Switching motor direction using 2 seperate momentary switchs?

[ninja bear]

Hi All
I am a new member and a mechanical designer by trade so forgive my mechanical approach to electronics...
Basically i would like to be able to change the direction of a motor using 2 separate momentary switches instead of a 3 way switch.
The reason for the momentary switch encase your wondering is to move the motor in increments which is my next question: how can i guarantee the increments are the same if the momentary switch is pressed quickly or held for a delay?
I would greatly appreciate any help/direction
Thanks
Kev

 

[user_88]

There are several types of motors that are available. Can you provide more detail regarding your application? Is it possible to estimate the load torque that is required?
Why is the rotational increment important? What increment would be satisfactory ... or unsatisfactory?

 

[crutschow]

A stepper motor controlled by a microprocessor, or perhaps a counter circuit, would allow a precise number of motor steps (and thus rotation increment) to be generated for each switch closure.

 

[carbonzit]

Basically i would like to be able to change the direction of a motor using 2 separate momentary switches instead of a 3 way switch.
The reason for the momentary switch encase your wondering is to move the motor in increments which is my next question: how can i guarantee the increments are the same if the momentary switch is pressed quickly or held for a delay?

Based on what you've written, I have no idea what you really want to happen here.

95% of being able to solve problems here is being able to clearly explain the problem in the first place.

So what exactly do you want to happen when each of the momentary switches is pressed?

• Incrementally change the motor's speed (up/down)?
• Move the motor some fixed number of rotations?
• Stop/start the motor?
• Reverse the motor? (Your title implied this, but your post didn't explain how this would happen.)

If you can clarify this, I'm sure someone can offer helpful suggestions.

 

[ninja bear]

What im trying to achieve is a gear indicator (highlights what gear you are in) NB: these are available for bikes with electronic speedo but mine is cable driven

My thoughts are to fit a micro switch above and below the gear lever which will move the rotary motor when engaged, the motor will have a brush fitted and move over contact pads on each move (which is why i need the increments to be uniform but necessarily a particular distance). A micro switch either side of the motor arm to kill it when at the lower and upper gear limits, each pad will light an LED to represent the gear and the reason i need to operate the motor in both directions with two separate switches is for the micro switches above and below the pedal/gear arm (which im sure you've worked out).
I told a mate today about the idea who is good with electronics (but unfortunately too busy to help) and he laughed at me and said there a fair simpler ways involving programming electronics at which point i went deaf.

Hope this helps you to help me lol
thanks again for your time
Kev

 

[carbonzit]

So you're using a motor to move a bicycle derailleur, is that correct? The motor is driving the arm of the shifter through a lead screw or some other arrangement? And you want it to move a certain distance for each gear change?

It would have been better to have told us that up front.

 

[crutschow]

If you are talking about gear indication on a (motor) bike then, as your friend stated, an electronic approach is the way to go. See this thread for some info on doing that. Your electro-mechanical approach is way too kludgey.

 

[ninja bear]

thanks all and 'crutschow' the link was useful and pretty much what im after but the concepts use programming and electronics which is way over my head

i'll post on that thread and see if they will be kind enough to let me pay them to make me one?

thanks for your time
Kev

 

[randyrivera]

directionwith3 wwaytoggleswitch

 

[Pommie]

directionwith3 wwaytoggleswitch

You win the prize for the worst first post ever.

Note, thread is 2 years old.

Mike.