right click on the leader and click edit attachment, click the arrow head then click on an other hole. this should do your trick. if not, just manually add a leaderd which u can place where u want.
so say the max lever arm is as i said it was 3.65m and the mass is 4000kg, then the torque on pin is 4000 x 9.81 x 3.65 Nm.
is this the max torque i need to provide using the cylinder to rotate the conveyor? i should add 20-30% for friction plus margin for error i guess?
the main pin going thorugh the turn table, this is the pin that linkage will be operating on. i.e Pin B in the linkage we have been looking at is the the pin that the turntable and conveyor rotate around.if you can imagine the boom/conveyor rotating +-90deg about the Z axis.
i am nw having...
this is really only a provisional drawing. just illustrating the idea. the chain would just take the load of the conveyor when it is in its working position rather than letting the rams hold the load.
Could you maybe explain what you mean further by it creating uplift?
Potteryshard, do you...
i calculated the forces using the geometry hydtools as advised by rb1957. i made sure i fully understood the mechanics again before just simply applying the equations.
i have attached a pdf of the proposed idea. i will be accelerating at a slow rate, im not sure exactly what. it wont be 1mm/sec...
"what is the torque created on the links from the actual load your trying to move?"
Desertfox, so we now have determined how to find out the forces in the links AD and cd, there fore multiplying the AD link foce by the perpindicular distance to the link B will give us the torque at various...
when the linkage is closed and the ram is now pushing out, i calculate that AD is nw in compression at 80KN and CD is in compression at 36KN.
interested to see what others get.
looking at rb1957 equations for point D, they seem logical and correct to me. working them out for when our cylinder is at full stroke of 1400mm:
approximately, there is a force of 26KN in AD in tension and a force of 58KN in CD in compression.
as a few have said i would have to carry out this...
Thank you desertfox. I have now attached a PDF showing the linkage fully open and also fully closed. I have added as many dimensions as i think you might need to give it a bash. if you need any more let me know...
the turn table will in fact be attached to the pin at B through a keyed arrangement to transmit the torque. it is on this turntable that the 4000kg conveyor will be mounted.
I dont know if you have seen the DWG file i attached desertfox. i will attach a better PDF tomorrow with more...
Nice artcicle ted... just shows, linkages are a whole science in their own respect. smart minds initially thought of such stuff.
So now that we have more or less sorted the problem of calculating the force in the link AD, therefore multiplied by the perpindicular distnce to the pin AB gives us...
bradley rather than using the linkage above to curl a bucket, i am turning it on its flat in order to rotate a mass of 4000kg using the main pin B. is there not a simple method or calculation to determine what torque is needed to rotate a certain mass about a point? is it not an inertial...
guys, i will be back at work on monday and post a pdf as requested FAO desert fox.
all help appreciated thus far. great forum where minds can be brought together to solve engineering problems.
occupant, ive reattached as an earlier cad version (2004). you should now be able to open ithttp://files.engineering.com/getfile.aspx?folder=11072e64-177f-4b5a-a037-71bea39f25fb&file=Linkage_Drawing_version_2006.dwg
desert fox, the straight link is actually in reality a curved link, but a few on here said i should make it a straight link for calculation purposes. so it doesnt actually bind up.
i have been trying to calculate this with all the help, but i still cannot come up with a resonable force in the...
its hard to show the load of 4000kg rb, as its basically sitting on top of the link B. the actuator is trying to rotate the link B which goes through a turntable with a mass on top of it.
my linkage is in effect being opposed by a dead load sittin on link B
i have attached a DWG file for...
i basically chose this ram as i had a determined space to fit my mechanism within. this hydraulic ram with a 6oomm stroke allowed me to rotate this linkage through my required 180degrees.
the maximum retraction force this ram can provide is the 53KN i have illustrated (just a starting point i...
