Mechanics of gliders vs rocking chairs
Mechanics of gliders vs rocking chairs
(OP)
There's a slow motion discussion on Wikipedia about how a glider works versus a rocking chair. See: h ttp://en.w ikipedia.o rg/wiki/Ta lk:Glider_ (furniture)
Are gliders deliberately designed to move like a rocking chair or is the design intent to make the motion different?
Thanks.
Sam.
Are gliders deliberately designed to move like a rocking chair or is the design intent to make the motion different?
Thanks.
Sam.





RE: Mechanics of gliders vs rocking chairs
The question isn't something that anyone other than the designer can really answer. It's like asking if a flat head screwdriver was intended to open a can of paint.
RE: Mechanics of gliders vs rocking chairs
Tobalcane
"If you avoid failure, you also avoid success."
RE: Mechanics of gliders vs rocking chairs
Sam.
RE: Mechanics of gliders vs rocking chairs
Yes, only if:
1) all the bars are the same length
2) all the lower pivots are on a plane which is parallel to the floor
3) all the upper pivots are on a plane which is parallel to the floor
ISZ
RE: Mechanics of gliders vs rocking chairs
My glider has a bottom link that's about 3 inches shorter than the top link. The side links are only about 1/3 as long as the top link
TTFN
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RE: Mechanics of gliders vs rocking chairs
e.g. See: h
"A glider is an updated version that's designed to slide forward and backward rather than rock in an arc".
See also: htt
"Unlike swings and rocking chairs, gliders have no arc to their movement; instead, they move on a flat plane."
Sam.
RE: Mechanics of gliders vs rocking chairs
Yes, it is an updated version of a rocking chair, but as Twoballcane said, it's much easier on the floor and has a less-pronounced "rock". And the motion does describe an arc or some single line curve; depending on the following....
The basic layout of the linkages is a trapazoid; however, the lengths of the "opposite" side links and upper/lower members as well as the mounting points can be varied to change the path of the seat.
On a typical glider, if you made a small X on the side-board, then watched it through the forward-rearward motion of the seat, you'll see it describe an arc or curve.
It would not be an ellipse or some other closed-end curve because the forward displacement is the same as the rearward.
Here's a Patent that shows a basic layout.
On the first page, there are many more Patents which can be viewed on Google's patent site.
RE: Mechanics of gliders vs rocking chairs
a parallelogram will describe a straight or level forward-rearward motion; however it will change a fixed point on the moving member in the vertical distance, thus describing an arc.
RE: Mechanics of gliders vs rocking chairs
That said, there is probably no consensus in the actual particulars of the gliders on the market. There will be some where strict parallelograms are used, and there will be others where a rhombus is used.
TTFN
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RE: Mechanics of gliders vs rocking chairs
Sam.
RE: Mechanics of gliders vs rocking chairs
Given the lack of intimate knowledge in an audience of engineers, why would you think there were any customer influence?
TTFN
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RE: Mechanics of gliders vs rocking chairs
Sam.
RE: Mechanics of gliders vs rocking chairs
RE: Mechanics of gliders vs rocking chairs
The glider can do whatever you want it to do, within limits, as you select the arrangement of the four links.
Ted
RE: Mechanics of gliders vs rocking chairs
Sam.