At the start, during the competition, when all the machines are in several rows lined up in front of the white line, this card is easy to get lost among the brethren. The same wheel, the usual sight for the seat and steering wheel… That’s just the engine it does not emit deafening sounds of firing, and working with a barely audible hum. The reason is simple — on the map instead of the internal combustion engine is an electric motor, powered by the familiar lead battery…
Yes, we are the first in the country electrocat (Fig. 1). It was created in Kharkiv automobile and road Institute, where he built and tested the first electric sports car and the first sports motorcycle. Family “HADI-electro” to the test and during sports competitions showed itself from the best side. So, on the electric KHADI-11E in 1973, the Union was set three speed records, one of which topped the international.
But back to the electric chart. When it was created the Kharkiv designers used ready a normal map. About how to build such maps, the magazine “modelist-Konstruktor” wrote more than once. You can take for this purpose and the standard map “Estonia K-5” or AK-2 of the Leningrad shipbuilding plant sports.
The alteration normal map in electric is reduced mainly to the replacement engine.
DC motor R-2500 (2.5 kW power, current consumption 40÷100 a, the voltage — 24V, rated speed = 1800 rpm) is attached to the rear pipe frame pivotally map, to be able to shift it into the range of 50 mm for tensioning chain drives.
You can also use the engine less power (to 1 kW), but certainly DC with serial excitation. It is desirable that the selected motor has the reverse, that is could change the direction of rotation.
Fig. 1. Electrocat:
1 — bus, 2 — disc brake 3 —battery (rear accommodation), 4. safety, 5 — anatomic seat, 6 — steering wheel 7 — foot controls and 8 tie rod, 9 — frame, 10 — chain transmission, 11 — motor, 12 — contactor.
On the motor shaft put a small sprocket (12 teeth). Large led (27 teeth) fixed on the driving axle. Both sprockets are connected to a motorcycle chain with a pitch of 12.7 mm.
Methods of attachment of a sprocket on the motor shaft depends on the design of the shaft. If it is splined, then put the sprocket directly on the shaft.
Electrical power to the DC motor is supplied from batteries of the lead type with a nominal voltage of 12 or 24 V. the Battery located behind the seat or beside the driver, is secured in the socket of a steel angle 15X15 mm. the more batteries, the longer the run without reloading. The experience of operating the electric chart HADI has shown that when a voltage of 12 V the maximum speed of the card equal to 20 km/h, when 24 V was 50 km/h.
For remote engine start is used, the contactor K-600. It works equally well as a at a voltage of 12 V and at a voltage of 24 V. If the contactor is to get will fail, it is possible to replace the powerful home-made switch. In this case you need to consult a specialist in electrical engineering, because it is necessary not only to choose the right cross section of the tire and the wires, but also to reliably isolate the switch from the metal frame card.
The electrical circuit (Fig. 2) the map is not the challenge. It has two circuit current.
The first control circuit: battery B, the start button KNP, the winding of the contactor R and the shunt Rш.
The second circuit force, which also includes the battery B, the contact force of the COP, the anchor (I) of the motor (M), reverse switch (if any) and shunt Rш.
The reversing switch is used for electric motor, with reverse. Then electrocat will be able to move forward and backward. In the diagram the forward movement corresponds to the 1st position of the contacts, ago — 2.
Fig. 2. Electrical schematic map of HADI:
KS — contact force, M — motor, I — anchor S — field winding, Kip — start button (switch), R — coil contactor, reversing switch, Rш — shunt, B — battery.
The inclusion of the electric circuit occurs when pressing the pedal “gas”, which is connected with switch KNP. The current (small current) from the battery B through shunt Rш is supplied to the coil of the contactor R. after Passing the coil, a small current closes the power contacts of the COP, and the voltage supply (100 — 200 A) from the battery gets in the armature winding I, motor windings S and reverse the switch, if there is one.
Control of the battery discharge level is performed by means of the ammeter A, which are in parallel with the shunt Rш (shunt needs to be rated at 100 A), to reduce the current passing through the control device.
The lever of the reverse “back and forth” is installed on the steering column. Rate electric chart is adjusted automatically, depending on load.
Electrocast HADI has one distinct advantage: quiet operation and no harmful emissions of exhaust gas. This opens up new possibilities kart: allows you to use for competitions covered grounds and premises. Such a direction in the development of go-karting will undoubtedly contribute to its further promotion and growth of a new generation of Junior karting.
V. ZAKHAROV, engineer