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Mechanics and Construction => Mechanics and Construction => Topic started by: df143 on December 28, 2011, 08:29:23 AM

Title: Can anybody help me decide on what efficient and cost-effective actuator to use
Post by: df143 on December 28, 2011, 08:29:23 AM
Can anybody help me decide on what efficient and cost-effective actuator to use for my project? I need to automatically open/close a ball passage.
Title: Re: Can anybody help me decide on what efficient and cost-effective actuator to use
Post by: Soeren on December 28, 2011, 07:47:30 PM
Hi,

Can anybody help me decide on what efficient and cost-effective actuator to use for my project? I need to automatically open/close a ball passage.
Like in your other post, you give absolutely no useable info about what exactly you want to do, so it's hard to give any useable help (these things are closely correlated).
If you tell us what you need to do, we can help - if not, we can't, simple as that ;)

Like...
What do you define as a ball passage?
How large and of what material is the ball?
Is the passage horizontal or vertical?
Feel free to fill in as much metric data as you can - we're not mind readers unfortunately.
Title: Re: Can anybody help me decide on what efficient and cost-effective actuator to use
Post by: df143 on December 29, 2011, 06:54:49 AM
thanks...

I am making a project.
The problem is this:

In a shipping department of a toy company, the balls roll-down a conveyor and through a chute single file into boxes for shipment. Each ball passing through the chute activates the switch that produces an electrical pulse. The capacity of each box is 24 balls. Design a logic circuit to indicate when a box is full so that an empty box can be moved in position.

The size of the ball varies, so we use about a half-an-inch-diameter ball.
Another requirement is that, there is some kind of defect detection. If the ball is defective, it will go to a certain bin otherwise it goes to the box for shipping.

So I am having trouble with an actuator that will hold one ball and check if it's defective or not and then releases it at its proper designation.

I won't be having trouble with the defect detection because I will just use black-colored ball for defective and white-colored ball for non-defective.
Title: Re: Can anybody help me decide on what efficient and cost-effective actuator to use
Post by: df143 on December 29, 2011, 06:59:04 AM
See here's a proposed design of the project.
Title: Re: Can anybody help me decide on what efficient and cost-effective actuator to use
Post by: Soeren on December 29, 2011, 01:55:40 PM
Hi,

Design a logic circuit to indicate when a box is [...]
Do you have to build the physical circuit or is it just a paper design your teacher wants?


So I am having trouble with an actuator that will hold one ball and check if it's defective or not and then releases it at its proper designation.
If you send them down a vertical or slanted tube slighly wider than the largest ball and the smallest ball is larger than around half that width, two solenoids could be used. A blocking pin or a flat piece, spring loaded to block the tube (through the middle of the tube) will stop all balls and a similar second "gate" around a ball diameter lower on the tube will let you release one ball at a time. Each gate pulled open by a solenoid.
The inspection window can be a suitable opening in the side of the tube midway between the gates (as long as it's kept smaller than the balls).

Before releasing gate #2, be sure to close the gate #1 to block the rest of the balls.
If you cut a short piece of the same tubing and  connect to the bottom of the first tube by a piece of suitable diameter hose, a servo could easily move the short piece in a semi circle and position it over (flared) tubes, leading to either the box, the reject bin or where else you want it to go.

Ten your logic just need to produce servo signals of the right width to select where the ball should go - after defects checking, but before release of gate #2.


I won't be having trouble with the defect detection because I will just use black-colored ball for defective and white-colored ball for non-defective.
That may get you in trouble, you little redneck - I bet you hailed for a White Christmas as well ;)
Title: Re: Can anybody help me decide on what efficient and cost-effective actuator to use
Post by: df143 on December 29, 2011, 10:21:03 PM
"Do you have to build the physical circuit or is it just a paper design your teacher wants?"

Yes, I have to build the physical circuit.
Title: Re: Can anybody help me decide on what efficient and cost-effective actuator to use
Post by: df143 on December 30, 2011, 01:57:25 AM
"Do you have to build the physical circuit or is it just a paper design your teacher wants?"



Yes, I have to build the physical circuit.