Re: hi help me out guys


<suchi_84@xxxxxxxxx> wrote in message
news:1142338606.546597.167990@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
can the rack pinion arrangement of a dvd player do the trick without
any additional component..ie will that satisfy my need to convert
angular movement of 0.014 degree to linear motion of 1 micron or maybe
even 10 micron.or should i have any other movement attached to
it...reply as soon as possible please

You may well be able to do it using a DVD mech, depending on the mechanical
configuration of your stepper motor. There are two types of mechanism
configuration. The first uses a conventional motor with a diameter of about
2.5cm and a shaft diameter of, I would guess, about 1.5mm. A nylon gear of
about 12 or 13 teeth is a push fit on that shaft. This gear then drives a
larger gear, with a smaller one concentrically moulded with it. This gear
may or may not be made from two parts, spring loaded against one another, to
take out backlash. The smaller part of the gear then drives a similarly made
gear, which then drives the rack, which is attached to the laser sled, which
typically runs on a pair of precision rails, but may be one precision rail,
and one edge of the pressed steel deck, with a nylon face over it.

The other type of drive uses a smaller motor, either conventionally mounted,
and driving a worm gear via a normal gear, and then via another gear,
driving a coarse or fine pitched worm screw, which then drives the sled via
a friction pawl, or mounted horizontally, and driving the worm screw via a
couple of conventional gears. I think that this setup would probably give
the best precision, but the other type would be easier to interface your
stepper motor to.

As I said, if you have a repair shop you could go to, pop in and ask. They
will probably have a box full of scrap decks that you can look through to
see if anything is appropriate to your needs. The only reason that we all
keep them, is for the occasional motor or gear that we can cull from them to
complete an urgent repair.

Arfa


.

Relevant Pages

  • Re: Boeings Electric Taxi Motor
    ... >>>the gear leg itself and then tee it to both wheels really drives up the ... >> What makes you think the motor will be installed within the fuselage? ... However, this usually requires a larger, more expensive inverter, ...
    (rec.aviation.piloting)
  • Re: Sturmy Archer 8 speed
    ... >> and then found the hub slipping in third. ... >> make sure it stayed in that gear, and sure enough it would spin as ... > Let's rule out any worn bits such as the clutch and pins (pedaling ... generate a skew between "clutch" and the pins that it drives. ...
    (rec.bicycles.tech)
  • Re: BMW Auto box gear select problem (offset drive gear???) Wierd
    ... My daughter drives a '00 325i with an automatic transmission. ... I used it recently and noticed that if the car is in N, I had to depress the brake pedal to select D again, but if the car was in R, I could move the shift selector to D without doing anything else. ... This seems to be a safety interlock item that prevents unintended gear changes in an unattended vehicle that might have a child inside. ... I'm about to buy a 3 series BMW (318i SE Auto). ...
    (alt.autos.bmw)
  • Re: Cloudburst
    ... The real problem was that the clutch inner hub's ... shaft has nothing to drive, it just spins uselessly inside the clutch ... splines on the direct-driven fifth gear transmission shaft ... It drives an absolutely stock gear on the other shaft and makes ...
    (rec.motorcycles)
  • Re: Shaft Drive Questions
    ... FINAL DRIVEN BEVEL You can see the spline that drives the ... It's on the left side of the bevel gear. ... HUB DRIVEN The male spline on the final driven gear mates ... In case you're not familiar with cookies, a cookie is a small piece of data that the browser is given by the server and re-presents on every HTTP request. ...
    (rec.motorcycles)