A log of the trials, tribulations, and general boring stuff involved in owning an electric car... an EV conversion... a battery-only electric car... Plankton the electric 1976 BMW 2002.
Plankton's current specs
Plankton's Current Specs:
Motor: 9" Series DC, refurbished by Jim Husted in Redmond, OR.
Controller: Synkromotive
Batteries: 35 CALB LiFePo4 cells (115.5V nominal pack voltage)
Charger: Elcon PFC1500, so far only charging from house mains 110-120 AC.
Pedal: Ford Ranger TPS
-No clutch
-12V Pb-Acid auxiliary battery for car electrical (blinkers, lights, etc.)
-Generic (??) vacuum pump for brake assist (no power steering)
Monday, February 2, 2009
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I needed a way to connect the two shafts- one from the electric motor and one from the existing BMW transmission. The problem is, they weren't made to go together. The shaft from the motor is a smooth shaft with a keyway, and the shaft from the transmission is splined (the old clutch disk is splined and slid onto the splines of the tranny... well at least it used to, but I won't have a clutch). So here is the first thing I got, a Lovejoy coupling. It is basically two metal collars that slide together, with a urethane spacer in between them. The urethane allows a little bit of give if there is minor misalignment. I thought it sounded good to allow for a little misalignment. The picture shows the coupling (assembled) on the left, there is a key (for the keyway) in the center, and a collar is shown on the right. The collar, plus another, will keep this whole assembly from moving fore and aft on the two shafts. It'll be trapped.
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The shaft of the motor fits right onto this thing, but I need to mod the other half to accept the splined center of the old clutch disk. I'll have a shot of that later, it's not done yet.
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The shaft of the motor fits right onto this thing, but I need to mod the other half to accept the splined center of the old clutch disk. I'll have a shot of that later, it's not done yet.
Transmission digitizing
The tranny was already out with the motor, so I hauled it to work and digitized the bolt-hole positions on our CMM (coordinate measurement machine).
Motor arrival
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The beginning
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