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Assembly and Operating Instructions for HiViz.com Kits

 

Crossed-Beam Sensor Frame Assembly (CBS-F)

 

Assembly instructions for other kits

 

This is a new version of the frame assembly for the Crossed-Beam Sensor.The previous version is here.

The new version has these improvements over the previous one:

  • The IR LEDs and detectors are housed in screw-type mounts.
  • The wires are channeled inside the PVC frame rather than running around the outside.
  • The area enclosed by the frame is 40% larger.
  • A handle makes mounting easier.

 

Parts

The parts provided with the frame kit are listed below and shown in the photograph to the right (click to enlarge). All of the PVC parts are 1/2-in inner diameter. Note that the IR LEDs and detectors and the 3.5mm plug are provided with the Crossed-Beam Sensor Controller Kit.

  • 4 12-in sections of PVC pipe with holes predrilled
  • 1 4-inch section of PVC pipe
  • 3 PVC elbows
  • 1 PVC tee
  • 1 PVC end cap with hole drilled
  • 4 screw-type LED holders
  • 2 detector shields
  • Hook up wire (not pictured) with these lengths: black-4.3 ft, green-3 ft, red-1.7 ft, blue-1.3 ft
Tools

Having the right tools will make the job easier. You'll need to provide your own. Here's what we recommend.

  1. 15-30 W soldering iron and solder
  2. Wire stripper (photo below)

  3. A small diagonal cutter (photo below) makes it easy to trim stray wires, but other kinds of snipping tools such as scissors may work.

  4. Needle-nose pliers (photo below) make it easier to handle wires, especially if you have big fingers.

  5. A magnifying glass is useful to inspect solder joints.

  6. Small screwdriver or pocket knife

  7. Hot glue gun
Wire strippers diagonal cutter needle-nose pliers
Wire stripper Diagonal cutter Needle-nose pliers

 

Be sure to solder in a well-ventilated area. Keep the tip of your soldering iron clean by wiping it against a wet sponge. Once the tip is clean, touch a bit of solder to the tip to tin it and improve heat conductivity. Inspect your solder joints to see if the solder flowed well to make good electrical contact. If it looks like the solder formed a bead, that's likely a bad joint and will not conduct. Reheat to flow the solder.

 

Click on any image to enlarge.

 

Assembly Instructions  

Reference photo

 

The various pieces of PVC will fit together as shown in the reference photo to the left. Note that the larger of the two holes in the center of each section of pipe is on the outer side of the square. In the instructions below, we will refer to the various parts using the letters and numbers shown in the photo. As you assemble the pieces below, the photos will show the pieces in the same orientation as in the reference photo.

 
Painting isn't necessary, but if you wish to paint the frame, now is the time. Assemble it as shown in the reference photo and paint with the desired color. We recommend earth colors. When the frame is dry, disassemble it. As you follow the instructions below, you'll assemble the frame piece by piece.

Step 1

 

Remove the nuts and washers from the LED holders as shown to the left. Then insert the infrared LEDs (indicated by LED in photo to the left) and infrared phototransistors (PT) into the holders. Slip the translucent caps over the legs and then push the assembly into the body of the holder. Do this for both LEDs and both PTs. The completed assemblies are shown in the photo to the right.

Step 2

 

You'll be working with side S1 first. Orient it as shown in the photo. Slip one of the PTs in its holder into the pipe from below with the legs sticking out the top, the longer leg to the right. Slip the plastic nut down over the legs.

 

 

 

Step 3

 

The photo to the left shows the view looking down into the larger hole. Using a small screwdriver, pocketknife, or similar tool, work the nut onto the threads and turn it by degrees to tighten it. Complete the tightening with a pair of needle-nose pliers as shown to the right. It's only necessary to tighten until the fit is snug.

 

 

Step 4

 

Assemble the other PT in its holder onto side S3. Assemble the two LEDs in their holders onto sides S2 and S4.The photo to the left shows the PTs and LEDs in the correct positions. (Don't assemble the frame at this point. The photo is just for reference purposes.)

 

Step 5

 

In this step, you'll work with side S1. Cut off one 16-in length of green and two 16-in lengths of black wire. Strip each wire back on one end by 1/2 inch. Wrap each of the stripped ends around a brad or small nail to create a spiral shape as shown in the photo. This will allow the wires to be slipped down easily over the legs of the PT. (Use this same technique later for the other PT and the two LEDs.)

 
As you make wire connections below, it may help to refer to this diagram.

Step 6

 

Orient S1 with the longer leg of the PT to the right. Slip a black wire into the pipe, spiral end first, from the right side. Do similarly for both a green and black wire from the left. Bring these up through the large hole in the center of the pipe. See the photo to the left.

 

The photo to the right shows a close up of the connections to the legs of the PT. Slip the spiral ends of both of the black wires onto the longer leg of the PT and the spiral end of the green wire onto the shorter leg.

Step 7

 

It's now time to start soldering. You'll solder the connections to the legs of the PT, but first slip the wire connections down further into the pipe so that they won't stick out. See the photo to the left for the soldered connections.This completes the connections for the first PT.

 

 

 

Step 8

 

Thread two elbows onto the wires and seat them on the ends of S1 as shown in the photo to the left. Don't seat tightly at this point. You'll do that after final alignment near the end of the assembly.

 

Strip the black wire extending out the right side back 1/2 inch. Do the same with the unused blue wire. Then spiral each of the stripped ends as you did in Step 5.

 

Slip side S2 onto the black wire with the longer leg of the LED toward the bottom. Then slip the blue wire up through the other end of S2. Pull both wires up through the large hole in S2. See the photo to the right.

Step 9

 

The photo to the left shows a close up of the connections of the legs of the LED to the black and blue wires. Slip the black wire over the shorter leg of the LED and the blue wire over the longer leg. Then solder both connections.

 

Step 10

 

Orient side S3 with the longer leg of the PT pointing towards the top. Then slip S3 onto the black and green wires that extend from the elbow E1. See the photo to the left. Bring the wires out through the large hole in S3, and strip and spiral the ends. Slip the black wire over the longer leg of the PT and the green wire over the shorter end as shown in the photo to the right. Do not solder yet. There are two more wires to add in the next step.

Step 11

 

Strip the unused lengths of black and green wires back by 1/2 inch on one end and spiral the stripped ends. Slip these wires, stripped end first, into the lower end of S3 as shown in the photo on the left. Then slip the black wire over the longer leg of the PT and the green wire over the shorter leg as shown in the photo on the right. This will give you 2 black wires on the longer leg and 2 green wires on the shorter leg. You may solder these connections now.

Step 12

 

Thread the tee T1 onto the black and green wires as shown in the photo to the left. Then thread the red wire through the side of T1 and out the bottom. You will now have black, red, and green wires extending out the bottom. In a later step, you'll connect the 3.5mm plug to these wires. For now, just leave them as is.

 

Add the fourth side, S4, now and thread the red and blue wires through the large hole as shown in the photo on the right.

Step 13

 

Strip and spiral the blue and red wires extending from the hole on S4. Then connect the blue wire to the shorter leg of the LED and the red wire to the longer leg. The photo to the left shows a close up with the legs soldered.

 

Step 14

 

Thread the 4-in section, H1, onto the red, black, and green wires extending from the bottom of the tee. Then thread the end cap, C1, onto the wires as shown in the photo to the left.

 

Step 15

 

Cut the red, black, and green wires extending from the end cap to the same length. Then strip each wire back by 1/4 inch.

 

Unscrew the black jacket from the 3.5mm plug and slip the jacket over the wires. Then connect the wires to the lugs of the plug as shown in the photo to the left. Refer to the inset to clarify connections. The black wire connects to the hole on the shaft (1), the green wire to the longer of the side lugs (2), and the red wire to the shorter of the side lugs. Another view is shown in the photo to the right.

Step 16

 

Solder the three connections as shown in the photo to the left. Then crimp the metal tabs as shown to the right.

Step 17

 

Screw the jacket onto the plug as shown to the left. This completes the wiring of the frame.

 

Step 18

 

Twist the sides of the frame as needed to align the LEDs with the PTs. Then press all parts of the frame firmly together.

 

One thing is left to complete the assembly. That is to hot glue the detector shields to the two PTs. Slip the wider end of a shield over a PT and hot glue around the base. Before the glue dries, make sure that the shield is aimed at the corresponding LED on the opposite side of the frame. See the result to the right.

 

Check the connections to the legs of each of the LEDs and PTs to make sure they're separated and not creating a short circuit. If you wish, you may tape over the holes to provide protection for the legs while the frame is in use. (Another option is to squirt hot glue into the holes to stabilize the components.)

 

The completed assembly is shown at the top of the page.

 

If you've assembled the control box, then you're ready for testing. Go to the operating instructions. If not, go to the control box assembly page.

 

 

 


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