Hello please, I wish to develop bottle filling application using a rotary table, I dont have a stepper motor, I have just a simple dc motor. Now I know I need to regulate the speed of the motor, now what I need to know is how can I wire this motor so that the shaft can stop with prcision when even the sensor detects a bottle for filling application,

I will appreciate any help
Thanks

 

Well it is not just simple like this to reply to this question!

We dont have layout /configuration of the system...

Is the DC motor used for convoyor belt..
like these notes:

DC motor is type of rotary electrical machines that
convert electrical current into mechanical motion. In this
paper a DC motor is used to rotate the conveyor belt to
move the bottle first under the valve and after it filled move
it away from valve[7]. This DC motor operate 12 DC supply
with gear box which is used to increase the torque and
reduce the speed as required as shown in Fig.(3).

If you can share a mimics screen shot or synoptic of the system , we can try to assist you!

I got a document explaining same system:

So you can use a PLC as described below

The PLC used in this paper is of type LS (XEC-DN32H) of
the relay type and the software program is XG5000 with
XGB-XECH type CPU. The Ladder diagram language is used
to write the program by using computer. Where the program
has been description in four step as shown in Fig.(9):

First step:
Through the first step, push button is switched hence the
motor run and the conveyor belt is moving and carrying the
bottle towards the valve.The normally closed conntact
(valve) is placed to ensure that when valve ON (in step2) the
motor is OFF
The water filling machine in this paper can fill up to 5 or
more bottles in one minute depend on the size of bottle. The
power consumed in this system is low because the PLC need
only 24v dc for operation and the DC motor operate at 12v
while the sensors operate at 5v and also the structure of this
system is simple because the wiring of the input and output
devices is very easy and the control is done in the PLC
through software program. T

I am sure that informations I shared here , can help a lot

Please clarify your schematic/installlation/layout /configuration of the system/plant.

Looking to hear back from you soon,

Controls Guy25.

 

Hello thanks for the reply.

Please I simply want to understand how u can control the dc motor to precision that is all, for example like indexing, if I want the shaft rotate and stop at 45 degrees, how do I achieve that ?

I want to use the dc motor for small rotary table filling application thanks.

 

Hello thanks for the reply.

Please I simply want to understand how u can control the dc motor to precision that is all, for example like indexing, if I want the shaft rotate and stop at 45 degrees, how do I achieve that ?

I want to use the dc motor for small rotary table filling application thanks.

 

That picture show an example of what am trying to develop.

Looking at the dc motor there is a sensor close to the shaft. Once the sensor detects the object place on that shaft the motor stop and the motor shaft follows that precision just like a stepper motor will do.

Please how is that done ?

 

Ephraim...
If it’s a typical non-geared DC motor the simple answer to your question is… No! Especially with your application's dimensions ! There are 2 reasons:
o The 1st reason is related to Parasitic Capacitance. Present in all electrical machinery windings, the effect limits the motor’s ability to operate in small steps like the Stepping motor because input-current build-up is no longer instantaneous, but instead slightly delayed !
o The 2nd is related to coasting. The motor must be braked, electrically, and held in position.

If you want to view a very similar application, search this forum's archive for "Color-Carousel", a fully automatic paint-pigment dispensing machine !
Regards, Phil Corso