Improvements in Apparatus for Outting Teeth in Worm Wheels, and for Milling Out Helical or other Grooves or Slots.
Year: 1894

page_text: Date of Application, 28th Dec., 1894
Complete Specification Left, 30th Sept., 1895-Accepted, 2nd Nov., 1835
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Outting Teeth in Worm Wheels, and
for Milling Out Helical or other Grooves or Slots.
I, WILLIAM MORISON, Manager, Engine Department, of The London &
Glasgow Engineering and Shipbuilding Company, (Limited), 172 Lancefield
Street, in the City of Glasgow, do hereby declare the nature of this invention
to be as follows:-
:-
This invention has for its object to provide a machine for accurately and
inexpensively unlling out or similaily cutting the teeth of worm wheels of any size
and pitch, tho improved apparatus being also applicable for inilling out helical or
other grooves o slots in flat, concave or convex surfaces.
Under the invention the teeth of worm wheels are cut by preference singly, but
it may be several at a time, by means of a rotating milling cutter carried on a
ciank like rocking flame or bar which has imparted to it a motion of partial
rotation combined with an endwise movement sciving to traverse the cutter
through a path corresponding to the space to be formed between the teeth of the
wheel, the spaces being thus cut so as to leave the teeth intact on the wheel im
The rocker bar is carried in bearings upon a stationary framing or on a single or
compound slide and the bar is caused to turn on its axis by means of a worm wheel
on it in gear with a rotating worm carried on the slide this movement being
designed to traverse the milling cutter through an are corresponding to the concave
face of the wheel and the radius of which may be varied being dependent on the
distance of the cutter face from the axis of tho rocker bai, while the cucular
traveise may extend through about 270 degrees when required. The horizontal or
end wise traverse or feed of the rocker bar and the milling cutter carried by it, may
be imparted by a screw fitted ou the end of the rocker and working in a nut fixed
in a biacket on the slide or main framing the pitch of the screw being the same as
that of the woim which is to gear with the wheel being cut; or the feeding
movement may be imparted by other suitable gear. The milling cutter, which 19
preferably of the shape in contour corresponding with the space to be cut between
the teeth, 18 carried on a sprudle fitted in the rocker and driven by a pair of mitre
bevel wheels carried in a bracket formed on fixed on the rocker, one of the bevel
wheels being fixed on an intermediate shaft supported in bearings in the bracket
and in a bracket keyed on the rocker shaft. The intermediate shaft is driven by
apur gearing from a shaft in line with the axis of the rocker so that the driven
wheel moves around the driver.
The worm wheel in which the teeth are to be cut is mounted on a spindle
furnished with dividing mechanism such as is used in cutting ordinary toothed
wheels, the wheel being held stationary while the tooth is cut and moved round
for the succeeding cut, whilst the cutter is out with the wheel.
When the framing or bracket carrying the rocker bar and gear is carried on a
slide a feed gear may be applied to the latter to impart the endwise feeding
movement to the rocker and its cutler.
The teeth in worm wheels may also be cut by this machine by causing the wheel
to evolve at a suitable rate by gearing in which case the cutter would have a
feeding movement in a circular path only.
For special purposes the end of the rocker may be formed into a circular rack

page_text: with suitably geared pinion to give horizontal or endwise feed
The woim wheel
or worm for circular feed may be replaced by a rack and wheel or either or both
feed geais may be replaced by templates giving any motion desued.
In dealing with surfaces where the vertical motion 18 not cucular the table
cariying the piece acted on 15 moved upwards and downwards by suitable
genring.
When dealing with a cylinder the axis of which is parallel with the axis of the
1ocker the cylinder is given an angular motion by suitable gearing and the slide 15
geared to give the necessary horizontal feed
Dated this 27th day of December 1894.
Improvements in Apparatus for Outting Teeth in Worm Wheels, and
for Milling Out Helical or other Grooves or Slots.
I, WILLIAM MORISON, Manager, Engine Department, of The London &
Glasgow Engineering and Shipbuilding Company, (Limited), 172 Laucefield
Street, in the City of Glasgow, 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 provide a machine for accurately and
inexpensively milling out or sumilarly cutting the teeth of worm wheels of any size
and pitch, the improved apparatus being also applicable for milling out helical or
other grooves or slots in flat, concave or convex surfaces.
The invention 18 illustrated by the accompanying diawings, Fig. 1 being a
longitudinal elevation, Fig. 2 an end elevation and Fig 3 a plan of the improved
machine, while Fig. 4 is a detail view of the cutter operating on a worm wheel.
Under the invention, as shewn particularly at Fig. 3 the teeth of a worm
wheel A are cut by preference singly, but it may be several at a time, by means of
a suitably shaped rotating milling cutter B carried on a crauk like rocking frame
or bar C which has imparted to it a motion of partial rotation combined with an
end wise movement serving to traverse the cutter B through a path corresponding
to the space to be formed between the teeth of the wheel, the spaces being thus cut
so as to leave the teeth intact on the wheel rim
The rocker bar C is carried in bearings D upon a stationary framing, or it
might be on a single or compound slide, and the bai C is caused to turn on its
axis E by means of a woim wheel F on it in gear with a rotating worm G this
movement being designed to travoise the inilling cutter B through an aic corre-
ponding to the concave face of the wheel A and the radius of which may bo varied,
being dependent ou the distance of the cutter face from the axis of the rocker bar,
while the circular traveise may extend through about 270 degrees when required.
The horizontal or endwise traverse or feed of the rocker bar C and the milling
cutter B carried by it, may be imparted by a screw II fitted on the end E of the
rocker and working in a nut I fixed in a bracket on the slide or main flaming the
pitch of the screw II being the same as that of the worm with which the wheel
being cut is intended to gear, or the feeding movement may be imparted by other
suitable gear. The milling cutter B which is preferably of the shape in contour
collesponding with the space to be cut between the teeth, .e. the thread of the
worn, is carried on a spindle J fitted in the locker C and driven by a pair of mitre
bevel wheels K, L, carried in a bracket M formed or fixed on the rocker C, the

page_text: bevol wheel L being fixed on an intermediate shaft N supported on bearings ✪ m
the bracket M and in a bracket Q keyed on the rocker shaft E. The intermediate
shaft N is driven by spur gearing R, S, from a shaft T in hoe with the axis E of
the rocker C so that the driven wheel S moves around the driver R.
The worm wher) A in which the teeth are to be cut is inouuted on a spindlo U
furnished with dividing mechanism such as 18 used in cutting ordinary toothed
wheels, the wheel A being held stationary while the tooth is cut and moved round
for the succeeding cut, whilst the cutter B 18 outwith the wheel.
When the framing or bracket D carrying the rocker bar C and gear is carried
on a slide a feed gear may be applied to the latter to impart the endwise feeding
movement to the locker C and its cutter B.
The teeth in worm wheels may also be cut by this machine by causing the wheel
to revolve at a suitable rate by gearing in which case the cutter B would have a
feeding movement in a circular path only.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what mannei the same is to be performed, I declare that what I
claim 18:-
1. The combination of parts constituting the improved machine for cutting teeth
in worm wheels or for milling out helical or other grooves or slots substantially as
described.
2. In a machine for milling out helical teeth or grooves the combination of the
cranked rocker bar Cand milling cutter B rotated by gearing carried on said bar
substantially as described.
3. In a machine for milling out helical teeth or grooves a rocking flame or cutter
carrying bar combined with means for imparting motion of partial rotation and
endwise movement thei oto substantially as described.
4. The combination with the crauked frame or cutter carrying bar C of the
worm wheel F thereon operated by a worm G for partially rotating the bar C and
the screw Hin a nut I adapted to traverse the bar longitudinally substantially as
descubed.
Dated the 27th day of September 1895.