Quick release mechanism electrically operated?
Quick release mechanism electrically operated?
(OP)
Hi there
I've come here after a heavy unlucky browsing looking for a quick release mechanism. Any hints are most welcomed, honestly I do not know where to look. It's not something complicated, but it has gave me a lot of hard time. I've searched the forum for some ideas, but nothing to fit the profile.
Basically the application involves a linear motor that needs to be coupled to an axle. The axle has at one end an compression spring. After the linear motor and the axle have been coupled, the spring is compressed.
An now it's the problem: I want to release the axle at various spring loads, so I guess a quick release mechanism electrically operated will do the job. But I haven't found any, well almost any...
The beneficiary of this mechanism will be a mobile robot, that will be more than happy to finally be able to walk or better say jump :)
The actual solution involves a quick release mechanism for hydraulic fittings (see the pic, only that it's modified a bit to need less coupling force) , but the release it's possible in just one position (where I put the limit claw that makes the coupling to be separated)
The spring will have maximum load around 40N and the coupling mechanism should be light and at most 20mm diameter.
I've tried to use an electromagnet, but for this holding force is too bulky and heavy. Honestly now I'm working at a solution that will make Frankenstein proud: to actuate the quick release in the pic with a little servo used in hobby RC servo
I find it a little odd to find all kind of solutions coupling circular moment, but very few regarding linear movement. Just point me into the right direction, 'cose for sure these days had made me crazy
Oh, it' just like a man want to buy shoes in mall: only women sandals are there :D
If you know companies that build such devices write a PM is cannot be put on the forum.
Thanks for taking the time reading this!
I've come here after a heavy unlucky browsing looking for a quick release mechanism. Any hints are most welcomed, honestly I do not know where to look. It's not something complicated, but it has gave me a lot of hard time. I've searched the forum for some ideas, but nothing to fit the profile.
Basically the application involves a linear motor that needs to be coupled to an axle. The axle has at one end an compression spring. After the linear motor and the axle have been coupled, the spring is compressed.
An now it's the problem: I want to release the axle at various spring loads, so I guess a quick release mechanism electrically operated will do the job. But I haven't found any, well almost any...
The beneficiary of this mechanism will be a mobile robot, that will be more than happy to finally be able to walk or better say jump :)
The actual solution involves a quick release mechanism for hydraulic fittings (see the pic, only that it's modified a bit to need less coupling force) , but the release it's possible in just one position (where I put the limit claw that makes the coupling to be separated)
The spring will have maximum load around 40N and the coupling mechanism should be light and at most 20mm diameter.
I've tried to use an electromagnet, but for this holding force is too bulky and heavy. Honestly now I'm working at a solution that will make Frankenstein proud: to actuate the quick release in the pic with a little servo used in hobby RC servo
I find it a little odd to find all kind of solutions coupling circular moment, but very few regarding linear movement. Just point me into the right direction, 'cose for sure these days had made me crazy
Oh, it' just like a man want to buy shoes in mall: only women sandals are there :D
If you know companies that build such devices write a PM is cannot be put on the forum.
Thanks for taking the time reading this!
It's nice to be important, but it's more important to be nice!





RE: Quick release mechanism electrically operated?
RE: Quick release mechanism electrically operated?
Thanks for sharing your ideas!
The electromagnet idea is very appealing: it's clean and sexy. But from my calculation... it's not.
Here on the forum maybe I can find some info regarding electromagnets and verify by results. I'll have a try: at least now this idea has one more supporter :)
The robot is kind of spherical one with 12 legs, radially disposed this makes thing more challenging.
I do not understand the leverage mechanism idea. Can you elaborate, please?
I need suggestions, the one neuron I have left is still able to understand something :D
It's nice to be important, but it's more important to be nice!
RE: Quick release mechanism electrically operated?
But, after finding out you will use 12 legs and each leg shall be activated the same way, this idea might be very difficult to implement due to the space requirement for the magnet side and the pivots connected on to the body or each leg by depending on the required locations of spring(s).
Of course the size and the mass of the robot are the major driving factors. I am not sure if you can reduce the mass. Changing materials might be an option if possible.
How are you going to activate the electromagnets in the system? Is the robot going to be electrical and a cable attached all the time? Is it going to have solar power (size might be problem) or batteries( mass and size are be large)? There are a lot of unknown in your project for us. Actually you are the best person to answer them all together and find the optimum solution.
I suggest you to look at the book called "Mechanisms and Mechanical Device Sourcebook" for selecting the suitable idea for your case. It includes the robot mechanisms as far as I remember.
It is too late now. I need to go to bed before I start sleeping in front of the monitor. Good luck.
RE: Quick release mechanism electrically operated?
It's pretty tiny space in the center around the legs there's some space but the mases should be balanced.
I'll double check the electromagnet solution to be on the safe side.
The book you've recommended and another one is already on their way, hope to found something useful.
Have a good night and thanks again for your input!
It's nice to be important, but it's more important to be nice!
RE: Quick release mechanism electrically operated?
If money is no object linear servo motors have a good power to weight ratio. Look up Linmot. or Trilogy. See also voice coil actuators, cheaper than servos but better than electromagnets.
RE: Quick release mechanism electrically operated?
Regards,
RE: Quick release mechanism electrically operated?
RE: Quick release mechanism electrically operated?
Lakey You mean to find a small permanent magnet that can hold a 40N load and when I want to release it to energize the coil wrapped around the magnet? I think I've seen something similar for security doors. I'm not sure if I can block most of the magnetic force with the coil. Do you have some hint for computing this. Your suggestion has one big advantage: electrical current is needed only when detaching. Sweet!
hendersdc I know what you mean. One of the earlier designs was based on your idea. I've abandon the idea because of some technological problems and necessary space vs useful force.
Please share your ideas, as saplanti it's a brainstorm after all, even if I'm grumpy and ...
In any case I appreciate your input, it takes valuable time just to read the thread, what to say about sharing an idea.
It's nice to be important, but it's more important to be nice!
RE: Quick release mechanism electrically operated?
I didn't get it.
There are a host of solutions but I need a picture.
RE: Quick release mechanism electrically operated?
Here is the fast coupling. Is not the exact type but it's close
h
And here's a part of one article where we present the robot:
http://
Look at part 6 (Stop) and 9 (fast coupling). I've used first a fast coupling used in pneumatics, but after 20 cycles is dead. Instead on th the plastic coupling I have a metallic one, much more resistent. But if I change the whole thing, It would be a nice feature to make decoupling any time I like.
It's nice to be important, but it's more important to be nice!
RE: Quick release mechanism electrically operated?
RE: Quick release mechanism electrically operated?
Yes, that's correct.
A Neo. magnet (3/4" Dia. x 3/16" thick) should provide a hold in excess of 90N. A 1000 ampere-turns coil should destabilise the flux sufficiently for the release of the spring mechanism.
The actual size of your magnet and coil will depend upon your application and should be resolved by experiment.
Best regards
RE: Quick release mechanism electrically operated?
There may be a holding electromagnet configuration available but this would require power to hold.
Traditionally pneumatics would be used in a device of this configurations. This would require heavy umbilical of pneumatic tubing.
Take a look at "stock drive products" "Berg Precision" or Automotion. May have some suitable hardware.
RE: Quick release mechanism electrically operated?
Lakey thanks for the aditional info. Can I get your atention again a little bit?
1. From where you've got those values? Can you help me out with some formulas? It tooked me some time to find some useful equation for electromagnet holding force. I know that the problem is not simple, I just want a little more human formulas
2. Let's say I want a maximum holding force of 50N.
2.1 I load the spring with 20N, so I have 30N until I can break the magnetic coupling with excesive load
2.2 I have to destabilise the Neo. magnet. Since the spring is compress 20N, I have to beat 30N with the electromagnet, right? For that I must build an electromagnet big enough to hold 30N and to put it in a way it can reduce the NEO. magnet force? Or the electromagnet can be smaller becouse it acts more directly on the NEO. magnet and not on the holding plate.
2.3 If I'm right I have to use a bigger electromagnet if I want the load to be relesead at smaller spring compression rates. That's correct?
alansimpson I'm going to look at those products. The thing is that I have the linear motors already and I must deal with that
A pneumatic cylinder will do the job, but will raise other problems regarding stroke control. All around me at work love pneumatics and hydraulics and I'm the one floating against the current using electric devices. I need to show them I'm right
All the best!
It's nice to be important, but it's more important to be nice!
RE: Quick release mechanism electrically operated?
2. I'd guesstimate that an ½" Dia X ¼" NdFeB magnet would do the job. You can adjust the maximum hold by means of an artificial air-gap, such as a stainless steel or brass shim.
Once you're satisfied with the 'hold' you can begin the tweak the needs of the coil. As mentioned, the coil only requires enough power to disrupt the magnet – anymore is a waste.
2.2 I suggest that you make a bobbin and then wind the wire onto that, so this assembly will slide comfortably over your magnet. I wouldn't confuse this device with an electromagnet – I suppose the device in question is the opposite of an electromagnet, but we don't want to be drawn into a discussion about terminology!
2.3 It depends - all things are relative! You will probably have to balance your design around the power of the available magnet. Note the grade of the magnet because if it's overheated it may become useless.
You need to conduct your tests to find the best balance.
Good luck & regards,
RE: Quick release mechanism electrically operated?
RE: Quick release mechanism electrically operated?
2.In that new thread, please provide the required additional information to solve the problem.
-handleman, CSWP (The new, easy test)
RE: Quick release mechanism electrically operated?
The tripping toggle rests against a stop just a degree or so past center. A force that is extremely small in relation to the force of the main spring will move the toggle past top dead center and allow it to collapse and release the stored energy of the main spring to open the breaker points.
Look for an old breaker to play with. Take the cover off and use a rod to move the common trip bar.
DON'T PUT YOUR FINGERS INSIDE THE MECHANISM. USE A TOOL OR ROD TO TRIP THE BREAKER.
THE STORED ENERGY IN EVEN A SMALL BREAKER CAN DO SERIOUS DAMAGE TO A FINGER. A LARGE BREAKER IS CAPABLE OF REMOVING PART OF A FINGER.
Examine a few old breakers to get a feel for the action and then work on adapting the basic principles to your project.
You will find a very, very large ratio between the stored energy force and the tripping force. I understand that this is what you are looking for.
Bill
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"Why not the best?"
Jimmy Carter
RE: Quick release mechanism electrically operated?
You'd love the stored energy actuators on the big SF6 breakers.
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If we learn from our mistakes I'm getting a great education!
RE: Quick release mechanism electrically operated?
I've uploaded one patent I've found regarding what you've said. It looks like the one you are talking about? I'm from Romania so for sure the designs could vary for those circuit breakers.
The design looks similar to this?
h
All the best!
It's nice to be important, but it's more important to be nice!