Improvements in Rotary Cutters for Leather Work.
Year: 1893

page_text: Date of Application, 8th Aug., 1893
Complete Specification Left, 8th Mar., 1894-Accepted, 14th Apr., 1894
PROVISIONAL SPECIFICATION.
Improvements in Rotary Cutters for Leather Work.
A communication by JAMES WILLSON BROOKS, of Petersham, in the State of
Massachusetts, one of the United States of America.
I ALFRED GEORGE BROOKES of 55 & 56 Chancery Lane, in the County of
London, Chartered Patent Agent do hereby declare the nature of this invention to
be as follows :—
This invention has for its object to improve the construction of rotary cutters
for leather cutting machines.
In this invention there is provided a hollow shaft against one end of which bears
one of the heads or plates of the cutter, the other head or plate receiving through
it a clamping bar, preferably hollow and provided internally at its inner end with a
screw thread into which is turned a screw inserted from the opposite end of the
hollow shaft, said screw in its rotation into the bar causing the two heads of the
cutter to clamp the blades between them, and also cause the inner head to be locked
to the said sleeve.
It is frequently necessary to change one cutter for another to give to the article
being made the desired configuration, for it will be understood that the width of
the blade and the particular configuration of its front or cutting edge is made to
determine the shape of the cut.
It is aimed to produce a cutter, which, with but slight changes and adjustments
may be made to receive blades of different width and to hold them at any desired
angle.
Ordinarily the side edges of the blades enter straight sided or dovetailed grooves
in the disks holding them, the grooves being purposely so constructed as to preclude
the possibility of the blade tipping in the direction of its width.
In my correspondent's experiments to cheapen the construction and increase the
working capacity of the cutter-heads, he discovered that he might so make the
grooves in the blade-holding disks or plates, and the side edges of the blades to
enter them that the blades would co-operate with disks of different diameter, and
might be adapted to occupy more or less angular positions from side edge to side edge.
To do this, he has made each side edge of the blade as a quarter circle and
the groove in the disk or plate is in cross section of substantially the same
shape.
The sleeve has at one end a flange or enlargement, against which bears the
rear side of the inner head of the cutter, the heads being both grooved at their
inner sides to receive the blades.
There is a locking device between the inner head and the flange or enlargement,
it being a pin or projection on one entering a hole in the other.
The outer head is chambered at its centre to receive the head of a clamping bar,
preferably hollow, and provided with an internal thread which is engaged by a
screw having a collar to abut against the end of the sleeve, the screw having a
suitable wrench head, the rotation of the screw to turn it into the bar drawing all
the parts firmly together.
The bar is provided with a groove, in the outer end of which is secured a key, it
entering a notch or key-seat in the cylindrical opening at the central part of the
outer head, thus keying said head upon the bar.
The inner head at its central opening is provided with a key which also enters
the groove, thus fixing the inner head upon the bar.

page_text: It will thus be understood that both heads are dogged or keyed to the bar,
and that the inner head is connected with the sleeve by a locking device, thus
restraining all tendency to independent rotation of any of the named devices.
The head of the bar referred to, is made in two parts, made spherical at their
inner sides, which receive two concavo-convex shells, which latter receive the
T-headed inner end of a shaft which may be formed corresponding with the shaft 38
used in the Specification of Patent No. 13470, Aug. 27, 1889, it being used to
rotate a rand cutter as provided for in said Patent.
To adjust the blades simultaneously, the cutter is provided with an adjusting
device, having horns, which act against the inner ends of the blades, the adjusting
device being locked in position by suitable screws.
The side edges of the blades are shaped to prevent substantially one-fourth of a
circle, said edges entering grooves in the disks or heads, of suitable shape and size
to receive said substantially quarter round edges and let them tip or turn therein
yet be held firmly, the grooves in the head also being substantially quarter round
in cross section.
In head the outer and inner walls of the groove are preferably made tapering so
as to act as a wedge against the edge of the blade entering it, the blade not
bottoming in the bottom of the said groove.
From the foregoing, it will be understood that the blades would work just as well
if the grooves in the heads were nearer or farther from the centre of rotation of
the shaft, the quarter round edges of the blades entering the groove in the inner
head being free to tip or rock therein as the wedge-like sides of the groove in the
outer head act on the other side edge of the blade.
Dated the 4th day of August 1893.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Rotary Cutters for Leather Work.
A communication from abroad by JAMES WILLSON BROOKS, of Petersham, in the
State of Massachusetts, one of the United States of America.
I ALFRED GEORGE BROOKES of 55 & 56 Chancery Lane, in the County of
London, Chartered Patent Agent 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 has for its object to improve the construction of rotary cutters for
leather cutting machines.
In this invention there is provided a hollow shaft against one end of which bears
one of the heads or plates of the cutter, the other head or plate receiving through
it a clamping bar, preferably hollow and provided internally at its inner end with a
screw thread into which is turned a screw inserted from the opposite end of the
hollow shaft, said screw in its rotation into the bar causing the two heads of the
cutter to clamp the blades between them, and also cause the inner head to be
locked to the said sleeve.
It is frequently necessary to change one cutter for another to give to the article
being made the desired configuration, for it will be understood that the width of
the blade and the particular configuration of its front or cutting edge is made to
determine the shape of the cut.
It is.aimed to produce a cutter, which, with but slight changes and adjustments
may
be made to receive blades of different width and to hold them at any desired

page_text: Ordinarily the side edges of the blades enter straight sided or dovetailed grooves
in the discs holding them, the grooves being purposely so constructed as to preclude
the possibility of the blade tipping in the direction of its width.
In my correspondents experiments to cheapen the construction and increase the
working capacity of the cutter-heads, he discovered that he might so make the
grooves in the blade-holding discs or plates, and the side edges of the blades to enter
them that the blades would co-operate with discs of different diameter, and might
be adapted to occupy more or less angular positions from side edge to side edge.
To do this he has made each side edge of the blade as a quarter circle and the
groove in the disc or plate is in cross section of substantially the same shape.
Fig. 1, in longitudinal section, shews the principal part of a rotary cutter, and
the devices with which it is connected in use.
Fig. 2 shows part of the end of the sleeve and the screw broken off from the
right of Fig. 2.
Fig. 3, a left-hand end elevation of the cutter shewn in Fig. 1.
Fig. 4, a detail of the outer end of the clamping bar, and
Fig. 5, a detail of one of the concavo-convex shells or blocks.
The sleeve A has at one end a flange or enlargement A', against which bears the
rear side of the inner head B of the cutter, the outer head being marked B', the
heads being both grooved at their inner sides to receive the blades a a.
There is a locking device between the inner head and the flange or enlarge-
ment A', it, as shewn, being a pin or projection 6 on one entering a hole in the
other.
The outer head B₁ is chambered at its centre to receive the head of a clamping
bar C, preferably hollow and provided with an internal thread which is engaged
by a screw D having a collar D' to abut against the end of the sleeve A, the screw
having a suitable wrench head D³, the rotation of the screw to turn it into the bar
drawing all the parts firmly together.
The bar C is provided with a groove 4, in the outer end of which is secured a
key 5, it entering a notch or key-seat in the cylindrical opening at the central part
of the outer head B'. thus keying said head upon the bar.
The inner head B at its central opening is provided with a key 15 which also
enters the groove 4, thus fixing the inner head upon the bar.
It will thus be understood that both heads are dogged or keyed to the bar and
that the inner head is connected with the sleeve by a locking device, thus restraining
all tendency to independent rotation of any of the named devices.
The head of the bar referred to is made in two parts, d, d', see Fig. 4, made
spherical at their inner sides, which receive two concavo-convex shells e, e', which latter
receive the T-headed inner end of a shaft f which may be formed corresponding
with the shaft 38 úsed in the Specification of Letters Patent No. 13470, August 27,
1889, it being used to rotate a rand cutter as provided for in said Patent.
To adjust the blades simultaneously, the cutter is provided with an adjusting
device g, having horns g', g', which act against the inner ends of the blades, the
adjusting device being locked in position by suitable screws h, h.
The side edges of the blades are shaped to present substantially one-fourth of a
circle, as best shewn in Figs. 1 and 2, said edges entering grooves in the discs or
heads B, B', of suitable shape and size to receive said substantially quarter round
edges and let them tip or turn therein yet be held firmly, the grooves in the head B
also being substantially quarter round in cross section.
In head B¹ the outer and inner walls of the groove are preferably made tapering
so as to act as a wedge against the edge of the blade entering it, the blade not
bottoming in the bottom of the said groove.
From the foregoing, it will be understood that the blades a, a, would work just
as well if the grooves in the heads were nearer or farther from the centre of rotation
of the shaft A, the quarter round edges of the blades entering the groove in the
inner head B being free to tip or rock therein as the wedge-like sides of the groove
in the outer head B' act on the other side edge of the blade.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
In rotary cutter apparatus for leather work :-
1. The use with a hollow sleeve and heads grooved for the reception of cutter
blades, of an internally threaded clamping bar, and a screw to enter said bar,
and cause it to draw the heads together to clamp the blades, substantially as
.described.
"
2. The clamping bar adapted to occupy a position at the centre of rotation of
the rotary cutter and extend through its blade holding heads, said clamping bar
having a two-part head which is kept closed by entering one of the blade holding
heads, substantially as described.
3. The use with the hollow shaft and clamping bar extended through the heads
of the rotary cutter, of keys to connect the heads and sleeve and prevent the rotation
of the heads independently of the sleeve, substantially as described.
4. A rotary cutter for leather work, said cutter being composed of two heads or
plates having blade receiving grooves and blades entering said grooves, the side
edges of the blades being substantially quarter circular in cross section to enter said
grooves whatever may be the distance of the grooves from the centre of rotation of
the said heads or plates, substantially as described.
5. A rotary cutter composed of a head or plate B having quarter circular
grooves, a head or plate B¹ having grooves with tapered inner walls and blades
having quarter circular side edges, the said heads being mounted upon clamping
devices co-operating with the shaft of the cutter to hold the blades in place,
substantially as described.
11
1
Dated the Tou
7th day of March 1894.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.