Improvements in Drop Forging Hammers or Stamps.
Year: 1893

page_text: Date of Application, 6th Sept., 1893
Complete Specification Left, 28th May, 1894-Accepted, 30th June, 1894
PROVISIONAL SPECIFICATION.
Improvements in Drop Forging Hammers or Stamps.
I JAMES ROBSON Junior of 48 Linwood Road, Handsworth, in the County of
Stafford, Mechanical Engineer do hereby declare the nature of this invention to be
as follows:-
My invention relates to that class of drop forging hammers or stamps in which
a band having one end fixed to a tup or falling weight is passed over a revolving
pulley and an attendant upon taking hold of the loose end can by pulling cause the
belt to adhere to the pulley and raise the tup. On releasing the band the tup
will by its own weight descend and strike the anvil or die. And has for its object
to dispense with the services of this attendant and render it such that the person
using it may raise and drop the tup without any assistance and with certainty of
action. In cases however where it is desirable to have a separate attendant an
arrangement is made so that it may be worked by one.
This invention will be readily understood from the following description.
Between two vertical standards and at their lower ends an anvil with block or die
is fixed. On the top and between the standards are two pulleys carried on shafts
supported in bearings. The larger one over which the band from the hammer tup
is passed being called the lifting or raising pulley and the smaller one which runs
loose on an eccentric shaft being called the friction pulley.
The raising pulley is continuously revolved in one direction by means of a
driving pulley fixed on the outer end of the shaft. And when the friction pulley
by means of suitable levers and the eccentric shaft is pressed against the lifting
band it brings it in contact with the lifting pulley. The resulting friction causing
the band to adhere which is then turned round with it at the same time lifting the
tup until the friction pulley is moved out of contact when the tup will fall again by
its own weight or if only just sufficient pressure be kept on the lifting band by the
friction pulley the tup will remain almost stationary at any position desired.
When an even or flat lifting band is used it will require a rather fine adjustment
to be made when it is desired to keep the tup at any particular height.
To overcome this I propose to make the lifting band taper that is the end nearest
the tup will be of less thickness than the opposite end. The result of this will be
that when the friction pulley is brought to within any desired distance of the lifting
pulley the tup will be raised until the thickness of the tapering lifting band shall
be about equal to the distance between the two rims of the lifting and friction
pulleys, when the tup will come to rest and remain so until it is desired to further
raise it or let it fall.
The lifting band can either be a specially built up one of leather an ordinary
link band or a woven cotton band made in a suitable manner so as to have the
necessary taper. At the same time I do not bind myself to any particular material
of which the band may be manufactured as any band of a sufficiently flexible
material would answer the same purpose.
It may also be necessary to provide against carelessness by keeping the friction
pulley in contact with the band too long and bringing the tup over the top of
lifting pulley. This 1 do in two ways firstly by placing a projection on the tup
which comes in contact with a lever when a proper height has been reached and
moves the friction pulley out or partially out of contact with the lifting band

page_text: Secondly by forming a depression on the lifting band of sufficient depth so that the
greatest range of the friction pulley will not be sufficient to bring this thinner part
of the lifting band into contact with the raising pulley.
It must also be understood that I do not confine myself to the eccentric shaft
for bringing the friction pulley into contact with the lifting band, and that any
mechanical means may be utilized to attain the same end, such as wedges screws or
other mechanical arrangements.
Instead of the tup having to be raised before each blow the friction pulley can
be arranged to be always in contact with the lifting band and so keep the tup
suspended. When a blow was desired the friction pulley would be moved out of
contact with the lifting band allowing the tup to fall and remaining down until the
friction pulley was released when it would come into contact again with the lifting
band and raise the tup where it would remain until again released.
Dated this Fifth day of September 1893.
COMPLETE SPECIFICATION.
Improvements in Drop Forging Hammers or Stamps.
1 JAMES ROBSON Junior of 48 Linwood Road Handsworth in the County of
Stafford Mechanical 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:-
My invention relates to that class of drop forging hammers or stamps in which a
flexible band having one end fixed to a tup or falling weight is passed over a revolving
pulley and an attendant upon taking hold of the loose end can by pulling cause the
band to adhere to the pulley and raise the tur. On releasing the band the tup
will by its own weight descend and strike the anvil or die. And has for its object
to dispense with the services of this attendant and render it such that the person
using it may raise and drop the tup without any assistance and with certainty of
action.
In order that my invention and the manner of performing the same may be
properly understood I hereunto append a sheet of explanatory drawings to be
herein after referred to. In these drawings the same reference figures are used to
mark the same or like parts wherever they are repeated.
Figures A and B shew side and front elevations of a drop hammer or stamp, 1 is
the anvil block and base on which are fixed the vertical guides 2 the upper part of
the guides being held in position by stay rod 3. Working with its periphery on
about the centre line of the anvil or die 12 in Figure A and on the centre of the
hammer or stamp in Figure B is a large flanged lifting pulley 4 which is fixed to
and carried on a shaft 5 supported in bearings 6. The lifting pulley 4 is
continuously revolved in the direction of the arrow by means of the driving pulley 7
which is connected by a belt to line or other shafting. Cast on the tup 8 are two
bosses to which is attached by means of a pin 9 one end of the flexible lifting
band 10 which passes over and between the lifting pulley 4 and friction pulley 14.
The top anvil or die 11 is shewn driven into the tup 8 and held by a taper pin the
bottom anvil or die 12 being held to the anvil block 1 in the same manner.
Of
course any other known methods may be used to hold the anvils or dies in position.
The handle 13 is for supporting the tup 8 above the bottom anvil or die 12.
When
the tup 8 is raised the handle 13 by its own weight falls down, its opposite end being
moved clear of the tup 8 which can now descend and strike the bottom anvil or
die 12.
On one side of the periphery of the lifting pulley 4 is a second smaller friction
pulley 14 which runs loose on an eccentric shaft 15 supported in bearings 16 keyed on

page_text: to the eccentric shaft 15 is a lever 17 connected to a rod 18 the lower end of which is
connected to a lever 19 keyed to a weigh shaft 20 fixed to the weigh shaft 20 is a
treadle or foot lever 21 arranged so that it can be readily worked by foot. The
right and left hand threaded nut 22 is for adjusting the length of the rod 18.
The action of the hammer or stamp is as follows:-When the person using it
presses with sufficient force on the treadle or foot lever 21 it by means of the
weigh shaft 20 lever 19 rod 18 and eccentric shaft lever 17 turns the eccentric
shaft 15 partly round causing the friction pulley 14 to press the lifting band 10
against the lifting pulley 4. The resulting friction causes the lifting band 10 to
adhere to the lifting pulley 4 which is then turned round with it at the same time
lifting the tup 8 until the treadle or foot lever 21 is allowed to come back to its
original position which it does by means of the weight of the rod 18 at the same
time moving the friction pulley 14 out of contact with the lifting band 10 when
the tup 8 will fall again by its own weight and strike the anvil or die.
When an even or flat lifting band is used such as shewn in Figure A it will
require a rather fine adjustment of the treadle or foot lever 21 to be made by the
person using the hammer or stamp when it is desired to keep the tup 8 suspended
at any desired height. To overcome this I propose to make the lifting band 10
taper as shewn in Figure C. that is the part passing between the lifting pulley 4
and the friction pulley 14 shall have the end nearest the tup 8 of less thickness than
the opposite end. The result of making the lifting band 10 taper will be that when the
friction pulley 14 is brought to within any desired distance of the lifting pulley 4
the tup 8 will be raised until the thickness of the tapering lifting band 10 shall be
about equal to the distance between the two rims of the lifting pulley 4 and the
friction pulley 14 when the tup 8 will come to rest and remain so until it is desired
to further raise it or let it fall.
It may also be necessary to provide against the friction pulley 14 being kept in
contact with the lifting band 10 too long and bringing the tup 8 over the top of
lifting pulley 4.
This I do in two ways, firstly a lever 23 is supported on the stay rod 3 Figures A
and B one end of which engages with the rod 18 by means of the fixed collars 24
sliding collar 25 and spring 26 the other end of the lever 23 being of sufficient
length to allow of its being moved by the projection 27 on pin 9 fixed on tup 8.
Should the treadle or foot lever 21 be depressed with sufficient force too long the
tup 8 will be lifted until the projection 27 of pin 9 comes in contact with the
lever 23 and by means of rod 18 and lever 17 move the friction pulley 14 out of
contact with the lifting band 10 or allow just sufficient contact with the lifting
band 10 to keep the tup 8 suspended. The spring 26 is for taking up any sudden
knock on the rod 18.
Secondly by forming a depression 28 on the lifting band 10 Figures A. B. and C
of sufficient depth so that the greatest range of the friction pulley 14 will not be
sufficient to press this thinner part 28 of the lifting band 10 into contact with the
lifting pulley 4.
Should it be desirable to work the hammer or stamp by a separate attendant a
hand lever 29 is shewn in Figures A and B supported by a bracket cast on one of
the vertical guides 2 and by means of a pin and slot 30 is connected to the
rod 18.
When the attendant presses one end of the hand lever 29 down the rod 18 and
lever 17 are raised causing the friction pulley 14 to come into contact with the
lifting band 10 and press it against the lifting pulley 4 the same operation taking
place as before described with reference to the treadle or foot lever 21.
In Figure A a regulating stop 31 is shewn fixed in the anvil block and base 1 so
that any desired lift can be given to the rod 18.
Figure C illustrates a modification of the herein before described drop hammer
or stamp in which modification the tup 8 is arranged to be suspended as shewn in
dotted lines.

page_text: The arrangement and action is as follows:-The lifting pulley 4 and friction
pulley 14 are arranged in the same manner as shewn in Figures A and B but the
eccentric shaft lever 17 and upper end of rod 18 are arranged on the opposite side
of eccentric shaft 15 in Figure C to that shewn in Figure A. The lower end of
rod 18 has one end of a spring 32 secured to it by an eye bolt 33 the other end of
the spring 32 is fixed to the anvil block and base 1 by another eye bolt 34.
The lower end of rod 18 is connected to a lever 19 which is keyed to a weigh
shaft 20 fixed to the weigh shaft 20 is a treadle or foot lever 21 arranged so that
it can be readily worked by foot. As long as the treadle or foot lever 21 is kept
depressed as shewn in Figure C it by means of the weigh shaft 20 lever 19
rod 18 and eccentric shaft lever 17 prevents the friction pulley 14 pressing the
lifting band 10 against the lifting pulley 4. On releasing the treadle or foot
lever 21 the spring 32 will pull the rod 18 and eccentric shaft lever 17 downwards
and by means of the eccentric shaft 15 and friction pulley 14 press the lifting
band 10 against the lifting pulley 4 until the tup 8 has been raised to the position
shewn in dotted lines Figure C when the depression 28 of the lifting band 10 will
have come between the lifting pulley 4 and friction pulley 14. And as the eccentric
shaft 15 and friction pulley 14 cannot travel any closer to the lifting pulley 4 by
reason of the treadle or foot lever 21 coming into contact with the top of the
opening 35 in the anvil block and base 1. The tup 8 will remain suspended as
shewn in dotted lines until the treadle or foot lever 21 is pressed down when the
lifting band 10 will be released and the tup 8 will by its own weight fall and strike
the anvil or die.
The flexible lifting band 10 can either be a specially built up one of leather an
ordinary link band or a woven cotton band made in a suitable manner so as to have
the necessary depression 28 and taper as shewn in Figure C or the necessary
depression 28 only in an even or flat lifting band as shewn in Figure A. At the
same time I do not confine myself to any particular material of which the lifting
band 10 may be manufactured, as any suitable material of a sufficiently flexible
nature will answer the same purpose.
I wish it to be understood that the tapering lifting band 10 as shewn in Figure C
can be used on the hammer or stamp Figure A in place of the even or flat lifting
band 10 which can be used on the hammer or stamp Figure C. Neither is it
necessary that the flexible lifting band 10 Figure C be taper over all the length
which passes between the lifting pulley 4 and friction pulley 14. The taper need
only extend over that portion which is necessary to carry out the object of being
able to regulate the height at which it is desired to keep the tup 8 suspended the
other portion of the lifting band 10 may be of an even or flat section.
It must also be understood that I do not confine myself to the eccentric shaft 15
for bringing the friction pulley 14 into contact with the lifting band 10 and that
any mechanical means may be utilized to attain the same end such as wedges screws
or other mechanical arrangements.
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. In drop hammers or stamps the combination of a lifting pulley and friction
pulley the latter being mounted on an eccentric shaft and arranged so that it can
be moved into and out of contact with a flexible lifting band by suitable levers
substantially as described.
2. In drop hammers or stamps an even or flat flexible lifting band of any suitable
material with a depression at any desired position which is caused to adhere to a
lifting pulley by means of a friction pulley substantially as described.
3. In drop hammers or stamps a tapering flexible lifting band of any suitable
material with a depression at any desired position which is caused to adhere to a
lifting pulley by means of a friction pulley substantially as described.

page_text: 4. In drop hammers or stamps the arrangement of levers, lifting pulley and
friction pulley in combination with a flexible lifting band of an even or tapering
section with a depression at any desired position whereby the tup is raised and
remains suspended until released substantially as described.
Dated this 24th day of May 1894.
JAMES ROBSON, JUNIOR,
Applicant.