Year: 1886

page_text: I WALTER PITT of Newark Foundry Bath, Engineer do hereby declare the
nature of this invention to be as follows:-
This Invention relates mainly to cranes of that class in which a truck or jenny
is mounted upon a horizontal girder or arm and is capable of being traversed to
and fro along it and in which a hoisting chain is led from winding apparatus at
one end of the arm along the arm and downwards over a pulley on the jenny then
around a pulley on the lifting hook and up again and over a second pulley on the
jenny to the opposite end of the horizontal arm to which it is there secured.
In cranes of this kind the chain has to be supported upon roller supports at
intervals apart along the arm and these rollers have to be so mounted that when !
the jenny is traversed along the arm and comes up to any of the roller supports
they move out of the way and allow the jenny to pass. This I effect in the
following manner.
Each roller support extends across the arm and is divided crosswise at its centre.
The axis of each half or length bas a rod or axis extending from its outer end this
is jointed to the top of two parallel links which turn on axes at their lower end
and when turned downwards on these axes act as the links of a parallel rule and
carry the half length of roller away from the other half roller in a direction cross-
wise of the horizontal arm.
ว
A balance weight below the axis of one of the links keeps the links balanced
and another weight passing over a pulley and connected to one of the links tends
always to draw the links into a vertical position. When they are in this position
the two halves of the porter roller butt together end to end and the chain rests,
upon the top of them. When the travelling jenny comes up to or has to move past
the roller support a plough on the jenny acts against the links and turns them
aside so that the two halves of the roller are moved away from one another in
opposite directions and the jenny is free to move past in the space so left between
them.

page_text: I WALTER PITT of Newark Foundry, Bath, Engineer, do hereby declare the
nature of this invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement:-
This Invention relates mainly to cranes of that class in which a truck or jenny
is mounted upon a horizontal girder or arm and is capable of being traversed to
and fro along it and in which a hoisting chain is led from winding apparatus at
one end of the arm along the arm and downwards over a pulley on the jenny then
around a pulley on the lifting hook and up again and over a second pulley on the
jenny to the opposite end of the horizontal arm to which it is there secured.
In cranes of this kind the chain has to be supported upon roller supports at
intervals apart along the arm and these rollers have to be so mounted that when
the jenny is traversed along the arm and comes up to any of the roller supports
they move out of the way and allow the jenny to pass. This I effect in the
following manner.
Each roller support extends across the arm and is divided crosswise at its centre.
The axis of each half or length has a rod or axis extending from its outer end this
is jointed to the top of two parallel links which turn on axes at their lower end
and when turned downwards on these axes act as the links of a parallel rule and
carry the half length of roller away from the other half roller in a direction
crosswise of the horizontal arm.
A balance weight below the axis of one of the links keeps the links balanced
and another weight passing over a pulley and connected to one of the links tends
always to draw the links into a vertical position. When they are in this position
the two halves of the porter roller butt together end to end and the chain rests
upon the top of them. When the travelling jenny comes up to or has to move past.
the roller support a plough on the jenny acts against the links and turns them
aside so that the two halves of the roller are moved away from one another in
opposite directions and the jenny is free to move past in the space so left between
them.
The drawings annexed show a cross section of two horizontal girders forming
part of a crane arm carrying roller supports arranged as above described and also.
shows an end view of the trolly which runs on rails on the top of the girders.
In the drawing the roller on the left hand side is shown in the position it
assumes when moved aside to allow the trolly to pass and on the right hand side
it is shown in its normally closed position when the chain would be resting
upon it.
A A. are the girders-from each an arm B extends outwards and carries the axes
of parallel bars Ⓒ these at the top are jointed to a horizontal rod D which forms an
axis for the roller E. The bars C have also jointed to them another horizontal
rod Fat the end of which is a roller G.
At each end of the trolly is a wedge shaped guard H. As the trolly moves along
the rails and comes up to the roller supports the pointed end of the guard enters
between the rollers & and forces them aside so carrying them into the position
-

page_text: shown on the left hand side of the drawing-this they do readily as the chain
marked I is at this time not bearing upon them but is resting upon the top of one
of the two main guide pulleys J, of the trolly. K is a counterbalance weight for
balancing the bars C and L a weight for bringing back the bars to their normal
position when the trolly has passed so as to bring the roller E back into position
for supporting the chain.
The details of the trolly are not shown as these may be of any ordinary
construction.
Any ordinary winding apparatus can also be used for winding up or unwinding
the chain.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is :-
1. Carrying the chain supporting rollers of traveller cranes by parallel bars to
allow of their being readily moved out of the way of the truck or trolly of the
crane as it moves past them substantially as described.
2. The combination of mechanism for carrying the chain supporting rollers of
traveller cranes substantially as described and illustrated in the drawing annexed.
Dated this 9-1
N1000
CARPMAEL & Co.,
Agents for the Applicant.