Multi-purpose Aluminum Headlamp Design

I am working on a design concept for a headlamp. By recycling some elements from my other designs, this is what it looks like thus far.



Key elements:
a. Infinitely variable output to 180+ lumens with a CREE R2, 0-100% by rotating the knob.
b. Adjustable from spot (about 6 degrees) to flood (about 100 degrees) by rotating the head - shown in flood position. Spot mode will move the head forward by about 9mm.
c. External power source from 4.5V to 10V - can be anything from 3x alkaline to 6V SLA and Lithium Ion. I like the idea of using 7.4V camcorder batteries as they are available in wide variety of sizes/capacities (typically from 1400mAH to 6000+mAH) and quality chargers are widely available.
d. Head can be tilted +/- 35 degrees.
e. Diameter of the head is 25mm. (0.98in) and length to the rear of the bracket is 63mm. (2.48in).
f. Estimated weight (excluding headband) - less than 50gm. (1.76oz).

Any comments/suggestions appreciated.

Re: Design concept - Aluminum headlamp

I would also consider a Q3-5A for a warm tint option.

Re: Design concept - Aluminum headlamp

Emitter options will be considered. Are there any headlamps currently available that have variable/multi output capability AND focusing (adjustable beam angle) optics?
Minor design update:

Re: Design concept - Aluminum headlamp

Will it be possible to attach the light to the battery pack and use it as a lantern too? Would def be interested either way

Re: Design concept - Aluminum headlamp

That is an excellent idea - having the ability to use the headlamp as a lantern. I have incorporated a threaded (1/4-20) hole in the bottom of the bracket that will allow it to be mounted on a standard tripod. An optional base can also be offered for lantern use.

Re: Design concept - Aluminum headlamp

rmteo said:

Key elements:
e. Diameter of the head is 25mm. (0.98in) and length to the rear of the bracket is 63mm. (2.48in).

Any comments/suggestions appreciated.

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Nice project :thumbsup:

Sorry for the question but wouldn't there be the problem with the lamp bouncing? It seems to be long, thin and with weight not exclusively in the rear part...

Re: Design concept - Aluminum headlamp

If it were mounted directly to a helmet the length would not be a problem.

Re: Design concept - Aluminum headlamp

Yucca Patrol said:

If it were mounted directly to a helmet the length would not be a problem.

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Yup, but I thought it's designed to be used as a regular headlamp. rmteo even mentioned the headband in the first post.

Re: Design concept - Aluminum headlamp

Any way to make it shorter? It may feel odd having such a long light on the head. Nice concept...

Re: Design concept - Aluminum headlamp

Thanks for your comments, guys. I have made a revision to the design to make it slightly shorter. Also, this change makes it easier to manufacture, and therefore less costly to produce.



The U-shaped bracket has a threaded 1/2-20 hole that will allow the light to be attached in the following manner:

a. used with camera tripods.
b. direct attachment to a helmet - needs just a 0.25in. hole and a SHCS for secure attachment.
c. and adapter plate for securing to a headband.
d. to a base plate (as in my previous post) for use a lantern.

The light is smaller than it appears in the CAD renditions. It measures 60.5mm (2.38in.) from the front to the back of the bracket - that's only about 10mm. longer than an AA cell.

Re: Design concept - Aluminum headlamp

I like this rendition a lot better than the first one. I have a couple of suggestions though - keep in mind that this is a light that I would use exclusively on a caving helmet:

- Is the red button the switch? If so, accidentally bumping the light into something might cause the light to swivel back and the switch to contact the helmet. It'd be annoying if my light went off every time I bumped my head on a rock.

- For helmet mounting, it would be preferable to have multiple mounting holes (instead of just one). With one hole, there is the chance that the light could pivot on the bolt.

- The wider you can make the beam, the better! I like to be able to see the cave floor AND the ceiling without having to move my light up and down.

Re: Design concept - Aluminum headlamp

The red button is actually the brightness control knob - it will adjust continuously from 0-100% (0 to about 180 lumens). In the earlier renditions, the knob is on the top. In the last iteration, it is moved to the rear (and made much larger for easy manipulation) so it is less like to get bumped.

There is no switch on the light. The battery pack will have to provide the switch - or alternatively, the light can be turned off/on by plugging or unplugging it from the pack without using a switch. The cable exits from the bottom of the body through the "U" in the bracket. I can provide a smaller secondary threaded hole that can be used as an anti-rotation mechanism when helmet mounted.

The wide setting of the beam will probably be about 100 degrees (with spot at about 6-8 degrees). Compare this to a maximum of about 120 degrees for the "flood only" lights such as ZL.

Re: Design concept - Aluminum headlamp

rmteo said:

The red button is actually the brightness control knob - it will adjust continuously from 0-100%

(...)

There is no switch on the light. The battery pack will have to provide the switch - or alternatively, the light can be turned off/on by plugging or unplugging it from the pack without using a switch.

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Why don't you want to use the potentiometer as a switch (e.g a push/push pot)?

Re: Design concept - Aluminum headlamp

On pots with built-in switches, the switch is not able to handle higher current up to 2A. The pot is connected to the MCU and is used to control brightness. When the knob is turned down all the way, current draw is <1mA and should not be a problem in use.

If you are aware of a pot (less than 16mm. diameter, 12mm. long) with a built-in switch that can handle 2A+, please let me know.

Re: Design concept - Aluminum headlamp

rmteo said:

On pots with built-in switches, the switch is not able to handle higher current up to 2A. The pot is connected to the MCU and is used to control brightness. When the knob is turned down all the way, current draw is <1mA and should not be a problem in use.

If you are aware of a pot (less than 16mm. diameter, 12mm. long) with a built-in switch that can handle 2A+, please let me know.

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I'd think that 2A is a problem for a pot but not for a switch. A quick google search shown a few 17mm long ones (e.g. from Lorlin, a Chinese one, few Indian ones, etc.) so 12mm should also be available somewhere...

Re: Design concept - Aluminum headlamp

Those are good finds, thank you, but they are too big. The body of the light is 22mm. with an ID of 17mm. The switch needs to be able to handle up to 2A - the pot is for signal only and its power handling capacity can be anything from 100mW on up.

If you do come across anything else, let me know. I prefer ones where the body is round and the terminations are on the end instead of the side.

Re: Design concept - Aluminum headlamp

Like the new design def count me in. Any ides for the battery pack and wiring?

Re: Design concept - Aluminum headlamp

rmteo said:

Those are good finds, thank you, but they are too big. The body of the light is 22mm. with an ID of 17mm. The switch needs to be able to handle up to 2A - the pot is for signal only and its power handling capacity can be anything from 100mW on up.

If you do come across anything else, let me know. I prefer ones where the body is round and the terminations are on the end instead of the side.

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Well, chances that I will accidentally bump into something that perfectly fits your requirements are rather small. Especially since there are many additional factors - linear or log, resistance, tolerance, dents, price, availability, etc. I have shown those links only to illustrate my impression that if 10A push/push pots with 17mm length are so easy to find then it's possible that you may be able to find one that fits your design.

Re: Design concept - Aluminum headlamp

My requirements for the pot are:

a. linear taper.
b. value can be anything from 10K -100K Ohms.
c. tolerance +/- 10% or better.
d. price, important for a production item - see below.
e. availability - same criteria as d.

I have found several pots (albeit without switch) that will work. The only downside is price - they are typically in the $4-$8 range in quantity - about the same as a CREE XR-E R2, way too high for a production light.

I am inclined to go back to my original concept (which I have not mentioned previusly) of using multi-mode (high-mid-low) instead of continuously variable output.

Re: Design concept - Aluminum headlamp

rmteo said:

I am inclined to go back to my original concept (which I have not mentioned previusly) of using multi-mode (high-mid-low) instead of continuously variable output.[/IMG]

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Nothing wrong with that... multi-mode has the advantage of giving the user a better idea of the remaining runtime on a set of batteries.