Page 11 of 21 FirstFirst ... 234567891011121314151617181920 ... LastLast
Results 101 to 110 of 203

Thread: reversable motor for monitor?

  1. #101
    Maximum Bitrate more mods's Avatar
    Join Date
    May 2003
    Location
    Atlanta, Ga.
    Posts
    873
    Quote Originally Posted by MikeH
    Just a couple of minor resistor values and additions...

    I'm afraid I 'm going to have to let others contribute from here. Sorry.
    ok, is this design complete?
    It's the cake having/eating thing.

  2. #102
    FLAC
    Join Date
    Nov 2003
    Location
    Marietta, GA
    Posts
    1,134
    It's about as complete as it could be without putting it together and trying it. I've revised the motor drive a bit in this diagram.
    Attached Images Attached Images  
    MikeH

  3. #103
    Raw Wave
    Join Date
    Jun 2003
    Posts
    1,823
    MikeH,

    I think there maybe a problem with the "door" input. The door switch normally ground the courtesy light when the door is opened.

    All that needed is that the "door" input is pulled high and not pulled low...hope that make sense?

    EDIT :

    But then maybe not because the light will be pulling the "door" input high all the time. My mistake I was thinking theres no courtesy light connected in the circuit...sorry, wasnt thinking

  4. #104
    FLAC
    Join Date
    Nov 2003
    Location
    Marietta, GA
    Posts
    1,134
    Hmmm.. I'm not quite following you. The circuit shown here allows the "door" input to go to +12V on the high end, and be pulled to ground on the low end. I'm assuming that the dome light puts +12V on this lead with the door switch is open (light is off) and the door switch pulls it to ground. Are you suggesting that we pull this input high when the door is open? If so, the PIC has "weak pullup resistors" on each input, which could accomplish this.

    Edit:
    Ricky...you must be sipping the merlot also!
    MikeH

  5. #105
    Raw Wave
    Join Date
    Jun 2003
    Posts
    1,823
    I think you missed my EDITED post above. I think your design is all fine...pressed the submit button to quickly

    How about replacing the transistors with H-Bridge IC to simplify the design? abit expensive though.


    Ricky...you must be sipping the merlot also!

    Lol no...I got some nasty headaches after being in a friends car for 4 hours with some nasty smelling airfreshener...its some rose I think

  6. #106
    FLAC
    Join Date
    Nov 2003
    Location
    Marietta, GA
    Posts
    1,134
    Sorry...I responded to quickly too.

    The H-bridge looks great! I've never used one. Take a look.H-bridge
    Some of them look like a bit of overkill (PWM speed control, etc), but they are nice all-in-one solutions. This is an area where I definitely need others to chime in. C'mon robo-guys (and girls)
    MikeH

  7. #107
    Raw Wave
    Join Date
    Jun 2003
    Posts
    1,823
    This one is dual :

    http://www.maplin.co.uk/products/mod...&moduleno=2837

    This one have protection diodes on board :

    http://www.maplin.co.uk/products/mod...&moduleno=2834

    I have used both of them and they work just great with big motors. Have also used them to drive a home made hi-co magnetic head. The PIC can take care of the PWM drive into the motor...but not really needed I guess. How about slowing down the motor as it get near the limit switch?

  8. #108
    Maximum Bitrate more mods's Avatar
    Join Date
    May 2003
    Location
    Atlanta, Ga.
    Posts
    873
    Quote Originally Posted by Ricky327
    This one is dual :

    http://www.maplin.co.uk/products/mod...&moduleno=2837

    This one have protection diodes on board :

    http://www.maplin.co.uk/products/mod...&moduleno=2834

    I have used both of them and they work just great with big motors. Have also used them to drive a home made hi-co magnetic head. The PIC can take care of the PWM drive into the motor...but not really needed I guess. How about slowing down the motor as it get near the limit switch?
    My motor is tiny! Here are the specs.

    Miniature Metal Gear Motor - 62 RPM

    This small 1.14" (29mm) by 0.47" (12mm) by 0.39" (10mm) motor features a high quality, all-metal 196.6:1 gear train for smooth, quiet operation and a long operating life even under harsh conditions.

    The motor delivers 62 RPM with 46 in-oz torque (3300 cm-gm) while drawing an efficent 120ma at 5v DC. It weighs 0.29 oz (8.2 gram). It has a 3mm diameter "D" shaped output shaft. The shaft can be mated with most 1/8" hole output devices including 1.25" Rubber Wheels. The faceplate contains two mounting holes threaded for M1.7 machine screws such as M1.7 x 4mm Machine Screw. Mfr. # NA4S
    I may need to slow it down a little, I'll just have to test to find out.
    It's the cake having/eating thing.

  9. #109
    Raw Wave
    Join Date
    Jun 2003
    Posts
    1,823
    From the link MikeH posted :

    WARNING:
    Direct motor driving with this chip is only possible for motors that draw less than 100 mA (4427) to 150 mA (4424) under load


    I guess you can use the chip used on that site.

    You can slow down the motor by using the PWM without loosing much torque. But dont make it complicated now if its gonna be your first PIC project as you can always add that code later on.

  10. #110
    Maximum Bitrate more mods's Avatar
    Join Date
    May 2003
    Location
    Atlanta, Ga.
    Posts
    873
    Quote Originally Posted by Ricky327
    From the link MikeH posted :

    WARNING:
    Direct motor driving with this chip is only possible for motors that draw less than 100 mA (4427) to 150 mA (4424) under load


    I guess you can use the chip used on that site.

    You can slow down the motor by using the PWM without loosing much torque. But dont make it complicated now if its gonna be your first PIC project as you can always add that code later on.
    So, what do you think about Mike's design? I dont see anything wrong with it, but I have very little knowledge about electronics.
    It's the cake having/eating thing.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •