4-Way Acoustically Transparent Masking - Page 5

You can buy the SpringAssist here: http://www.av-outlet.com/en-us/dept_511.html
At the bottom of the page. Cheap too!

Now that I think about it more. That little gizmo would be great since it'll fit right into the 1.5" diameter aluminum tubes AV-Outlet sells too! Hmmmm.....

Yes that's the sort of thing I was thinking of.

Also, have a look at this pdf here: http://www.silentgliss.com.au/doc/do...50AB142A87AE84

There's quite a few different blind systems there that might be suitable, especially the Tess 100 system.

Edit: In fact, the Tess 120 looks perfect, as it incorporates side guides which would mean it could be directly used in the orientation needed for side masking: http://www.windowworldhi.com/Specifi...120%20data.pdf
Can't seem to find any prices anywhere though!
Ben

Boy, wouldn't that system be sweet. Almst plug & Play.
Betcha they use Somfy motors... and you know what that mean$.

Ran across this company, GoelstAmerica, someone may have mentioned them in regards to skylight shades. Maybe this would work for those who would want to use curtains as masks. Below is a pdf link for their 6200 series 24V motorized drapery rod, their lit says it has a variable speed motor, soft launching / docking & up to 5 presets programable. Of course there is no pricing on their web site Their US office is near Atlanata. Take a look:

http://goelstamerica.com/fileadmin/p.../6200%20UK.pdf

John

OMG that's perfect! Exactly what I"m looking for! I'm one of the few who will be using a variable image size, 4 way masking (and not merely CIH) so those pre-sets are a god-send.

I only hope it isn't going to be as expensive as it looks

Anyway, I've contacted the company and they only do quotes via email, so I'll
be sending an email to check them out.

Thanks very much!

Please let us know what you find out.

TIA!
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Axel

When I was a kid, I used to use magnetic "Reed Switches" in my projects as limit switches. You use a magnet on the moving part and the reed switch can be mounted on an adjustment plate. Magnetic alarm switches, used on doors and windows are a good example of this type of system.

What if you mounted a magnet or magnets on your cable with heat shrink tubing, far enough away from the pulleys not to interfere with them. And you mount the limit switches on sliding adjustment plates, allowing you to set your stops or limits.

Below, is a radio shack link to the type of switch available at a low cost. You can take the magnet out of the plastic case and heat shrink it to the cable assembly and use the reed switch housing as-is. The switch housing already has screw holes for mounting.

http://www.radioshack.com/product/in...entPage=family

Actually, you can use the normally closed contacts of the switch and when the magnet activates the reed relay, power is cut. You then re-apply power when needed, which overrides or bypasses the limit switch.

Control of your motor assembly can all be accomplished with simple relays which cut voltage continuity to the motor, stopping its rotation at your preset limits. Everything can be either linked to your projector's trigger outputs or controlled with Xantech IR activated relays.

I know this concept is not a very elegant solution, but sometimes inexpensive and simple implementation is the best means to an end.

Hey folks. If I wanted to use the above product, with the 5 presets used for
variable side masking widths, would you suggest I go for the IR or the RF remote control option?

Ideally I would like my RTI T3 universal remote (which can do both IR and RF, and works with a universal RP6 controller) to have pre-programmed image width selections.

Thanks.

Hi Audiodynamics,

Thanks for the info, simple is always a good plan. I have
a couple of questions;

Does it take special wiring to start the motor once again, after it has been shut off by the first reed swt ?

Will each reed switch position require a seperate relay to break the current flow for each new AR stop ?

Would someone sketch this out and display it for us ?

Do you think proxmity switches would work in the same way as a reed swt ?
-------------------------------------------

Rharkenss, do let us know what they tell you. They sent me a pdf of the instruction maual. I can email that, if somone wants it, just PM me.

John

Well the quote for the GoelstAmerica 6200 motorized drapery system was actually pretty good, comparatively and all things considered.

The quotes I was getting for a 160" BTX BTX Drapery System 5060 were closer to $2,000. Whereas the quotes for the same size Goelst system is several hundred dollars less, and then after the discount for my company (you might have to have a company, or be an installer to purchase) it's lowered another $440 more!

Given the Goelst system does even more than the BTX system, especially those luscious
5 pre-sets and apparent ease of installation, I may have found my masking/curtain system!

Cheers,

Contgrats Rich!
Concerning RF vs. IR. I found that in most cases RF communication protocols, unlike IR, can not be learned by universal remote controls. So in short, I would definitely verify that RF is in fact an option for you, in case you went that route.
____
Axel

Awesome, Rich! I contacted Goelst too. The main company won't quote or sell to individuals. I asked for info on just the motor kit, 6200-00 Motor Set and the 6220 Drive Belt.

Their reply:

"I'm sorry, but I cannot quote directly to an individual. If you will let me know where you are located, I'll refer you to a dealer. However, we normally, do not sell components to end users, only assembled products."

I'm still waiting for the dealer info.

Rich, can you get a quote on the motor set and drive belt?

Andy

A guy a while back, Bob Trinanes, was working on that very thing. Here is the archived thread --> http://archive2.avsforum.com/avs-vb/...hreadid=350149

Hey! Archive2 is back!

Anyway, I think he had some schematic on the relay setup he used. Check it out.

Andy

"Does it take special wiring to start the motor once again, after it has been shut off by the first reed swt ?"

No special wiring is required. This entire control system can be built without the aid of any solid state circuitry.


"Will each reed switch position require a seperate relay to break the current flow for each new AR stop ?"

NO and YES. It depends on the current draw of the motor. If the motor draws more current than the reed switch contacts are capable of handling, then the reed switch contacts will burn out. In that case, a second relay will be necessary for current handling capability. In the worst case, two relays will be required to control one masking motor. Three position masking systems (Retracted, 4:3 and 16:9) will require three reed limit switches and may require three relays, again depending on the motor's current draw.


Do you think proxmity switches would work in the same way as a reed swt ?

There are several thypes of proximity switches. Ex: photoelectric, inductive, ultrasonic, binary, etc. The magnetic reed switch is a proximity switch in a simple form.


Here's an overview of my proposed control system:

A relay is a simple electro-mechanical switch. Applying voltage to the relay coil moves the relay contacts. The relay contacts act as a switch passing voltage from an external power supply to the masking motor, turning the motor on or off and reversing the motor's direction.

This system can be IR controlled with a Xantech IR activated relay or can simply be connected to the projector trigger. Using the PJ's trigger is simplicity in itself.


The projector trigger can be used to activate the coil of a Double Pole Double Throw relay (DPDT). In many cases, the PJ trigger may not have enough current to activate a relay coil. In this case, a solid state circuit can be used to activate the relay coil. Even easier, a special relay called a sensitive relay is designed for this purpose.

Caution: DO NOT attempt to use the PJ's trigger output to power the motor.


A. When the PJ's trigger is active, the relay can apply power to the masking motor.

B. When the masking has extended to a preset point where the magnetic reed limit switch is activated, the limit switch opens the circuit stopping the motor.

C. When the PJ's trigger is then deactivated, the contacts of the DPDT relay in it's off state can provide power to overide the limit switch, re-starting the motor and in turn moving the masking system back to it's retracted position. A second limit switch will prevent the masking from retracting too far.

D. Basically, two limit switches are required per masking panel. One limit switch sets the fully extended position and the second limit switch sets the fully retracted position. Three position masking systems (2.35 AR when retracted, 4:3 and 16:9) will require three reed limit switches (a limit switch for each position) and may require three relays, again depending on the motor's current draw.

E. Utilizing a DC motor in automating this DIY masking system will simplify things greatly. With a DC motor, the same DPDT relay which is activated by the PJ's trigger, if wired correctly, can reverse voltage polarity to the masking motor. This will reverse the motor's direction, returning the masking system to it's fully retracted position.

This concept is actually very simple to assemble, wire and implement. It should also be very reliable.

I'm happy to assist the first guinea pig who wishes to implement this proposed control system.

EDIT: The number of programmable trigger outputs your PJ or Video Scalar offers will determine whether or not you can control a three position masking system (2.35 AR when retracted, 4:3 and 16:9). You'll need two trigger outputs for three positions. If you only want a two position masking system (16:9 / 4:3) then one trigger will suffice. If you don't have enough trigger outputs, then the Xantech IR Relay block will provide complete control.

Good Find Andy!

I just read through Bob's DIY electric masking thread. Fantastic Design! Bob's control system is very similar to what I've proposed. I'm often amazed at the level of creativity and skill exhibited by a lot of you folks here at AVS!

I solve my client's issues by designing custom solutions for high end applications. My hats off to all you guys who tackle the tough jobs yourself and to those who have at least tried. And to the OP Scott, congratulations on the design of your great DIY masking system. The simplicity makes it that much more attractive.

My suggested automation control is a low cost, simple alternative that works seamlessly with the PJ's or video scalar's 12 vdc triggers. And it should easily be retrofittable to the OP's DIY masking system.

Got an odd question, was wondering if automobile timing tape could be used for an optical encoder to read the revolutions of a screen motor when wrapped around a spool or pulley ?

http://www.speedwaymotors.com/pl/243...ing-Tapes.html

Did you look at the "Marvomatic" post mentioned earlier, where the fellow had a home made striped tape wrapped around the roller of his Stewart screen, being read by an optical device ?

Is there some relationship in spacing or thickness of the black & white lines so that a reader can see it properly ?
Does it need to match in some way to the what the motor control board might be looking for as steps or pulses ?

Just wondering?

John

Hi Audiodynamics,

I did not see a "IR relay block" on Xantech's web site, did find a #CC12 a "remote relay module". Is the relay block called something else & do you have a part number ?

I am very interested in your approach, simple is great. I am in the planning stage, no projector or screen as yet.

I plan to use a DC motor for horiz & verticle masking on a
4' x 8' screen and to have 2.35, 1.78, 1,85 & 4:3 AR's and maual adjustment (tweeking). What type of DC motor would work best with your limit switch / relay design; a gearmotor or stepper (bipolar, unipolar) ?

Is there an RPM target recommended for the motors, is 24 RPM too slow or 80 too fast ?

Don from HTIQ recommended a torque rating of 150oz-ins (thats a tough motor to find).

In your experience, how close do the magnets need to be to the reed switches to trip them ?

John

Hey all,

In case you're having trouble seeing Bob Trinanes' old relay wiring schematics here they are. I think I"m going to go his route and use his original wiring diagram (#1). Very simple.

Andy

 

electricmaskwiring.pdf 41.4599609375k . file

 

electricmaskwiringrevised.pdf 48.177734375k . file

 

electricmaskwiringrevised2.pdf 42.7578125k . file

The Xantech CC62 Remote Relay Module (Relay Block) is the unit most suited because it has Six DPDT Relays built in.

We are a Stewart dealer. Since time is money, we prefer to sell an in the box solution for the Screen and Masking. Frequently, our clients often have unusual automation requests, requiring us to create "out of the box" solutions. The reed proximity switches and Xantech CC62 Relay Block are two of items I usually keep in my parts bins.

A DC gear motor is most suitable for your project. As for the RPM and torque requirements, it really depends on your masking design and the size of the pulleys you utilize. Larger pulleys will require less torque. Grainger sells a variety of gear motors. Since I do not build masking systems, HTIQ can provide a better answer than I.

Reed switches can be purchased from most alarm suppliers and are available in many styles. Some operate when the magnet is within an inch, while others will activate with the magnet farther away. It depends on the magnet provided. Depending upon the proximity of your cable assembly from the reed switch mounting plate, you can always experiment with the size of the permanent magnet.

Remember, my suggestion is to attach the magnets to the cable assemblies via heat shrink tubing. The reed switches are attached to semi-permanent but adjustable sliding mounting plates, allowing you to adjust the limits of your masking system. When the magnet on the cable travels to the limit switch, the motor stops, whether that position is fully retracted or anywhere along the way.

If you get the mechanicals of your masking system built and working reliably, I will be happy to assist you with its automation and control system. You'll need to figure out if 2 motors or 4 motors are required to motorize your masking panels. Also, if your PJ or VP has multiple trigger outputs for multiple AR's you don't need the Xantech. If you wish to operate your DIY masking via IR, the Xantech is a must. Depending upon your configuration, I will draw up an appropriate schematic wiring diagram for you.

Alternate Limit Switch Option:

http://www.alliedelec.com/Search/Pro...79D1B00DE4E17F

The Hinged Roller Lever Switches can be actuated by large (1 inch) wood or metal Beads (Round ball with a hole through the middle) that are hot glued onto the cable assembly.

Thanks Audiodynamics,

Great info & thanks for the help! Folks around are sure wonderfully helpful. I have really enjoyed this thread, a real learning experience. I am still wowed by OP Scott's wonderful design !

John

My first design used a magnet and a number of reed switches to set positions. One thing to watch out for is that if the reed switch operates for example 1 inch away from the magnet, the system will stop at a different position depending on the direction of travel. I.e. if the masking is closing it will stop 1 inch short of the magnet, and if opening the same but the opposite side of the magnet. This means you have 2 inches of difference for the same position!
In practice the distance was not as bad as an inch, but there was always a small amount of difference in position.

Ben

Ditto

I use the reed switches as limits in a variety of automation projects, typically with linear actuators. They are precise enough for the job.

The Roller Lever Switches I suggested will be more precise than most magnetic reed switches. If really critical adjustment is required, the Roller Lever Switch will allow for more precise and consistent limits.

As far as the reed switches are concerned, it's all dependant on the switch assembly. Before purchasing all of the reed switches for the job, experimentation with a variety of switches is a good idea. It's important to find a switch that only activates in very close proximity.

The round or button type, flush mount reed switch that alarm installers use on doors and windows typically require very close (1/2 - 3/4 inch) proximity to open the switch contacts. And they are really cheap in bulk. These switches are mounted by drilling a hole in the top of the door for inserting the magnet. Another hole is drilled directly above the magnet in the door jamb and the reed switch is inserted. For this application, the problem with the recessed reed switch is mounting it! I suppose the button switch can be mounted in a piece of 3/4 inch plywood with slots for adjusting switch position. With flexible adjustment for both position and distance from the magnet, I believe the button type reed switch can allow accuracy within 1/4 inch tolerance. Since there will be a little image overscan onto the black borders of the screen, a limit switch with 1/4-3/4 inch tolerance is more than acceptable for this application.

http://www.alarmcontacts.com/product...048a2d98f599f2

I think I'm inclined to go with the roller switches Audiodynamics spoke about. They would eliminate any chance for any inaccuracy and are easier to install. I'm not sure if we need ones rated at 20A though

There isn't really any high current going through the switches so lower rated (and less expensive) ones can be used. Thanks for the link Audiodynamics!

Andy

It won't hurt to use the 20 amp switches!

Andy,

Thanks for the link.
Would we need one spring assist in each roller tube? Say I am wanting to do a 4-way masking with four 1.5" EMT pipes from HD or Lowes, would I need 4 Rollease spring assists ? Or just one per set (horiz & vert pairs) to keep tension on the pair, since I guess we'll have a figure "8" shaped cable run between the rollers to have them roll in opposite directions.
I noticed there is a Left & a Right version, it did not say if there was a difference of rotation direction or was it merely a choice as to which side of the widow shade roller tube you wanted to stuck it into ?
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Audiodynamics, The round/button reed switches that are listed at the link you gave look great:
http://www.alarmcontacts.com/product...048a2d98f599f2

I did not see any mention of their power requirements, do you know what Vdc, mA they would need to be powered ?

John

Reed switches are low current. With a reed switch, a properly rated relay will actually switch the gear motor on/off/reverse.


I'm assuming you'll use 4 motors for 4 way maskingi?

[quote=Andy238;12908151]Awesome, Rich! I contacted Goelst too. The main company won't quote or sell to individuals. I asked for info on just the motor kit, 6200-00 Motor Set and the 6220 Drive Belt.

Their reply:

"I'm sorry, but I cannot quote directly to an individual. If you will let me know where you are located, I'll refer you to a dealer. However, we normally, do not sell components to end users, only assembled products."

I'm still waiting for the dealer info.

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This thread has gone quiet for a few days, don't let it die guys !

Andy,
Were you able to get pricing on the motor assembly & belt drive? I guess you were going to buy a standard curtain rod & alter it to permit the Goelst motor assembly & drive belt to operate it ? How are things going ?

Hi guys,

Ran across this simple curtain rod motor kit on eBay AU, see what you think. Seems aimed to fit standard cord draw curtain rods for less than $100 USD. The link is shown below. Maybe one of our Aussie friends has some experience with this kit as to noise level and & how well it works.

http://cgi.*********/ws/eBayISAPI.dl...0%3D%26fvi%3D1