Home |
Search |
Today's Posts |
#1
|
|||
|
|||
24Hr/7 Day timer
I have a project that requires turning a plastic disc (about the same size
as a CD) through 360 degrees in 7 days or 24 hours using a battery powered system of some sort. The smaller and cheaper the better! Can anyone suggest the best way I should approach this problem? Thanks Bob |
#2
|
|||
|
|||
24Hr/7 Day timer
On Wed, 16 Nov 2005 12:21:55 +0000 (UTC), "Bob"
wrote: I have a project that requires turning a plastic disc (about the same size as a CD) through 360 degrees in 7 days or 24 hours using a battery powered system of some sort. The smaller and cheaper the better! Can anyone suggest the best way I should approach this problem? --- Something like a 4060 with a couple of switchable crystals on the front end eventually driving a stepping motor would do it, but what kind of resolution are you looking for at the disc? 1°? 0.5? -- John Fields Professional Circuit Designer |
#3
|
|||
|
|||
24Hr/7 Day timer
"Bob" wrote I have a project that requires turning a plastic disc (about the same size as a CD) through 360 degrees in 7 days or 24 hours using a battery powered system of some sort. The smaller and cheaper the better! Can anyone suggest the best way I should approach this problem? If you don't need much torque, an old 5 1/4" floppy stepper motor would give you 1.8 degree steps (200/revolution). You would need some kind of logic to sequence the motor power wires. The nice thing about using a stepper motor is that even with the power off, the motor will want to hold its position. |
#4
Posted to alt.electronics
|
|||
|
|||
24Hr/7 Day timer
The disk must be very slow moving so a stepper motor would have to be put
through a gearbox I guess (perhaps as high as 250:1). Is there any circuit diagram on the internet that you could recommend for this application? Bob "John Fields" wrote in message ... On Wed, 16 Nov 2005 12:21:55 +0000 (UTC), "Bob" wrote: I have a project that requires turning a plastic disc (about the same size as a CD) through 360 degrees in 7 days or 24 hours using a battery powered system of some sort. The smaller and cheaper the better! Can anyone suggest the best way I should approach this problem? --- Something like a 4060 with a couple of switchable crystals on the front end eventually driving a stepping motor would do it, but what kind of resolution are you looking for at the disc? 1°? 0.5? -- John Fields Professional Circuit Designer |
#5
Posted to alt.electronics
|
|||
|
|||
24Hr/7 Day timer
On Wed, 16 Nov 2005 21:18:20 +0000 (UTC), "Bob"
wrote: The disk must be very slow moving so a stepper motor would have to be put through a gearbox I guess (perhaps as high as 250:1). Is there any circuit diagram on the internet that you could recommend for this application? --- I can show you exactly how to do it, but you have to decide on what you want. For example, if you can tolerate a resolution of one degree, then for a seven day period the motor would step once for every 360th of seven days, or once every 28 minutes. For the same resolution over a 24 hour period the motor would have to step once every four minutes. If you wanted a resolution greater than that then you'd need a stepper which could step in 0.5°, 0.25°,... increments or you'd have to get a gearbox. But whatever you want to do you need to decide what the smallest increment of rotation of the wheel needs to be. -- John Fields Professional Circuit Designer |
#6
Posted to alt.electronics
|
|||
|
|||
24Hr/7 Day timer
On Wed, 16 Nov 2005 21:18:20 +0000 (UTC), "Bob"
wrote: The disk must be very slow moving so a stepper motor would have to be put through a gearbox I guess (perhaps as high as 250:1). Not if it makes a single step every 2-3 minutes, and is a high res stepper. -- ----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
#7
Posted to alt.electronics
|
|||
|
|||
24Hr/7 Day timer
Thanks for all the help. Another news group has suggested I use a clock
mechanism and gearbox. This sounds simple so I think I will try this first. Bob "Bob" wrote in message ... I have a project that requires turning a plastic disc (about the same size as a CD) through 360 degrees in 7 days or 24 hours using a battery powered system of some sort. The smaller and cheaper the better! Can anyone suggest the best way I should approach this problem? Thanks Bob |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Dimplex electric timer ... | UK diy | |||
Washing Machine timer repair | Home Repair | |||
towel radiator and timer switches - again. | UK diy | |||
Intermatic timer question | Home Repair | |||
CH timer workaround - is it safe? | UK diy |