| Author | Message | ||
     Jim Butler Unregistered guest |
I have had two flap actuators go south on me. In both cases, the actuator just kept extending until the rod was bound against the flap bell-crank, and then stopped. The limit switch seemed to be working in the second case, I can't say for sure in the first case. I am yet to pull the second actuator out of the airplane to take it apart and see if I can tell what went wrong. The incidents were about 8 months apart, with trouble free flap actuation in between. Jim | ||
| Roy Howard Davis New member Username: Royhdavis Post Number: 16 Registered: 01-2003 |
Jim, I will guess that the power transistor that controls the motor current inside the motor housing failed short so that even though the limit switch worked the motor continued to run. Can you trace out the circuit and test the transistor or send it back to us and we'll figure out what went wrong. The redesign I proposed above should eliminate this problem too. | ||
| Jim Butler Unregistered guest |
Roy, I can pull it and send it to you. I'm not experienced at much board level stuff. I would be quite interested in getting something together soon that would prevent this from happening to me again. Thanks for your support. Jim | ||
| paul mikaelsen New member Username: Pmikaelsen Post Number: 6 Registered: 07-2002 |
My 2 cents worth --- The flap motor seems to be a good motor. The circuit board that accompanies it is worthless. My advice is to pull it out and throw it away. Replace it with two external relays and a polyfuse and use some good quality limit switches. Sealed limit switches are available for about $14 each and the rest of the components can be purchased at Radio Shack. if anyone is interested in a circuit and part numbers, just let me know. Paul | ||
| Roy Howard Davis New member Username: Royhdavis Post Number: 17 Registered: 01-2003 |
Ok, here's what I'm thinking it takes.  S1 and S2 are the stick flap control switches with up/down and center off positions. The switches labeled Up and Down are the limit switches. PF1 is a Polyfuse, which will probably be the 9.5 Amp unit for the 12 Volt system. D1 provides some logic to allow both the up and down positions of the stick switches to activate relay K1. K1 provides power to the motor when activated and shorts the motor hot lead to ground to lock the motor when it's off. K2 provides lead reversing in the down direction to run the motor backwards. You want to make sure this is a break-before-make relay to keep from shorting the power to ground. M1 is the flap motor with the electronics stripped out and the two motor leads brought out to this control circuit. The diodes across the relay coils are snubbers to catch the inductive kick of the coil and keep the spikes off the power bus. Anyone see anything I missed? | ||
| paul mikaelsen New member Username: Pmikaelsen Post Number: 7 Registered: 07-2002 |
ROY It looks good you might want to add DPDT switch to the system to switch the ground from Pilot to Copilot if both control sticks are wired up. PAUL | ||
| henri walser New member Username: 43henri Post Number: 8 Registered: 02-2001 |
Hello Express-builder, I get my first kit from Ken Wheeler long time ago without the flaps actuator. Andre Goepfert, a other old Express-builder from Europ and me start to find a flapsactuator. We found the original actuator by a company Linak in Danemark. This actuator was first without some fancy electronic parts for some greenhousewindows and airconditionfalps to open and closed. Later with some demand the make this electronic controlplatine for individuale control closing/opening the windows/flaps, with this new proceture the have to make out 5 wire .... The motor are very strong a Bosch DC motor also you find the same motor in some car-window .To change the wireing, open the actuator ,put out the platine and hockup 2 wire direct to the motor and make the connection like Roy's wiring. Happy builing Henry | ||
| wayne Unregistered guest |
I recommend you install a spring loaded to off flap swt and have limit swts to cut the power at each end of travel. All that fancy stuff causes problems,but sure looks neat. | ||
| Tom R. Hutchison New member Username: Tomhutch Post Number: 142 Registered: 01-2003 |
Where does one place these limit switches? On the bell crank? It seems to me this application begs for a combination position encoder and limit switches that could be placed on the flap torque tube. Tom | ||
| Jerry Sjostrand New member Username: Jerry Post Number: 37 Registered: 08-1999 |
Tom, That (on the torque tubes) is where they are on my Express and 3 others I have seen but they all have the older drive motor without internal switching. Works great using micro switches and reversing relays. |