Need help -- Non contact motion sensing of product.

[antsrealm]

Hi,

I have a small air conveyor that moves bottle lids down into a filling machine. I want to be able to detect a jam up in the conveyor at a certain point regardless of what type of cap or how tightly packed the caps are. It also has to be non-contact. We were looking at distance measuring lasers but it wasn't a great solution.

I was hoping there was some kind of motion sensor similar to the one that turns on your flood light but smaller that could detect if there was motion on the line eg. bottle caps moving. And then if it stopped or ran empty the motion would stop and the signal goes low indicating a problem with the caps.

Is there anything like this out there ?

Thanks,
Tony.

 

[osmanmom]

any picture or video can post ?

 

[antsrealm]

any picture or video can post ?

Not at the moment, i'm on days off at the moment and having a think about it. I can get one next week. It's pretty basic though, just plastic bottle lids flying down a guided air conveyor at 37,000 / hr. Just need to detect motion preferably without a vision system. Just something that detects movement like a standard motion sensor just maybe more sensitive.

Thanks,
Tony.

 

[osmanmom]

check this link,

www.tesensors.com/us/node/412

www.blwvisser.nl/image/pdf_products/Technicalsolutionsoverview.pdf

www.blwvisser.nl/image/pdf_products/hydepark.pdf



www.ia.omron.com/products/family/501/download/catalog.html

www.ia.omron.com/data_pdf/cat/e4b_d065-e1-01.pdf?id=501

call salesman for more info.

 

[dploof23]

Are the lids round? Do they lie flat next to each other? Assuming you have a PLC in play here and this is the case you could use a laser sensor from Keyence and create two timers in the plc. One is driven by the sensor being on, and the other by the sensor being off. If either timer times out, movement has stopped.

Dave

PS Look at the LRZ series laser sensors from Keyence, I built a cap counting machine that accurately counts caps to the tune of 50,000+/hr. using the LR-ZB240CB. The caps shoot past the laser packed tightly together but the fact that they are round allows the sensor to see the difference in distance from the leading/trailing edge of the cap to the center.

 

[antsrealm]

Are the lids round? Do they lie flat next to each other? Assuming you have a PLC in play here and this is the case you could use a laser sensor from Keyence and create two timers in the plc. One is driven by the sensor being on, and the other by the sensor being off. If either timer times out, movement has stopped.

Dave

PS Look at the LRZ series laser sensors from Keyence, I built a cap counting machine that accurately counts caps to the tune of 50,000+/hr. using the LR-ZB240CB. The caps shoot past the laser packed tightly together but the fact that they are round allows the sensor to see the difference in distance from the leading/trailing edge of the cap to the center.

Yeah we are using a baumer laser to do exactly this however the diameter of the caps change with different products and the trigger range for the laser needs to be re-trained. This may still end being the way we go but I was hoping there might of been a better way.

 

[antsrealm]

I am considering using a distance measuring laser on 4-20ma and comparing the distance, if it hasn't changed in a certain time it must be jammed. Do you think the laser and the 4-20ma card would read the changes in distance quick enough to see the different distances in the caps diameter as it moves along at 37,000 /hr?

 

[Mill_Control]

Since it's an "air conveyor" will problems cause a detectable pressure, or flow, change?

 

[danatomega]

If the Baumer laser works well, why not employ several of them and select which one is active based on what product you are running?

 

[shooter]

Mount a very simple lighteye , just above the last cap , if no cap is in place, (if you put it in an angle there always be a cap in front of the eye )stop machine, this you also can do some caps in front, as long as it is not jamming below.

 

[TConnolly]

In air conveyors the load on the blower motor is directly proportional to the mass being moved. Conveyor clogs are detectable by a change in load on the motor. Load sensors similar to these from www.loadcontrols.com may be able to do what you want and seem like magic to everyone else but you.

http://www.loadcontrols.com

 

[Badger]

37,000 P/H equates to just over 10 per second, thats fast. If the powerflow sensor works so could a Hall effect sensor wired to an analogue input, try putting an ammeter on the motor cables and measure the difference between the two states, blocked and unblocked.If it is significant the Hall sensor would be pennies, compared to anything else.

 

[Badger]

Another thought, put a simple windmill above the conveyor and sense it is turning with an inductive sensor. When the conveyor blocks the windmill should stop.

 

[Mill_Control]

In air conveyors the load on the blower motor is directly proportional to the mass being moved. Conveyor clogs are detectable by a change in load on the motor. Load sensors similar to these from www.loadcontrols.com may be able to do what you want and seem like magic to everyone else but you.

http://www.loadcontrols.com

If the motor is already on a drive that has an analog load/current output automation direct sell a signal conditioner with relay outputs. Part # 884116. I'm using the window function on them to only allow the infeed to run when the motor is running and not excessively loaded. Even if the motor is currently ATL a drive plus signal conditioner might be easier, and cheaper, to implement.