Improvements in and relating to Pentagraph Tracing or Engraving Machines.
Year: 1888

page_text: Date of Application, 12th Sept., 1888
Complete Specification Left, Sth June, 1889-Accepted, 27th July, 1889
PROVISIONAL SPECIFICATION.
Improvements in and relating to Pentagraph Tracing or Engraving
Machines.
We, JOHN BRYCE, of 23 Bellgrove Street, Engraver, and ADAM KNOX, of 47
Crownpoint Road, Engineer, both in Glasgow, in the County of Lanark, do hereby
declare the nature of our Invention to be as follows :-
Our Invention has reference to the construction of pentagraph tracing or engraving
machines for the tracing or engraving of ornamental designs on the surfaces of gas
moons or globes, tumblers, glasses, vases, and other circular or cylindrical objects,
such as copper rollers, or conoidal or polygonal objects, whether made of glass,
metal, or other material, and comprises a novel arrangement and combination of
mechanism or mechanical motions to be applied to and actuated by the ordinary
mechanical pentagraphic motions of other tracing and engraving machines heretofore
in use.
A main improvement and departure of this invention from ordinary pentagraphic
tracing and engraving machines, consists in fixing and mounting the objects on a
stationary frame and brackets or arms, all nearly in axial line within a rotating open
cylinder or cage, with longitudinal vertical bars outside, on which the finger levers
of the tracing points or diamonds are secured in any desired number to suit the
design or number of patterns to be treated round the circular objects.
By these improvements a large number of objects can be operated on in the
machine at one time, while more claborate and superior designs and repeats of the
patterns can be traced or engraved on the objects in less time and at smaller cost
than has heretofore been done.
The nature and novelty of our invention consist all as follows:-The machino
consists as usual of two strong open side or end frames, strongly bound together by
suitable fixed stay cross bars or rails which make the whole a rigidly strong frame for
carrying all the working parts, free from vibration. The pentagraph mechanism of
the machine is of the ordinary flat table class, with the table secured rigidly and
horizontally in front of the two said frames and cross rails, for laying the paper with
the outlined design on, or the tracing or scored pattern plates at a convenient
height. for the operator tracing with. Över this table the hand arm, with its tracing
point, of the lower pentagraph horizontal traversing parallel acting bars or other
frame is made to traverse as usual by the proportional pentagraph frame traversing
as moved parallelly to and fro longitudinally on rollers on the table, and fixed planed
longitudinal and transverse traversing grooved or ribbed frames with antifriction
rollers between them, carried and secured on the said fixed side and transverse
frames or on the table; and from which ordinary pentagraph traversing compound
frame all the new mechanical motions are taken as will hereinafter be explained.
A long vertical traversing frame is mounted between the stationary end frames of
the machine, and behind the horizontal pentagraph mechanism, to reciprocate freely
up and down on antifriction wheels in guides when the horizontal traversing frame
is moved to-and-fro forward and backward from the vertical reciprocating frame.
Chains or bands would be attached to the upper parts of the traversing vertical
frame, passing over guide pulleys on the stationary side frames of the machine,
and would have weights attached to their lower free ends to rather more than
counter-balance the weight of the movable frame and all the cylindrical cages which
it carries with the tracing points or diamonds, or a counter-weighted lever or levers
may be employed instead of these chains and weights; and to the outer ends of this
lever or levers instead of the weight, a rod with a float or disc might be attached,
working in water or other fluid in a cistern close to the machine, any of which

page_text: would balance and steady this frame in its up and down reciprocations. A horizontal
spindle would be mounted laterally across the front of the machine above the
horizontal pentagraph traversing frames, its ends being carried in antifriction
rollers, centres, or bearings in the end frames of the machine. Pulleys or cones
would be mounted near the ends of this spindle, and steel bands would be turned
or coiled round these pulleys and have their ends attached to the top and bottom
respectively of the vertical movable frame; and have their other ends attached to
the forward and backward lower traversing parts of the pentagraph frame in such a
manner that when the pentagraph frame is drawn longitudinally towards the front
of the machine it pulls down the balance frame, and when pushed back from the
front of the machine it raises the frame or vice versa, or the weights might be made
to raise the frame in the upward direction. The balanced raising and lowering
vertical frame has one, two, or more of the open barred vertical cylinders or cages
mounted in antifriction centres or bearings in it, along the lateral length of the
machine, which move with and rotate or oscillate on their centres within the vertical
frame; and to the vertical bars, diamonds or points would be attached by light
spring clips, or levers, or other equivalent, the spring keeping each diamond lever
into action, to trace or engrave the design on the globes or objects, which would be
held vertically over each other, in brackets and gripping holders within the centre
of each rotating cage and attached to standards secured to the stationary framing of
the machine. The vertical motion of the balanced frame and cylinders or cages with
the diamonds or points produce the lines in the vertical direction on the objects ;
while the lines in the circular direction are produced by the rotation of the open
barred cylinders or cages with the diamonds or points secured on the vertical bars
of these cages. This circular or oscillatory motion of the cylinders or cages is given
as follows, by another vertical wheeled frame traversing horizontally and laterally
on guides within or on the horizontal bars of the vertical balanced frame carrying
the cylinders and cages so as to traverse with it vertically. To this horizontal
traversing frame is attached one or more bands by their ends, and passed round
pulleys or cones on each cylinder or cage, so that on this horizontal frame being
traversed in one direction, the one end of the bands turns the cylinders or cages
round in the corresponding direction, while the traversing of the horizontal frame
in the other direction causes the bands to turn the cylinders or cages in the
opposite direction, and thus the points or diamonds trace the circular lines in either
direction on the objects proportionate to the motions of tho pentagraph, this
horizontal moving frame being moved by the upper horizontal lateral traversing
frame of the pentagraph by an arm secured on it. working in a long vertical slot and
bar or guide of the horizontal frame.
The action of the mechanism would be as follows:-When the horizontal traversing
frame of the pentagraph is moved either laterally or longitudinally by moving the
hand tracing arm above the outlined. design or sprig on. the stationary, front table of
the machine, corresponding parallel motions would be transmitted to the oscillating.
cylinders or cages on the vertical movable frame, and the tracing diamonds or points
on the bars of this vertical cage would by these parallel notions trace or engrave
the design on the surface of the circular or cylindricall objects secured to the stationary
parts of the machine. Thus when the tracer arm of the pentagraph and horizontal
traversing frame are moved to the right or left laterally across the machine;, a corre
sponding circular motion would be transmitted to the rotating cylinders, or cages and
tracing or engraving points; and when the tracing arm and traversing. frame are
moved horizontally forward or backward; a raising and lowering parallel motion
would be given to the vertical balanced frame and cylinders or cages and a vertical
parallel motion would thus be transmitted to the diamonds or tracing points and
produce the vertical lines on the objects. The short levers. or arms for holding the
tracing or engraving diamonds or points, would be hinged or jointed at their inner
end to screw clamping or bracket parts for screwing to. the vertical bars or tubes of
the hollow open rotating cylinders or cages; so as to enable them; to be, swivelledi
and set to any angle tangentially to the surface of the parts of the particular, globulary

page_text: conical or circular work being engraved; and each rigid bar or tube carrying these
hinged arms with the diamonds, would be further fitted with an oscillating or
reciprocating vertical bar, carried on light bell-cranks, which when brought into
action in one direction would take all the tracing points and their levers out of
action on the article, by the raising and lowering of an upper and lower bow frame
carried on another set of bell-cranks fulcrumed on the upper and lower parts of the
raising and lowering frame, these bell-cranks being actuated to move the first bell-
cranks and vertical bars by a counter weighted treadle lever and the foot of the
attendant putting these lever arms and their points or diamonds all simultaneously
into action on the articles being engraved, the raising of the attendant's foot from off
the treadle, allowing its counterweight to move all the bell-cranks and take the diamond
or tracing points out of action, light springs being fitted on the bell-cranks to keep
the parts in their tracing position without friction of the bell-cranks acting on any
of the treadle mechanism for taking them out of action while the pentagraph machino
is at work. Each lever arm would also have a tempering screw for regulating the
pressure exerted by the india-rubber or other spring on the points or diamonds and
'surface of the articles being engraved.
For securing the globes or other circular objects to be engraved concentrically
within the cage, rigid lateral arms would project from a fixed slide guide vertical bar
of the frame, the outer end of each arm carrying a vertical centre stud in the axial
line of the eye with an arrangement of horizontal three or it might be four gripping
pawls or clips working in radial dovetailed slots or slides analogous to a differential
gripping chuck, the pawls being moved in their slide guides out and in by a loose
scroll grooved or equivalent disc mounted on the centre stud below the fixed gripping
chuck or pawls, a pin or stem on each pawl projecting down and working into the
scroll groove; all so that the turning of the scroll disc in one direction would traverse
the clips equally and radially inwards to grip the base of the globes concentrically
on the chuck, in the centre of the vertical cage, and vice versa turning the scroll disc
in the opposite direction would loosen them for the insertion of new globes.
Although this machine in its more full and complete construction as described, is
mainly designed for engraving glasses and other irregular circular work, acting on
the objects secured in a fixed frame, it is to be understood that it might also traco
or engrave patterns on copper rollers and operate two at a time or it might engrave
polygonal or flat objects secured on a suitable fixed part of the frame, and secure
the rotating cages with the diamonds from turning, allowing them to traverse only
with their lateral traversing frame, and trace or engrave only the horizontal lines
with the diamonds only acting on the flat surfaces to be engraved, turning the objects
intermittently with the flat sides towards the diamonds as each side or opposite sides
were engraved; or the flat plates might be secured on the inner horizontal traver-
sing frame in front of and so that a stationary bar or bars with the diamonds and
their clips secured on them might trace the patterns on its surface.
W. R. M. THOMSON & Co.,
Agents.
COMPLETE SPECIFICATION.
Improvements in and relating to Pentagraph Tracing or Engraving
Machines.
We, JOHN BRYCE of 23 Bellgrove Street, Engraver, and ADAM KNOX of 47 Crown-
point Road, Engineer, both in Glasgow, in the County of Lanark, do hereby declare
the nature of our said invention and in what manner the same is to be,performed,
to be particularly described and ascertained in and by the following statement in
writing, reference being had to the accompanying two Sheets of Drawings, and to
the letters and figures marked thereon, that is to say :-
Our Invention has reference to the construction of pentagraph tracing or engraving
machines for the tracing or engraving of ornamental designs on the surfaces of gas

page_text: moons or globes, tumblers, glasses, vases, and other circular or cylindrical objects,
such as copper rollers, or conoidal or polygonal objects, whether made of glass, metal
or other material, and comprises a novel arrangement and combination of mechanism
or mechanical motions to be applied to and actuated by the ordinary mechanical
pentagraphic motions of other tracing and engraving machines heretofore in use.
A main improvement and departure of this invention from ordinary pentagraphic
tracing and engraving machines, consists in fixing and mounting the objects on a
stationary frame and brackets or arms, all ready in axial line when round or
cylindrical objects are used, within a rotating open cylinder or cage, with longitudinal
vertical bars outside, on which the finger levers of the tracing points or diamonds
are secured in any desired number to suit the design or number of patterns to be
treated round the circular objects.
By these improvements a large number of objects can be operated on in the machine
at one time, while more elaborate and superior designs and repeats of the patterns
can be traced or engraved on the objects in less time and at smaller cost than has
heretofore been done.
And in order that our said invention, and the manner of performing or carrying
the same into effect or practice may be properly. understood, we have hereunto
appended two explanatory Sheets of Drawings, in which the same reference letters
are used to indicate corresponding parts in all the Figures where shown. Figure 1
on Sheet 1 is a back end elevation of a pentagraph tracing or engraving machine as
fitted with our improvements showing the fixed frame A to A and F, F, carrying
the objects Z and the balanced raising and lowering frame C to C, and lateral
traversing frame E to E, with the rotating cylinders or cages D to D², carrying
the diamonds or tracing points e.
---
Figure is a side sectional elevation as taken at right angles to, and near the
vertical line 1 1 of Figure 1. Figure 3 on Sheet 2 is a plan view corresponding
to Figures 1 and 2 on Sheet 1, and as taken on the line 22 of these Figures.
Figure is an enlarged back sectional elevation broken away corresponding to
Figure 1, to show particularly the mode of securing the clips and levers e to e³, carrying
the diamonds or points e to the vertical rotating cage bars D D'; and Figure 5 is an
edge view showing this, at right angles to the position shown in Figure 4. Figure 6
is a sectional elevation and a plan respectively of the disc plate or chuck to ƒ³
on which the circular objects Z are secured and carried. Figure 7 is a detailed
elevation of part of the machine as looking from the front; and Figure 8 a corre-
sponding side sectional elevation, as modified to suit for engraving flat objects.
Referring to these Drawings, the nature and novelty of our invention consists all
as follows: The machine consists as usual of two strong stationary open side or
end frames A, A, strongly bound together by suitable fixed stay cross bars or
rails A¹, A", A, which make the whole a rigidly strong frame for carrying all
the working parts, free from vibration, and secured by broad flanged feet to the
floor or other foundation at z. The pentagraph mechanism of the machine is of the
ordinary flat table class, with the table B B¹, secured rigidly and horizontally in
front of the two said frames A, A, and cross rails A' A" A for laying the paper
with the outlined design on, or the tracing or the engraved or scored pattern plates
at a convenient height for the operator tracing with and guiding the point a of the
pentagraph a to a'. Over the part B of the table B B, the hand arm a¹ with its
tracing point a of the lower pentagraph horizontal traversing parallel acting
bars a a² and a³, a, or other equivalent frame, is made to traverse as usual on the
fixed centre bracket a³, secured to the part B of the stationary frame or table B by the
action of this proportional pentagraph frane a¹ to a* to traverse the frame b laterally
on the lower frame 61 by the action of the moving arm centre bracket a secured to
this upper frame b which also by its roller pulleys 6" and rails 611 traverses the
frame below it longitudinally to-and-fro from front to back, and vice versa, on
pulleys and rails between them on the table part B¹, so as to actuate or traverse
the engraving or tracing points e, all as will hereinafter be described. The lower
frame is thus moved parallelly to-and-fro longitudinally on the rollers b³ on the

page_text: rails
of the table part B¹ and from which ordinary pentagraph traversing compound
frame a to a and b to 3 all the new mechanical motions of the tracing points e
and machine are taken as will hereinafter be explained.
A long vertical frame C, C1, C1, preferably of a strong light construction of cast
iron with strong vertical side rails CC, and transverse upper and lower rails C, C", is
made to traverse on plain guides c and pulleys at c near the upper and lower parts
of the side rails CC, the pulleys c¹ being carried in adjustable screw brackets c³
secured to the upper and lower parts of the main stationary frames A A. This
frame C, C, C, is thus mounted and guided between the stationary end frames A. A,
of the machine, and behind the transverse and longitudinal horizontal traversing
frames 6 to 6 of the pentagraph mechanism to reciprocate freely up and down on the
antifriction wheels c' on the guides c when the horizontal traversing frame b¹ is moved
to-and-fro forward and backward from the vertical reciprocating frame C C₁ C".
This vertical reciprocating frame C, C, C", is shown carried, preferably by a chain c³
attached by a stud at e to the centre of the top rail C', passed over the segmental end
of the longer arm of a lever (20³, fulcrumed on a steelyard bearing at C, on the
top of one of the side frames A, and has a chain C, passing down over the short
segmental arm (3, of this lever C2, C3, mounted with a rod and weights C³, C,
to
counterbalance or rather more than counterbalance the weight of the
frame C, C, C, and the transverse traversing frame E, E¹, E", carried on it, and all
the cylindrical rotating cages D to D³ and tracing points or diamond mechanisni
carried on these frames. Instead of a lever, C2, C3, and weights C, chains or bands may
be attached to the upper parts of the traversing vertical frame C, C, C, passing over
guide pulleys on the stationary side frames A¹ A, of the machine, and have
counter-weights attached to their lower free ends, to balance the weight of the
frame C, C, Con A horizontal spindle dis mounted laterally across the front of
the machine above the horizontal pentagraph traversing frames b. b₁, its ends being
carried in adjustable centre screw pins d¹ carried in brackets d" attached to the fixed
frame A A, of the machine, or it might be in antifriction roller bearings in the end
frames of the machine. Stepped pulleys or cones d² are mounted near the ends of
this spindle d, and steel bands d³, d, are turned or coiled round these pulleys d² and
have their one ends attached to the top and bottom at 1, respectively of the
vertical movable frame C, C, C; and have their other ends attached to adjustable
screw brackets at d d on the forward and backward ends of the longitudinal
pentagraph traversing frame bb' in such a manner that when the pentagraph frame
is drawn longitudinally towards the front of the machine it pulls down the balance
frame C, C, C, and when pushed back from the front of the machine it raises this
frame, or it might be vice versa; or the weights might be made to assist the raising
of the frame in the upward direction. The balanced raising and lowering vertical
frames C, C, C", carry one, two, or more open barred vertical cylinders or cages D
to D, with end driving cones D mounted in antifriction adjustable screw centres or
bearings at C in them, secured to the upper and lower rails C, C, along the
lateral width of the machine or frame, which move vertically with and rotate or
oscillate on these centres C on the cone pulleys D, D, of the frame D to D³,
within the vertical frame C, C¹, ". The vertical bars or tubes D¹ are secured at
their upper ends by brackets D¹ to the upper driving band cone D, and at their
lower ends by a transverse frame D2 carrying the lower driving band cone D. To
these vertical bars D' of the frame D to D, diamonds or points e are mounted by light
spring bell-crank levers e¹ and securing clip brackets ell, e³, mounted on ring
frames es, es, actuated by the turning of the frame D to D2, as hereinafter described,
the springs g³, of the levers e¹ keeping each diamond or tracing point e into action to
trace or engrave the design on the globes or objects Z, indicated by sharp lines in
Figures 1 and 2 and by dotted lines in Figure 4 and which are held vertically and
stationary over each other in fixed brackets F by gripping chuck holders f to f³, one
form of which is shown in section and plan in Figure 6, carried on a centre screw
securing spindle f one for each object Z to be engraved within the centre of each
rotating cage D to D', and attached by the adjustable brackets F to a main standard Fl

page_text: ་
e¹
'
at the back of the stationary framing of the machine, preferably with T slotted
vertical guides F" for securing the brackets F, by screws in these slots at any desired
height within the cages D to D2, as will hereinafter be described. The vertical
motion of the balanced frame C, C, C, and cylinders or cages D to D2, with the
diamonds or points e, produce the lines in the vertical direction on the objects Z;
while the lines in the circular direction are produced by the rotation of the open
barred cylinders or cages D to D2, with the diamonds or points and their levers e,
secured on the vertical bars D¹ of these cages D to D². This circular or oscillatory
motion of the cylinders or cages D to D is given as follows, by another vertical
wheeled frame E, E', E", with one central feather rail E, and an upper and a lower
transverse rail E¹, E", traversing by rollers E2 on the two latter horizontally and
laterally on guides at E within or on the horizontal bars C, C", of the vertical
balanced frame C to C carrying the cylinders and cages D to D³, so as to traverse
with it vertically. To this horizontal traversing frame E, E, E is attached. one or
more bands E3 by their ends with tightening screws to brackets at E secured to the
upper and lower horizontal frames E', E", on each side of each end cone or pulley D
of the rotating cages D to D2, and round which cones, each band E³ is passed to turn
the cages D to D2, so that on this horizontal frame E to El being traversed in one
direction within the cages to C, the one end of the bands E³ turns the cylinders
or cages D to D* round in the corresponding direction, while the traversing of the
horizontal frame E to E" in the other direction causes the bands E3 to turn the cylinders
or cages to D2 in the opposite direction, and thus the points or diamonds e trace
the circular lines in either direction on the objects Z to the extent or size of the
motion of this frame D to D2, and proportionate to the motions given to it by the
pentagraph, this horizontal moving frame E to E" being moved, by the upper
horizontal lateral traversing frame b, b, of the pentagraph, by an arm E' secured
on it working in a long vertical slot E in the vertical frame E, of the
frame E to E.
The action so far of the mechanism is as follows:-When the horizontal traversing
frame b, b, or b¹, 61, of the pentagraph is moved laterally or longitudinally by moving
the hand tracing arm a, a, above the outlined design or sprig laid on the stationary
front table B of the machine, corresponding parallel oscillating or rotating motions
are transmitted to the cylinders or cages D to D2 carried on the vertical movable
frame C to C through the lateral motions of the frame E to E, and the tracing
diamonds or points e on the bars of these vertical cages D to D2 would by these
parallel motions trace or engrave the design on the surface of the circular or cylindrical
objects Z secured as hereinbefore described to the stationary frame of the machine.
Thus when the tracer arm a of the pentagraph and horizontal traversing frame b, b,
are moved to the right or left laterally across the machine, a corresponding circular
motion is transmitted to the rotating cylinders or cages D to D2 and tracing or
engraving points ; and when the tracing arm a and traversing frame b', b', of the
pentagraph are moved horizontally and longitudinally forward or backward, a raising
and lowering parallel motion is given to the vertical balanced frame C to C" and
cylinders or cages D to D2, and a vertical parallel motion is thus transmitted to the
diamonds or tracing points e and produce the vertical lines on the objects Z. The
short bell-crank levers or arms e¹ for holding each tracing or engraving diamond or
point e, are hinged or jointed at their inner lower ends to the adjusting screw clamping
or bracket parts e", e, the latter of which clamp is secured to the ring frame e bolted
by clamp brackets 'el to the rigid vertical bars D', D¹, at any height desired, of the
hollow open rotating cylinders or cages D to D2; so as to enable the levers E and
points e to be swivelled and set to any angle tangentially to the surface of the parts of
the particular globular, conical, or circular work being engraved, one lever el and
pointer e being used for each flower or repeat division of the pattern on the object
being engraved. Each rigid bar or tube D D of the frame D to D2, carrying these
bellcrank arms el with the diamonds e is further fitted with a vertical reciprocating
bar frame G, G¹, and bars G working and mounted parallel to the bars D' in guide
clamps G secured to these bars D'. The lower cross bar G¹ of each of these slightly

page_text: vertical reciprocating frames G, G¹, is pulled upwards by springs G secured at their
upper ends to the guide clamps Gu when the attendant puts his foot on a treadle
mechanism; and pulled downwards by the automatic action of the weighted
levers H to H', of the treadle mechanism as hereinafter described. An upper bow
or ring moving frame 9 is secured by the clamps gl to the vertical sliding bars G of
the frame G, G', so as to rise and fall with this frame by the action of the before
mentioned springs and treadle mechanism, and a light screw clip g is secured on
the ring just over the horizontal arm of each bellcrank e', so that the lower end of
each clip comes in contact with the horizontal arm when this frame is brought down
by the automatic working of the treadle mechanism against the power of the springs G
to take all the tracing points e of the vertical arms of the bellcranks e¹ out of action;
and a small indiarubber or other spring 3 is attached to the screw or other part of
the clip g, and to the horizontal arm of the lever e', the strength of which might
be regulated by a screw to keep the tracing points e of this lever in action, when the
attendant puts his foot on the tread board of the treadle mechanism, and allows the
springs G to draw up the frame G G₁, so that the stop arms of the clip 9' are
clear of the horizontal arm of the tracing bellerank lever e¹; and also allows the
bellerank lever et freedom to act so that the point e would trace over an irregular
surface object Z only with the slight pressure of the spring g³. The treadle mechanism
consists as follows:-A counter-weighted lever spindle H is mounted in bearing
brackets in the lower part of the side frames A A, below the table B with a tread
board H in front where the attendant sits, and counter-weighted levers H" behind,
which automatically raise the tread board H' when not pressed down by the foot of
the attendant. A vertical lever H2, is mounted at one end of the spindle H, connected
by a rod H³ and differential lever H to the vertical spindle I carried in brackets I'
secured to the back part of the side frames A A, so as to swivel it slightly, and also
a lever I¹¹ on it, carrying a long vertical stud 12. This stud 12 acts on a roller at 13
on one end of the reciprocating bar I carried on the lower ends of the vertical bell-
crank levers, fulcrumed on brackets (11 secured at to the vertical reciprocating
frame C to C. Thus it will be seen that the horizontal arm of these bellcranks i, i,
acts on the lower bar G¹ of the frame G G¹ to pull this frame G, G', down against
the power of the springs G automatically as before described and remove the tracing
points e from the object by the weighted levers H" of the treadle mechanism; while
the pressing down of the tread board H¹ raises these levers and allows the springs Gill,
to pull up the frame G G¹, and cause the tracing points c to act all as described.
11
Referring to Figures 4 and 6-For securing each globe or other circular objects Z
to be engraved concentrically and stationary within the, cages D to D the rigid
lateral arms F project from a fixed slide guide vertical bar F F secured to the
centre of the upper and lower transverse rails A₁ A", of the main frame A A, at the
back as seen in Figure 1. The outer end of each arin F carries on a vertical centre
stud in the axial line of the eye of the chuck, f2, an arrangement of three or it
might be four horizontal slide gripping pawls or clips working in radial dove-
tailed slots or slide arms analogous to a differential gripping chuck, the pawls f
being moved in their slide guide stationary arms out and in by a loose scroll
grooved or equivalent disc f mounted on the centre stud below the fixed gripping
chuck and pawls f, ", a pin or stem on each pawl f" projecting down and working
into the scroll groove f³ in the loose disc f; all so that the turaing of the scroll
disc in one direction traverses the clips f, equally and radially inwards to grip
the base of the globes Z concentrically on the chuck, in the centre of the vertical
cage D to D³, and vice versa turning the scroll disc fin the opposite direction loosens
them for the insertion of new globes.
Although this machine in its more full and complete construction as described, is
mainly designed for engraving glasses and other irregular circular work, or objects Z
secured on separate chucks to f³, and arms F on a fixed frame F1, it is to be under-
5 stood that,, it might also trace or engrave patterns on copper rollers, or long
cylindrical objects one secured stationary in like manner within each frame D to
D² on the fixed frame F, F¹, without chucks ƒ, to, ƒ³.

page_text: Referring to Figures 7 and 8 on Sheet 2, this shows an arrangement suitable for
making the same machine trace or engrave flat surfaces, or polygonal objects with
flat surfaces, secured on a suitable fixed part of the frame indicated by dotted lines Z
in these Figures. The. objects Z would be secured by adjustable shifting screw
clips F secured to horizontal.hars F screwed or otherwise adjustably fixed to the
stationary vertical back frame F' secured to the upper and lower transverse stays A¹A",
of the main framing A to A, to suit the size of objects to be clamped. In this
case it is preferred to remove the oscillating or rotating frames or cages D to D²,
from the machine, and fix the vertical bars D₁, DI, direct by brackets at D to the
lower and upper arms E¹, E", of the horizontal moving frame E, E', E", within the
frame C to C, and secure to these rods D¹, D¹, straight bars ex, instead of the ring
bars e described in the previous Figures, and carry on these, the tracing bell-
cranks e¹, e, in an equivalent manner to that described in reference to the former
Figures, so as to traverse laterally and act on the flat stationary surface Z with the
motion of the frame E to E instead of in a circular manner as before described; and
then mount a moving straight frame or bars gx on the reciprocating bars G, instead
of the ring g of the former Figures, to carry the stop clips and springs g², g³, at the
side of each tracing lever e, e', to act on the horizontal arm of these tracing levers,
to take these out of action or put them into action by the treadle mechanism H to H¹
and I to I, all substantially as described and lettered to correspond in reference to
the former Figures.
The extreme vertical motion of the frame C, C, C", is stopped in the upward and
downward directions respectively by the brackets A* A* secured over and under it to
one fixed side frame A of the machine; and the extreme transverse motion of the
frame E, E, E, is stopped by the ends of its moving frame b, b, coming against the
stops secured to the longitudinal frame traversing with and under this
frame ball as seen more particularly in Figures 1 and 2.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is :-
First. The construction or arrangement and combination of the parts, and mechanical
motions, of a pentagraph tracing or engraving machine for circular or curvilineal
work or objects, in which the objects are fixed on a stationary frame and operated
upon by the tracing points or diamonds mounted on cylinders or cages carried and
rotated in frames moved vertically and transversely by and proportional to the motion
of the ordinary pentagraph pointer and mechanism, substantially as and in the manner
and for the purposes herein described, in reference to and shown in the accompanying
Drawings.
Second. In a pentagraph tracing or engraving machine, the fixing or mounting of
the objects to be engraved on a stationary frame and brackets or arms, within rotating
open cylinders or cages having vertical and hoop bars outside on which the finger
levers of the tracing points or diamonds are secured to engrave the designs on the
objects placed on the frame within the cage, substantially as and in the manner and
for the purposes herein described, in reference to and shown in the accompanying
Drawings.
Third. In a pentagraph tracing or engraving machine, the construction and use of
à balanced raising and lowering vertical frame carrying one, two or more open barred
vertical oscillating or rotating cylinders or cages mounted in antifriction centres or
bearings in it, the vertical bars of the cages carrying spring clips or levers to which
the diamonds or tracing points are attached the frame and cages being actuated in
opposite directions by and proportional to the motion of the pentagraph pointer and
mechanism, substantially as and for the purposes herein described, in reference to and
shown in the accompanying Drawings.
Fourth. In a pentagraph tracing or engraving machine, the producing of the
engraved lines on the objects in the vertical direction by the vertical motion of
the balanced frame, cylinders, and diamonds, and the producing of the lines on the

page_text: objects in the circular direction by the rotating of the open barred cylinders and
diamonds both proportional to and by the motion of the pentagraph pointer and
mechanism, substantially as herein described, in reference to and shown in the
accompanying Drawings.
Fifth. In a pentagraph tracing or engraving machine, the giving of a circular or
rotating motion to the cylinders or cages carrying the tracing or engraving points or
diamonds by a vertical wheeled frame traversing horizontally and laterally on guides
within or on the horizontal bars of the vertical balanced frame carrying the cylinders
and cages so as to traverse with it vertically, and turn the cages by bands and
pulleys through the traversing motion of the horizontal frame, substantially as and
in the manner herein described, in reference to and shown in the accompanying
Drawings.
Sixth. In a pentagraph tracing or engraving machine, the mounting on the
rotating cage bars, of vertical shifting rings or bars for carrying the levers of the
tracing diamonds or points, and also for carrying the reciprocating frame for putting
the levers and their points into or out of action by a treadle or equivalent mechanism,
substantially as and in the manner herein described, in reference to and shown in the
accompanying drawings.
Seventh. In a pentagraph tracing or engraving machine, the securing of the objects
to be engraved concentrically within the rotating cages or cylinders, by a clutch with
rigid lateral arms, and gripping pawls or clips, and a scroll grooved disc, substantially
as and in the manner herein described, in reference to and shown in the accompanying
Drawings.
Eighth. In a pentagrap tracing or engraving machine, the tracing or engraving of
flat surfaces or objects, by securing them stationary on the fixed frame and parallel to
the vertical and transverse moving balanced frames, and carrying the levers with their
tracing or engraving points on adjustable lateral bars or arms on the lateral traversing
frame, so as to be moved in opposite directions vertically and horizontally with
these frames by and proportional to the motion of the pentagraph pointer and
mechanism, substantially as herein described, in reference to and shown in the
accompanying Drawings.
Dated this 8th day of June 1889.
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.