Improvements in Machines for Trenching, Grooving and Cutting Slots in Wood, Metal, and the like.
Year: 1897

page_text: Date of Application, 1st July, 1897
Complete Specification Left, 1st Apr., 1898-Accepted, 1st July, 1898
Improvements in Machines for Trenching, Grooving and Cutting
Slots in Wood, Metal, and the like.
WILLIAM BRIDGEWATER, 25, East Bond Street, Leicester, in the County of
Leicester, Engineer and Machinist, do hereby declare the nature of this invention
to be as follows:-
:-
This invention relates to the construction of a machine for cutting the trenches
for stairs grooves for shelves, slots and undercutting for doveingtailling and slides
like the slides of a slide rest lathe and for many other purposes.
To effect my purpose I construct a machine with an arm capable of complete or
partial revolution round a centre supported by the frame of the machine and
capable of virtical adgustment.
The arm carring a saddle or slide to which is attached suitable bearings to
carry a virtical shaft or spindle to the bottom of which spindle is attached the
cutters.
The arm is capable of being set to any angle suitable for stair trenching or other
purposes the saddle or slide is carried along the arm by a screw or other suitable
means and can be carried past the centre of the radial movement of the arm to
cut the nosings of stair trods.
The arm can be set in any position to cut grooves or slots as required.
The cutting tool is made with one or more cutting edges as required.
A movable stop regulates the depth of cut.
I purpose driving the cutter spindle by a flexable shaft or belt pulleys attached
to arms hinged together by the centre pulley axle thereby giving free travel to the
cutter in any required direction.
Dated this 30th day of June 1897.
+
Improvements in Machines for Trenching, Grooving and Cutting
Slots in Wood, Metal, and the like.
I, WILLIAM BRIDGEWATER, of 25, East Bond Street, Leicester, in the County of
Leicester, Engineer and Machinist, 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:-
C
This invention relates to the construction of a machine for cutting the trenches,

page_text: the eccentric is made of a circular peice of metal an oblong hole in it B³ a handle B6
is formed on the eccentric in the position shewn in Fig. 13. Sa is a sleeve that
fits on the stud B³ the sleeve has a flange formed on one end the other end has a
screw cut on it to receive a nut B7 Fig. 13. The sleeve is now put on the stud B³
and the eccentric B is placed over the sleeve a washer is put on and the nut screwed
on, if the eccentric is raised so that the sleeve is at the bottom of the oblong slot
and the nut screwed home the whole becomes practically a solid eccentric, on
stud B³ the amount of eccentricity is regulated by the position of sleeve in the
oblong slot the lock nuts 138 and washer keeping the eccentric in its place on the
stud B³.
To better make my invention understood and the working of the machine I
describe it as cutting the grooves in the string of stairs taking the pitch at 50° zero
being the front of the machine marked on the flange 11 of head 4 and the degrees
marked each way, as shewn by the pointer Fig. 14, the nuts of the tee headed bolts
are loosend and turning the part of the machine 5 carrying with it the plate 10
untill pointer reaches 50° which is then made fast by the nuts, and the tool 29 is
carried past the axis of the shaft 5 as much as is required for the nosing of the
stair trod, the depth of the cut haveing been regulated by the stop (to be hereafter
described) the nosing is then cut and the tool 29 is carried by screw 32 Fig. 1 cuts
the groove across the string at the above angle.
The wedge place has now to be cut in the travil back of the slide carrying the
cutting tool; the thickness of the wedge is regulated by the eccentricity given,
as explained in describing Figs. 13 & 14. Now by turning the handle of the
eccentric to the left it will turn the shaft and slide connected to it to the left also;
that alone being moveable as the plate 10 and pointer is rigidly bolted to the
head 4 as before described; the sleeve 23 Fig. 3 is now lowered taking down the
cutter 24 which is of such a shape that it undercuts the amount required this cutter
is so adgusted that it can only be lowered to the depth of groove already cut,
in travilling back to cut for the wedge the material only on one side of the groove
is taken away, and as the tool travils radially a wedge shape must be cut away;
and the cutter will have reached the axial line the sleeve 23 is raised lifting the
cutter 24 out of action the nuts of the tee bolts are again loosened and handle of the
eccentric turned down, by now turning again the part 5 of the machine till
the pointer as passed zero and reached 40° the nuts are again screwed tight and the
operation of cutting a groove for the riser the cutter will now travil across the
string at the above angle making a right angle with the groove previously cut
and the operation of cutting the wedge place is the same only the eccentric handle
is turned to the right instead of the left so that both the wedge places are on the
inside and both of one size; the string is now moved along the required distance to
cut the grooves for the next step.
3 Fig. 2 is a moveable table which can be removed when required, 20 Fig. 2 is
an adgustable cramp which can be removed also when required.
Fig. 3 shews the bottom of cutter spindle 15, with chuck 22 attached and
sleeve 23 the sleeve has a projection 25 to which is attached adjustably by bolts in
slots 28 the side or undercutting tool 24.
Fig. 4 is a virtical section of Fig. 3 the slots for the bolts are horizontal and
slots in the cutter 24 are virtical which allows of sufficent adjustment.
Fig. 5 is a section of sleeve to shew the projection 25.
Fig. 6 is a sectional view of stop which can be adjustably attached to slot in
virtical attachment 31 Fig. 1. 31 Fig. 6 is a section of the sides of the slot 31
Fig. 1 and 26 Fig. 6 part of lever 26 Fig. 1 so that the action may be easily
understood, the body of the stop is formed with a flange to rest on both sides of
piece slotted and screw cut on the body to receive nut a² & washer to screw
against the back of the sides of slot, so that it can be fixed in any position along
the slot; the body a³ of the stop is drilled out two sizes to form a base for the
spring a to rest upon; the stop itself has a pointed end it is reduced at the other
end for about two thirds its length to pass through the spring a¹ and form a

page_text: shoulder for the spring to press against and the small end to pass through the
small hole in the body, the spring is prevented from pushing the stop out too far
by pin through the small end of stop; the lever 26 has a hole in it corrisponding
to the hole in which the stop works, and the sides of the lever at that point are
bevilled so when the lever 26 is brought to the stop a³ it presses the stop in and
compressing the spring at untill the hole in the lever comes over the stop which it
immediately enters by the action of the spring and holds the lever firm. To release
the lever a spring a is attached to the lever to which spring is attached a stud ar
fitting in the hole in the lever, by pressing the stud in the stop is pushed back
and the lever can be moved up or down as required. It will be seen that by
placeing two stops in the slot of 31 one will regulate the depth the tool is to go,
and the other will hold it up out of the work at any position required. To ensure
the hole in the lever coming exactly over the stop a suitable guide may be placed
on the lever, or the lever may have the stud or pin on which the. other end of the
lever 26 works a fixture so the hole carring stud a7 will move in a circular direction,
and the slot in the peice 31 made to corrispond.
This arrangement of stops is especially useful in cutting the trenches of the
strings of stairs.
Fig. 7 is a form of double edge cutter of which Fig. 8 is a section on line CD
which sectional shape is maintained from i to j one side with cutting edge is then
turned under at right angles with i j as shewn at a Figs. 7 & 8 same as cutter 29
Fig. 3.. This under edge is necessary to cut away the material as the cutter enters
and to make a clean bottom to the grooves when cut. The cutter Fig. 7 is prefer-
able for deep cutting such as morticing and the like.
The cutting tool may be twisted like a twest bit but retaining its cutting edge
up the twist edge and at the bottom as above described Fig. 12 shewes a means of
driving the tool by belt pullies, a belt connect pullies 1 & 2 which are held at
a suitable distance by axle bearings d, d and connecting rod 3*, 3, pulley 1 is
attached to axle 17" Figs. 1 & 2 in place of flexable shaft 16 Figs. 1 & 2 a belt
also connects pullies 3 & 4* these pullies are also kept at the required distance by
bearings 5 & 6* and connecting rod 7, 7, pulley 4* has a fixed feather key in
it to slide up virtical shaft S¹ a forked bracket attached in a suitable position to
the head 4 Fig. 1 & 2 carries the pulley 4* and connections up or down the virtical
shaft Sas-the head is carried up or down by the screw & bevil wheels Fig. 11 to suit
the different work required.
The pullies 2 & 3 are in one casting an axle passes through bearing 5* and
through the pullies 3 & 2* into bearing d in which it is secured by set-screw d
thereby forming hinge so that the pullies 1 & 4 can be brought together or opened
out without interfering with the action of the belts in driving the tool in whatever
position it may be in in being carried by the slide in the different parts of the work
to be performed.
When a flexable shaft is used which I prefer as it as less friction, the flexable
shaft 16 Figs. 1 & 2 is coupled to the axle 17 of wheel 17 the other end of
flexable shaft is coupled to axle of wheel a² gearing with wheel a³, wheel ³ is
driven by virtical shaft S by means of a feather key fixed wheel a sliding in key
groove in shaft S, the bearings at of the wheels a² & being attached to the head 4
Fig. 2 are carried up and down the shaft S as the head is raised or lowered therefore
not interfering with the working of the flexable shaft.
The virtical shaft S is driven by any suitable means according to the circum-
stances of where the machine is placed.
15 Figs. 1, 2, 3 & 4 is the spindle to which the cutters are attached, the spindle
has a key groove cut in it a feather key fixed in pinion 18 by which the spindle
is driven and the key groove enables the spindle to pass up and down through the
pinion 18 which wheel is driven by wheel 17 and flexable shaft or other suitable
means.
Refering to Figs. 9 & 10 shew a plan of adgustable cutter to cut holes or groove
of various sizes within certain limits, the shank of the, cutter being held in a hole

page_text: in the chuck drilled eccentrically to the axis of the spindle, by turning the cutter c
from a in the direction of the arrow, it will be seen as the chuck revolves round the
centre S³ any variation of the cutter between a & b will make a corresponding
difference in the size of the hole or groove cut.
It will be seen that the machine though discribed more especially for trenching
string of stairs as best to illustrate the action of the machine that by having suitable
cutters it is capable of a wide range of work in wood or metal and the like.
Having now perticularly discribed the nature of my said invention, and in what
manner the same is to be performed, I declare that what I claim is:-
1st. Improvements in machinery or apparratus for cutting housing or trenching
strings of stairs tennoning grooving for shelves and the like and many other pur-
poses such as herein described and illustrated consisting essentially of a virticul
spindle carring suitable cutters and capable of traversing in almost any direction
and at almost any angle and also capable of crossing the centre on which the slide
arm is made to revolve substantially as herein set forth.
2. The combination of cutters as shewn in Figs. 3 & 4 for cutting housings or
trenches and undercutting the side for receiving the wedge as herein set forth and
parts connected therewith and mechanism substantially as described.
3. The arrangment and combination-constituting a complete machine for
grooving and the like, the whole operating substantially and for the purpose as
herein discribed.
1000