Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations waross on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Tube Hopper Design issue, asking for a solution.

Status
Not open for further replies.

Langless28

Mechanical
Dec 29, 2014
14
Good morning everyone! I am designing an automation project in which I load tubes onto a core for an injection molding machine. I have designed a hopper for the tubes (roughly 3/8" OD, 33" long hollow PVC). Unfortunately I had a feeling the design would result in this but the only way I would know for sure is if I actually built the darn thing! I attached a picture for reference. The tubes are getting held up at the throat, either by friction of the tubes against the left wall or slight twisting in the tubes causing them to fall down the center path crooked causing a jam. Once the tubes are in the center slot area, they transfer as intended on a sled. FYI center slot is 1/2" wide, with the tube OD being 3/8".

Can anyone recommend a fix for this "jamming". I was thinking along the lines of a massager, or vibration to assist but wanted to reach out to any experts on the hopper/feed design world which I clearly could use some help.

Order of desired fixes:
1. Rigid, a plate or diverted can fix it.
2. Pneumatic element massager/prodder fingers.
3. Some other form of movement- gear motor etc.

*EDIT* picture needs to be rotated so the black plate is horizontal and on the bottom of the image.
 
 http://files.engineering.com/getfile.aspx?folder=c21f2092-5979-4f3c-ab92-ff8ae9f557ef&file=IMG_4488.JPG
Replies continue below

Recommended for you

I have done some work with hopper feeding pre-cut and straight steel wires. Our hoppers use a roller at the choke point, where your sheet metal is bent. These rollers actuate (45-90deg.) each time we feed a part, we actually tie the air cylinder to the escapement. The gap is still there but, this acts as an agitator to move the parts if they have jammed. Our rollers for 1/4" dia. wire is around 3" dia. for reference.

For smaller wires we have used a similar cylinder at the choke point that fully cuts off the opening and has a slot for a single part to come through, basically making it an escapement.

The rule I follow for escapements is that if it can happen, it will. You can always jam a choke point, so instead of trying to make it not jam I try to release the jam.
That being said, if you find a way to make a static hopper never jam, please let me know.
 
Long rods tend to easily jam slots because the rods can become slightly crossed so one rod enters the slot first at one end while another rod enters the slot first at the other. You need a roller or belt the length of the slot that will carry jammed rods up out of the slot back up the ramp while new rods feed in over the rods being carried back to try again later.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor