The Akme LPG/CNG Sequential (vaporized) Gas Injection System is designed for vehicles with
advanced petrol supply diagnostics system (OBD II/EOBD), with catalytic converter
and Lambda sensors, and meets the EURO 4 fuel emission standards.
The Akme system can be adapted to fit all engines with multi-point fuel injection, as
well as sequential, semi-sequential or fullgoup.
The use of a very fast microcontroller, acting as a signal proccessor and a “smart”
controller of the output unit of the gas injectors, enables precise and instantaneous
control of the gas-air mixture at the same moment (time point) at which the petrol
ECU would inject fuel for the current cylinder.
The very precise and time-synchronized gas injection means that no difference is felt
between running on gas and petrol. There is no significant loss of power or difference
in the vehicle’s dynamics, and the vehicle offers the same acceleration when running
on gas as with petrol.
The operation principle of the Akme system bases on the petrol injection system –
separately and independently for each channel. At every moment while the engine is
running, the petrol ECU’s strategy of the fuel supply is used. The gas injectors are
controlled by means of the signals which control the operation of the petrol injectors,
which in turn come out of the current engine need (required for power and dynamics).
The vehicle with the Akme LPG/CNG Sequential Gas Injection System will continue
to meet fuel emission standards and will meet OBD II/EOBD requirements without
additional emulators.
The vaporized gas is supplied immediately in front of the valves – as in petrol system
– which eliminates the possibility of explosions (caused by accumulation of gas in the
large volume of the intake manifold).
All engine management and diagnostic functions remain unchanged.
The Akme system has an innovative algorithm, introduced by KME, for calibration of
the vehicle during a road test. In all range of loads, the gas control unit collects points
reflecting the operation of the engine on petrol and gas, creating maps of the
operations of the vehicle. Comparison of those maps makes possible a precise
configuration of the vehicle on gas, by establishing a map for gas indentical to that for
petrol.
Previously this could only be done by means of time-consuming tests using vehicle
test benches (chassis dynometer).
The gas control unit has a built-in mechanism for self-diagnosis.
Small enclosure dimensions and a mounting bracket allows a flexible
installation in the engine compartment. Te control unit may operate
with eight sections of petrol injectors and with many kinds of gas
injectors (Matrix, Valtek, Kehin, etc.). It also operates correctly
with vehicles without the full injection sequence and with
semi-sequential petrol injection, because every channel works
separately. Various techniques improving those systems are also
implemented.
The Akme system is very simple for installers to calibrate, and is transparent to the
user thanks to the automatic switching mode. If the gas tank is almost empty the
system switches automatically to petrol supply, and this is indicated by a sound signal
(buzzer).
Vehicle driver controls switching between petrol and gas and may
observe led-visualized gas tank level with sub-miniature control
panel. DIEGO bases its calculations on the petrol injection time
calculated by petrol electronic control unit. Then using current
parameters from sensors (temperature, pressure, etc.) DIEGO sets up
the correct gas injection time and controls gas valves.
The software for Windows 95/98/2000/XP allows to start automatic calibration of the system in order to
find correct parameters for the particular vehicle. Installer has also
the possibility to manually adjust many parameters and track current
readouts.
The Akme system is available in 4-, 6- and 8- channel version for 3, 4, 5, 6, 8 cylinder
engines.
We also offer OEM version for customers creating kits themselves.PC
software
Here you can find present versions of
Akme PC software.
The software for the DIEGO unit allows to monitor live parameters
like:
- open time of the petrol injectors (each one separately or average
value),
- open time of the gas injectors (each one separately or average
value),
- engine speed (RPM),
- reducer temperature,
- gas temperature,
- current fuel type (petrol/gas),
- pressure on the injector rail,
- vacuum in the engine inlet (if the additional sensor is connected
– tab “Map”),
- system supply voltage,
- oxygen sensor (lambda) voltage and state (if connected).
There are many configuration option in the device. Using the
software one may modify e.g.:
- minimum reducer temperature and minimum engine speed to switch to
gas (switching threshold),
- number of injectors (3 to 8 depending on the device type),
- source of engine speed impulses,
- gas injectors type,
- tank level sensor type,
- type of gas fuel (LPG/CNG),
- type of connected oxygen sensor (voltage and state of the oxygen
sensor is an information readout only and do not influence the
device operation).
In devices starting from 1.3b version, it is possible to set up
the conditions of return to petrol in the case of low pressure of
the gas. One may modify pressure level and the time of low pressure
recognition. It is necessary to use at least 1.3.0.0 version of the
PC software.
The
device has a built-in autodiagnosis system, which greatly simplify
finding malfunction or mistake in the installation. It monitors not
only the gas system components, but also the elements of the
original petrol system (e.g. lack of signal from the petrol injector).
Multilevel thermal and current protection allows a secure (for a
device and for the user) disabling of the system in case of external
components malfunction.
In units starting from 1.3c DIEGO operates correctly with the
traction control systems TC/ASR.
DIEGO gas injection system has a feature of automatic calibration
for a particular vehicle. To start the procedure, after verification
of the configuration options, it necessary to use option “Autocalibration”.
The device will make a several steps procedure and then will set up
appropriate parameters for the mathematical model in order to get a
corretly burned air-gas mixture. During the calibration it is
necessary to read and execute commands written on the screen.
Optimally we shall do the autocalibration wit the engine speed
around 2500 rpm.
After the procedure of autocalibration, the basic parameters of the
model can be modified by the installer. During the operation of the
device, the clearly visible point on the chart shows the current
working parameters. It is possible to enrich or lean the mixture for
the specific load segments (in this case open time for petrol
injectors) or for the entire range. Parameter “Mult” allows
modifying (with percents accuracy) the gas-air mixture with the
respect to petrol-air mixture. Parameter “Offset” allows adding a
constant value to the open time of the petrol injectors, which may
be useful e.g. to adjust for the different gas injectors.
In order to verify the correctness of the settings and ensure
that the vehicle works correctly in the whole range of the engine
loads, it is necessary to create so called “map” of the unit. Maps
are created during driving on the petrol (we treat this map as a
base) and then driving on the gas. To start the map creation process
it is necessary to connect additional pressure sensor (calibration
set) to the device and then make a road test. The device will
automatically store the point of the map. During the test it is
required to keep the engine speed around 2500 rpm (2200-2800 rpm)
and different but stable loads. The given part of the road one must
drive twice, once on the petrol, then on the gas. During the test it
is possible to see the results on the connected PC (using the PC is
not necessary). The PC software (staring from version 1.3.0.0)
allows visualization of the map points on the “modeling” tab. It can
also calculate new parameters based on the map (option “recalculate
model” on the “map” tab). This greatly simplifies finding correct
parameters of the model. It is needed to set “mult” and “offset”
parameters in order to cover the map points by the red line of the
model.
Configuration options, model and the map one may save in the file
on the disk and then load them to the device (see “file” menu).
Inside the PC software one may find a connection diagram of the
device. Using the option “print” from the “file menu” it is possible
to print it on the printer.
The interface for the programming is available in our offer. It
is exactly the same interface used for BINGO-S and BINGO-M lambda
systems.
The device is certified according to Regulation no. 67R01.
Type-approval numbers you may find
here
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