[johnsiddle]

Hi Guy's

Do you think a hydraulic motor from a Lansing Bagnal Forklift rated at 67v and with the part number 4005679, Series wound continuous, would be a suitable EV drive motor?

regards John

 

[johnsiddle]

Hi John,

I assume you mean a pump drive motor. Hydraulic motor typically refers to a device using hydraulic fluid flow to produce a mechanical output.

Contrary to what was told you on the other thread, main (lift) pump motors from fork trucks can be as powerful, or even more so, than traction motors. It depends on the type of lift truck. Just because the pump motor is rated on a low time-on duty cycle doesn't mean it won't run continuously, at a lower power output. And they are often fan cooled.

The pump motor from a forklift may be suitable for an EV conversion. Typically they are unidirectional, so be sure rotation direction is correct for you. Switching rotation requires internal modification. And typically the motor will have an internal splined shaft making a coupling for a car very difficult.

Regards,

major

Thanks Major.
The one I am looking at is on Ebay now, it is rated as continuous and has plenty of cooling from the picture it seems to have a fan and an open cover over the brushes, it still has the pump attached so presumably I could use parts of the pump to fabricate a flange of some sort, maybe weld a plate into it...
john

 

[johnsiddle]

I have picked up a Pump Drive motor from a forklift it isn't the one I was hoping to get but hopefully it will be suitable.
It has a female star shaft but I have the star bush that was fitted to a keyed taper shaft on the pump assy and I hope to fabricate a shaft with it.

Also it does not have a fan fitted but I am sure I could force some air in thro the brush guard, getting the hot air out again might be a problem tho.

It measures 11in by about 8in diameter and has a good clean commutator with four sets of twin brushes.
Rated at 67V and 115Amps but only at 15min.

There are three 8mm female connectors coming through the body which are marked A, YY and Y, I understand the A means armature ( I guess) but does anyone know what the YY and Y mean they have continuity to A connected internally. The guy I got them from said it was for forward and reverse.

Anyone know for sure what the connections mean and could it be a suitable EV motor.

John

 

[johnsiddle]

Hi john,

From that info, I'd say it is a split field reversible series wound motor. The typical reversible series wound motor has 4 terminals, A1 & A2 for armature and S1 & S2 for the series field. Reversing is accomplished by reversing one or the other, but not both. This requires heavy (full motor current rated) contactors, two spdt. Read expensive.

The split series motor is actually designed and built with two independent (electrically) field coil sets. One coil set (Y) for one direction of rotation and the other coil set (YY) for opposite rotation. Now it can use a single spdt contactor or two spst. It does require additional diodes. This can be a cost savings. However you pay a penalty in series field resistive loss, perhaps affecting motor efficiency ~5%.

There are some other tricks designers can employ with the split series motor which can eliminate the reversing contactors altogether, do field weakening, and/or motor braking even with some degree of regeneration, when mated with a specialized controller.

Testing is the easiest method to verify what you have. Use a 12V car battery and jumper cables or the like. Put motor on floor or otherwise clamp it so it does not twist off the bench onto your toe. Connect one battery terminal to A. Connect (touch) the other battery terminal to Y. Note rotation direction. Leave A connected the same. Now touch other battery terminal cable to YY. If rotation is opposite, it is split series.

If rotation is the same, likely it is a tapped field. See if you can detect a difference in speed between the two connections.

Regards,

major

Thanks Major.
I have just checked and the main drive appears to be between A and Y. I can run between A and YY but it does go much slower PLUS I noticed that the connector for YY is only 6mm unlike the other two being 8mm.

Its strange it will run Y to YY albeit slow and A to YY still slow, but that might just be residual magnetism in the armature I guess in the Y/YY config.
It always runs the same direction.
Also it runs the correct direction for my gearbox (CW looking from the brushes end) so that is good.

I also put 50v on A/Y it and it sure took off, I am thinking when I get things running I will see how it runs using just 125V instead of the 174V I have available.

What are your thoughts generally about the suitability of this motor?

John