Strand, London, WC2A 2LL
B e f o r e :
| (1) Steven Tickner|
(2) Timothy Woodhouse
|(1) Honda Motor Company Limited (a company |
incorporated under the laws of Japan)
(2) Honda Europe NV (a company incorporated under the laws of Belgium)
(3) Honda Motor Europe Limited
Memery Crystal for the Claimants)
Peter Prescott QC and John Hornby of Clifford Chance for the Defendants
HEARING DATE: 13/14/15 DECEMBER 2001
I direct that pursuant to CPR PD 39A para 6.1 no official shorthand note shall
be taken of this judgment and that copies of this version as handed
down may be treated as authentic
THE HON MR JUSTICE JACOB
Crown Copyright ©
"All engines require a valve or port system to admit and exhaust the working gases from the cylinder and various valve arrangements are shown in Figure 1. Earlier engines had these valves at the side of the cylinder head and opening in an upward direction into a sideways extension of the cylinder head combustion chamber. The camshaft, which operated these valves, was therefore positioned at the side of the engine, adjacent to the crankcase, and therefore with the potential for splash lubrication from the crankshaft, as described in paragraphs 17 and 21. Modern engines have a more compact hemispherical combustion chamber to give greater efficiency, reduced emissions, and with the valves mounted on the top of the cylinder head and opening in a downwards direction. Such overhead valves can be operated by rods and rocker levers from a camshaft in the original position, but modern designs tend to use a simplified operating arrangement, with the camshaft mounted above the cylinder head to operate the overhead valves more directly."
Mr Neale's figure 1 is as follows:
[Diagram or picture not reproduced in HTML version - see .rtf file to view diagram or picture]
"many lower rated engines, and certainly those in lawn mowers, do not require an oil pump supplying oil under pressure to provide satisfactory service lives, because the oil splash generated by the moving components, provides a sufficient oil feed rate for adequate lubrication of the working parts, including the crankshaft bearings and the cylinder head area. This oil splash is typically generated by arranging for some of the moving components to have limited contact with the oil in the sump. The contact has to be limited because otherwise various components such as the pistons and rings would be flooded with oil and be unable to prevent excessive amounts of the oil from reaching the combustion chamber."
This is not true for higher rated engines, such as those used in motor cars. For these you need an oil pump - mere splashing will not be enough. Mr Neale explained why:
"The engine may be running at 3,000 RPM, it will be firing 1500 times a minute, that is 25 times a second. You would therefore have a very rapid fluctuating high load being applied 25 times a second to the shaft. The way in which that is carried is not so much by this relatively simple mechanism but another one, which is known as a squeeze film which is that it takes a certain amount of time for the oil to be squeezed out under a high load. Therefore, for these very short periods of time such as occur on an engine crankshaft you can get a very high load capacity because of the effect of the time it takes to squeeze out the oil. But the important point is that, for that to be effective 25 times a second, it is essential before the load is applied the next time that that oil film is fully filled with oil. Now, that is the reason why we require a pressure supply on more highly rated engines: it is to fill that space to be ready to carry the high load that will occur each time the engine fires."
Mr Neale caused to be conducted an examination of a number of small 4-stroke engines on the market just before the priority date. It showed that none of them below 6kW in power used pressure lubrication - all lubrication was by splash from a sump promoted by moving components. 20 of these engines had side valves; the remainder were overhead valve engines. None, however, were overhead camshaft engines.
The Teaching of the Patent
"This invention relates to lubrication systems for internal combustion engines. Such engines have been established for over 100 years, and there has been no fundamental change to their lubrication system over the years. Thus, it is traditional to provide an oil lubrication system in which a separate oil pump is provided for circulating the oil to the various moving parts thereof.
An object of the invention is to provide a lubrication system in which oil is circulated without the need for a separate pump."
"According to the invention, in an internal combustion engine comprising a crankshaft and an associated oil sump, a camshaft in a cylinder head above the oil sump, and a timing belt connecting these shafts via respective pulleys, the timing belt is adapted at all times when the engine is in operation to entrain a sufficient quantity of oil from the oil sump to lift it to the cylinder head for lubricating purposes."
I return to the meaning of this when I come to claim 1. The patent goes on:
"Conveniently, oil is returned to the sump via an oil cooler, to enable the entrained oil to be used additionally for cooling purposes."
The use of oil coolers is not applicable to small engines but is well-known in motor car engines - another indication that the concern of the patent is not small motors.
"As known per se, the camshaft and crankshaft pulleys have similarly formed tooth sets, but are of different diameters to effect the timing required, and the timing belt is of an impermeable material over its width and formed with a set of teeth around its inner face for meshing with said toothed pulleys."
That is, of course true in all OHC engines which use a timing belt. The same goes for a chain. The patent then goes on to the patentee's special idea of an additional "oil pulley" which meshes with a special extra set of teeth on the other side of the timing belt:
"In accordance with a feature of the invention, an additional oil pulley is provided immersed in oil within the oil sump, and below the level of the crankshaft pulley, the oil pulley also being toothed and the timing belt having an additional set of teeth extending around its outer face for meshing with the teeth of the oil pulley, said outer teeth providing the means for entraining oil to the cylinder head.
In one form, the additional set of teeth may be formed with scoops for entraining the oil.
Preferably, said additional teeth are designed to run closely within a closed passage, whereby they act with the wall of said passage to entrap and entrain said oil.
Preferably the engine lubrication system includes a toothed pulley, the teeth of which run over a part of the rotation within a restricted passage and a belt having matching teeth which also runs for part of its movement within a restricted passage, these runs being guided to a meshing point at which oil under pressure as a result of the meshing action is available."
"Consequently, the oil is then forced through the ports 22 by its own inertia and a squashing action of the toothed timing belt engaging with the oil pulley. Oil from the oil pulley pick-up ports 17 flows out of the transfer ports 18 effectively formed between the oil pulley teeth 8, before and after meshing with the teeth 9 of the timing belt. Consequently, the outside run of this belt is filled not only with oil from the ports 22, but also by centrifugal force acting on the oil as a result of the meshing action with the oil pulley. When oil has been transferred to the outside run of the belt, it is thus forcibly lifted through the closed passage 16 to the outlet 13 in the cylinder head 15. At this point, oil under pressure is then directed, as required, through the oil gallery 14 for the purpose of lubrication and, in the case where an oil cooler is included in the system, also for cooling. When the cooling and lubrication functions are complete, oil is returned to the sump 3 via the branches 14A, 14C and 14D."
"Referring to Figure 4, and also to Figure 1, the cylinder head 15 is provided with an oil gallery 14 which is fed from the outlet 13 of the casing 10. The gallery includes a branch 14A for feed to the crankshaft big end, branches 14B for the cylinders and return via the branch 14A to the big end, branch 14C for ancillary equipment such as the engine valves and associated tappets, and a branch 14D for overflow back to the oil sump 3."
One takes it that there are 4 cylinder because there are 4 branches 14B. And, of course, the word used is "cylinders" in the plural.
"It will be appreciated that the system and modification described above have the following advantages:
1. drives and times the camshaft.
2. pumps oil to the cylinder head.
3. delivers oil to the big end bearing.
4. delivers oil to the main bearings.
5. delivers oil to the camshaft.
6. delivers oil to the camshaft bearings.
7. delivers oil through oil galleries and cooling ducts.
8. delivers oil if required to the gearbox.
9. the oil takes heat from the cylinder head and/or cylinder and returns it to the 25 sump by way of various components that are lubricated on the oil’s return.
10. acts as an oil pump and a coolant pump.
11. the oil effectively damps out mechanical noise to a very large extent, the integrated cam drive, lubrication and cooling system effectively formed being extremely quiet in operation.
12. significant gains in torque, acceleration and horse power; significant reductions in noise, cost and lost power with full lubrication of vulnerable parts on cold start up."
(1) The reference to the "additional set of teeth being formed with scoops for entraining the oil". But that is in no way inconsistent with the patentee's concept of a specially designed arrangement whereby the timing belt lifted oil up under pressure so that the whole system could be lubricated;
(2) The statement that the "additional teeth are designed to run closely within a closed passage, whereby they act with the wall of said passage to entrap and entrain said oil" begins with the word "preferably." From that word alone, says Mr Watson, the skilled man would infer that it was not necessary to have a closed passage and hence "wet the drive" is taught. But it is also Mr Watson's case that "wet the drive" is non-obvious. I cannot imagine that the single word "preferably" would teach what is said to be a non-obvious invention. And as Mr Prescott pointed out there maybe other ways of delivering oil under pressure which did not use a closed passage or extra teeth - he postulated bucket shaped teeth on one side of the belt. These would lift oil to near the camshaft pulley where some device squashed the oil out so that it was under pressure. In effect that would be moving the squashing action of the specific embodiments from the crankshaft pulley up to the camshaft pulley - it would be consistent with the inventor's concept of doing away with a separate pump by using a special mechanism involving the timer belt to develop some pressure.
(3) The third point again rests on the single word "preferably, which opens the next paragraph (which I have quoted above). What have said about point 2 applies to this with equal force.
An internal combustion engine comprising a crankshaft and an associated oil sump, a camshaft in a cylinder head above the oil sump, and a timing belt connecting the crankshaft and camshaft via respective pulleys, wherein the timing belt is adapted at all times when the engine is in operation to entertain entrain a sufficient quantity of oil from the oil sump to lift it to the cylinder head for lubricating purposes wherein the axis of rotation of the crankshaft is horizontal and wherein the axis of rotation of the camshaft is located in the same vertical plane as the axis of rotation of the crankshaft.
Validity - General
Validity - Insufficiency
“The claimants are asserting that the patent covers an engine which uses the principle of employing a rotary device for splashing oil out of the crankcase sump to wet a camshaft timing belt having teeth on one of its surfaces, so that oil is flung off the belt in order to lubricate the camshaft. This is denied. If, however, the patent does cover an engine which uses the aforesaid principle, the patent does not teach that principle. Rather, the only principle of lubrication taught by the patent is to employ a timing belt which moves closely within a restricted passageway. Alternatively (which is not admitted) the patent teaches the principle of not having a restricted passageway but using a timing belt which is provided with teeth on both of its surfaces, oil being supplied to the belt by a so-called oil pulley. Accordingly, the scope of the monopoly asserted by the patentees does not correspond to the technical contribution made by the patent”.
"There is nothing in the claim requiring that the generated hypohalite ions should be materially or substantially responsible for the biocidal action of the composition. To introduce such a requirement, as the judge did, is impermissible. In effect it is introducing, by way of construction, a requirement that the claim must be fairly based on the patent specification which was a requirement under the Patents Act 1949, but is not under the Patents Act 1977."
1. Small side and overhead valve engines without an oil pump and relying on splash lubrication alone;
2. Oil splashers for such engines;
3. Big-end lubrication under pressure is needed for highly rated engines but not for low-rated engines for which splash will do.
Step 1 - the inventive concept
I assume here that it is "splash the belt" to lubricate the head in a horizontal crankshaft OHC engine. This involves, of course, putting the belt within the engine casing.
Step 2 - the common general knowledge
This I have identified already
Step 3 - identify the differences between the cited prior art and the inventive concept
This must be done for each piece of prior art which is not common general knowledge.
Step 4 - are the differences obvious or did they require any degree of invention?
Again this must be done separately for each piece of prior art.
Fuji I and 2
"Generally in an OHC engine, an oil pump or the like is used to lubricate a principal bearing portion, a sliding portion or the like. However, particularly in an OHC engine having a single cylinder, since installation of a forced lubrication apparatus such as an oil pump costs much and is not economical, a so-called scrape splash type lubrication system is conceived, in which an oil scraper is provided on a revolutionary portion such as a crankshaft, and lubrication oil in an oil pan is splashed, thus the lubrication oil is supplied to each bearing portion or each sliding portion.
However, in this scrape-splash type lubrication system, since the lubrication oil is splashed with the oil scraper, there may be a case where the splash tends not to be even and the oil is not supplied sufficiently to a place on which the lubrication is necessary. Particularly, it is necessary to supply sufficiently the lubrication oil on a sprocket portion or a chain portion in an OHC engine with a chain drive."
"… the object of the present device is to provide an OHC engine lubrication apparatus, which catches an oil mist scraped and splashed with an oil scraper to supply the oil mist to a sprocket portion or a chain portion and can improve a lubrication performance of the sprocket, the chain and the like with a simple structure without installing a forced lubrication apparatus such as an oil pump.
In order to achieve the foregoing object, the OHC engine lubrication apparatus of the present device in an OHC engine with a chain drive, which has a structure in which an oil scraper is fitted onto a revolutionary portion within a crankcase to scrape and splash lubrication oil in an oil pan within the crankcase, is constituted such that a guide portion is provided, which is formed on an upper portion of a sprocket or a chain within the crankcase to catch an oil mist and to flow down or drop down the oil mist on the sprocket or the chain."
Q. Let us assume it has the meaning that you suggest and I really will not go back on that; there is no suggestion to use a belt, is there?
Q. And it is the same problem that I put to you about Honda: there was no body of knowledge as to using a belt for lubrication?
Q. Therefore, can you advance any reason why the uninventive person following Fuji would adopt a belt?
A. Not following Fuji alone, no.
The P25 engine
Fichtel & Sachs
Q. Could I suggest to you that there is nothing that would indicate to this man we have talked about a lot -- the notional skilled man -- nothing to suggest to him that he could dispense with that second sump?
A. No I agree.
Q. Therefore, you could not have a horizontal shaft engine using the Fichtel & Sachs idea?
A. No, you could not, but the Fichtel & Sachs idea does teach you that the moving chain provides a balance in oiliness between its two ends and that will apply whether it is horizontal or vertical.
Q. Yes. But what you do not get out of Fichtel & Sachs is that you do not need a sump at the camshaft end?
Q. And if you looked at the engine, you would see that they are clearly relying on the sump [sprocket, I think it must be, the transcript says "pointer2"] because it has the scoops?
A. (Witness nods)
Q. So there is nothing in Fichtel & Sachs to lead you to the design of the Honda GC engine?
A. No, it is a total different engine layout.
Q. I meant in terms of the lubrication?
A. In terms of lubrication. No I do not think so, except that it does prove to me the ability of a chain or belt -- particularly a chain -- to distribute oil between its two ends.
A. Which is relevant to the Honda design.
Q. Yes, but -- and this is where the sort of lawyer approach comes in -- just looking at Fichtel & Sachs, it gets you some of the way but they did not see the final step, agreed?
Obviousness - conclusion
"…in the case of an OHC engine the structure is one in which the camshaft is in a head part of the engine main body which is separate from the crankcase, and so there is the problem that the valve drive cams and least a portion of the timing valve drive system are located in positions which are distant from an oil reservoir and there is insufficient lubrication of the timing valve drive system."
“2. An internal combustion engine comprising a crankshaft and an associated oil sump, a camshaft in a cylinder head above the oil sump, and a timing belt connecting the crankshaft and camshaft via respective pulleys, wherein the timing belt is adapted entrain a sufficient quantity of oil from the sump to lift it to the cylinder head for lubricating purposes and comprising a toothed pulley, the teeth of which run over apart of the rotation within a restricted passage and a belt having mating teeth which also run for part of their movement within a restricted passage, these runs being guided to a meshing point at which oil is pressurised as a result of the meshing action”.
2.3 An internal combustion engine according to Claim 1, wherein an oil pulley is provided below the crankshaft pulley positioned to be immersed in oil within the oil sump for entraining oil therefrom or 2 having means for supplying oil to the timing belt comprising a rotatable member adjacent to the crankshaft which, in use, picks up oil from the sump associated with the crankshaft.
His argument, as set out in his skeleton argument is as follows:
“That is not a valid intermediate generalisation and adds subject matter. As granted, the patent disclosed an "oil pulley" 7 (see Fig. 2) with an arrangement of ports 17. In use, the oil is "forced" by a combination of inertia and a "squashing action" (page 47-14). The point is that oil is driven under pressure, and not just lifted, and this is entirely consistent with the interpretation of claim 1 we have urged above. But, according to the amendment, this concept is now expanded to a mere " rotatable member". It covers and is intended to cover e.g. a bladed splasher, such as is used in the Honda engines in suit. These are two different concepts: delivery under pressure vs. splashing, and there is no basis whatever for the latter in the patent as granted”.
(1) The amendment to claim 1 is allowable;
(2) The new claim 2 is allowable;
(3) The amendment to claim 3 is not allowable;
(4) The patent is not infringed.
(5) The patent as proposed to be amended (save for new claim 3) is valid.