IMPROVEMENTS IN LATHES FOR WOOD TURNING
Year: 1876

page_text: LETTERS PATENT to Edwin Silver, of Reading, in the County of Berks, Wood
Turner, for the Invention of " IMPROVEMENTS IN LATHES FOR WOOD TURNING."
PROVISIONAL SPECIFICATION left by the said Edwin Silver at the Office
of the Commissioners of Patents on the 26th October 1876.
EDWIN SILVER, of Reading, in the County of Berks, Wood Turner.
MENTS IN LATHES FOR WOOD TURNING."
" IMPROVE-
This Invention relates to a novel arrangement of lathe, by the use of which
boxes may be turned with great accuracy and rapidity from continuous lengths of
wood, all the movements required being automatic.
The lathe is provided with a hollow mandril, through which the lengths of wood
are fed to receive the action of the cutters.
The mandril is fitted with indenting blades, which enter the periphery of the
wood to take a hold thereon for the purpose of giving it rotary motion, the mandril
being driven by an overhead belt or its equivalent.
In rear of the headstock carrying the hollow mandril fixed knives are provided
for bringing the wood to shape and ensuring its entrance and passage through the
mandril.
In front of the mandril is a headstock mounted on a slide, and carrying a forked
cutter or a pair of cutters, which receive a rapid rotation in the opposite direction
to that of the wood, and are intended to operate simultaneously, hollowing out the
box, and bringing its periphery to shape. So soon as the wood is fed forward these
cutters advance, and coming upon the rapidly rotating wood in the direction of its
length shape it externally and internally. On the completion of this operation a
side cutter advances, which gauges the length of the box and at the same time
chamfers the bottom edge thereof.
The third cutter next advances from the opposite side to finish the edge of the
box, and by means of a fourth cutter the box is severed from the length of wood,
Some slight modification in this arrangement of the cutters may be desirable to suit
various kinds of work, but in all cases the cutters will be advanced and retracted
by a horizontal cam common to all the cutter slides. This cam is situate below
the bed of the lathe, its centre of motion being in advance of the hollow mandril,
and immediately below the work.
Dis Cli

page_text: The lathe bed is slotted radially from the centre of the cam to receive the cutter
slides, and pendant from those slides are bowles, which enter grooves in the upper
face of the cam. The under face of the cam is also grooved, and it gives a traverse
motion to the slide carrying the headstock, and also to the slide which carries the
wood.
The motion of the cam is transmitted to the slide of the headstock through link
rods connected with a rocking arm, which allows of the adjustment of the length of
traverse of the headstock to suit different kinds of work, and the motion of the cam
is transmitted to the feeding slide through a traversing bar which connects with a
travelling chain, the opposite ends of which are connected to the feeding slide.
In some cases I propose to hollow out the box by means of a rotating cutter set
excentrically to the wood, and for this purpose I provide a lateral adjustment for
the headstock. By setting this cutter a little out of centre, and proportionately
reducing the length of its cutting edge, I enable the cutter to work very efficiently
on hard woods, its operation being somewhat slower than when working con-
centrically.
It will be understood that the lids of boxes may be readily turned in this lathe,
the advance of the cutters being timed to suit the work.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edwin Silver in the Great Seal Patent Office on the 26th April
1877.
EDWIN SILVER, of Reading, in the County of Berks, Wood Turner.
MENTS IN LATHES FOR WOOD TURNING."
" IMPROVE-
This Invention relates to a novel arrangement of lathe, by the use of which boxes
and other articles may be turned with great accuracy and rapidity from continuous
lengths of wood, all the movements required being automatic.
The lathe is provided with a hollow mandril, through which the lengths of wood
are fed to receive the action of the cutters.
The mandril is fitted with indenting blades, which enter the periphery of the
wood to take a hold thereon, for the purpose of giving it rotary motion, the mandril
being driven by an overhead belt or its equivalent.
In rear of the headstock carrying the hollow mandril fixed knives are provided
for bringing the wood to shape, and ensuring its entrance into and passage through
the mandril.
In front of the mandril is a headstock mounted on a slide, and carrying a forked
cutter or a pair of cutters (when boxes are to be made) which receive a rapid
rotation in the opposite direction to that of the wood, and are intended to operate
simultaneously, hollowing out the box, and bringing its periphery to shape. So
soon as the wood is fed forward these cutters advance, and coming upon the rapidly
. rotating wood in the direction of its length shape it externally and internally. On
the completion of this operation a side cutter advances, which gauges the length of
the box, and at the same time chamfers the bottom edge thereof.
The third cutter next advances from the opposite side to finish the edge of the
box, and by means of a fourth cutter the box is severed from the length of wood.
Some slight modification in this arrangement of the cutters may be desirable to suit
various kinds of work, but in all cases the cutters will be advanced and retracted by
a horizontal cam common to all the cutter slides. This cam is situate below the
bed of the lathe, its centre of motion being in advance of the hollow mandril, and
immediately below the work.
The lathe bed is slotted radially from the centre of the cam to receive the cutter
slides, and pendent from those slides are bowles, which enter grooves in the upper
face of the cam. The under face of the cam is also grooved, and it gives a traverse

page_text: motion to the slide carrying the back headstock, and also to the slide which advances
the wood. The motion of the cam is transmitted to the slide of the back headstock
through link rods connected with a rocking arm, which allows of the adjustment of
the length of traverse of the headstock to suit different kinds of work, and the
motion of the cam is transmitted to the feeding slide through a traversing bar which
connects with a travelling chain, the opposite ends of which are connected to the
feeding slide.
In some cases I propose to hollow out the box by means of a rotating cutter set
excentrically to the wood, and for this purpose I provide a lateral adjustment for
the back headstock. By setting this cutter a little out of centre, and propor-
tionately reducing the length of its cutting edge, I enable the cutter to work very
efficiently on hard woods, its operation being somewhat slower than when working
concentrically.
In the accompanying Drawings I have shewn in several views my improved con-
struction of lathe.
Fig. 1 is a side elevation of the lathe; Fig. 2 is a plan view of the same; Fig. 3
is a cross section taken in the line 1, 2, of Fig. 1, looking in the direction of the
arrow; and Fig. 4 is an elevation of the feeding end of the lathe.
Fig. 5 is a partial plan view of the bed of the lathe, illustrating the relative
position and form of a set of cutters suitable for forming boxes; and Fig. 6 is a
side elevation of the same parts.
Fig. 7 is a plan view of the cam from which the back and forward motions of the
several slides are obtained; and Fig. 8 is a sectional plan view of a portion of the
bed surrounding the cam.
Fig. 9 shows in side clevation the arrangement of slide which carries the tools
for reducing the diameter of the wood that is to be formed into boxes; and Fig. 10
is an elevation of the slide which carries the knife for smoothing the periphery of
the box.
In Figures 1 and 2 A is the lathe bed, on which is mounted the hollow mandril B
which mandril forms at once a guide and a support for the length of wood under
operation, and imparts rotary motion thereto, it being driven by an overhead belt ;
C is the feeding slide, which carries the work, and advances it to the cutters; this
slide moves in V's on the lathe bed, and it receives its motion from a moveable
rack D, which slides in guides provided for it in the lathe bed, and having attached
to it an endless chain D¹. The feeding slide is fitted with pawles c, which drop
into the teeth of the rack D, but which are capable of being disengaged therefrom
by means of a slotted wedge piece, on the incline of which pins projecting from the
pawles c rest. This endless chain D' carries a slotted link d, to which an adjustable
lug d¹ is secured. This link d is formed with a fixed lug d², and through these lugs
passes the round end of a sliding bar E. This bar E is fitted with two collars or
stops e, c¹, which embrace the two lugs d, As therefore this bar E moves
endwise its stops will strike against one or other of the lugs of the link d, and
thereby give a traverse motion to the chain, and consequently to the rack D con-
nected therewith. When therefore the rack D moves in the direction of the arrow,
Fig. 1, the feeding slide will advance, the distance being determined not by the
traverse of the bar E, but by the position of the lug d' in relation to the stops on
the bar E.
In order to maintain the advance of the feeding slide pawles c* are provided,
which take into a fixed rack D* (see Fig. 1); this allows of the rack D (which for
this purpose is formed with ratchet teeth) sliding backwards to take up a fresh
position. The sliding bar E (see Fig. 8) extends to near the centre of the lathe,
and it is there connected to the slotted end of a bell-crank lever E', which is pivotted
to a bracket of the lathe bed. The opposite end of this bell-crank lever carries a
bowle, which enters a groove on the under side of the cam F, shewn by dots in
Fig. 7; the rotation therefore of this can imparts the feed motion to the work;
this cam F (see Fig. 1) is mounted on a vertical shaft F', and upon this shaft is keyed

page_text: a worm wheel F2, into which works a worm F³, keyed to the main driving shait F
which shaft receives motion from a belt passing over one or other of the pulleys F³.
The groove in the under side of the cam F, which receives the bowle of the crank
lever E¹, receives also the bowle of a sliding bar G', which is jointed to one end of
a link G2 that is connected adjustably to a rocking arm Gs; this arm is connected
by a second link G₁ to the slide of the back headstock G. The rotation therefore of
the cam F not only advances the work to the cutters, but also advances the cutters
carried by this headstock to the work so soon as the work has been brought up into
position.
By reference to Fig. 5 the form of cutters which are used on the back headstock
will be seen; g, gl, are two parallel blades turned at right angles at their extremities.
The shorter of these blades is intended to hollow out the box, and the longer one
to gauge its external diameter and turn it down roughly. For this purpose a rapid
rotary motion is given to the mandril carrying the cutters in the opposite direction
to the axial motion of the work.
As the depth of the boxes to be made on the lathe will vary provision is requisite
for adjusting the advance of these cutters to suit the work in hand, and it is for
this reason that the arrangement described for connecting the slide G with the
sliding bar G¹ is adopted. The slide G is also adjustable, relatively to the link G*,
to permit of its being set on the lathe bed to suit different lengths of work.
When the cutters g, g³, have performed their part of the work they retire to give
place to the next advancing cutters h, h¹, which are carried by a slide H. This
slide H is connected at its under side by a link H¹ to a bell-crank lever H² (see
Fig. 8), which bell-crank lever is pivotted to the lathe bed, and carries a bowle that
works in the outer groove 1 of the upper face of the cam F. As the cutters h, h¹,
advance the one forms the lip of the box by cutting a recess on the end of the work
and the other takes off the rough edge of the lip. As these cutters retire a cutter i
descends on to the work to finish the periphery of the box. This cutter is carried
by a slide I (see Fig. 1 and the detached view Fig. 10) which moves over ✓ guides
carried by a bracket piece B¹ forming part of the headstock B*; connected to this
slide I is a link ¹ which connects with a bell-crank lever pivotted to the side of
the headstock B*. The lower end of this bell-crank lever is jointed to a sliding
rod 3 (see Fig. 8) which works in guides provided for it in the lathe bed. A stud
projecting from this rod enters a slot in a crank lever I', which has its fulcrum
on the lathe bed and carries a bowle that enters the outer groove 1 in the upper
face of the cam F. By the rocking of this bell-crank lever I' the slide I is brought
gradually down, so that its tool i may act upon the work and finish the outer
periphery of the box. When this is effected the slide I will rise, and a rectangular
tool will next advance to trim the inner edge of the lip and smooth the end
surface thereof. This tool is carried by a slide K, from the outer side of which
projects a cranked pin for carrying the bowle that enters the groove in the upper
face of the cam F. The continued rotation, therefore, of this cam advances all the
slides that are in connection therewith in their due order. The tool holder k¹ of
this slide K is fixed to a vertical pin K2 by a clamping screw. This pin is free to
turn in the slide, and the tool holder is held in position by means of a spring K³,
which allows it to yield to the pressure of a fixed stop (not shown in the Drawing)
pressing against the lower cranked end of the pin K² as the slide is advanced
towards the work.
The object of giving a lateral tipping motion to the tool holder is to advance the
tool slightly within the box, and thus allow of its turning off the inner edge thereof
or chamfering the lip inwards, as shown at Fig. 5. As this tool retires the tool
advances to sever the finished box from the length of wood under operation. This
parting tool is carried by a slide L, which has a bowle on its under side that
enters the outer groove 1 in the upper face of the cam F, and by this means the
parting tool is advanced and retired in its proper order.
Before applying the wood to the feeding slide C it will be necessary to rough out

page_text: or shape the forward end thereof, in order that it may enter the hollow mandril B.
To effect this I provide on the lathe bed a sliding clamp M (shown detached at
Fig. 11) for holding the wood and presenting it to a rotating cutter. This cutter
I fix to a holder N, carried by the mandril of the back headstock G. By forcing
up the wood into contact with this cutter while the latter is receiving a rapid
rotary motion from an overhead belt, the end of the wood so presented will be
trimmed down roughly or so reduced as to permit of its entering the hollow
inandril B.
To provide for the passage of the wood through this mandril under pressure of
the advancing feeding slide C, the fixed cutters o are employed. These cutters are
carried by the holder O, (shown detached at Fig. 9,) which holder is pivotted to the
end of the headstock B*. For adjusting the cutter holder O to the desired angle
it is provided with a slotted segment piece, which permits of the clamping of the
holder to the headstock by a clamping screw. The cutters are also made adjustable
by means of a screw o¹.
In order to avoid the inconvenience and risk to the attendant in catching the
finished boxes as they are detached from the length of wood by the parting tool,
an automatic receiver is provided which advances to the work in time to receivo
the falling box and then moves back and discharges it from the machine. This
receiver consists of a cylinder P, open at both ends, and furnished at its under side
with a socket piece p to receive a horizontal pin projecting from a cranked arm p¹
made fast to a vertical spindle P¹. This spindle passes through and is supported
in a bearing formed on the lathe bed, and to its lower end (below the lathe bed)
a slotted link p² (see Fig. 8) is keyed. A pin on a horizontal slide P2 enters the
slot of this link for the purpose of communicating a swinging motion through the
spindle P¹ to the receiver P. The slide P2 is furnished on its under side with a
bowle, which enters the cam groove 2 of the cam F. As therefore this cam rotates
it will, in due course, move the receiver P up to the work to receive the detached
box and then move it back to the side of the lathe bed. This receiver is furnished
with a stop p³, which by bearing against the cranked arm P¹ retains it in a hori-
zontal position although counterweighted at its forward end.
In order to discharge the box from the receiver it is caused to tip on its support
when brought to the side of the lathe bed. This is effected by means of a pin,
which projects down from the socket p and strikes against a stop p¹, made fast to
the side of the lathe bed. When the receiver P is thus tipped the box will be
shot endwise into any suitable receptacle.
When manufacturing boxes, say of three and one-half inches in diameter, I prefer
to adjust the holder of the cutter g excentrically, and for this purpose I provide for
traversing the back headstock laterally, as shown at Fig. 1. The cutter g, when its
holder is set excentrically, will then act more slowly, but its cuts will be clean, and
the necessity for making it of a length equal to half the diameter of the box will be
avoided.
When working with an excentric cutter g the cutter g¹ must be removed from
the holder, and in lieu thereof the tool i will both rough out and finish the periphery
of the box.
It will be understood that the hollow mandril B should be made of a maximum
diameter, and when small sizes of boxes are required to be produced this mandril
will be fitted with a bush corresponding in diameter with the work in hand, so as
to form a suitable guide for the length of wood fed up to the cutting tool.
From the foregoing explanation it will be seen that the lids of boxes may be
readily turned in this lathe, the length of feed and the advance of the back bead-
stock being specially adjusted to suit the work.
Having now set forth the nature of my Invention of "Improvements in Lathes
for Wood Turning," and explained the manner of carrying the same into effect, I
wish it to be understood that under the above in part recited Letters Patent, I
claim the arrangement of mechanism for producing an intermittent feed and effecting

page_text: the advance and retirement of shaping cutters consecutively to and from the work,
as and for the purpose above described.
In witness whereof, I, the said Edwin Silver, have hereunto set my hand
and seal, the Twenty-sixth day of April, in the year of our Lord One
thousand eight hundred and seventy-seven.
E. SILVER. (L.S.)