Improvements in Pneumatic Machines for Cutting off the Ends of Bolts, Rods, and the like.
Year: 1898

page_text: Date of Application, 10th Jan., 1898-Accepted, 5th Mar.,
1898
COMPLETE SPECIFICATION.
Improvements in Pneumatic Machines for Cutting off the Ends of
Bolts, Rods, and the like.
-
I, REGINALD HADDAN, of the Firm of Herbert Haddan & Co., of 18, Buckingham
Street, Strand, W.C., Patent Agent, do hereby declare the nature of this inven-
tion, a communication to me from abroad by James Whitelaw, of 1057 Monadnock
Building, Chicago, Illinois, United States of America, Manufacturer, 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 improvements in pneumatic bolt-cutters, being a machine
consisting essentially of a pair of levers provided with cutting jaws and operated
by a piston within a cylinder, by means of which the jaws may be forced together
to cut off the end of a bolt. or rod inserted between them. The novelty of my inven-
tion will be hereinafter set forth and particularly pointed out in the claims.
In the accompanying drawings Figure 1 is a side elevation of the complete
machine; Figure 2 a bottom-plan view of the machine as shown in Figure 1;
Figure 3 a vertical section on the line 3-3 of Figure 1; and Figure 4 an enlarged
cross-section of the valve on the line 4-4 of Figure 3.
The same letters of reference are used to indicate corresponding parts in all the
views.
A and B represent a pair of levers suitably hinged together near their front ends
at C. The rear end of the lever A is hinged to the upper side of a cylinder D
as shown at E in Figure 3, while the rear end of the lever B is hinged at F,
Figure 1, to the lower end of the rod G of a piston H fitting within the cylinder D.
A valve casing I is secured to the upper side of the cylinder 1), and the chamber
within it communicates with the opposite ends of the cylinder D) by means of
passages JK, the former being formed within a rib L upon the wall of the
cylinder. The motive fluid enters the valve chamber from a supply-pipe M, and
is directed alternately to the opposite sides of the piston H within the cylinder D
by means of a valve N within the casing I, as hereafter described.
At their forward ends the levers A and B are provided with sockets in which
are fitted removable cutters A¹ B₁ having their outer ends suitably shaped to form
inwardly projecting cutting-jaws adapted to be forced together when the rear ends
of the levers A B are spread apart, to bite off the end of a bolt or rod inserted
between them. These cutters A¹ B¹ are held in their sockets in the ends of the
levers A B by suitable set-screws a.
Under the foregoing construction and arrangement of parts, when the valve N
is turned to admit motive fluid to the upper side of the piston H in the cylinder D
said piston will be forced downward in said cylinder (to the left in Figure 3)
thereby spreading apart the rear ends of the levers A and B and forcing together
the cutters A B₁ at their forward ends, with the result above stated. Upon turn-
ing the valve to another position the motive fluid at the upper side of the piston H
will be permitted to pass backward through the port K, thence through the valve
to the passage J, and thence to the under side of the piston H, thereby balancing
the pressure upon the opposite sides of the piston H. A further movement of the

page_text: valve will open the exhaust from the upper side of the piston H, and permit the
pressure beneath it to restore it to normal position preparatory to another operation.
The arrangement and co-operation of the ports and passages by means of which
the valve N thus controls the admission and exhaust of the motive fluid at the
opposite ends of the cylinder may be understood by reference to Figures 3 and 4.
The port by which the motive fluid enters the valve-casing from the supply-pipe M
is shown by dotted lines at 6 in Figure 3. As also shown by dotted lines in the
same figure and by solid lines in Figure 4, the valve N is provided on one of its
sides with a longitudinal recess or passage c, which, when the valve is in the
position shown in Figure 3, places the inlet-port 6 in communication with the
passage K leading to the upper side of the piston H. At the same time an
exhaust passage d formed in the upper end of the valve N in
Figure 3 will be in communication with the passage J leading to the
lower or left hand end of the cylinder D, so that the piston H will
be free. to move downward under the pressure admitted to its upper side.
The valve N is further provided with a central longitudinal exhaust passage e
which communicates at its upper end with a radial port f extending outward
through the surface of the valve. The valve is further provided with a longitu-
dinal recess or passage g located upon the side of the valve at a point midway
between the port f and recess c heretofore described, Figure 4.
Now, assuming the parts to be in the position shown in Figures and 4, the
operation will be as follows:-The piston H will be driven downward in the
cylinder 1 (to the left in Figure 3) by the motive fluid admitted above it from
the supply-pipe M through the port and passage be in the valve N, and through the
inlet-passage K leading to the upper end of the cylinder. Upon now turning
the valve N one-third of a revolution in the direction of the arrow in Figure 4,
communication between the inlet-port 6 and passage K will be cut off, and the
passage K will be put into communication with the passage J by means of the
recess in the valve N. The motive fluid within the cylinder, at the upper side
of the piston, will then pass through K g and J to the under side of the piston,
until the pressures are balanced. Upon then giving the valve a further third of
a revolution communication between the passages K and J will be cut off and the
portf of the exhaust passage e will be brought into register with the passage K,
thereby permitting the pressure above the piston H to escape, whereupon the pres-
sure below it will return the piston to normal position ready for another operation.
At the next third of a revolution of the valve the parts will be brought to the
position shown in Figures 3 and 4, with the result before explained.
For the purpose of turning the valve in the manner above described there is
swiveled upon its reduced lower end or stem a lever or handle O confined by a
nut P. Within this handle is a spring-pressed pawl Q, (dotted lines Figures 1, 2,
and 4,) adapted to co-operate with notches R in a flange
upon the valve N,
Figure 3. There are three of the notches R at equal distances apart around the
periphery of the flange S, so that by three manipulations of the handle Q the three
thirds of a revolution of the valve N may be readily given it for the purposes
explained. The notches R have abrupt walls at one side, and inclined walls at the
other, and the end of the pawl carried by the handle O is correspondingly beveled
or inclined, so that when the handle O is turned backward the end of the pawl will
ride freely over the periphery of the flange S, and when the handle is turned for-
ward will engage the notch R in the flange and turn the valve with it.
•
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to performed I declare that what I
claim is:
=
1. A machine of the character described, composed of a pair of levers fulcrumed
near their forward ends and provided with cutting jaws, and a cylinder and piston
co-operating with their rear ends to force the latter apart and bring the cutting
jaws together, for the purpose described.

page_text: 2. A machine of the character described, .composed of two levers fulcrumed near
their forward ends and having cutting jaws, and a cylinder interposed between the
rear ends of the levers, the end of one lever being hinged to the cylinder head and
the end of the other lever being hinged to the projecting end of the piston rod at
the opposite side of the cylinder, substantially as described.
3. A machine of the character described, composed of a pair of levers hinged
together near their forward ends, and provided with cutting jaws, and a cylinder
and piston co-operating with the rear ends of said levers to force the cutting jaws
together, substantially as described.
4. The combination of a pair of levers fulcrumed near their forward ends and
provided with removable cutting jaws, and a cylinder and piston co-operating with
the rear ends of said levers to force the cutting jaws together, substantially as
described,
5. The combination of a pair of levers fulcrumed near their forward ends and
provided with sockets for the reception of removable cutters, a pair of removable
cutters seated in said sockets, and a cylinder and piston co-operating with the rear
ends of said levers to force the cutting jaws of the cutters together, substantially
as described.
6. The combination of a pair of levers hinged together near their forward ends
and provided with removable cutting jaws, and a cylinder and piston co-operating
with their rear ends, to force the cutting jaws together, substantially as described.
7. The combination of a pair of levers hinged together near their forward ends
and provided with removable cutting jaws, and a cylinder interposed between the
rear ends of said levers, the end of one lever being hinged to one cylinder head and
the end of the other being hinged to the end of the piston rod projecting through
the opposite cylinder head, substantially as described.
S. The combination of a pair of levers hinged together near their forward ends
and provided with sockets for the reception of removable cutters, and a cylinder
and piston interposed between the rear ends of said levers, the end of one lever
being hinged to one of the cylinder heads, and the end of the other lever being
hinged to the end of the piston rod projecting through the opposite cylinder head,
substantially as described.
. 9. The combination of a pair of levers fulcrumed near their forward ends and
provided with cutting jaws, a cylinder and piston co-operating with the rear ends
of said levers to force the cutting jaws together, and a valve co-operating with
the inlet and exhaust passages leading to the opposite ends of the cylinder and
operating by successive movements to first open the inlet passage to one side of
the piston and the exhaust passage to the opposite side thereof, to then place the
two sides of the piston into communication with each other to balance the pressure
upon the opposite sides thereof, and to then open the exhaust from the first
mentioned side of the piston to permit the latter to be returned to normal position
by the pressure upon its opposite side, substantially as described.
10. The combination of a pair of levers fulcrumed near their forward ends and
provided with cutting jaws, a cylinder and piston interposed between their rear
ends, the end of one lever being hinged to one cylinder head and the end of the
other lever being hinged to the end of the piston rod projecting through the
opposite cylinder head, and a valve co-operating with the inlet and exhaust passages
leading to the opposite sides of the piston, and operating by successive movements
to first open the inlet passage to one side of the piston, to then place the opposite
sides of the piston in communication with each other to balance the pressure
thereon, and to then open the exhaust from the first mentioned side of the piston
to permit it to be returned to normal position by the pressure on its opposite side,
substantially as described.
11. The combination of a pair of levers hinged together near their forward ends,
and provided with cutting jaws, a cylinder and piston interposed between their
rear ends, the end of one lever being hinged to one cylinder head and the end of
the other lever being hinged to the end of the piston rod projecting through the

page_text: opposite cylinder head, and a valve co-operating with the inlet and exhaust passages
leading to the opposite sides of the piston, and operating by successive movements
to first open the inlet passage to one side of the piston, to then place the opposite
sides of the piston in communication with each other to balance the pressures
thereon, and to then open the exhaust from the first-mentioned side of the piston
to permit it to be returned to normal position by the pressure on its opposite side,
substantially as described.
12. The combination of a pair of levers hinged together near their forward ends,
and provided with sockets to receive removable cutters, a pair of cutters seated in
said sockets and provided with cutting jaws, a cylinder and piston interposed
between the rear ends of said levers, the end of one lever being hinged to one
cylinder head and the end of the other lever being hinged to the end of the piston
rod projecting through the opposite cylinder head, and a valve co-operating with
the inlet and exhaust passages leading to the opposite sides of the piston, and
operating by successive movements to first open the inlet passage to one side of the
piston, to then place the opposite sides of the piston in communication with each
other to balance the pressures thereof, and to then open the exhaust from the
first-mentioned side of the piston to permit it to be returned to normal position
by the pressure on its opposite side, substantially as described.
Dated this 10th day of January 1898