Popup lift more than 1m? [Archive]

dzzz

05-15-2009, 01:00 PM

dzzz

05-15-2009, 02:33 PM

The simplest scissor lift has one edge that moves:

http://www.kdllifts.com/parts/images/scissor-lift-parts.jpg

To be fixed at top and bottom requires compound motion:
http://www.industrialequipmentsales.co.uk/images/scissor-lift.jpg

This could be good for photography :)

Lots of choices in using electromechanical pistons instead of hydraulic:

http://www.duffnorton.com/products/linear.aspx

ntsqd

05-15-2009, 03:43 PM

If you move away from linear actuators then your lift distance is only limited by the longest rigid enough for the job lead-screw length. Those could be in the base of a scissor lift, or they could a 4 post lift timed & driven by chain(s).

Some garage door openers are lead-screw designs. Have a look at how those are built.

Metcalf

05-15-2009, 04:33 PM

Prybry

05-15-2009, 08:51 PM

I would check out a pop up camper at a local dealer...
The top on my Pickupper works well enough that it would support a full hard side shell.
I don't have any good pictures of how the mechanism works... but here are a couple showing the top up.

http://www.expeditionportal.com/forum/showthread.php?t=14615&page=3

Prybry

dzzz

05-16-2009, 12:55 AM

Thanks for all the suggestions.
I spent all day on design. When I put the criteria and constraints together I come up a triangular, or one sides pop-up. The back if the camper hinged. The front of the camper lifted to a solid wall.
I like the stability of having a hinged end. I could also use two linear accuators to lift the top, but have a solid end wall carry the load. (The wall could be hinged to the roof, and drop down with just gas dampeners.)
That would give we a 7'x6' second story sleeping area, with a ceiling that went from 3' to six feet. I hate coffin cabovers. One of my criteria was not to sleep with a ceiling a foot above my face.
One note I'll mention from my research today. There are waterproof marine actuators. They use these for hatch closing and underwater trim. I don't have a use yet, but these sound promising. :)

ThomD

05-16-2009, 01:39 AM

Have you seen this?

http://www1.ttcn.ne.jp/~gyo/English/index.htm

http://www1.ttcn.ne.jp/~gyo/open.gif

OutbacKamper

05-16-2009, 03:32 AM

This is something that I spent quite a bit of time thinking about myself;

If I were building a lift top that is hinged on one side (or end) I would go with a very simple and proven gas strut system like this:
http://www.innovan.com.au/video/setup.html

If I were building a horizontal lift system (all four corners lift at the same time) I would use hydraulics (like Alaskan) or a variation of the "tent trailer" style lift system such as:
http://www.goshenstamping.com/content/lift_system.htm
Or a scissor lift system like this topup camper:
http://www.truckaddons.com/Catalog/subpages/topup_campertonneau.htm

Cheers
Mark

vhram

05-16-2009, 02:26 PM

I was going to suggest the hydraulic Alaskan camper type lift with a pin.My Alaskan camper is 35 years old and still works like a champ. Very simple system.

dzzz

05-16-2009, 05:17 PM

Use a lever. Just because you can't find a stroke long enough doesn't mean you just can't move down the arm.

Are you trying to do a triangle hard side pop-up?

If its hard side you can have the inner and outer shell touch each over with some long brush seals. As long as the 3 sides that move have some support and a close fit the only other force you should be seeing is perhaps the entire shell trying to lift off the bottom part. That would put the lifting device in tension...and maybe the weak side of the ram piston.

The brushes are a good idea. What size of space would you put between the walls? I'm thinking about 1/2 inch (~1cm) Would you put brushed within the space between walls, or just at the top of the lower wall? I'm thinking of a six inch overlap.

As far as uplift, that condition is why I wouldn't use gas springs. Although perhaps these devices can be made to stop pushing when fully extended. With a hinged roof I will use something like a 30" linear actuator to open the roof six feet. My only concern with this much leverage is damage from localized force where the actuator arm meets the roof beam.

Metcalf

05-17-2009, 12:31 AM

I planned with the unimog camper I designed ( see my sig line ) to use brush seals on the moving and non-moving edge. That way it is well supported and will be sealed enough to keep dust and breezes to a minimum.

Here was another innovative top idea that I came up with. I think it would work VERY well. It allow almost a doubling of interior space while still maintaining a simple pass through to the cab that stays fixed. It also allows a fixed door on the side of the camper.

http://i125.photobucket.com/albums/p60/Metcalfphoto/newconcept.jpg

http://i125.photobucket.com/albums/p60/Metcalfphoto/topup.jpg

How the camper top works.....small video...hope this works...

http://i125.photobucket.com/albums/p60/Metcalfphoto/th_newconceptcamper.jpg (http://s125.photobucket.com/albums/p60/Metcalfphoto/?action=view&current=newconceptcamper.flv)

dzzz

05-17-2009, 01:06 AM

I've been working on something similiar with a one piece wall that swings down. It's a bit more involved but puts a window at the right height for my design.

In you model, if the roof and upper wall portion is extended I think the weather tightness would improve.

I like the box covering the door if there is internal access.

Positive pressure would be an easy way to keep the dust out. But I expect a deep field of brushed works well, with the air sticking to each brush.

JetMech

06-25-2009, 09:43 PM

I would recommend a ball screw actuator. Reliable and offer very long lifting lengths.

Here's some tech info:

http://duffnorton.com/products/mech2.aspx

63tlf8

06-26-2009, 01:47 AM

I would recommend a ball screw actuator. Reliable and offer very long lifting lengths.

My infrequent posts are normally in the MOG section. Now I'm in the build mode I have made some binding decisions and this is one of them.

I went through this process over the last 12 months and to suit my own requirements, finally went with screw jacks. Ball screws here are far too expensive for the weight and duty cycle so I went with acme threaded rod. I purchased 12 Ft of rod, 4 nuts and eight 2 tonne jack bevel gears. I've made 4 bevel gear boxes from some 70mm RHS and used taper roller bearings as the thrust race. The pinions are actually 3/8 socket extensions so I can easily link the two front and two rear jacks with torque tubes. The jacks are encased in sliding sections of square tube, with the inner tube secured to the nut at one end and the upper mount on the other. My normal lift is 800mm but could be more. One benefit is that I can lift the top section clear of the bottom whilst still on the jacks to service the sliding seals. Makes that maintenance very easy.

The threaded rod solution won't be for everyone but as the lift distance increases it remains in the decreasing list of potential options. Finally, as a positive displacement system, it overcomes the synchro problems of linear actuators or the simple hydraulic, pneumatic systems.

Tony

tlbrewer

06-26-2009, 08:35 AM

My infrequent posts are normally in the MOG section. Now I'm in the build mode I have made some binding decisions and this is one of them.

I went through this process over the last 12 months and to suit my own requirements, finally went with screw jacks. Ball screws here are far too expensive for the weight and duty cycle so I went with acme threaded rod. I purchased 12 Ft of rod, 4 nuts and eight 2 tonne jack bevel gears. I've made 4 bevel gear boxes from some 70mm RHS and used taper roller bearings as the thrust race. The pinions are actually 3/8 socket extensions so I can easily link the two front and two rear jacks with torque tubes. The jacks are encased in sliding sections of square tube, with the inner tube secured to the nut at one end and the upper mount on the other. My normal lift is 800mm but could be more. One benefit is that I can lift the top section clear of the bottom whilst still on the jacks to service the sliding seals. Makes that maintenance very easy.

The threaded rod solution won't be for everyone but as the lift distance increases it remains in the decreasing list of potential options. Finally, as a positive displacement system, it overcomes the synchro problems of linear actuators or the simple hydraulic, pneumatic systems.

Tony

Ok now you've got us all interested in seeing the final product all assembled. HaHa. I've often considered this as a possibility for a lifting mechanism as well. My problem is the only experience I have with them is on aricraft landing gear (C-130's) where they can be very dirty (due to lubrication issues) and require periodic adjustment. A clean, efficient, self contained ball screw assembly with 3-4 feet of travel would be... well let's just say it would solve some design ideas.

Tom

JetMech

06-26-2009, 12:11 PM

Nice home built jack screws. The tapered bearings should provide nice smooth operation. Don't forget to allow access for lubrication of the screw and nut as they can tend to drag or bind when dry. I like the torque tube idea that should be the way to go and a easy fab. If you can source some inexpensive 12/24vdc gear motors to drive your jack pairs a simple limit switch circuit would provide for accurate positioning and easy solo or remote operation. Not really necessary but kind of trick to watch and may be handy when setting up in ugly weather.

ntsqd

06-26-2009, 03:26 PM

If you are going to use a motor I would suggest using one motor and do the synchronizing with some sort of positive drive assembly, like a chain & sprockets or a cog timing belt and pulleys. It can take a lot of controls work to keep motors synchronized. Unsynchronized motors possibly means binding up what ever you're moving. That would be unpleasant in bad weather. All that it would need would be for one side to move more easily than the other.

Something to note about Acme threads; since they are designed to transmit force they are poor at binding up. Meaning that it is almost impossible to do something like use a second nut to "jam" the threads at any particular position. What this means is that there is the potential for vibration (gusting winds, road vibration, etc.) to change the setting. This may or may not be a problem, but I'd suggest designing in a method for securing what ever you're moving that is independent of the threads.

JetMech

06-26-2009, 05:09 PM

Actually he could add a additional bevel gear in two of the gear box's to provide a 90 degree output from those two box's. Tie all four together with three torque tubes and drive them from a single input. Each screw would stay in time as they will be physically tied together and any binding or drag will be shared by all four screws. A simple hand crank with cog style lock would be the cheapest way to raise and lower. Install rubber stops and tabs on the full up and full down positions and run the top until it slightly compresses the rubber then lock the cog this will keep the assembly under tension and eliminate creep. I would probably go with a gear motor or even a pneumatic impact gun with the hammers removed to drive the assy. Another good use for the onboard air and I'm kinda lazy like that.

63tlf8

06-27-2009, 12:19 AM

“lubrication of the screw and nut as they can tend to drag or bind when dry. I like the torque tube idea”

When your Mog has a million grease nipples, another few are no big deal. I have included lubrication for all the components.

“designing in a method for securing what ever you're moving that is independent of the threads”

Will be done using pins through the sliding tubes to locate the roof in the up position. The upper section lowers onto bump stops and I have a few over centre catches in mind to hold it in the down position

“add a additional bevel gear in two of the gear box's to provide a 90 degree output from those two box's. Tie all four together with three torque tubes and drive them from a single input. A simple hand crank with cog style lock would be the cheapest way to raise and lower”

Jury is still out on this. Current plan is for my wife and me to participate in synchronous winding. Halves the load and complexity. Have considered the powered options and decided no electrical method will be used. I have air and air ratchets so that is always an option for the future however a simple fore and aft torque tube will reverse the direction of one of the pinions which would really make your day. Coupling requires a bit of thought to get it reliably right.

Cheers

Tony

63tlf8

06-27-2009, 01:10 AM

Ok now you've got us all interested in seeing the final product all assembled. Tom

Hi Tom,

Too early to see the finished product but here is a .jpg of a very rough sketchup model. Things are progressing!!!

Tony

chnlisle

06-28-2009, 03:51 AM

Or just buy an old Alaskan and flat bed it.

63tlf8

06-28-2009, 05:22 AM

Or just buy an old Alaskan and flat bed it.

If that throw away line were possible I would, just to save a heap of time, but as new or old Alaskans just haven't made the journey here I guess I'll just have to make something a little like one.

Cheers :beer:

Mickldo

06-28-2009, 11:58 AM

Hi Tom,

Too early to see the finished product but here is a .jpg of a very rough sketchup model. Things are progressing!!!

Tony

Looking good so far Tony. Where are you based in Oz?

63tlf8

06-28-2009, 10:33 PM

Looking good so far Tony. Where are you based in Oz?

G'day Mick,

Canberra. Looking Ok. I don't have the resources to prototype so I will have a few experimental techniques in the build and the outcome may be a bit different to some of the industry standard solutions. I'm building in the backyard so the weather isn't ideal at the moment. Still, there's always something else to do and plenty of time to do it in.

You have to look on the bright side, after reading all the canter woes at least I don't need to worry about my chassis.:sunny:

Tony

Mickldo

06-29-2009, 03:53 AM

G'day Mick,

Canberra.

I won't hold that against you ;)

Looking Ok. I don't have the resources to prototype so I will have a few experimental techniques in the build and the outcome may be a bit different to some of the industry standard solutions. I'm building in the backyard so the weather isn't ideal at the moment. Still, there's always something else to do and plenty of time to do it in.

There is heaps of info on here so good luck. If there are any construction technique questions you have just ask, I am foreman at a workshop that does very similar work plus there are a heap of other talented people on this site that can help. PM me if you want.

You have to look on the bright side, after reading all the canter woes at least I don't need to worry about my chassis.:sunny:

Tony

Now that is just cheeky:sombrero:

63tlf8

06-29-2009, 07:18 AM

I won't hold that against you ;)

There is heaps of info on here so good luck. If there are any construction technique questions you have just ask, I am foreman at a workshop that does very similar work plus there are a heap of other talented people on this site that can help. PM me if you want.

Now that is just cheeky:sombrero:

1. You shouldn't. After all it's (collectively) your reps that give the place it's bad name. Just keep them at home and we'll all be happy.

2. Thanks for the offer, not being in the game makes it difficult at times. The site is full of good information. I now have time on my hands, was an engineer (Mecheng) and much earlier a Fitter / Turner and Diesel Fitter so I have enough background to muddle through. Unfortunately no shop so its a backyard job. I would give your left for some of the setups I've had in the past.

3. You pays your money etc... Actually I was looking at a Canter quite some years ago and it would have met my particular requirements if the tyres / rims / difflocks / suspension changes etc hadn't cost more than the MOG. Happy with what I have with all its limitations and you can't turn one into the other.

I was in Brisbane for the first two weeks in June, the time it wasn't raining. I'd be making a sight more progress if I was there now.

Tony

Mickldo

06-29-2009, 09:53 AM

1. You shouldn't. After all it's (collectively) your reps that give the place it's bad name. Just keep them at home and we'll all be happy.

2. Thanks for the offer, not being in the game makes it difficult at times. The site is full of good information. I now have time on my hands, was an engineer (Mecheng) and much earlier a Fitter / Turner and Diesel Fitter so I have enough background to muddle through. Unfortunately no shop so its a backyard job. I would give your left for some of the setups I've had in the past.

3. You pays your money etc... Actually I was looking at a Canter quite some years ago and it would have met my particular requirements if the tyres / rims / difflocks / suspension changes etc hadn't cost more than the MOG. Happy with what I have with all its limitations and you can't turn one into the other.

I was in Brisbane for the first two weeks in June, the time it wasn't raining. I'd be making a sight more progress if I was there now.

Tony

1. No problems. :bike_rider:

2. Yeah it sounds like you have the skills. Lack of workshop has been my main problem in recent history. Luckily I have that covered now, I have just moved into a new house with a huge shed. Of course that now means I have no money for the next 30 years or so......

3. Yeah sometimes you just have to make the best of what you have. I'd love a Mog, OKA, Canter or an Isuzu but I am going to have to make do with my 100 series for a while longer yet.

Did you make it to the Brissy camping show while you were here?

63tlf8

06-29-2009, 11:18 PM

1. Did you make it to the Brissy camping show while you were here?

No, looked at the pix on the forum when I got home. We're up there regularly and last went to the show in 2004 (on a Thu or Fri from memory) Place was absolutely chockers at 10 and you could hardly move.

Fortunately I have everything I need so not in the market for anything new. I'm a little past the point where any brilliant design I saw is able to be incorporated into mine so I did some jobs for my Mum instead.

Mickldo

07-19-2009, 11:11 AM

63tlf8

07-19-2009, 10:48 PM

I am looking at chopping my 105 and making a camper like Soenkes. I have been thinking about all the various lift mechanisms a lot lately. On Saturday morning I was at the recycling shop at the local tip and I saw a couple of Hill's clothes hoists there. That got the wheels turning.
Has anybody (aussies) ever pulled apart a Hill's hoist? Would the internals be any good for use in a pop top lift? Might be a cheap source for lift mechanisms.....

G'day Mick,

Anythings possible but there is a lot against it. My Hills had a cheap rack which means leverage issues, the gear needs to be mounted at the top of the cab to allow the rack to remain within the cab shape when lowered etc etc. I've looked at just about every system that has been used plus a few that are "secret" from Australian campers.

Everything depends on your priorities and preferences. Many of my observations in the decision process have been borne out by comments in this and other forums by people who have that system. Rather than rehash a lot of bandwith on systems that many others wouldn't choose, PM me and I can let you know what I found out on a range of options and you can then use that info in your own selection.

I'm happy with my own selection. Against it for some are that it's manual where many want to just rub the bottle, and it only cost about $400 for the full 4 jacks with a 950mm lift (plus a squillion hours of my free time which certainly isn't an option for many)

Being in the business with access to a workshop would make the choices far more open for you too.

Cheers

Tony

M.Bas

07-31-2009, 11:17 PM

I've been somewhat stumped at how to do a hardsided popup more than a meter or so - lets say 48" - to 52". Straight piston, or double pistons, don't seem to be that long. The issue isn't strength, it's the torques that occur in real word use. I can use compound movements, but all of these I've considered are either weak or complicated. How would you do a large 48" popup? How would you do a 2m one side popup (The other end is just a hinge). How would you deal with the side loads caused by wind?
I did a quick search and found a Dutch supplier (manufacturer is German)

Technical highlights

-stroke up to 9 m
-linear speed up to 17 m/s
-linear thrust to 20,000 N
-positioning accuracy up to 0.08 mm
-no energy consumption at stop
Should be enough to lift a poptop :drool:

They probably aren't cheap since it are heavy duty industrial actuators (which introduces a whole lot of other problems).

So I think the problem is not finding an actuator that extends 1 meter, but finding an actuator that does that using a 12V or 24V DC motor and you are able to mount on you vehicle.

And a 2 meter one side pop up? If the actuator is strong enough it doesn't need to be the full in length.
From the same manufacturer as above, they have a 24V DC actuator that has a 500mm stroke, has a trust of 3000N, speed of 20mm/sec, a 0.1kW motor and weighs 5kg's. 2 of them should be able to lift almost any one sided pop top I guess.

ps. they to customs actuators so maybe they are willing to do a 1 meter stroke with a DC motor (24V) if you ask them.

whatcharterboat

08-01-2009, 12:16 AM

Hey Mick. Found this.
http://www.customcylindersintinc.com/camper_trailer_roof_lift_system.htm

Know you'll find that interesting but I saw something really cool last week. >>> A super cheap and simple airbag system that stitches to pop top soft sides and inflates with a mini compressor. You still need scissors but the airbags do the actual lifting. Only new so I don't think he has a website yet. I'll see if I can get some pics.

michaelgroves

08-01-2009, 11:42 AM

Not much technical information about this, but here are a couple of pics of a Unimog belong to a Belgian couple we met while travelling. IIRC, he had a small electric winch mounted on the cab roof for doing the raising. We really admired the design! Did it all himself, too.

30836

30837

whatcharterboat

08-01-2009, 12:25 PM

Hi Michael, That truck is amazing. And the mog looks OK too. Haha.

Actually the mog reminds me a little of the Innovan system here in Oz. See the Queensland Caravan & Camping Show thread.

I found the website for the Airlifter too >>> rvairlifter.com.au See the pic below.

http://rvairlifters.com.au/rs/10/sites/541/user_uploads/Image/Misc_photos_103__Medium_.jpg

whatcharterboat

08-01-2009, 12:27 PM

Oh Yeah Michael, How does he get the bike up and down from the roof of that mog?

michaelgroves

08-01-2009, 12:51 PM

Oh Yeah Michael, How does he get the bike up and down from the roof of that mog?

I was wondering that myself!

Mickldo

08-03-2009, 09:48 AM

Oh Yeah Michael, How does he get the bike up and down from the roof of that mog?

I was wondering that myself!

Is that a davit crane hanging off the RHF corner of the camper?

At least I hope there is a crane, I'd hate to ride it up there.:Wow1:

michaelgroves

08-04-2009, 09:20 AM

Is that a davit crane hanging off the RHF corner of the camper?

Well spotted!

Bogo

08-25-2009, 03:59 AM

Lifting mechanisms. Popup trailer campers often use a cable and pully system. Not perfect as the cable sometimes comes off the pulleys. That can be solved with captive style pulleys. A bicycle chain and sprockets can be used in place of the cable and pulleys.

The mechanism is usually made out of a sliding c section tube inside a fixed one. The cable is attached to the bottom of the sliding tube and the popup top is attached to the other end. There is a pulley at the top of the fixed tube. Then the cable is pulled on the top lifts. One of these at each corner and you can evenly lift a top.

The neat thing about this design is it is possible to make one that will lift much higher than the length of the fixed tube. It is done with multiple sliding tubes. The meshing of the sliding tubes can be a bit tricky, but it can be done.

When the top is lifted, a u channel is placed over each of the lifts and the top is lowered onto it. This supports it so it doesn't fall if the cable breaks.

The cables are usually gathered and clamped together to provide only one cable to pull at the winch. Some routing may be needed to provide enough length of draw between pulleys for the cable clamp. A simple hand winch, much like those used for trailering a boat, is used for raising and lowering the top.

http://www.customcylindersintinc.com/camper_trailer_roof_lift_system.htm
Has hydraulic systems that replace the cable systems in many popups. Powered by a battery operated drill. Prices for kits are under $800US.

Coleman cable operated. They do the combining of the cables differently than Jayco does.
http://img38.imageshack.us/img38/5304/colemanf.jpg

There appears to be a method I didn't know about. Goshen Stamping Co (http://www.goshenstamping.com/content/lift_system.htm). makes a system where heavy springs are pushed through tubes. Looks neat, I'd be worried about water crossings.
http://img269.imageshack.us/img269/6575/26607201.gif