Mechanical Movement for Transforming Rotary Motion into Recip- rocating Motion, especially Adapted as a Bed Motion for Printing Presses.
Year: 1896

page_text: Date of Application, 21st Dec., 1896
Complete Specification Left, 13th Sept., 1897-Accepted, 21st Mar., 1898
PROVISIONAL SPECIFICATION.
Mechanical Movement for Transforming Rotary Motion into Recip-
rocating Motion, especially Adapted as a Bed Motion for
Printing Presses.
I, GEORGE CROYDON MARKS, of 18, Southampton Buildings, Chancery Lane,
London, W.C., Consulting Engineer (a communication from The Campbell Print-
ing Press and Manufacturing Company, a Corporation organised under laws of
State of New York, of 1, Madison Avenue, New York City, New York, United
States of America), do hereby declare the nature of this invention to be as
follows:-
The aim of this invention is to provide a new and improved mechanical move-
ment for transforming rotary motion into rectilinearly reciprocating motion,
especially adapted as a bed motion for printing presses.
A printing press bed, to secure the best results, must be run preferably at an
even speed during the forward and return strokes, and must be gradually stopped
and started again in the reverse direction without jar or vibration.
There are many mechanisms well known for giving the bed or reciprocating
member its main or direct forward and backward movement, whether the same be
at an even speed or not, and my invention consists in the combination with a bed
driven in this manner of a peculiar reversing mechanism, which consists of racks,
preferably curved, attached to each end of the bed, and a pinion mounted on a
revolving part, which pinion is adapted to alternately engage said curved racks
to reverse the movement of the bed in either direction.
The revolving part on which this peculiar pinion is mounted, as hereinafter
described, may also constitute the main driving gear for giving the bed its main
forward and backward movements.
A suitable guiding mechanism is also preferably used to keep the reversing
pinion in mesh with the curved racks.
By this mechanism there will be a constant mesh between the driving mechanism
and the bed.
I preferably use for my main driving mechanism a gear rotating in one direction,
disposed between two racks attached to the moving member, and with which the
gear alternately engages, said gear being alternately raised and lowered for this
purpose, and thereby giving the main reciprocating movement to the moving
member.
The specific guiding mechanism that I use, preferably consists of a curved face
parallel to each curved rack, and a roller mounted concentrically therewith.
'Mounted concentrically with the reversing pinion is a third roller, which engages
one of said curved faces and rollers as the reversing pinion reverses the movement
of the bed.
It is to be understood that the invention is applicable to any form of printing

page_text: press, whether the same has one or more impression cylinders, and no matter how
the impression cylinder or cylinders act in relation to the bed, or how the recipro-
cating member is mounted to slide on the frames, the invention being a mechanism
for imparting a reciprocating movement to the bed.
Mechanical Movement for Transforming Rotary Motion into Recip-
rocating Motion, especially Adapted as a Bed Motion for
Printing Presses.
I, GEORGE CROYDON MARKS, of 18, Southampton Buildings, Chancery Lane,
London, W.C., Consulting Engineer (a communication from The Campbell Print-
ing Press and Manufacturing Company, a Corporation organised under laws of
State of New York, of 1, Madison Avenue, New York City, New York, United
States of America), 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:-
The aim of this invention is to improve the arrangement of parts in mechanical
movements, which are designed to transform rotary motion into rectilinearly
reciprocating motion, and to this end, the invention consists of the devices described
and claimed in this specification, and illustrated in the accompanying five sheets
of drawings, in which,
Fig., 1 is a sectional elevation on the line 1-1 of Fig. 3,
Fig. 2 is a view of one end of the framing secured to the under side of the
reciprocating member looking at the same, from the opposite side to which the same
is shown in Fig. 1,
Fig. 3 is a sectional plan view taken on line 3-3 of Fig. 1,.
Figs. 4 to 9 inclusive are diagrammatic views of the actuating mechanism showing
the positions that they assume in one complete forward and backward movement
of the reciprocating member, and
Fig. 10 is a sectional elevation of a modified form of the mechanism,
Fig. 11 is a detail plan view of the operating parts shown in Fig. 10 upon an
enlarged scale,
Fig. 12 is a side elevation of the parts shown in Fig. 11,
Fig. 13 is an end elevation of a detail, and
Figs. 14 and 15 illustrate modifications showing how the parts may be put
together in different ways.
This invention, generally speaking, consists in a peculiar mechanical movement that.
is adapted to transformi rotary movement into rectilinearly reciprocating motion, and
the same may be applied and. adapted to any use or location, where it is desired
to use this movement.
The invention, however, has been principally devised for use in connection with
the reciprocating beds of printing presses, and the invention will be further
described as applied and used in connection with a printing press.
A printing press bed, to secure the best results, must be run preferably at an
even speed during the forward and return strokes, and must be gradually stopped
and started again in the reverse direction, without jar or vibration.

page_text: There are many mechanisms well known for giving the bed or reciprocating
member its main or direct forward or backward movement, whether the same is
at an even speed or not, and the invention consists in the combination with a bed
driven in this manner, of a peculiar reversing mechanism, which consists of a rack
preferably curved attached to the bed, and a pinion mounted on a revolving crank,
which pinion is adapted to engage said curved rack to reverse the movement of
the bed.
Two curved racks are preferably used so that the same pinion can reverse the bed
in either direction. The revolving crank, in which this peculiar pinion is mounted,
as hereinafter described, may be, also, the main driving gear.
A suitable guiding mechanism may also be used, if so desired, to keep the revers-
ing pinion in mesh with the curved rack or racks.
By this mechanism, there will be a constant mesh between the driving mechanism
and the bed.
The main driving mechanism preferably consists of a gear rotating in one
direction disposed between two racks placed on opposite sides of the gear, and
attached to the moving member, and with which the gear alternately engages,
and thereby gives a reciprocating movement to the moving member.
Referring now to the first three sheets of drawings, and in detail 9 and 10
represent the usual side frames of a printing machine, and between these side
frames may be secured a box-beam or girder 11.
A reciprocating bed or member 12, which is arranged to coact with any of the
usual forms of impression cylinders, as 13, indicated in dotted lines, is mounted
on suitable guide-ways 14 formed on the frames of the machine, and the recipro-
cating member 12 may have suitable grooves 15 engaging these guides 14, it so
desired.
It is understood, of course, that the invention is applicable to any form of print-
ing press, whether the same has one or more impression cylinders, and no matter
how the impression cylinder or cylinders act in relation to the bed, and no matter
how the reciprocating member is mounted to slide on the frames, the invention
being a mechanism for imparting a reciprocating movement to the bed.
Secured to the under side of the reciprocating bed or member 12 is a depending
frame, which consists of the brackets 16 and 17, which are connected together by
the tie 18, and secured to the under side of the bed is a rack 19, and secured to the
tie 18 by means of bolts or screws 21, is the rack 20, these two racks 19 and 20,
facing each other, as shown.
Bolted to one side of the depending bracket 16, by means of screws 23, is a
curved piece 22, which has teeth 221, as shown; and bolted to the depending
bracket 17, by means of screws 25, is a similar curved piece 24, which has teeth 241:
Secured to the front side of the bracket 16, by means of screws 27, is a frame 26,
which carries a stud 28, on which stud is mounted a roller 29, and secured to the
bracket 17 by means of screws 31, is a frame 30, which carries a stud 32, on which
a roller 33 is mounted, these two construction on opposite sides of the reciprocating
member, being similar..
The bracket 16 has a nicely finished curved face 220, which is substantially
founded on a circle struck about the centre of the stud 28, and the bracket 17 has
a similar curved face 240, which is substantially formed on a circle struck about
the centre of the stud 32; and the curved racks 221 and 241 are made sub-
stantially concentric with the curved faces 220 and 240, for a purpose hereafter
noted...
Secured on the box-beam or girder 11 is the bracket 34, which carries the two
journal boxes 341 and 342.
Journalled in the bearing 342 and in a bearing 37 secured to the frame 10, is
a shaft 35, which may be the driving shaft of the machine, and which may carry
the tight and loose pulleys 38 and 39.
The shaft 35 carries at the inner end thereof a pinion 36, which engages a
gear 40, which gear 40 is adapted, by means hereafter described, to alternately

page_text: engage the racks 19 and 20, and impart the main reciprocation to the reciprocating
bed or member.
This gear 40 is mounted on a shaft 41, which shaft 41 is journalled in an
eccentric bushing 42, which eccentric bushing 42 is journalled in- the bearing 341
of the bracket 34.
This eccentric bushing has an extension 43, which carries a pin 44, and con-
nected to this pin 44 is a yoke 45, in which yoke is secured a stud 4 carrying a
roller 47, and a stud 48 carrying a roller 49, and the yoke has a slot, engaging
which is a block 51 secured on a shaft 50, which shaft 50 is journalled in the
frames 9 and 10, as shown.
Secured on the shaft 50 is a cam 52 which is adapted to reciprocate the yoke 45.
The shaft 50 is preferably driven by means of gear 53 secured on the same, which
gear 53 is driven from the pinion 54 secured upon the shaft 35, as shown.
The cam 52 has two surfaces, a high surface 55, and a low surface 56, and these
two surfaces are connected by easy inclines 57.
As shown, the machine is designed to have what is known as a three revolution
driving gear; that is, the gear 40, which is the driving gear, makes one complete
revolution to give the bed its forward movement, and a half revolution to reverse
the movement of the bed in either direction. Then, if the reduction between the
gears 36 and 40 is two to one, the shaft 35 will make six revolutions for each com-
plete forward and backward movement of the bed.
As the cam 52 must make one complete revolution for each forward and back-
ward reciprocation of the bed in the specific device shown, the reduction between
the gear 53 and pinion 54 must be six to one.
The cam is so proportioned and designed, that the gear 40 will be held in engage-
ment with one rack as 20 during one movement of the bed, and while the reversing
mechanism is actuating, the cam will actuate the gear so that when the bed is
given by the reversing mechanism, back to the driving gear, the driving gear will
engage the other rack and make a complete revolution in engagement with the
same.
Of course, it is understood, that the invention is not limited to the proportion of
gearing herein described, as the same may be varied by the designer, and the
relative proportion and speed of the parts altered, as desired, for any location.
Secured to the side of the gear 40 by means of screws 59, is a pinion 58, which
is termed the reversing pinion.
This pinion, as shown, is made a trifle larger than one-half of the driving gear 40,
and the periphery of the reversing pinion is preferably set flush with the periphery
of the driving gear 40, as shown."
In the centre of this reversing pinion 58 is secured a stud 60, on which stud 60
is mounted a roller 61, which roller 61 is adapted to fit between the roller 29 and
the curved surface 220, or between the roller 33 and the curved surface 240.
The operation of the improved movement will now be described, and reference
to follow this description should be had to the diagrams shown in the third sheet
of drawings.
In Fig. 4, the bed is shown as just completing its main movement to the left,
and the driving gear 40 as just leaving the rack 20 the roller 61 as coming in
between the curved face 240, and the roller 33, and the reversing pinion 58 as
engaging the curved rack 241.
Now, during the next quarter revolution of the driving gear 40, the bed will be
moved a distance still further to the left by the action of the revolving reversing
pinion 58 working in the curved rack 241, which distance will be substantially
equal to the diameter of the reversing pinion 58, which is apparent, if it is noted
that the radius of the semi-circular rack 241 substantially is equal to the diameter
of the pinion 58, and hence must be moved when operated on by pinion 58, the
amount of its radius.
As the reversing pinion 58 runs up the curved rack 241, the roller 61, acting on

page_text: the roller 33, will properly guide the reversing pinion with the rack, and keep the
same, at all times, in proper mesh.
This movement will commence at the same speed at which the bed is moved by
the main driving mechanism, and will gradually decrease to zero, and will bring
the bed to a stand-still at its left hand position, or with the parts in the relative
positions shown in Fig. 5.
Now, during the next quarter revolution of the driving gear 40, the reversing
pinion 58 will run up the upper portion of the curved rack 241, and will move
the bed towards the right, a distance equal to the pitch radius of the curved
rack 241, or the pitch diameter of the pinion 58, at a speed gradually accelerating
from zero to the pitch peripheral speed of the driving gear 40, and will bring the
parts to the position shown in Fig. 6.
In the last half revolution of the gear 40, the gear 40 will have been raised by
the mechanism before described, so that the gear 40 will now be in its upper
position, and the same will nicely engage and come into the rack 19.
Now, during the next complete revolution of the gear 40, the bed will be moved
to the right a distance equal to the pitch circumference of said gear 40, at an even
speed, and the parts will be brought to the position shown in Fig. 7.
Now, during the next quarter revolution of the gear 40, the reversing pinion 58
will work with the curved rack 221, and will move the bed to the right a distance
equal to the pitch radius of the curved rack 221 or the pitch diameter of the
pinion 58, at a speed commencing at the same speed at which the bed is moved by
the driving gear, and gradually decreasing to zero, when the bed will be brought
to a stand-still at its right hand position, and the parts brought to the position
shown in Fig. 8.
Now, during the next quarter revolution of the gear 40, the bed will be started
on its movement to the left, at a speed gradually increasing from zero to the main
driving speed, a distance equal to the pitch radius of the curved rack 221 or the
pitch diameter of the pinion 58, and the bed will be started nicely on its move-
ment to the left.
During this last half revolution of the driving gear 40, the same will have been
dropped or lowered by the mechanism before described, so that the same can now
nicely engage the end of the rack 20, as shown in Fig. 9.
Then, during the next complete revolution of the gear 40, the bed will be moved
to the left a distance equal to a pitch circumference of said gear 40 at an even
speed, and the parts will be brought back to the position shown in Fig. 4, and a
complete cycle will have been described.
Thus the complete movement of the bed in either direction is a pitch circum-
ference of the driving gear 40 plus two pitch diameters of the reversing pinion 58,
and the main driving gear 40 will make three complete revolutions for each com-
plete forward and backward reciprocation of the bed.
It
As before stated, this proportion between the parts can be varied as desired.
will be seen that, as the reversing pinion engages the curved racks at the ends of
the bed to reverse the movement in either direction, the main driving gear will
clear the racks 19 and 20.
It will, also, be seen that as the reversing pinion engages these curved racks,
the rollers 61, engaging the roller 33 and the curved face 240, or the roller 29 and
the curved face 220, as the case may be, will accurately keep the reversing pinion in
mesh with the curved rack.
Although it might be practicable to use the reversing mechanism without this
guiding mechanism, still in most cases, the same is added to the reversing
mechanism.
The curved racks and the curved faces are eased or filed slightly, in the specific
design shown, so as to accommodate the slight rising and falling movement of the
reversing pinion 58 as the same moves up and down with the gear 40, as the gear 40
is raised and lowered from one rack to the other.

page_text: It is evident, of course, that the reversing pinion could be mounted on a crank
independent of the gear 40, if so desired, and work in the same manner.
The reversing pinion 58 is made substantially one-half the size of the gear 40,
and is set so that the centre of rotation of these two parts comes substantially on
the pitch circle of said pinion..
By this arrangement, it will be seen that a certain portion of the pinion, viz.
that nearest the centre of rotation is substantially at rest.
This gives in effect substantially a crank movement.
In actual practice, the reversing pinion is made slightly larger than one-half of
the gear 40, and this, in the particular arrangement is due to the fact that the
gear 40 is raised and lowered..
The curved racks are preferably made semi-circular, and of a diameter sub-
stantially equal to the distance between the racks 19 and 20.
It also will be seen that all the teeth of the pinion will engage with one curved
rack in one reversal. Hence, the part 58 is made a circular toothed pinion.
This gives a continuous mesh either between the rack and pinion mechanism
giving the bed its main reciprocation or between said reversing pinion and one of
the curved racks:
It will be noted that the reversing pinion and the curved racks are all dispos-d
to one side of the main driving gear, whereby, but a similar adjustment is necessary
.at each end of the bed, and whereby the gearing is arranged very simply and
efficiently.
The advantages of the device are apparent. The bed is moved preferably at an
even speed during its main forward and backward' movement, and is easily reverse 1,
being gradually retarded from its full speed to a state of rest, and gradually
accelerated and brought back to full speed in the other direction without jar or
vibration.
One important advantage in use with the device is that there is always a con-
stant gearing between the driving mechanism and the bed, no matter whether the
main driving mechanism or the reversing mechanism is in operation.
As has been before indicated, any other form of main driving mechanism, such
as any of the ordinary rack and pinion mechanisms could be used for giving the
bed its main reciprocation, the gear 40, in that event, becoming simply a crank
for carrying the reversing pinion, and it is immaterial whether or not this main
driving mechanism imparts an even or an uneven speed to the bed, during its
main or direct movement, the invention embracing the combination with any main
driving mechanism for the bed of the peculiar reversing mechanism.
In Figs. 10 to 12 a modified construction of mechanical movement is shown.
The differences shown in this construction are as follows:
1
The bed 12 has bearings 15 which engage grooves 14 on the side frames.
The connecting piece 18 of the previous device is omitted, and the lower rack 20
is secured by means of screws or bolts 21 directly to the brackets 16 and 17.
The curved racks 221 and 241 are cut directly on the brackets 16 and 17.
The studs 28 and 32 secured in the frames 26 and 30 have rollers 33 inade
integrally therewith, as illustrated in Fig. 11, and the studs are fitted to turn in
the frames and held in place by means of collars 320 and pins 321.
The screws 170 which are used to hold the brackets 16 and 17 to the bed 12 are
made very strong and heavy.
The stud 60 which is secured in the main driving gear 40 as a large circular
working shoulder 610 formed thereon, through which the screws 59, which hold
the reversing pinion 58 in place, pass.
The brackets 16 and 17 have large working faces 620 concentric with the curved
racks, and of a diameter substantially equal to the pitch diameter of the said
circular racks. The diameter of the circular working shoulder 610 is. substantially
equal to the pitch diameter of the reversing pinion 58.
The end of the stud 60 is a-t to engage the rollers 33.
The reversing movement is accomplished by the circular working shoulder 610

page_text: running around the working shoulder: 620; and by the reversing pinion: 58 engaging
one of the circular racks, the roller 33 engaging the stud 60 keeping the reversing
pinion in constant mesh during the reversing movement.
By this construction, the guiding mechanism. shown in the previous construction
is strengthened, and all tendency to cramp is eliminated.
These parts are so arranged that there will be no friction between the working
shoulders, that is, the circular working shoulder 610 will turn up and down on the
curved working shoulder 620 without slip..
Therefore, these parts will last for a long time, and, also, it will be seen that these
parts are very strong and will receive the thrust of the bed as close to the bearings
as possible.
In some cases, it is contemplated making the working shoulders and curved
racks separate from the depending brackets, and such constructions are shown
in Figs. 14 and 15.
In Fig. 14, a piece 62 having a curved working shoulder 63 is secured to the
bracket 17, and the curved rack 64 is formed integrally therewith.
In Fig. 15, a curved working shoulder 65 is formed on the bracket 17, and a
semi-circular rack 66 is secured to the bracket, as shown.
As compared with the device shown in the first three sheets of the drawings, the
devices shown in the last two sheets of the drawings distinguishes principally by
the omission of the curved guide way.
The operation of the devices shown in the last two sheets of drawings will be
readily understood.
The parts not specifically referred to operate as described in connection with the
first modification.
Further modifications may be made by a skilled mechanic without departing
from the scope of the invention as expressed in the claims.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:
1. The improvements in mechanical movements for transforming rotary motion
into rectilinearly reciprocating motion, substantially as described."
2. A mechanical movement for transforming rotary motion into rectilinearly
reciprocating motion, comprising a moving member, a mechanism for giving the
same its main forward and backward movement, and a reversing mechanism com-
prising a pinion secured to a revolving crank, and a curved rack at each end of the
bed, arranged so that there will be a continuous mesh of gearing between the
actuating mechanism and moving member, substantially as described.
3. A mechanical movement for transforming rotary motion into rectilinearly
reciprocating motion, consisting of a moving member, a main driving mechanism
for imparting the main forward and backward movement thereto, a reversing
mechanism comprising a pinion mounted on a revolving crank, a curved rack
secured at each end of the moving member, and a guiding mechanism for keeping
the pinion in mesh with one of the curved racks during the reversing movement,
substantially as described.
4. A mechanical movement for transforming rotary motion into rectilinearly
reciprocating motion, comprising a moving member, a main driving mechanism
for imparting the main forward and backward movement to the reciprocating
member, a reversing mechanism consisting of a pinion mounted on a revolving
crank, a curved rack secured to each end of the bed, and a guiding mechanism for
keeping the pinion in mesh with one of the curved racks during the reversing move-
ment, consisting of curved faces and rollers arranged as shown in Fig. 1, sub-
stantially as described.
5. A mechanical movement for transforming rotary motion into rectilinearly
reciprocating motion comprising a moving member, a mechanism for imparting
the main forward and backward movement thereto, a reversing mechanism com-

page_text: prising a pinion mounted on a revolving crank, a curved rack secured to each end
of the bed, and a guiding mechanism for keeping the pinion in mesh during "the
reversing movement consisting of the curved working shoulders, stud and rollers
arranged as shown in Figs. 10, 11 and 12, substantially as described.
Dated this 11th day of September 1897.
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents.