The automotive industry is trending towards cylinder deactivation to save fuel, but Honda appears to be going even further in that direction. AutoGuide reports that the Japanese carmaker is working on a true variable displacement system that can adjust the stroke of each piston.
The design, found in a patent filed by Honda at the Japanese patent office database, would allow each cylinder to change its displacement. Current cylinder deactivation systems only enable an engine to have a limited amount of different capacities. For example, a 2.0 litre four-cylinder engine which measures 500 cc per cylinder can only vary its displacement in four ways, depending on how many cylinders are firing – 500 cc, 1,000 cc, 1,500 cc and 2,000 cc.
By contrast, the new technology will enable a four-cylinder engine to essentially offer up to 15 different displacements (, with a smaller gap between each of them. The patent also included illustrations of how such a system would work on a two- and three-cylinder engine, as well as a V6.
This technology could save fuel, but could also be used to improve the engine’s efficiency – Honda introduced the Extended Expansion Linkage Engine (EXLink) concept in 2001 (which culminated in the mass production of a Household Cogeneration Unit in 2011) that used a similar technology to extend the expansion stroke in relation to the intake stroke, increasing the work performed by the engine while using less fuel.
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my vios running 3cyl..cabut the spark plug cable and nozzle socket of 1 cyl..SAVE FUEL
Proton also got patent, but their patent is a blueprint of “How to get another RM1.5 billion from Malaysian rakyat in 1 years time”
All car companies want to buy this secret patent blueprint. Cause they too want to gasak RM1.5 billion from their governments.
A boring comment
Jonathan Lee, this is NOT a variable cylinder displacement tech. This engine cannot adjust the strokes of each piston. But, it have multiple stroke length instead. What I mean is that each cylinder have different stroke length and the stroke length is fixed. This mean that the crankshaft throw radius of for each cylinder differs slightly.
So, you could have 15 different combination of active cylinder displacement instead of 4 in conventional engine when we control the firing.
damn son…i can’t like my own comment more than 20 times…it says “error- you are voting too often”
Funny. Each person can vote 20 times. That’s how BN win lol. Good job jibby.
*yawn*
The boring Samy no life copy and paste every post
Variable displacement. How much road tax to pay?
Obviously the highest displacement combination :)
Boss. Variable displacement means each cylinder will have different capacity. 2 cyls at maybe 1000cc, another 2 at 250 cc for low speed driving. Total = 2.5l, that’s the road tax you’ll have to pay. Obviously road tax should be emissions-based but our JPJ is outdated.
?
i thought honda gonna varies the stroke.
assuming 4cyls of same bore diameter, with displacement at max is 2.4L (=600cc/cyl).
with varying stroke, the engine could run as 2.0L (=500cc/cyl) or 1.6L (=400cc/cyl).
that variable length Rx in the sketch tells the story.
R2>R3>R1>R4
nope, the drawings shows what ollie says…the Rx is fixed…
this engine does not have variable displacement. it is fixed displacement. This engine is meant to be used with cylinder deactivation technology.
so in My, it’ll be taxed according to the highest cc (longer stroke), rite?
Honda also have a patent for AVTEC – a continuous variable valve timing and lift control since 2005 but it is still no in production. In fact, Mitsubishi’s latest MIVEC 4B1 engines already incorporate the continuous variable valve timing technology.
I wonder if this patent from Honda will ever find its way into production or remain a footnote in history just like the AVTEC
Toyota VVTi is already continuous variable since early 2000, indicated by i meaning intelligent. The previos 3 stage valve timing from the 1980s is known as VVT.
Toyota ‘s VVTI (variable valve timing) has only 2 config of valve timing similar to Honda’s VTEC, Mitsubishi’s MIVEC, etc. It is NOT continuous valve timing like the AVTEC. In simpler terms, it’s like comparing a 2 speed gearbox to a CVT
Vtec doesnt alter valve timing. It changes valve lift, hence dual lobe cam shafts.
AVTEC is continuous *lifting*. Simlar tech for Toyota would be Valvematic, see Noah or Wish.
Just that AVTEC hasn’t been in production yet.
*New* MIVEC is just continuous phasing/timing without lifting. For short, dual VVT-i or dual CVTC.
While the *old* MIVEC was nothing but i-VTEC => continuous timing/phasing with 2-stage lifting.
meanwhile in malaya, perodua is offering a two tone colour and a sporty bodykit as a facelift….
#whoneedsinnovation
#no1carinmalaya
Honda–variable displacement technology
Toyota–Double VVTI
Mazda–Skyactiv tech
And…..surprise…surprise…Protong…SYIOK SENDIRI tech
And dun forget P2- Nirvana afterlife tech. Gerenti terus masuk
You can’t be more wrong. Proton can have every tech.
In a few years, Proton get to rebadge any of them, just like how we can have Vtec in our Perdana.
Proton have rebadge tech. So they can just have any tech they wanted.
Unluckily the only tech they didn’t apply rebadge tech is the power window tech.
So to dumb this down, This is basically “VTEC” using the crank instead of the camshaft. Same principal,
Would be interesting how they get this to work reliably…. VTEC runs the cams without much loading (just the valve springs), but the crank is subjected to a lot more forces.
But I’m actually more interested in something that Honda isn’t mentioning. One that is even more important that Variable displacement.
The system could/should also be designed to provide Variable Compression ratios.