JuKu
20-11-2012, 04:17 PM
Hi,
This is my first foray to CNC world. Hi all! I'm an electronics designer and tinkerer. Recently I acquired SMD reflow capability to my lab. After some test runs, I built my first real board. It had 450 components on it, which I manually placed. No way I want to do that again! This, and because it will be a fun project, I'm also going to try a pick and place machine. My goals:
- The machine is targeted to a prototype lab, only a few or maybe just one board at a time. So, no real need for feeders at this point.
- Accuracy and speed must be significantly better than hand placement, but not more.
- Can place loose components. In fact, if the machine asks the user "put R13 (22k) on pickup spot", user does so and the machine then looks at the pickup spot and can pick up the part and put it where it really belongs, I'll be very happy! There would be very little setup needed for my one-offs.
- I'm limited in my machining capability and even more with tools. So, the more I can use off-the-shelf parts, the better.
I'm comfortable with software and electronics, but as noted, a real NOOB in machine building and CNC. Therefore, I would appreciate any feedback and improvement ideas. So, may I present for you to ridicule: JuKu's first CNC desing, the pick and place contraption. The attachment is a picture about what I have so far, the PDF is the same in zoomable and rotateable form. Btw, the PDF is much clearer by selecting solid outline viewing mode.
Starting from right, we have a belt-driven block on a 13mm steel bar that holds a stepper motor. On the same plate (2mm steel, drawn semi-transparent for clarity) there are holders for two other steel bars and a shaft (darker gray), that transfers driving force to the other side. Not shown is the same arrangement on the other end of the bars (sans the stepper, pulley and idler wheel). Sliding along the two bars is another (semi-transparent) steel plate. On top, there is a piece of aluminum profile and a stepper motor with a threaded shaft. (I said I'm limited in machining capability, I'm trying to avoid a need for bending or welding steel.) The threaded shaft motor rises and lowers the pick and place head, which goes between the yellow plates. The whole thing is mounted on two pieces of aluminum profile, oriented 90' to the first bar; the supports are mounted on top of the profile. The tube-like thing with an antenna-looking cable mockup is the camera.
Not shown in this proof-of-concept sketch:
- Bolts don't have washers or nuts. Some bolts are of wrong length.
- The mirror image of the other side carriage
- The pieces of the aluminum profile the whole thing is mounted on
- Belt anchors and tensioners
- electronics, cables, vacuum tubing and solenoid valve
- The actual pick and place head mechanism. I have not designed that yet, but I'm going for this Basic idea: Pick ‘n Place Head « Outguessing the machine (http://tim.cexx.org/?p=728), but improved: There will be a spring load, the motor should be mounted the other way around and I already have the camera.
So, what do you think? Where this contraption sucks the most? (Apart from the suction pipe, not shown.) What I like about this is that is is fun to design. So far, the parts are not very expensive, and most are available off-the-shelf. The custom parts are plates only, with no precision placed holes. In other words, even though I'm buying some laser cutting time for the prototype plates, I can make replacement from aluminum in my own workshop, should I need to.
Cheers,
JuKu
This is my first foray to CNC world. Hi all! I'm an electronics designer and tinkerer. Recently I acquired SMD reflow capability to my lab. After some test runs, I built my first real board. It had 450 components on it, which I manually placed. No way I want to do that again! This, and because it will be a fun project, I'm also going to try a pick and place machine. My goals:
- The machine is targeted to a prototype lab, only a few or maybe just one board at a time. So, no real need for feeders at this point.
- Accuracy and speed must be significantly better than hand placement, but not more.
- Can place loose components. In fact, if the machine asks the user "put R13 (22k) on pickup spot", user does so and the machine then looks at the pickup spot and can pick up the part and put it where it really belongs, I'll be very happy! There would be very little setup needed for my one-offs.
- I'm limited in my machining capability and even more with tools. So, the more I can use off-the-shelf parts, the better.
I'm comfortable with software and electronics, but as noted, a real NOOB in machine building and CNC. Therefore, I would appreciate any feedback and improvement ideas. So, may I present for you to ridicule: JuKu's first CNC desing, the pick and place contraption. The attachment is a picture about what I have so far, the PDF is the same in zoomable and rotateable form. Btw, the PDF is much clearer by selecting solid outline viewing mode.
Starting from right, we have a belt-driven block on a 13mm steel bar that holds a stepper motor. On the same plate (2mm steel, drawn semi-transparent for clarity) there are holders for two other steel bars and a shaft (darker gray), that transfers driving force to the other side. Not shown is the same arrangement on the other end of the bars (sans the stepper, pulley and idler wheel). Sliding along the two bars is another (semi-transparent) steel plate. On top, there is a piece of aluminum profile and a stepper motor with a threaded shaft. (I said I'm limited in machining capability, I'm trying to avoid a need for bending or welding steel.) The threaded shaft motor rises and lowers the pick and place head, which goes between the yellow plates. The whole thing is mounted on two pieces of aluminum profile, oriented 90' to the first bar; the supports are mounted on top of the profile. The tube-like thing with an antenna-looking cable mockup is the camera.
Not shown in this proof-of-concept sketch:
- Bolts don't have washers or nuts. Some bolts are of wrong length.
- The mirror image of the other side carriage
- The pieces of the aluminum profile the whole thing is mounted on
- Belt anchors and tensioners
- electronics, cables, vacuum tubing and solenoid valve
- The actual pick and place head mechanism. I have not designed that yet, but I'm going for this Basic idea: Pick ‘n Place Head « Outguessing the machine (http://tim.cexx.org/?p=728), but improved: There will be a spring load, the motor should be mounted the other way around and I already have the camera.
So, what do you think? Where this contraption sucks the most? (Apart from the suction pipe, not shown.) What I like about this is that is is fun to design. So far, the parts are not very expensive, and most are available off-the-shelf. The custom parts are plates only, with no precision placed holes. In other words, even though I'm buying some laser cutting time for the prototype plates, I can make replacement from aluminum in my own workshop, should I need to.
Cheers,
JuKu