Improvements in Luffing Cranes.
Year: 1890

page_text: Date of Application, 5th Aug., 1890.
Complete Specification Left, 1st May, 1891-Accepted, 6th June, 1:1891
Improvements in Luffing Cranes.co
I, ROGER WRIGHT of the Elswick Works, Newcastle-on-Tyne, Engineer-do
hereby declare the nature of this invention to be as follows:
In lufting cranes the load is generally first raised to the head of the jib and the!
jib afterwards luffed or turned upwards about its pivot, thereby further raising the
load. This latter dift is often unnecessary and causes a waste of power..
According to this invention I provide means of keeping.the.load at approximately
the same height whilst luffing whatever be the inclination of the jib. For this
purpose instead of fastening the end of the lifting chain (after it has passed over
the pulleys of the lifting cylinder) to some fixed point. I attach it to the ram of the
luffing cylinder or to some other moving part of the luffing gear, so that as the jib
is raised by the luffing gear the lifting rope is at the same time paid out and the
load dropped relatively to the head of the jib.
Dated this 5th day of Aust 1900.
CARPMAEL & Co.,
Agents.
COMPLETE SPECIFICATION.
Improvements in Luffing Cranes.
I, ROGER WRIGHT, of the Elswick Works, Newcastle-on-Tyne, 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 :-
In lufting cranes the load is generally first raised to the head of the jib and the
jib afterwards luffed or turned upwards about its pivot, thereby further raising the
load. This latter lift is often unnecessary and causes a waste of power.
According to this invention I provide means of keeping the load at approximately
the same height whilst luffing whatever be the inclination of the jib. For this
purpose instead of fastening the end of the lifting chain (after it has passed over.
the pulleys of the lifting cylinder) to some fixed point I attach it to the ram of the
luffing cylinder or to some other moving part of the luffing gear, so that as the jib
is raised by the luffing gear the lifting rope is at the same time paid out and the
load dropped relatively to the head of the jib.
In order that my said invention may be more fully understood and readily carried
into effect I will proceed to describe the drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a side elevation of a crane constructed according to my invention,
the jib being lowered,
Figure 2 shows the same apparatus with the jib raised.
A is the post. 13 the jib pivotted to the post at A¹. C is the lifting cylinder
and C its ram.
D is the lifting-chain which. passes round pulleys D₁ D¹ on the
lifting cylinder and ram. E is the lufting cylinder and E' is its ram, which carries
a cross-head F working between guides G fixed to the crane post. The chain D
is carried over pulleys D2 D2 and its end is fixed to the cross-head F of the luffing
ram.
H is the luffing chain which passes over a pulley H¹ on the luffing ram its end
being fixed at K to the luffing cylinder.

page_text: In the arrangement shown the variation of the position of the point of attach-
ment to the lifting rope is only equal to the length of the stroke of the lufling ram.
In cases where it is desired to increase this variation the chain may be carried over
pulleys on the luffing cylinder and ram.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
―
1. Luffing cranes in which the end of the lifting chain is fixed to the ram of the
luffing cylinder or to some other moving part of the luffing gear substantially as
described.
2. Luffing, cranes substantially as described and shown in the drawings.
Dated this 25th day of October 1890
ROGER WRIGHT.