IMPROVEMENTS IN MACHINERY FOR CUTTING OR SHAPING THE TEETH OF BEVIL WHEELS
Year: 1878

page_text: LETTERS PATENT to William Walton Urquhart and Joseph Lindsay, both of
Dundee, in the County of Forfar, North Britain, Engineers, for the Invention
of "IMPROVEMENTS IN MACHINERY FOR CUTTING OR SHAPING THE TEETH
OF BEVIL WHEELS."
Sealed the 15th April 1879, and dated the 17th October 1878.
PROVISIONAL SPECIFICATION left by the said William Walton Urquhart
and Joseph Lindsay at the Office of the Commissioners of Patents on the 17th
October 1878.
WILLIAM WALTON URQUHART and JOSEPH LINDSAY, both of Dundee, in the
County of Forfar, North Britain, Engineers. "IMPROVEMENTS IN MACHINERY FOR
CUTTING OR SHAPING THE TEETH OF. BEVIL WHEELS."
This Invention has for its object to construct bevil wheel teeth cutting or shaping
machinery in an improved and simplified manner, and so as to be conveniently
adjustable for bevil wheels of different angles, including such as are nearly flat.
The improved machinery can operate on metal wheels, or on wheels or patterns
of wood or other materials. In one modification a fixed part of the framing carries
in bearings in the usual way a horizontal spindle or mandril, on which the wheel or
pattern is fixed whilst being operated on, this mandril being fitted with the usual
dividing or pitching mechanism. On a pedestal or frame there is adjustably fixed
a ball, which in the case of ordinary or regular bevil wheels is always set exactly in
a line forming the prolongation of the axis of the mandril carrying the wheel or
pattern, the ball being set nearer to or further from the wheel or pattern accordingly
as the cone of the bevil wheel is less or more acute. The cutter for shaping the
teeth is carried by a block fitted to reciprocate in guides upon a beam, which is
always parallel or nearly so to the cone of the bevil wheel, and this beam rests, or
partly rests, on the ball herein-before referred to, the part fitting on the ball being
a block which can be fixed to any required part of the beam. The inner end of
[Price 8d.1

page_text: the beam is fitted so as to be capable of a cross movement on a block which is
jointed to another block, and this latter block can be fixed at any required part of
a radial arm, which is mounted so as to be capable of angular movement on the
main spindle or mandril or concentrically therewith, and also of some movement
along the mandril. The radial arın and bean can thus turn together about the axis
of the main spindle or mandril. The beam is moved across the block, to which it
is fitted by a screw worked by means of a band wheel, or by means of automatic
feed gear, and this cross movement serves for feeeding in the tool as the shaping of
the side of a tooth progresses. The shape of the tooth is determined by a pattern
plate, which is adjustably fixed on the stationary framing in a position near the
inner end of the bean, and the beam has fixed on it a narrow edged projection or
feeler, which rests on the stationary pattern plate with the pressure of the unbalanced
weight of the beam and radial arm. The feeler and pattern plate are by preference
at right angles to each other, and the parts are adjusted so that when the beam is
at the middle of its cross movement the cutting point of the tool, the middle point
of the feeler, and the pitch point of the pattern plate will all be in a line passing
through the centre of the ball, and as the tool holder is guided on the beam so that
the cutting point reciprocates always in a line directed to the centre of the ball, it
follows that the proper converging form will be given to the sides of the teeth. The.
tool holder is made to reciprocate by a connecting rod from a crank on a short shaft
carried by the beam, and driven by means of a belt or otherwise.
The machinery may be modified by substituting any suitable known form of
universal joint or equivalent mounting for the ball and the block resting thereon.
The tool, instead of being a plain reciprocating cutter, may be a rotating tool having
a number of cutting points, such rotating tool being however still a reciprocating
The machine may also be modified by arranging the mandril for the wheel or
pattern in a vertical or inclined position, the positions of the other parts being
also correspondingly changed.
one.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Walton Urquhart and Joseph Lindsay in the Great Seal
Patent Office on the 16th April 1879.
"
WILLIAM WALTON URQUHART and JOSEPH LINDSAY, both of Dundee, in the
County of Forfar, North Britain, Engineers. IMPROVEMENTS IN MACHINERY FOR
CUTTING OR SHAPING THE TEETH OF BEVIL WHEELS."
Our said Invention has for its object to construct bevil wheel teeth cutting or
shaping machinery in an improved and simplified manner, and so as to be conve-
niently adjustable for bevil wheels of different angles, including such as are nearly
flat.
Our improved machinery can operate on metal wheels, or on wheels or patterns of
wood or other materials. In one modification a fixed part of the framing carries in
bearings in the usual way a horizontal spindle or mandril, on which the wheel or
pattern is fixed whilst being operated on, this mandril having in connection with it
the usual dividing or pitching mechanisni. On a pedestal or frame there is adjust-
ably fixed a centre ball, which in the case of ordinary or regular bevil wheels is
always set exactly in a line forming the prolongation of the axis of the mandril
carrying the wheel or pattern, the centre ball being set nearer to or further from the
wheel or pattern accordingly as the cone of the bevil wheel is less or more acute.
The cutting or shaping mechanism is carried by a beam, which rests or partly rests
on the centre ball, and which has its inner end connected to a radial arin mounted
so as to be capable of angular movement on the main spindle or mandril, or concen-
trically therewith, and also of some movement along the mandril. The beam and
radial arm can consequently move together about the axis of the mandril, the
continuation of which axis passes through the centre of the centre ball. The
cutting or shaping tool is carried by a block, which is made to reciprocate along the
beam, so that the cut always takes place in a line directed to the centre ball, and
feed mechanism shifts the beam gradually inwards relatively to the radial arm, so
that the successive cuts are convergent and give the proper convergent form to the
teeth. The shape or profile of the teeth is determined by a pattern plate, which is
adjustably fixed on the stationary framing, a narrow edged projection or feeler fixed
on the beam resting on the pattern or profile plate with the unbalanced weight of
the beam and radial arm, and causing the beam to follow the intended profile as the
feed gear moves it inwards, one side of a tooth being shaped at a time.
Our improved machinery may be modified by substituting any suitable known
form of universal joint or equivalent mounting for the centre ball arrangement.
The tool may be either a plain reciprocating cutter or a rotating tool armed with
several cutting points, but still reciprocating as a whole. The machine may also be
modified by arranging the mandril for the wheel or pattern in a vertical or inclined
position, the positions of the other parts being also correspondingly changed.
And in order that our said Invention and the manner of performing the same
may be properly understood, we hereunto append four Sheets of explanatory
Drawings to be herein-after referred to, and representing one modification of our
improved machinery. In these Drawings the same reference numerals are used to
mark the same or like parts wherever they are repeated.
Figure 1, on Sheet 1 of the accompanying Drawings, is a plan of the machine;
Figure 2, on Sheet 2, is a side elevation; and Figures 3 and 4, on the same Sheet,
are enlarged detail views. Figure 5, on Sheet 3, is an elevation of the side opposite
to that shown in Figure 2; and Figure 6, on Sheet 4, is an end elevation.
At the head of the machine (at the left-hand side, in Figures 1 and 2) there is
a stationary bed frame or bench 7, 8, carrying in bearings 9, 10, the spindle or
mandril 11, on which the bevil wheel or pattern 12 to be operated on is fixed.
The mandril 11 has, as usual, in connection with it gearing for dividing or pitching
off the teeth on the wheel or pattern, this gearing consisting, in the present case, of

page_text: a worm wheel 13 fixed on the outer end of the mandril 11, and gearing with a
worm 14 on a shaft 15, having fast on it a spur wheel 16 geared by an inter-
mediate spur wheel 17 to a spur wheel 18 fast on a shaft 19.
The shaft 19 passes
through the bench 8 to the other end thereof, where it has on it a disc 20 formed
with a notched rim, together with a hand lever 21, by means of which the shaft 19
is, after the shaping of the side of each tooth, turned to the extent necessary for
bringing the next tooth of the wheel or pattern 12 into position. The wheels of
the dividing gearing are, as usual, changeable to suit the various numbers of teeth
required.
In a position at right angles to the head frame 8, 9, there is a stationary
frame 22, formed with two parallel horizontal guide bars 23 to receive a bracket or
holder 24, in which there is fixed a spindle having a centre ball 25 formed on its
upper end, as shown in the enlarged sectional elevation, Figure 4, Sheet 2 (Figure
being a plan corresponding to Figure 4). The bracket 24 can be fixed by a screw,
bolt, or clamp at any part of the guide bars 23, and the frame 22 can be adjusted
upon base plates 26, so that the centre ball 25 may be always placed as accurately
as possible in the continuation of the axis or centre line of the mandril 11, the
distance of the centre ball 25 being determined by the angle of the cone of the
bevil wheel to be operated on in each case.
The cutter 27 for shaping the teeth is carried by a block 28 fitted to reciprocate
in guides upon a bean 29 which is always parallel or nearly so to the bevil of the
wheel or pattern 12, and this beam 29 rests or partly rests on the centre ball 25,
the part fitting on the ball being a block 30, which can be fixed to any required
part of the beam 29, and which has a movable cap or side piece 31 to allow of the
socket in the block 30 enclosing a little more than the half of the ball 25, and
thereby preventing accidental separation of the ball and block. The inner end of
the beam 29 is fitted so as to be capable of a cross movement on a block 32 which
is jointed to another block 33, and this latter block 33 can be fixed at any required
part of a radial arm 34, which is mounted so as to be capable of angular movement
on the main spindle or mandril 11. On the mandril 11 there is fitted a ring 35
which is capable of movement along the mandril, and which is formed with
trunnions 36 jointed to upper and lower projecting or forked parts of the radial
arm 34, which can thus move in any required direction so as to accomodate itself
to different positions of the beam 29. The beam 29 is moved across the block 32
to which it is fitted by a screw spindle 37 worked by means of a crank handle 38,
and also by automatic feed gear, the latter consisting of a ratchet wheel 39 and
pawl lever 40 with adjustable connection for a rod 41, which is made to reciprocate
by a cam 42 on a rotating shaft. This rotating shaft is carried by a bracket 44
fixed to the beam 29, and has on it fast and loose pulleys 45 for a driving belt, and
also a crank pin disc 46, from which a rod 47 imparts the requisite reciprocating
motion to the cutter block 28.
The profile or pattern plate 48, by which the shape of the teeth is determined, is
adjustably fixed on a slide 49 which can be adjusted along the head frame or
bench 8 by means of a screw spindle 50. This profile plate 48 projects up vertically
and is set at about a right angle to a line on the pitch cone of the wheel or
pattern 12, and the shape of its edge is made a projection of the intended shape of
the teeth as radiated from the centre ball 25. On this profile plate 48 there bears
a narrow-edged projection or feeler 51 which is fixed to the beam 29, the unbalanced
weight of the beam 29 and parts carried by or connected to it thus resting by
means of the feeler 51 on the profile plate 48, so that as the beam 29 is moved by
the feed screw 37 it follows the profile of the plate 48 and causes the tooth to be
shaped accordingly. The bearing edge of the feeler 51 is by preference at right
angles to the profile plate 48, and as in every position of the beam the cutter 27,
when properly adjusted, moves in a line directed to the centre of the ball 25, it
follows that the proper convergent form must be given to the wheel teeth.
cutter 27 and the feeler 51 should be adjusted relatively to the movement of the
eutter block 28 in its guides on the beam 29, so that the point of the cutter and
The

page_text: the bearing edge of the feeler are throughout the movement of the cutter block in
a line passing through the centre of the ball 25.
Having thus particularly described our said Invention and the manner of
performing the same, we have to state that we do not restrict ourselves to the
precise details herein described and delineated, but that what we believe to be
novel and original, and claim as the Invention secured to us by and in terms of the
herein-before in part recited Letters Patent is,
1. The arranging or combining together of the parts of machinery for cutting or
shaping the teeth of bevil wheels, substantially in the improved manner herein
described and delineated.
2. The combination of the centre ball (25), beam (29), and radial arm (34)
arranged substantially in the manner and for the purposes herein-before described.
3. The arrangement of the fixed profile or pattern plate (48) and feeler (51),
whereby the movement for giving the required profile to the teeth is imparted to
the beam and radial arm (29, 34,) in a manner to secure true convergency in the
cuts, substantially as herein-before described.
In witness whereof, we, the said William Walton Urquhart and Joseph
Lindsay, have hereunto set our hands and seals, this Fourteenth day of
April, in the year of our Lord One thousand eight hundred and seventy-
nine.
WM W. URQUHART. (L.S.)
JOSEPH LINDSAY. (L.S.)