flow ports, either in single, or dual-valve applications.
Gas Pump, Tank & Auxiliary Equipment Tize nitrogen gas - most-likely substance to be used in the proposed systems - is compressed by a pump and maintained at a predetermined level at all times.
The pressurized gas is fed into the hollow shaft of the rotoport.
Gases exhausted from the piston-valve assemblies into the outer tube of the rotoport are returned to the suction side of the pump.
High- and low-pressure valves are needed to maintained the desired pressure level in the system, along with a tank, or reservoir.

FIGURES FOR 'ROTOPORT' Figure 1 - Schematic Of Rotoport Valve Operation Pump, Item 1., delivers gas (nitrogen) under pressure through a circular seal into the hollow shaft of the 'rotoport', Item 2., to which four, rotating ports, are attached, delivering pressurized gas to four piston-valve assemblies, Items: 3, 4, 5, and 6.
To illustrate the functioning of the device the four 'rotoports' have various ports, namely: Item 3. is open for pressurized gas to enter the cylinder of the piston-valve assembly, while No. 4.
and item 6., are letting the gases to be exhausted into the outer tube, Item No. 7. Port No. 5. is closed but the rotoport shows a "transfer port", which lets the exhausted gas to travel laterally in the tube, from where they are collected and delivered by a return tube, Item 8., to the gas pump, Item 1.
Item No. 9., shows the 'blind-end' of the rotoport, its seal, bearing and the wheel pulley, which is engine driven by Item No.
10, which could be either a toothed rubber belt, or a chain, leading to the engine's crankshaft.
The 'rotoport' may be provided with a variable-index device, similar to those used on variable valve-opening mechanisms in today's car; these would be incorporated in Item 9., but are not shown Please note, that the 'rotoport' can be driven either at 50~, or 25~ of the crankshaft's RPM's.
. . . cont'd _ g -rotoport figures - cont-d Figure 2 - Elements Of Piston-Valve Assembly A short-stem valve is attached to a piston, and is called the Piston-Valve Assembly, Item 1., and moves in a cylinder, Item 2.
The 'rotoport', Item 3., rotates in its outer enclosure, Item 4., and opens/closes ports Item 5., as required to move the piston up and down in the cylinder.
Ttie piston, Item l., acts also as an upper valve-guide and stabilizes the assembly in its upper region, while a lower valve guide, Item No. 6, has an oil seal and stabilizes the assembly 's lower end.
Lubrication for the piston is provided by a channel in the cylinder, Item No. 7.
It should be noted, that the functioning and mechanical details of the piston- valve assembly will vary from system-to-system in the 3 proposed models by Attain; additional details will be provided in the appropriate places.
Figure No. 2, should be considered a generic illustration of the valve-actuation principle proposed in the 'rotoport system.' . . . cont'd - g -rotoport figures - cont'd Figure 3 - 'Rotoport's' Outer Shell Tne upper Image A, provides a side-view of the rotoport's outer shell, as it is split along its vertical lines, Item No.l. The right-hand side, Item 2., is fastened to the piston-valve assembly, Item 3., and is connected to it by matching ports, so that the valve can be opened, or closed. The outer shell is a low-pressure type of vessel, since it handles only the gases that have been expelled from the cylinders - and are on their way to the suction-side of the gas pump. Otherwise, the outer shell provides the rotoport with its outer bearings and carries the end-seals.
The Lower Image B, shows the outer shell in its longitudinal disposition, Item 4., and shows only a pair (of the several) opening required to keep both halves together: Items 5 below and above.
The vertical grooves, Item 6, are for the seals of the inner, rotoport shaft.
Figure 4 - Sealing Rings & Seals The ports of the rotoport must cross over the grooves, or seams of the vertically split outer shell; to minimize wear and assure batter sealing, a sealing-ring is proposed, that would make the rotoport's ports glide over these spots smoothly.
Each sealing ring carries with it also two end-seals and is . . . . cont'd rotoport figures - cont'd lodged firmly against the outer shell. To assure perfect alignment of the ring with the rotoport and the ports of the piston-valve assembly, the sealing ring is provided with a protrusion that falls readily into a oavity of the outer shell.
Item Z., in the upper Image A, is a sealing ring, with left and right seals, Items 2 and 3 flanking it. Item 4 shows a protrusion, which locks itself into the outer shell, Item 5.
Item 6 delineates the position of the rotoport No.6, but does not show its ports.
Image B, below, shows the rotoport in Item 7, and the sealing ring is Item 8. The 2, left and right seals, are shown as Items 9 and 10, respectively.
Figure 5 - Rotoport's Inner Components Image A is an axial view of the 3 types of ports, that are used in the rotoport's disk, or collar, which serves the device also as its own bearing. Item 1., is the rotoport's disk, item 2 -(upper and lower one) are the pressurized gas ports, for the shaft has to have openings. Items 3., and 4. are exhaust ports, by which the gases are released into the outer shell - and items 5 and 6 are the lateral transfer ports, by which the expelled gases can travel from left to right - to be returned to the suction-side of the gas pump. Item 7 shows how the device is lubricated.
In Image B, Item 8 is a gas-pressure port, 9 is an exhaust port and Item 10 is a lateral transfer port.
. . . cont'd rotoport figures - cont'd Figure 6 - Top View Of The Rotoport Item 1., represents the inner, hollow portion of the rotoport, which is fed by pressurized gas. As its rotates, its opening, or ports, shown in Item 2., line up at predetermined intervals against similar openings (ports) in the cylinder of the piston-valve assembly, item 3, which actuates the valve. Item 4., is a a transfer port, allowing the gases to travel laterally in the rotoport. The outer shell, item 5, has suction, or return channel, item 6, through which all gases return to the gas pump.
Figure 7 - Enlarged Cross-Section Of The Rotoport This Figure aims to show the disposition of the 3 types of ports present in a single rotoport, with their approximate timing and/or overlap.
Item l., is the rotoport, in which a pressure delivery port, item 2, delivers gas into the cylinder of the piston-valve assembly. Item 3. , is an exhaust port, still open but about to be closed. Item 4. is a transfer port. -The vertical split of the outer shell can be seen in item 5, and the rotoport's interface with the engine's cylinder head is shown in item 6. - Item 7., is the 'locating-pin'for the sealing ring, to keep in alignment. Item 8 shows a passage of lubrication oil to the rotoport.

ATTAINS ROTOPORT SYSTEMS

ABSTRACT
A piston attached to a short valve-stem actuates 1, or 2 valves by moving in a 2-way cylinder to which gas under pressure is admitted, or released, through appropriate passages opened and closed by a rotoport, which delivers gas under pressure through its hollow shaft either to an above, or below, portion of the said piston and releases the said gases from the opposite portion of the said cylinder just prior to pressure application, to let them escape to the outer tube of the said rotoport, from where they travel to the suction-side of the gas pump supplying the system with constant pressure.
Valve Actuation In System 1 The upper portion of an Attain ~ Stem Valve is connected to a piston moving in ,a 2-way cylinder. To open the valve, residual gas pressure is first released from below the said piston -and then applied above it. Moving freely down, the valve piston assembly comes to stop when it reaches a "bumper", that blocks its further travel.
At the end of the 'open-valve-event', the pressure is first released from above the piston - and new gas pressure is directed to the lower portion of the cylinder, below the piston.
The valve travels up and comes to a stop when the valve fully closes the engine port.
. . . cont'd

- 13 -sysrtem 1 - cont'd Rotoport Function In System 1 ~ihile rotating - over at 50~ of the crankshaft speed, each collar, or port of the Rotoport will have 4 openings: two will deliver gas under pressure to open and to close the valve -and two relief, or exhaust ports. While gas under pressure comes to the valve mechanism from the hallow center of the rotoport shaft, the gases released by the 'exhaust ports' will escape into the outer shell, from where they will be fed back to the suction side of the gas-pressure pump.
If the rotoport turns over only at 25~ of the engine speed, the number of ports will double, and will be 8, instead of 4.
Applications Of System 1 The above mechanism can be applied to single, or paired valves.
Additional Features Available In System 1 System 1 may be provided with a variable cam-phasing, or valve indexing feature, by applying to present technology to the rotoport. In fact, if the rotoport turns over at 25~, the cam-phasing feature may be enhanced.
The downward travel of valve may be 'regulated' by employing a movable stop, or 'bumper', by extending, or limiting its lift.

- 14 -Figure 10 - Piston-Valve Assembly The piston-valve assembly, Item 1., moves in its cylinder, Item 2. Because pressure is applied to both above and below the piston, the latter must be fully enclosed. The travel of the valve is limited in its down-ward stroke by a stop, Item 3.
The System 1 employs a (power) cylinder with four ports. To open the valve, the rotoport opens first the exhaust channel 4, while opening the power port, Item 5., which brings the piston down.
To close the valve, the upper exhaust port, Item 6. opens first and the rotoport opens simultaneously the power port Item 7., which brings the valve into a closed position.
Tne piston-valve assembly is stabilized internally by two valve guides: the piston acts as an upper valve guide and a short valve guide at the bottom, Item 8, with an oil seal, stabilizes the valve in the lower region. - The lower portion of the cylinder is also provided with a pressure seal, Item 9.
Figure 11 - Actuation Of Piston-Valve Assembly To illustrate the functioning of the pressure and exhaust ports, this figure shows four images with the positions of the piston in items A, B, C & D, going from left to right in a clok-wise fashion.
. . . cont'd

- 15 -Figure 11 - cont'd ACTUATION OF PISTON-VALVE ASSEMBLY

Image A
a) pressure is released from the lower cylinder, below the piston, by exhaust port EX l, Item 1.
b) at the same time, pressure port P1. Item 2., opens and feeds pressurized gas above the piston, forcing it down, all the way to a stop, or bumper, Item 3.
Image B
* pressure port P1 remains either open, or maintains sufficient pressure in the cylinder to keep valve open Image C
c) exhaust port EX 2, Item 4., begins to open, relieving gas pressure in the cylinder above the the piston d) simultaneously, pressure port P ~2, Item 5., feeds pressurized gas into the cylinder below the piston, forcing the valve up and into its seat.
Image D
* pressure port P 2., Item 5., remains either open, or maintains enough pressure in the lower cylinder portion to keep the valve sealed.
The sequence of each complete cycle is as follows:
EX1 (gas out) - P1 gas in - forces the piston down, and EX2 (gas out) - P2 gas in - forces the piston up

- 16 -figures for system 1 - cont'd Figure 12 A - Positions Of Pistons Here, the piston is shown again in its extreme positions: item 1 shows it in top, while item 2, shows it in its extreme bottom position; the four ports, previously described are also shown.
Figure 12 B - Four Openings In Rotoport To illustrate the alignment of ports in the cylinder with the 4 openings in the rotoport, this figure shows that they are both in the exact positions.
The pressurized gas ports are in the center, Items 1 and 2, while the exhaust ports, Items 3. and 4 are on the outer sides of the rotoport.
Figure 1'3 - Single Valve In System 1 Image A, is a cross-section of piston-valve assembly, Item l, being actuated by a rotoport, Item 2. Only two ports are shown but 4 are required to operate the valve.
Image B, is a top view of the piston-valve assembly, Item 3., shows the outer enclosure of the rotoport, Item 2.. the rotoport itself, Item 4 and its 4 ports, ' . . . cont'd

- 17 -figures for system 1 - cont'd Figure 14 - Paired Valves - Single Rotoport Image A shows two valves, side-by-side, called paired valves in,a side view. They are actuated by a single rotoport.
In Image B, item 1, is a rotoport, and items 2 and 3 are the piston-valve assemblies belonging to two valves. - Four channels, or ports of the rotoport, Item 4 actuate both valves but must be interconnected to perform the double duties.
Figure 15 - Valves In Attain' Parallel-Flow Ports Single, or dual valves, placed in Attains Parallel-Flow Ports, can also be actuated by the rotoport device.
The figure shows a single valve, which is actuated by a rotoport, Item 1., its System 1 piston-valve assembly, Item 2., being completely concealed in the streamlined parallel-flow port, Item 3.

- 18 -cvcmz~a ~
T D C mD T !'m A set of two adjacent valves connected by a cross-bar is provided with two valve-actuation devices comprising two pistons placed inside two cylinders, which are connected to the ports of a rotoport, and one centrally located vacuum cylinder with a piston attached to the said cross-bar keeping both valves closed till gas under pressure is admitted to both said cylinders and overcomes the pulling force of vacuum cylinder for the duration of the open-valve event, after which it is released and both valves are closed.
Valve Actuation In System 2 System 2 is intended for 'paired-valves', where two adjacent valves operate in unison, so to speak. The two valves are connected (mechanically) by a cross-bar; in its center - is a vacuum cylinder, which lifts up both valves into a closed position.
Above each stem of the valves is a one-way cylinder with a piston. To open the valves, gas pressure is applied to both cylinders - and both valves are opened. It should be noted that the gas pressure must by higher than the pulling force of the central vacuum cylinder.
At the end of the 'open-valve-event' the gas pressure from the two cylinders is released - and the constant vacuum force of the central cylinder takes over, and closes both valves.
. . . cont'd

- 19 -system 2 - cont'd System 2 employs two pneumatic systems: to open the valves a gas pressure is employed - and to close the valves, a secondary, vacuum system is needed. The latter is a passive system, unregulated, in that the force of the vacuum is applied constantly to the vacuum cylinder in the middle of the two adjacent valves.
Rotoport Function In System 2 The rotating collar of the rotoport has only two ports: one delivers gas pressure to open the valve, the other releases it, to allow the vacuum system to take over and to close the valves.
As in System 1, gas under pressure is delivered through the hollow shaft - and the released, or exhausted gases are let to escape into the outer shell. - The rotoport in System 2 can turn over either @ 50~, or 25$ of the crankshaft speeds.
Additional Features Available In System 2 Both the variable cam-phasing and the variable valve-lift features are available in System 2; In fact, the latter could figure prominently here, because a 'bumper' , or a stop for the valve-lift can be conveniently located below the vacuum cylinder thus controlling the travel of 2 valves with one device.
...... cont'd

- 20 -Figure 20 - Piston-Valve Assembly In System 2, the piston-valve assembly is simplified by the fact that only two ports are need in the rotoport and in the cylinder housing the piston. Gas pressure opens the valve and the pressure is released by an exhaust port but the closing is accomplished by a vacuum cylinder. For best performance, System 2 should be used only in paired-valve configurations, with 2 valves being connected by a cross-bar.
Item 1., is the cylinder, the gas pressure and exhaust ports are items 2 and 3. The piston, Item 5 is open at the bottom; the cross-bar, item 6 connects two valves. Item 7. is the lower valve guide with an oil seal. Optional piston ring - Item 4.
The variable valve-lift is possible in System 2, and is placed under the cross-bar. Please see Figure 21.
Figure 21 - Paired-Valve Operation Image A shows the centrally located vacuum cylinder, Item 1., which returns both valves into their seats by means of a cross-bar, Item 2. Both valves are opened by gas pressure from the rotoport; the 2 valves are Items 3., and 4. - Item 5., is a stabilizer, which includes a movable stop, Item 6., which when moved hydraulically could either shorten or lengthten the travel of both valves. Details of this mechanism are not shown here.
. . . cont'd

- 21 -figure 21 - cont'd Image B, shows the rotoport, Item 7, how it operates the 2 valves, Items 8., and 9. Item 10., is the vacuum cylinder.
Figure 22 - Paired Valves In Attains Parallel-Flow Port The vacuum cylinder in between a couple of valves, operating in Attains Parallel Flow Ports, brings back both valves to a closed position by the force of a vacuum.
Item 1., shows the vacuum cylinder, Item 2 is the cross bar.
Both valves, Items 3 and 4, are provided with their own piston-valve assemblies, under the control of a rotoport.
Item 5 shows a cross-section of piston-valve assembly in the left-hand valve only.
The details of the rotoport and the vacuum lines, or pumps are not included in this image.

- 22 -~~~m~~
ABSTRACT
A valve-actuation mechanism comprising a piston attached to an Attain ~ Stem Valve and fastened either to a pull-or a compression-type spring, is moving in a cylinder into which gas pressure is first admitted by the rotoport and maintained there till the end of the valve-open event, and subsequently exhausted through a relief port, which allows the force of the extended, or compressed spring, to bring the valve into its seat and to close it.
Valve Actuation In System 3 An Attain-type valve - with a very short stem - referred to as a "Z Stem Valve" - is attached to a piston that moves in a cylinder. The valve-and-piston are named a "piston-valve-assembly". Various types of Attain-type springs can be attached to the piston either from above, or below it.
Whether the spring is placed above, or below the piston, the prime design objective is to have a valve with a shortest stem possible, to minimize the reciprocating weight of the piston-valve assembly.
The type of springs employed in the system 3 could be: a pull-coilspring, wafer pull-spring, or ypsilon (compression) spring, a pyramid pull-down spring, etc. Some of the springs can be also . . cont'd

- 23 -system 3 - cont'd mounted externally, outisde of the power cylinder.
Just like the two previous sytem, System 3 does not require any valve-lash adjustment mechanism.
Rotoport Function In System 3 In System 3, the rotoport's function is almost identical to that in System 2: it is limited to open the valve by delivering gas under pressure - and then to release it.
The return spring pulls the valve shut, Applications Of System 3 Due to the presence of a spring, the System 3 mechanism cannot be expected to operate in engines turning over at 12,000 RPM's, or higher. - However, its light weight and simplicity should deliver adequate performance for 'street engines' operating up to 10,000 RPM's. Both single and paired valves are eligible.
Additional Features Available In System 3 Variable cam-phasing and variable valve-lift may be easily installed in System 3, enhancing its performance.
. . . cont'd

- 24 -Notes:
1) the piston-valve assembly in the System 3 is very similar to the one used in System 2; please see Figure 20. - The cylinder uses only two ports and the valve is returned to its seat by an Attain-type spring, attached either below the piston, or on the ceiling of the cylinder. These springs were proposed in Attar s ANSA and DEM submissions.
2) for the sake of clarity, the majority of figures are presented in the "double actual-size", or DAS format so that by a 50~ reduction they represent real-life components, while providing better definition of details. In particular, the sizes of the valves should be noted, as they affect the height of the cylinder heads.
Figure 30 - Ypsilon Compression Spring An ypsilon compression spring is attached under the piston and mounted in such a way, that its coils do not interfere with each other in compression; the piston is Item l., the spring is Item 2. A two-channel rotoport, Item 3. actuates the valve by pushing the piston down gas pressure. When the pressure is exhausted, or released, the force of the spring returns the valve into its seat. The actual valve size is 35 x 52 mm long.
. . . cont'd

- 25 -figures for system 3 - cont'd Figure 31 - Pyramid Compression Spring In piston, Item 1., a pyramid compression spring, Item 2., is mounted inside it. The rotoport. Item 3, actuates the valve in a similar fashion as in Figure 30. - The valve size is 35 x 40L.
Figure 32 - Pull-Coil Spring A pull-coil spring, Item 1., is suspended from the ceiling of the cylinder by means of clamps, or attachments, Items 2 and 3.
The bottom of the spring is fastened to a center-piece of a two-component piston, Item 4. The rotoport, Item 5., actuates the valve by admitting gas under pressure into the cylinder and then releasing it. In order to reduce the inside volume in the cylinder, a cone-shaped cavity fills the center of the cylinder and reaches down from its ceiling. The valve is 36 x 46mm long.
Item 6., is the cavity.
Figure 33 - Two Component Piston The center piece of a two-component piston, Item 1., is provided on its periphery by threads, Item 2, that can be screwed in into the outer diameter of the piston, Item 3.
The center-piece also has a valve-lock, Item 4., to which the valve, Item 5., is secured but is allowed to rotate, if so desired.
The upper portion of the center-piece, Item 1., has also a provision for a bolt-on clamp, Item 6., which secures the bottom of the pull-coil spring, Item 7. to the center-piece, Item 1.
. . . cont'd

- 26 -figures for system 3 - cont'd Figure 34 - Wafer Pull-Spring In Image A, an Attain z stem valve - 35 mm diameter, and only 40 mm long, Item l., is attached to a piston, Item 2. The crown of the piston is provided with rising flanges, or ears, that are pierced with a short rod, Item 3., to which the bottom of a wafer Pull-Spring is looped. The expansion spring, Item 4., is also secured to the ceiling of the spring dome, Item 5., containing four locks, Item 6, that are locked to the open-end of the spring. Item 4. O~.zly a half of the spring is shown.
While this figure shows a dual Wafer Pull-Spring, the mechanism could well operate with a single expansion spring.
Image B, shows the details of the spring attachment: Item 7, shows the four spring terminations, that are secured in the round cap, Item 8, of the power cylinder.
Item 9, shows the rising flanges,(two) - and the rod, Item 10, that secures the two springs to the crown of the piston.
Figure 35 - External Pull-Coil In this mechanism the rotoport, Item 1., is directly above the piston-valve assembly, Item 2. A relatively long valve - 40 x 57 mm - Item 3. is locked-on to the piston and below this lock is a modified spring-cap, Item 4, that reaches out beyond the diameter of the cylinder, Item 5., to engage an external pull-coil, Item 6.
. . . cont'd

- 27 -figures for system 3 - cont'd Figure 36 - System 3 In A Parallel-Flow Port A nearly 'square' - 30 x 31 mm long valve, Item 1, is attached to a piston-valve assembly, Item 2., completely enclosed by a valve-shroud, Item 3.. in an Attain Parallel-Flow Port, Item 4.
A pull-coil spring, Item 5 is attached to the piston of the piston-valve assembly and then to the ceiling of the valve shroud, Item 3, as shown in Item 6.
The rotoport, Item 7., actuates the valve by means of 2 channels.
Figure 36 shows the operation of a single valve but a 'paired' valve operation is also well feasible.

- 28 -'PROFILES' OF COMPLETE ENGINES
At least five of the sated design objectives of the Rotoport Valve Systems can be seen in the 'profiles of complete engines' submitted in this section. - They are:
1. the ultra-low cylinder-head heights (referred to as MCH, i.e.
Maximum Cylinder-head Height) 2. anticipated reduction in engine weight 3. possibility of a Unicast/Unibloc construction method, in which the cylinder-heads are cast with the engine block 4. ability to use valves at various, "asymmetrical" angles 5. possibility to use radial valves (with No. 4, above) 6. clear lack of any advantage by using DOHC valve trans vs.
SOHC types, due to a "mechanical disconnect" present in the Rotoport Valve Systems. (SOHC is: single-overhead camshaft and DOHC is Dual Overhead Camshaft.) In previous Attain patent submission claims have been made to the effect that the cylinder heads were at least 50~ lower than their original counterparts. A true, A to B comparison can't be made, because such enginesaren'tin existence. Since the Rotoport Valve Systems are a 'novelty', such a comparison is not possible.
Therefore, the only point of reference is the engine's cylinder bore, e.g. a diameter of 90 mm, etc. The MCH (see above, please) can then be fererenced to the engine bore.
As a general rule the cylinder head height is considerably less than the engine's bore, e.g. 70 mm of MCH vs. 90 mm of engine bore.
. . . cont'd

- 29 -Figures For Complete Engines Figure 40. An SOHC type, with 2 to 4 V/H, suitable for Systems 1, 2, or 3. - Included Valve Angle (IVA°) is 26°, bore is 90 mm but the MCH (Maximum Cylinder-head Height) is only 70 mm.
A single Rotoport actuates all valves.
Figure 41. Also an SOHC motor with an IVA° if 18; bore is 90 mm and the MCH is only 60 mm. Suitable for Systems 1 and 3.
Figure 42 (lower image). An SOHC motor, with 2 to 3 valves at 22° IVA. Bore is 90 mm. It is suitable for System 3 only and uses Wafer Pull-Springs. MCH is 75 mm.
Figure 43, represents a DOHC racing engine with Rotoports, actuating 3 to 5 valves, at 36° IVA. Attains Parallel-Flow Ports are used in both the intake and exhaust tracts; The camshafts are located just above the 'shoulders' of the engine block; their location is designated as DCIH (dual camshafts in head.). The engine bore is 100 mm but the MCH is only 80 mm.
There does not appear to be a mechanical advantage to use two Rotoports, except for reasons of exceptionally low MCH and better engine cooling.
Figure 44. A high-performance engine with a single Rotoport, actuating both the intake and exhaust valves. The intake tract uses Attains Parallel-Flow Ports, while the exhaust tract is a "regular" port; the valves are @ 34° and the engine bore is 94 mm. The engine is suitable for System 1 only.
The MCH is only 75 mm.

APPENDIX
Attains Rotoport Valve Systems make several references to previously submitted innovations, included in patent applications forwarded to CIPO at previous dates:
Item CIPO Reference Attains ~ Stem Valves Special Expansion ~Z 2,221,622 Compression Springs 2,222,979 PFP - Parallel-Flow Ports (all types) T-Bar 2,225,048 New Camshaft Locations (as applied to Rotoports) 2,227.025

Claims